title stringlengths 2 2.62k | resumes stringlengths 1 8.71k | doi stringlengths 13 69 | author listlengths 1 2.39k |
|---|---|---|---|
Build-back-better toward future resiliency and post-COVID transport systems | The COVID-19 pandemic was a real-world stress test for public transport. Different responses and experiences presented in this book show that the sector can be better prepared for the next force majeure that reduces the number of passengers, like pandemic, by setting up a prearranged emergency response plan. To do this, scenario building will be needed with all stakeholders involved. A plan to cover the sudden drop in fare income in such an emergency is strongly recommendable. With the diffusion of teleworking, a long-term legacy of COVID-19, commuting patterns will likely change in future, leading to potential reductions of commuters, who have been the primary customer of public transport. For public transport to remain one of the most environmentally friendly modes of transport, it must proactively address this change. | 10.1016/B978-0-443-13295-7.00005-8 | [
[
"Takeru",
"Shibayama"
],
[
"Guenter",
"Emberger"
]
] |
Remote regions and COVID-19 restrictions caused transport impacts and responses | This chapter summarizes changes and responses of public transport services caused by COVID-19 to and from remote regions, as well as within remote regions. These areas are connected in normal times often by air and sea transport services, which are operated under specific legal frameworks to cofinance commercially loss-making but vital services. With detailed legal situation, background, and the available traffic statistics from the different COVID-19 pandemic periods, we analyze three different areas as case studies: the Azores (Portugal), Adriatic islands (Croatia), and Okinawa (Japan). The result shows that the remote connections show less reduction of both supply and demand compared with routes within the mainland. Tourism-dependent routes saw more demand fall than others, while the fall of vehicle transport and freight demand was limited. | 10.1016/B978-0-443-13295-7.00007-1 | [
[
"Vilmos",
"Oszter"
],
[
"Takeru",
"Shibayama"
],
[
"Takuro",
"Arai"
]
] |
Introduction—Public transport response to COVID-19 from a disaster management perspectives | COVID-19 is a contagious disease caused by SARS-CoV-2. After the first detection in December 2019, it spread worldwide quickly, leading to a pandemic, recording more than 644 million cases and 6.6 million deaths by the end of 2022. In the early phase of the pandemic, many countries put restrictions on human mobility as the center of the containment strategies, leading to large—or “disastrous”—impacts on the public transport sector. Looking from a disaster management perspective—often described as a disaster management cycle, which consists of mitigation, preparation, response, and recovery—this pandemic is unique in that it does not harm the functionality of the public transport system, but the containment measures reduced the travel demand radically, and it also demanded the public transport sector to respond to hygiene measures. It also seems to have changed the travel demand patterns largely through increased use of working from home. | 10.1016/B978-0-443-13295-7.00010-1 | [
[
"Takeru",
"Shibayama"
],
[
"Sachi",
"Suzuki"
]
] |
A Short Introduction to Artificial Intelligence: Methods, Success Stories, and Current Limitations | This chapter gives an overview of the most important methods in artificial intelligence (AI). The methods of symbolic AI are rooted in logic, and finding possible solutions by search is a central aspect. The main challenge is the combinatorial explosion in search, but the focus on the satisfiability problem of propositional logic (SAT) since the 1990s and the accompanying algorithmic improvements have made it possible to solve problems on the scale needed in industrial applications. In machine learning (ML), self-learning algorithms extract information from data and represent the solutions in convenient forms. ML broadly consists of supervised learning, unsupervised learning, and reinforcement learning. Successes in the 2010s and early 2020s such as solving Go, chess, and many computer games as well as large language models such as ChatGPT are due to huge computational resources and algorithmic advances in ML. Finally, we reflect on current developments and draw conclusions. | 10.1007/978-3-031-45304-5_9 | [
[
"Clemens",
"Heitzinger"
],
[
"Stefan",
"Woltran"
]
] |
Federated Learning for Internet of Things | The proliferation of the Internet of Things (IoT) and the advancements in machine learning (ML) have facilitated ubiquitous sensing and computing capabilities, enabling the interconnection of a wide array of devices to the Internet. Traditionally, data collection and data processing have been centralized, which may not be feasible due to issues such as long propagation delays, communication overload, and increasing data privacy concerns. To tackle these challenges, federated learning (FL) has emerged as a privacy-preserving distributed ML approach, allowing numerous devices to engage in model training without transferring their local data to a central server. This work presents a comprehensive review of FL as an approach to performing ML on distributed IoT data, with a specific emphasis on protecting data privacy and reducing communication costs associated with data transfer. The review encompasses various aspects, including the background of FL, the architecture of FL for IoT, the different types of FL for IoT, FL frameworks tailored for IoT, and diverse FL for IoT applications. Additionally, this paper outlines future research challenges and directions pertaining to FL for IoT. By embracing the potential of FL while addressing its challenges, IoT can benefit from reduced delays, improved communication efficiency, enhanced privacy preservation, and a more sustainable FL-IoT system. | 10.1007/978-3-031-50514-0_3 | [
[
"Ying",
"Li"
],
[
"Qiyang",
"Zhang"
],
[
"Xingwei",
"Wang"
],
[
"Rongfei",
"Zeng"
],
[
"Haodong",
"Li"
],
[
"Ilir",
"Murturi"
],
[
"Schahram",
"Dustdar"
],
[
"Min",
"Huang"
]
] |
Intelligence Inference on IoT Devices | With the rapid advancement of artificial intelligence (AI), the proliferation of deep neural networks (DNNs) has ushered in a transformative era, revolutionizing modern lifestyles and enhancing production efficiency. However, the substantial computational and data requirements generated by Internet of Things (IoT) devices present a significant bottleneck, rendering traditional cloud-based computing models inadequate for real-time processing tasks. In response to these challenges, developers have increasingly turned to cloud offloading as a solution, despite the high infrastructure costs and heavy reliance on network conditions associated with this approach. Meanwhile, the emergence of SoCs has enabled on-device execution, particularly on high-tier platforms capable of effectively handling SOTA DNNs. This chapter offers a comprehensive review of intelligent inference approaches, with a specific emphasis on reducing inference time and minimizing transmitted bandwidth between IoT devices and the cloud. The review encompasses various aspects, including the background of inference, hardware architectures supporting inference, a diverse range of intelligent applications, inference libraries tailored for IoT devices, and different types of inference techniques for applications. Additionally, this work addresses the current challenges in intelligent inference, discusses future development trends, and provides future research directions. | 10.1007/978-3-031-50514-0_9 | [
[
"Qiyang",
"Zhang"
],
[
"Ying",
"Li"
],
[
"Dingge",
"Zhang"
],
[
"Ilir",
"Murturi"
],
[
"Victor Casamayor",
"Pujol"
],
[
"Schahram",
"Dustdar"
],
[
"Shangguang",
"Wang"
]
] |
Making waves: The NORMAN antibiotic resistant bacteria and resistance genes database (NORMAN ARB&ARG)–An invitation for collaboration to tackle antibiotic resistance | With the global concerns on antibiotic resistance (AR) as a public health issue, it is pivotal to have data exchange platforms for studies on antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in the environment. For this purpose, the NORMAN Association is hosting the NORMAN ARB&ARG database, which was developed within the European project ANSWER. The present article provides an overview on the database functionalities, the extraction and the contribution of data to the database. In this study, AR data from three studies from China and Nepal were extracted and imported into the NORMAN ARB&ARG in addition to the existing AR data from 11 studies (mainly European studies) on the database. This feasibility study demonstrates how the scientific community can share their data on AR to generate an international evidence base to inform AR mitigation strategies. The open and FAIR data are of high potential relevance for regulatory applications, including the development of emission limit values / environmental quality standards in relation to AR. The growth in sharing of data and analytical methods will foster collaboration on risk management of AR worldwide, and facilitate the harmonization in the effort for identification and surveillance of critical hotspots of AR. The NORMAN ARB&ARG database is publicly available at: https://www.norman-network.com/nds/bacteria/. | 10.1016/j.watres.2024.121689 | [
[
"Nikiforos",
"Alygizakis"
],
[
"Kelsey",
"Ng"
],
[
"Ľuboš",
"Čirka"
],
[
"Thomas",
"Berendonk"
],
[
"Francisco",
"Cerqueira"
],
[
"Eddie",
"Cytryn"
],
[
"Geneviève",
"Deviller"
],
[
"Gianuario",
"Fortunato"
],
[
"I... |
Examining the efficacy of promising antioxidants to mitigate asphalt binder oxidation: insights from a worldwide interlaboratory investigation | Oxidative aging induces significant stiffening of asphalt binders that leads to a pronounced reduction in the overall durability of asphalt pavements. The strategic implementation of antioxidant additives provides a potential solution to alleviate this issue. This work presents results from the second phase of the global consortium for antioxidants research aimed at investigating the effectiveness of potential antioxidants in increasing the durability of asphalt binders. Sixteen laboratories around the world participated in this effort and a total of 28 binders from diverse geographical regions were tested. Two promising antioxidants, namely zinc diethyldithiocarbamate (ZDC) and kraft lignin were evaluated in this phase and blended with the binders at specific proportions. Subsequently, a comprehensive investigation was conducted to assess rheological characteristics and chemical properties of the various blends, utilising Dynamic Shear Rheometer (DSR) measurements and Fourier Transform Infrared (FTIR) Spectroscopy. The findings indicate that additives such as ZDC hold considerable promise as an effective antioxidant, particularly when considering a wide diversity of binders. In general, its incorporation does not compromise the rutting performance of the binders and significantly improves fatigue performance. Therefore, research efforts should be focused on exploring additional facets to assess its practical applicability in field. | 10.1080/10298436.2024.2332363 | [
[
"Dheeraj",
"Adwani"
],
[
"Georgios",
"Pipintakos"
],
[
"Johannes",
"Mirwald"
],
[
"Yudi",
"Wang"
],
[
"Ramez",
"Hajj"
],
[
"Meng",
"Guo"
],
[
"Meichen",
"Liang"
],
[
"Ruxin",
"Jing"
],
[
"Aikaterini",
"Varveri"... |
Determination of high-precision tropospheric delays using crowdsourced smartphone GNSS data | The Global Navigation Satellite System (GNSS) is a key asset for tropospheric monitoring. Currently, GNSS meteorology relies primarily on geodetic-grade stations. However, such stations are too costly to be densely deployed, which limits the contribution of GNSS to tropospheric monitoring. In 2016, Google released the raw GNSS measurement application programming interface for smartphones running on Android version 7.0 and higher. Given that nowadays there are billions of Android smartphones worldwide, utilizing those devices for atmospheric monitoring represents a remarkable scientific opportunity. In this study, smartphone GNSS data collected in Germany as part of the Application of Machine Learning Technology for GNSS IoT Data Fusion (CAMALIOT) crowdsourcing campaign in 2022 were utilized to investigate this idea. Approximately 20?000 raw GNSS observation files were collected there during the campaign. First, a dedicated data processing pipeline was established that consists of two major parts: machine learning (ML)-based data selection and ionosphere-free precise point positioning (PPP)-based zenith total delay (ZTD) estimation. The proposed method was validated with a dedicated smartphone data collection experiment conducted on the rooftop of the ETH campus. The results confirmed that ZTD estimates of millimeter-level precision could be achieved with smartphone data collected in an open-sky environment. The impacts of observation time span and utilization of multi-GNSS observations on ZTD estimation were also investigated. Subsequently, the crowdsourced data from Germany were processed by PPP with the ionospheric delays interpolated using observations from surrounding satellite positioning service of the German National Survey (SAPOS) GNSS stations. The ZTDs derived from ERA5 and an ML-based ZTD product served as benchmarks. The results revealed that an accuracy of better than 10?mm can be achieved by utilizing selected high-quality crowdsourced smartphone data. | 10.5194/amt-17-4303-2024 | [
[
"Yuanxin",
"Pan"
],
[
"Grzegorz",
"Kłopotek"
],
[
"Laura",
"Crocetti"
],
[
"Rudi",
"Weinacker"
],
[
"Tobias",
"Sturn"
],
[
"Linda",
"See"
],
[
"Galina",
"Dick"
],
[
"Gregor",
"Möller"
],
[
"Markus",
"Rothacher"... |
Two-dimensional-materials-based transistors using hexagonal boron nitride dielectrics and metal gate electrodes with high cohesive energy | Two-dimensional (2D) semiconductors could potentially be used as channel materials in commercial field-effect transistors. However, the interface between 2D semiconductors and most gate dielectrics contains traps that degrade performance. Layered hexagonal boron nitride (h-BN) can form a defect-free interface with 2D semiconductors, but when prepared by industry-compatible methods—such as chemical vapour deposition (CVD)—the presence of native defects increases leakage current and reduces dielectric strength. Here we show that metal gate electrodes with a high cohesive energy—platinum and tungsten—can allow CVD-grown layered h-BN to be used as a gate dielectric in transistors. The electrodes can reduce the current across CVD-grown h-BN by a factor of around 500 compared to similar devices with gold electrodes and can provide a high dielectric strength of at least 25 MV cm?¹. We examine the behaviour statistically across 867 devices, which includes a microchip based on complementary metal–oxide–semiconductor technology. | 10.1038/s41928-024-01233-w | [
[
"Yaqing",
"Shen"
],
[
"Kaichen",
"Zhu"
],
[
"Yiping",
"Xiao"
],
[
"Dominic",
"Waldhör"
],
[
"Abdulrahman H.",
"Basher"
],
[
"Theresia",
"Knobloch"
],
[
"Sebastian",
"Pazos"
],
[
"Xianhu",
"Liang"
],
[
"Wenwen",
... |
Investigating building permit processes across Europe: characteristics and patterns | Building permit processes serve as crucial gatekeepers for urban development, regulating compliance with building codes, land use policies, and safety and environmental standards. However, their complexity can lead to inefficiencies and hinder economic growth. While existing studies have made significant contributions to building permit process research, they often focus on individual countries or specific aspects, leaving a gap in comprehensive comparative analysis. Characteristics, and patterns of building permit processes vary widely across jurisdictions due to legal, cultural, technological, and institutional factors which makes a comparative analysis of these variations beneficial. To address the lack of building permit process studies, our research focusses on from an extensive comparative study of building permit processes in 17 European countries. Through semi-structured interviews and process diagrams, we investigate the differences and provide a comparative overview summarizing key characteristics. The findings have the potential to be used by policy makers and practice to better understand and compare the evolution of building permit systems in a broad international context. By bridging research gaps and providing a comprehensive view of these processes, we contribute to the awareness of the diversity of the processes and to fostering greater understanding of building permit processes. | 10.1080/09613218.2024.2400467 | [
[
"Judith",
"Fauth"
],
[
"Peter",
"Nørkjær Gade"
],
[
"Stefanie",
"Kaiser"
],
[
"Kavita",
"Raj"
],
[
"Jonas",
"Goul Pedersen"
],
[
"Per-Ola",
"Olsson"
],
[
"Nicholas",
"Nisbet"
],
[
"Silvia",
"Mastrolembo Ventura"
],
[
... |
All van der Waals Semiconducting PtSe<sub>2</sub> Field Effect Transistors with Low Contact Resistance Graphite Electrodes | Contact resistance is a multifaceted challenge faced by the 2D materials community. Large Schottky barrier heights and gap-state pinning are active obstacles that require an integrated approach to achieve the development of high-performance electronic devices based on 2D materials. In this work, we present semiconducting PtSe2 field effect transistors with all-van-der-Waals electrode and dielectric interfaces. We use graphite contacts, which enable high ION/IOFF ratios up to 10? with currents above 100?µA?µm?¹ and mobilities of 50 cm²?V?¹?s?¹ at room temperature and over 400 cm²?V?¹?s?¹ at 10?K. The devices exhibit high stability with a maximum hysteresis width below 36?mV?nm?¹. The contact resistance at the graphite-PtSe2 interface is found to be below 700 O?µm. Our results present PtSe2 as a promising candidate for the realization of high-performance 2D circuits built solely with 2D materials. | 10.1021/acs.nanolett.4c00956 | [
[
"M. Awais",
"Aslam"
],
[
"Simon",
"Leitner"
],
[
"Shubham",
"Tyagi"
],
[
"Alexandros",
"Provias"
],
[
"Vadym",
"Tkachuk"
],
[
"Egon",
"Pavlica"
],
[
"Martina",
"Dienstleder"
],
[
"Daniel",
"Knez"
],
[
"Kenji",
... |
Riding the waves from epidemic to endemic: Viral mutations, immunological change and policy responses | Nonpharmaceutical interventions (NPI) are an important tool for countering pandemics such as COVID-19. Some are cheap; others disrupt economic, educational, and social activity. The latter force governments to balance the health benefits of reduced infection and death against broader lockdown-induced societal costs. A literature has developed modeling how to optimally adjust lockdown intensity as an epidemic evolves. This paper extends that literature by augmenting the classic SIR model with additional states and flows capturing decay over time in vaccine-conferred immunity, the possibility that mutations create variants that erode immunity, and that protection against infection erodes faster than protecting against severe illness. As in past models, we find that small changes in parameter values can tip the optimal response between very different solutions, but the extensions considered here create new types of solutions. In some instances, it can be optimal to incur perpetual epidemic waves even if the uncontrolled infection prevalence would settle down to a stable intermediate level. | 10.1016/j.tpb.2024.02.002 | [
[
"D.",
"Grass"
],
[
"S.",
"Wrzaczek"
],
[
"J.P.",
"Caulkins"
],
[
"G.",
"Feichtinger"
],
[
"R.F.",
"Hartl"
],
[
"P.M.",
"Kort"
],
[
"M.",
"Kuhn"
],
[
"A.",
"Prskawetz"
],
[
"M.",
"Sanchez-Romero"
],
[
"A... |
Using Rapid Prototyping to Develop a Cell-Based Platform with Electrical Impedance Sensor Membranes for In Vitro RPMI2650 Nasal Nanotoxicology Monitoring | Due to advances in additive manufacturing and prototyping, affordable and rapid microfluidic sensor-integrated assays can be fabricated using additive manufacturing, xurography and electrode shadow masking to create versatile platform technologies aimed toward qualitative assessment of acute cytotoxic or cytolytic events using stand-alone biochip platforms in the context of environmental risk assessment. In the current study, we established a nasal mucosa biosensing platform using RPMI2650 mucosa cells inside a membrane-integrated impedance-sensing biochip using exclusively rapid prototyping technologies. In a final proof-of-concept, we applied this biosensing platform to create human cell models of nasal mucosa for monitoring the acute cytotoxic effect of zinc oxide reference nanoparticles. Our data generated with the biochip platform successfully monitored the acute toxicity and cytolytic activity of 6 mM zinc oxide nanoparticles, which was non-invasively monitored as a negative impedance slope on nasal epithelial models, demonstrating the feasibility of rapid prototyping technologies such as additive manufacturing and xurography for cell-based platform development. | 10.3390/bios14020107 | [
[
"Mateo Gabriel",
"Vasconez Martinez"
],
[
"Eva I.",
"Reihs"
],
[
"Helene M.",
"Stuetz"
],
[
"Astrid",
"Hafner"
],
[
"Konstanze",
"Brandauer"
],
[
"Florian",
"Selinger"
],
[
"Patrick",
"Schuller"
],
[
"Neus",
"Bastus"
],
... |
Transforming Aryl‐Tetrazines into Bioorthogonal Scissors for Systematic Cleavage of <i>trans</i>‐Cyclooctenes | Bioorthogonal bond-cleavage reactions have emerged as a powerful tool for precise spatiotemporal control of (bio)molecular function in the biological context. Among these chemistries, the tetrazine-triggered elimination of cleavable trans-cyclooctenes (click-to-release) stands out due to high reaction rates, versatility, and selectivity. Despite an increasing understanding of the underlying mechanisms, application of this reaction remains limited by the cumulative performance trade-offs (i.e., click kinetics, release kinetics, release yield) of existing tools. Efficient release has been restricted to tetrazine scaffolds with comparatively low click reactivity, while highly reactive aryl-tetrazines give only minimal release. By introducing hydroxyl groups onto phenyl- and pyridyl-tetrazine scaffolds, we have developed a new class of 'bioorthogonal scissors' with unique chemical performance. We demonstrate that hydroxyaryl-tetrazines achieve near-quantitative release upon accelerated click reaction with cleavable trans-cyclooctenes, as exemplified by click-triggered activation of a caged prodrug, intramitochondrial cleavage of a fluorogenic probe (turn-on) in live cells, and rapid intracellular bioorthogonal disassembly (turn-off) of a ligand-dye conjugate. | 10.1002/anie.202411707 | [
[
"Martin",
"Wilkovitsch"
],
[
"Walter",
"Kuba"
],
[
"Patrick",
"Keppel"
],
[
"Barbara",
"Sohr"
],
[
"Andreas",
"Löffler"
],
[
"Stefan",
"Kronister"
],
[
"Andres Fernandez",
"del Castillo"
],
[
"Marion",
"Goldeck"
],
[
... |
Archaeal ether lipids improve internalization and transfection with mRNA lipid nanoparticles | Neutral and positively charged archaeal ether lipids (AEL) have been studied for their utilization as novel delivery systems for pDNA, showing efficient immune response with a strong memory effect while lacking noticeable toxicity. Recent technological advances placed mRNA lipid nanoparticles (LNPs) at the forefront of next-generation delivery systems; however, no study has examined AELs in mRNA delivery yet. In this study, we investigated either a crude lipid extract or the purified tetraether lipid caldarchaeol from Sulfolobus acidocaldarius as potential novel excipients for mRNA LNPs. Depending on their molar share in the respective LNP, particle uptake, and mRNA expression levels could be increased by up to 10-fold in in vitro transfection experiments using both primary cell sources (HSMM) and established cell lines (Caco-2, C2C12) compared to a well-known reference formulation. This increased efficiency might be linked to a substantial effect on endosomal escape, indicating fusogenic and lyotropic features of AELs. This study shows the high value of archaeal ether lipids for mRNA delivery and provides a solid foundation for future in vivo experiments and further research. | 10.1016/j.ejpb.2024.114213 | [
[
"Viktor Laurin",
"Sedlmayr"
],
[
"Silvia",
"Schobesberger"
],
[
"Sarah",
"Spitz"
],
[
"Peter",
"Ertl"
],
[
"David Johannes",
"Wurm"
],
[
"Julian",
"Quehenberger"
],
[
"Oliver",
"Spadiut"
]
] |
Characterization and optimization of a quantitative colorimetric acetylcholine esterase inhibition assay for biochip integration demonstrated by neurotoxicity evaluation of malathion | Organophosphates (OPs) and carbamates as insecticides, nematicides, fungicides, and herbicides are constantly increasing. Their neurotoxic nature requires careful usage, and misuse can lead to fatalities. OPs classified as 'Class 1' toxic compounds irreversibly inhibit cholinesterases due to their molecular structure resembling the natural acetylcholine substrate, leading to toxic events in the human brain. Monitoring such chemicals is relevant for agricultural applications and essential for the military sector to ensure the safety of personnel and civilian populations. State-of-the-art analytical detection methods require time-consuming pre-treatments and costly reagents and face challenges associated with pesticide properties like thermal lability, low volatility, and high polarity, which can compromise analysis performance. Advanced systems like electrophoresis or liquid chromatography are used to address these, but these are not well suited for field analysis. Miniaturized colorimetric assays are becoming more popular for various portable devices and kits (i.e., metabolic or blood cell assays) due to their ease of use and practicality. Here, we aimed to establish and optimize a straight-forward paper-based microfluidic acetylcholine esterase inhibition assay for mobile organophosphate detection, laying the groundwork for future microdevice modules to be used in environmental monitoring, public health, and CBRN applications. | 10.1016/j.snb.2024.135568 | [
[
"Mateo G.",
"Vasconez Martinez"
],
[
"Noemi",
"Parato"
],
[
"Silvia",
"Schobesberger"
],
[
"Florian",
"Selinger"
],
[
"Eva I.",
"Reihs"
],
[
"Sarah",
"Spitz"
],
[
"Martin",
"Frauenlob"
],
[
"Peter",
"Ertl"
],
[
"Ch... |
Learning Semantic Behavior for Human Mobility Trajectory Recovery | Trajectory recovery aims to restore missing data for reconstructing high-quality human mobility trajectory, which benefits a wide range of intelligent transportation system applications ranging from urban planning to travel recommendation. Inspired by the inherent regularity of human mobility, existing approaches capture spatial-temporal transition regularities in historical trajectory for data recovery. Although promising, existing solutions suffer from two limitations. i) These methods fail to recover occasionally-visited points (OVP) due to the lack of semantic information when learning spatial-temporal transition regularities. ii) The information before and after missing data is not be fully utilized for trajectory recovery. To overcome the limitations, we propose a novel semantic-aware trajectory recovery framework. First, we leverage heterogeneous information network (HIN) to encode various semantic correlations for obtaining rich semantic embeddings, which are fused with temporal information to form spatial-temporal semantic context. Then, we develop a behavior attention mechanism to capture semantic behavior transition regularities for trajectory recovery based on the bidirectional spatial-temporal semantic context before and after missing data. Extensive experiments on four real-world datasets show that our proposed method outperforms the state-of-the-arts by 7%-11% in term of recall, F1-score and mean average precision. | 10.1109/TITS.2024.3350234 | [
[
"Wangchen",
"Long"
],
[
"Zhu",
"Xiao"
],
[
"Hongbo",
"Jiang"
],
[
"Yong",
"Xiong"
],
[
"Zheng",
"Qin"
],
[
"You",
"Li"
],
[
"Schahram",
"Dustdar"
]
] |
Technology development of advanced dual fluidized bed steam gasification from pilot to demonstration scale – First results from a newly commissioned 1 MW demonstration plant | The advanced dual fluidized bed steam gasification technology allows the generation of a medium-calorific product gas from various feedstocks. Thereby, biogenic residues, municipal and industrial wastes e.g., sewage sludge or rejects from pulp and paper industry can be utilised. This paper presents the development step of this technology from pilot to demonstration plant scale i.e. the step from technology readiness level 4 to 6. The newly erected demonstration plant at the Syngas Platform Vienna is designed for 1 MWth fuel input power and incorporates a counter current column as the upper part of the gasification. This design choice already resulted in an improvement of product gas quality in pilot scale. By comparing the data gathered from multiple years of 100 kWth pilot scale testing at TU Wien with first results from the new demonstration plant via mass and energy balance simulation, fluidisation regimes and temperature and pressure profiles, the success of the scale-up of the reactor design is proven. The first full load operation achieved a conversion of 1 MW fuel input power into 769 kW product gas power. This translates to 256 kg/h dry biomass being converted into 245 Nm3/h of dry product gas. Although first experiments with the reference feedstock high-grade wood chips showed good reproducibility of the results achieved in pilot scale, challenges still remain. The expected product gas composition was different compared to pilot scale results, as the volume share of hydrogen was lower and the relative content of carbon monoxide and carbon dioxide inverted. While the results show an important intermediate step in the process development, the challenges of improving product gas quality and increasing overall conversion efficiency remain to be tackled. | 10.1016/j.fuel.2024.133376 | [
[
"David",
"Kadlez"
],
[
"Florian",
"Benedikt"
],
[
"Miriam",
"Huber"
],
[
"Katharina",
"Fürsatz"
],
[
"Johannes C.",
"Schmid"
],
[
"Hermann",
"Hofbauer"
],
[
"Stefan",
"Müller"
]
] |
Communications Security in Industry X: A Survey | Industry 4.0 is moving towards deployment using 5G as one of the main underlying communication infrastructures. Thus, the vision of the Industry of the future is getting more attention in research. Industry X (InX) is a significant thrust beyond the state-of-the-art of current Industry 4.0, towards a mix of cyber and physical systems through novel technological developments. In this survey, we define InX as the combination of Industry 4.0 and 5.0 paradigms. Most of the novel technologies, such as cyber-physical systems, industrial Internet of things, machine learning, advances in cloud computing, such as edge and fog computing, and blockchain, to name a few, are converged through advanced communication networks. Since communication networks are usually targeted for security attacks, these new technologies upon which InX relies must be secured to avoid security vulnerabilities propagating into InX and its components. Therefore, in this article, we break down the security concerns of the converged InX-communication networks into the core technologies that tie these, once considered distinct, fields together. The security challenges of each technology are highlighted and potential solutions are discussed. The existing vulnerabilities or research gaps are brought forth to stir further research in this direction. New emerging visions in the context of InX are provided towards the end of the article to provoke further curiosity of researchers. | 10.1109/OJCOMS.2024.3356076 | [
[
"Ijaz",
"Ahmad"
],
[
"Felipe",
"Rodriguez"
],
[
"Tanesh",
"Kumar"
],
[
"Jani",
"Suomalainen"
],
[
"Senthil Kumar",
"Jagatheesaperumal"
],
[
"Stefan",
"Walter"
],
[
"Muhammad Zeeshan",
"Asghar"
],
[
"Gaolei",
"Li"
],
[
... |
Application of a Biomimetic Nanoparticle-Based Mock Virus to Determine SARS-CoV-2 Neutralizing Antibody Levels in Blood Samples Using a Lateral Flow Assay | The presence of neutralizing antibodies against SARS-CoV-2 in blood, acquired through previous infection or vaccination, is known to prevent the (re)occurrence of outbreaks unless the virus mutates. Therefore, the measurement of neutralizing antibodies constitutes an indispensable tool in assessing an individual's and a population's immunity against SARS-CoV-2. For this reason, we have developed an innovative lateral flow assay (LFA) capable of detecting blood-derived neutralizing antibodies using a biomimetic SARS-CoV-2 mock virus system. Here, functionalized gold nanoparticles (AuNPs) featuring the trimeric spike (S) protein at its surface imitate the virus's structure and are applied to monitor the presence and efficacy of neutralizing antibodies in blood samples. The detection principle relies on the interaction between mock virus and the immobilized angiotensin-converting enzyme 2 (ACE2) receptor, which is inhibited when neutralizing antibodies are present. To further enhance the sensitivity of our competitive assay and identify low titers of neutralizing antibodies, an additional mixing pad is embedded into the device to increase the interaction time between mock virus and neutralizing antibodies. The developed LFA is benchmarked against the WHO International Standard (21/338) and demonstrated reliable quantification of neutralizing antibodies that inhibit ACE2 binding events down to a detection limit of an antibody titer of 59 IU/mL. Additional validation using whole blood and plasma samples showed reproducible results and good comparability to a laboratory-based reference test, thus highlighting its applicability for point-of-care testing. | 10.1021/acs.analchem.3c04372 | [
[
"Silvia",
"Schobesberger"
],
[
"Helena",
"Thumfart"
],
[
"Florian",
"Selinger"
],
[
"Sarah",
"Spitz"
],
[
"Carla",
"Gonzalez"
],
[
"Lei",
"Pei"
],
[
"Marko",
"Poglitsch"
],
[
"Peter",
"Ertl"
]
] |
Assessing tropospheric turbulence impact on VGOS telescope placement in the Indian subcontinent for the estimation of earth orientation parameters | The complete set of five Earth Orientation Parameters (EOP) can only be estimated accurately using geodetic Very Long_x000D_
Baseline Interferometry (VLBI). Their precision and accuracy depends on network geometry and station-dependent properties._x000D_
Atmospheric turbulence poses one of the largest error sources for geodetic VLBI, impacting the precision of EOP. Thus, it_x000D_
becomes imperative to consider this factor while choosing the optimal locations for geodetic VLBI. The magnitude of_x000D_
tropospheric turbulence is approximated through the refractive index structure constant, C?²_x000D_
n . In this study, we simulate the optimal locations for geodetic VLBI in India, considering individual tropospheric turbulence parameters per telescope location._x000D_
The study identifies 14 potential VLBI stations, co-located with GPS stations and homogeneously distributed all over India,_x000D_
and computes the C? values from zenith wet delay variances over 24 h obtained from GPS data. These locations are simulated_x000D_
in addition to three different reference networks, which show the current and future VLBI Global Observing System (VGOS)_x000D_
networks. Multiple schedules have been generated and simulated for each configuration using VieSched++, and the precision_x000D_
of EOP is compared when constant and station-specific tropospheric turbulence parameters are used. The study shows that,_x000D_
for the investigated networks, southern stations are optimal for polar motion and celestial pole offsets estimation, whereas_x000D_
an eastern station is optimal for UT1-UTC estimation. Furthermore, the study highlights that for reference networks with_x000D_
fewer stations, utilizing station-specific C? values significantly influences the determination of optimal locations. It further_x000D_
demonstrates how station-specific C? values impact the positioning of VGOS telescopes in each network for each EOP_x000D_
differently. The findings show that higher C? values generally lead to a degradation in EOP precision. Geometrically, a station_x000D_
might be at a good l | 10.1007/s00190-024-01912-8 | [
[
"Arnab",
"Laha"
],
[
"Johannes",
"Böhm"
],
[
"Sigrid",
"Böhm"
],
[
"Matthias",
"Schartner"
],
[
"Hana",
"Krásná"
],
[
"Nagarajan",
"Balasubramanian"
],
[
"Onkar",
"Dikshit"
]
] |
Evidence of contact-induced variability in industrially-fabricated highly-scaled MoS2 FETs | Evidence of microscopic inhomogeneities of the side source/drain contacts in 300 mm wafer integrated MoS2 field-effect transistors is presented. In particular, the presence of a limited number of low Schottky barrier spots through which channel carriers are predominantly injected is demonstrated by the dramatic current changes induced by individual charge traps located near the source contact. Two distinct types of “contact-impacting traps” are identified. Type-1 trap is adjacent to the contact interface and exchanges carriers with the metal. Its impact is only observable when the adjacent contact is the reverse-biased FET source and limits the channel current. Type-2 trap is located in the AlO? gate oxide interlayer, near the source contact, and exchanges carriers with the channel. Its capture/emission time constants exhibit both a gate and drain bias dependence due to the high sensitivity of the contact regions to the applied lateral and vertical fields. Unlike typical channel-impacting oxide traps, both types of reported defects affect the Schottky barrier height and width rather than the threshold voltage and result in giant random telegraph noise (RTN). These observations indicate that the contact quality and geometry play a fundamental role in the ultimate scaling of 2D FETs. | 10.1038/s41699-024-00482-9 | [
[
"Luca",
"Panarella"
],
[
"Ben",
"Kaczer"
],
[
"Quentin",
"Smets"
],
[
"Stanislav",
"Tyaginov"
],
[
"Pablo",
"Saraza Canflanca"
],
[
"Andrea",
"Vici"
],
[
"Devin",
"Verreck"
],
[
"Tom",
"Schram"
],
[
"Dennis",
"... |
Potential of user training for reducing emissions of firewood stoves | Emissions from wood-burning stoves contribute to local air pollution. However, it is difficult to determine the real emissions from such stoves, especially due to unknown user behaviour, which can have a large impact on emissions. In this study, the low-cost emission reduction measure “user training” was evaluated to determine its emission reduction potential on firewood stoves. Two sets of tests were carried out. First, a field measurement campaign was conducted in Styria (Austria) with four wood stoves, where gaseous and particulate emissions were measured before and after a user training on optimised heating behaviour (e.g. ignition mode, fuel properties and placement in the combustion chamber, air supply). Gaseous emissions (carbon monoxide – CO, organic gaseous compounds – OGC) were measured continuously, while particulates were measured in batches, in undiluted and hot as well as in diluted and cooled flue gas in parallel with a specific field measurement setup. In addition, particle filters were analysed to quantify the concentration of the carcinogenic compound benzo(a)pyrene (BaP). Second, user training workshops were conducted. These tests had a simple measurement setup in order to increase the number of tests. Thus, only CO emissions were evaluated. The results show that real life emissions in the field are high and have a high variability compared to laboratory tests and official type test results. However, user training showed a significant reduction of CO, OGC, TSP and BaP emissions of 42%, 57%, 45% and 76% (median), respectively. In addition, TSPsum (sum of hot and cooled particle emission samples) emissions decreased by 39% (median) after user training. The relative reduction rates of all batches show that the highest emission reduction potential was identified for BaP, with a reduction rate of up to 97%. The results of the workshop tests confirmed the high variability in user behavior and the range for the emission reduction potentials, with a media | 10.1016/j.aeaoa.2024.100287 | [
[
"R.",
"Sturmlechner"
],
[
"C.",
"Schmidl"
],
[
"F.",
"Klauser"
],
[
"B.",
"Kirchsteiger"
],
[
"A.",
"Kasper-Giebl"
]
] |
Toward Printing the Brain: A Microstructural Ground Truth Phantom for MRI | Magnetic resonance imaging (MRI) has become the prime imaging technique for in vivo examination of the brain. In addition to anatomical and functional MRI, diffusion MRI (dMRI) is widely used in both clinics and research to assess tissue structure and fiber directions, particularly in the nervous system. While diffusion tensor imaging is the most widespread approach for assessing orientation measures, other, more sophisticated models have also been proposed. Validation of dMRI is, however, a challenging endeavor that requires specialized test samples. Here it is shown that two-photon polymerization (2PP) 3D printing allows for manufacturing such test objects, a.k.a. phantoms. After upscaling the 2PP fabrication process, 3D structures at high spatial resolution and sufficient size to image in a human 7T MRI scanner are created. These phantoms reliably mimic human white matter and thus enable the systematic validation and verification of dMRI data and their analyses. The 3D-printed structures include up to 51 000 microchannels that mimic the diffusion behavior of larger axons, with a cross-section of 12 × 12 µm² each, in parallel and crossing arrangements. The acquired dMRI data demonstrates and verifies the utility of these novel brain phantoms. | 10.1002/admt.202300176 | [
[
"Michael",
"Woletz"
],
[
"Franziska",
"Chalupa‐Gantner"
],
[
"Benedikt",
"Hager"
],
[
"Alexander",
"Ricke"
],
[
"Siawoosh",
"Mohammadi"
],
[
"Stefan",
"Binder"
],
[
"Stefan",
"Baudis"
],
[
"Aleksandr",
"Ovsianikov"
],
... |
The <scp>Wieselburg</scp> Bridge collapse—Analysis of the shear capacity based on forensic data | This paper describes the structural aspects of the Wieselburg Bridge collapse in Austria. The original design and reinforcing details for this integral concrete bridge are discussed. The collapse of the bridge is re-constructed based on forensic documentation of the failure. The results of structural analysis carried out using material properties obtained after failure are compared to the shear capacity obtained from various models and from test results from literature. The results are used to explain the cause of failure of the integral bridge under dead load. | 10.1002/suco.202301005 | [
[
"Tobias",
"Huber"
],
[
"Johann",
"Kollegger"
],
[
"Dominik",
"Suza"
],
[
"Patrick",
"Huber"
]
] |
Counting vanishing matrix-vector products | Consider the following parameterized counting variation of the classic subset sum problem, which arises notably in the context of higher homotopy groups of topological spaces. Let v?Qd be a rational vector, (T1,T2…,Tm) a list of d×d rational matrices, S?Qh×d a rational matrix not necessarily square and k a parameter. The goal is to compute the number of ways one can choose k matrices Ti1,Ti2,…,Tik from the list such that STik?Ti1v=0?Qh. In this paper, we show that this problem is #W[2]-hard for parameter k. As a consequence, computing the k-th homotopy group of a d-dimensional 1-connected topological space for d>3 is #W[2]-hard for parameter k. We also discuss a decision version of the problem and its several modifications for which we show W[1]/W[2]-hardness. This is in contrast to the parameterized k-sum problem, which is only W[1]-hard (Abboud-Lewi-Williams, ESA'14). In addition, we show that the decision version of the problem without parameter is an undecidable problem, and we give a fixed-parameter tractable algorithm for matrices of bounded size over finite fields, parameterized by the matrix dimensions and the order of the field. | 10.1016/j.tcs.2024.114877 | [
[
"Cornelius",
"Brand"
],
[
"Viktoriia",
"Korchemna"
],
[
"Kirill",
"Simonov"
],
[
"Michael",
"Skotnica"
]
] |
DaWiK – Ein KI-gestützter Ansatz für digitales Wissens- und Kompetenzmanagement | DaWiK – An AI-supported Approach for Digital Knowledge and Competence Management – A Case Study from the Automotive Supply Industry. Effective competency management is increasingly vital for companies facing demographic changes and higher turnover, as it enables optimal talent utilization and development, enhancing productivity and work quality. Semantic technologies allow precise modeling and identification of competency gaps, supporting targeted development measures. The DaWiK project has developed a data-driven approach, using the Semantic Text Analysis Pipeline (STAP) to systematically capture requirements from unstructured data like job postings, enabling companies to steer competency development with precision and a future-oriented focus. | 10.1515/zwf-2024-1158 | [
[
"Malte",
"Scheuvens"
],
[
"Pia",
"Mozer"
],
[
"Benedikt",
"Fuchs"
],
[
"Bernd",
"Dworschak"
],
[
"Fazel",
"Ansari"
],
[
"Katharina",
"Hölzle"
]
] |
Exploration of Trichoderma reesei as an alternative host for erythritol production | Background_x000D_
Erythritol, a natural polyol, is a low-calorie sweetener synthesized by a number of microorganisms, such as Moniliella pollinis. Yet, a widespread use of erythritol is limited by high production costs due to the need for cultivation on glucose-rich substrates. This study explores the potential of using Trichoderma reesei as an alternative host for erythritol production, as this saprotrophic fungus can be cultivated on lignocellulosic biomass residues. The objective of this study was to evaluate whether such an alternative host would lead to a more sustainable and economically viable production of erythritol by identifying suitable carbon sources for erythritol biosynthesis, the main parameters influencing erythritol biosynthesis and evaluating the feasibility of scaling up the defined process._x000D_
_x000D_
Results_x000D_
Our investigation revealed that T. reesei can synthesize erythritol from glucose but not from other carbon sources like xylose and lactose. T. reesei is able to consume erythritol, but it does not in the presence of glucose. Among nitrogen sources, urea and yeast extract were more effective than ammonium and nitrate. A significant impact on erythritol synthesis was observed with variations in pH and temperature. Despite successful shake flask experiments, the transition to bioreactors faced challenges, indicating a need for further scale-up optimization._x000D_
_x000D_
Conclusions_x000D_
While T. reesei shows potential for erythritol production, reaching a maximum concentration of 1 g/L over an extended period, its productivity could be improved by optimizing the parameters that affect erythritol production. In any case, this research contributes valuable insights into the polyol metabolism of T. reesei, offering potential implications for future research on glycerol or mannitol production. Moreover, it suggests a potential metabolic association between erythritol production and glycolysis over the pentose phosphate pathway. | 10.1186/s13068-024-02537-x | [
[
"Audrey",
"Masi"
],
[
"Georg",
"Stark"
],
[
"Johanna",
"Pfnier"
],
[
"Robert L.",
"Mach"
],
[
"Astrid R.",
"Mach-Aigner"
]
] |
Sharp conditions for the validity of the Bourgain–Brezis–Mironescu formula | Following the seminal paper by Bourgain, Brezis, and Mironescu, we focus on the asymptotic behaviour of some nonlocal functionals that, for each, are defined as the double integrals of weighted, squared difference quotients of. Given a family of weights, we devise sufficient and necessary conditions on for the associated nonlocal functionals to converge as to a variant of the Dirichlet integral. Finally, some comparison between our result and the existing literature is provided. | 10.1017/prm.2024.47 | [
[
"Elisa",
"Davoli"
],
[
"Giovanni",
"Di Fratta"
],
[
"Valerio",
"Pagliari"
]
] |
Techno-economic evaluation of renewable hydrogen generation strategies for the industrial sector | Renewable hydrogen is considered as one of the key technologies that may be needed to fully decarbonise our economies, providing the high-temperature heat, fuels and feedstock that might not be possible to electrify. Several pilot projects are underway, and some assessments of the economics of green hydrogen have been published. However, most of them have assessed the costs of producing renewable hydrogen in large-scale, grid-connected units. Another option, pointed by many as a robust strategy in the early stages, is to produce hydrogen locally, in “hydrogen valleys”, to serve industrial demand. In this paper, the economics of the different technical configurations and strategies that might be used for this decentralised, variable-demand option are analysed, accounting for the impact that a non-constant operation may cause on the operational efficiency of electrolysers, and for the potential benefits of local hydrogen storage. Our results show that when hydrogen demand is variable, production costs are higher compared to the constant demand case, due to the higher electrolyser size required. Electricity price optimization plus hydrogen storage can be a valuable option in some cases, although the cost benefit is negligible (about 1%) unless price volatility in the market increases with higher RES shares, or investment costs decrease significantly. Sourcing electricity exclusively from a dedicated renewable power plant can only become competitive if electricity market prices rise as observed recently or triggered by increasing CO2 prices. | 10.1016/j.ijhydene.2024.02.167 | [
[
"Jasmine",
"Ramsebner"
],
[
"Pedro",
"Linares"
],
[
"Albert",
"Hiesl"
],
[
"Reinhard",
"Haas"
]
] |
Development of a Flexible Sensor-Integrated Tissue Patch to Monitor Early Organ Rejection Processes Using Impedance Spectroscopy | Heart failure represents a primary cause of hospitalization and mortality in both developed and developing countries, often necessitating heart transplantation as the only viable recovery path. Despite advances in transplantation medicine, organ rejection remains a significant post-operative challenge, traditionally monitored through invasive endomyocardial biopsies (EMB). This study introduces a rapid prototyping approach to organ rejection monitoring via a sensor-integrated flexible patch, employing electrical impedance spectroscopy (EIS) for the non-invasive, continuous assessment of resistive and capacitive changes indicative of tissue rejection processes. Utilizing titanium-dioxide-coated electrodes for contactless impedance sensing, this method aims to mitigate the limitations associated with EMB, including procedural risks and the psychological burden on patients. The biosensor's design features, including electrode passivation and three-dimensional microelectrode protrusions, facilitate effective monitoring of cardiac rejection by aligning with the heart's curvature and responding to muscle contractions. Evaluation of sensor performance utilized SPICE simulations, scanning electron microscopy, and cyclic voltammetry, alongside experimental validation using chicken heart tissue to simulate healthy and rejected states. The study highlights the potential of EIS in reducing the need for invasive biopsy procedures and offering a promising avenue for early detection and monitoring of organ rejection, with implications for patient care and healthcare resource utilization. | 10.3390/bios14050253 | [
[
"Peter",
"Ertl"
],
[
"Tibor",
"Wladimir"
],
[
"Drago",
"Sticker"
],
[
"Patrick",
"Schuller"
],
[
"Mario",
"Rothbauer"
],
[
"Georg",
"Wieselthaler"
],
[
"Martin",
"Frauenlob"
]
] |
Virtual Reality-Powered Wrist Therapy: Developing a Therapist-Driven Exit-the-Room Serious Game with Hand Gesture Interactions | Wrist injuries, driven by factors such as an aging population and the popularity of high-impact sports, have become increasingly prevalent. In response, this study focuses on developing a serious game for wrist injury rehabilitation within a virtual environment, aiming to enhance motivation and therapeutic adherence while highlighting the potential of virtual rehabilitation. Extensive literature research and the involvement of five experts during the game’s design led to the creation of “WristBreakout”, which successfully integrated 13 out of 15 recommended movements into gameplay. In addition, the technical feasibility of the VR headset “MetaQuest” within the domain of wrist rehabilitation was shown. A preliminary evaluation with six healthy participants showed positive results in terms of usability and acceptance (SUS average was 69; UES categories were between 3.97 and 4.77). This work contributes to the broader context of serious games and virtual reality (VR) applications in healthcare, exemplifying how technology can positively impact the rehabilitation experience. | 10.3390/app14114780 | [
[
"René",
"Baranyi"
],
[
"Christoph",
"Hirber"
],
[
"Lukas",
"Roehrling"
],
[
"Christoph",
"Aigner"
],
[
"Dominik",
"Hoelbling"
],
[
"Werner",
"Hoerner"
],
[
"Thomas",
"Grechenig"
]
] |
Global, spatially explicit modelling of zenith wet delay with XGBoost | Radio signals transmitted by Global Navigation Satellite System (GNSS) satellites experience tropospheric delays. While the hydrostatic part, referred to as zenith hydrostatic delay (ZHD) when mapped to the zenith direction, can be analytically modelled with sufficient accuracy, the wet part, referred to as zenith wet delay (ZWD), is much more difficult to determine and needs to be estimated. Thus, there exist several ZWD models which are used for various applications such as positioning and climate research. In this study, we present a data-driven, global model of the spatial ZWD field, based on the Extreme Gradient Boosting (XGBoost). The model takes the geographical location, the time, and a number of meteorological variables (in particular, specific humidity at several pressure levels) as input, and can predict ZWD anywhere on Earth as long as the input features are available. It was trained on ZWDs at 10718 GNSS stations and tested on ZWDs at 2684 GNSS stations for the year 2019. Across all test stations and all observations, the trained model achieved a mean absolute error of 6.1 mm, respectively, a root mean squared error of 8.1 mm. Comparisons of the XGBoost-based ZWD predictions with independently computed ZWDs and baseline models underline the good performance of the proposed model. Moreover, we analysed regional and monthly models, as well as the seasonal behaviour of the ZWD predictions in different climate zones, and found that the global model exhibits a high predictive skill in all regions and across all months of the year. | 10.1007/s00190-024-01829-2 | [
[
"Laura",
"Crocetti"
],
[
"Matthias",
"Schartner"
],
[
"Florian",
"Zus"
],
[
"Wenyuan",
"Zhang"
],
[
"Gregor",
"Moeller"
],
[
"Vicente",
"Navarro"
],
[
"Linda",
"See"
],
[
"Konrad",
"Schindler"
],
[
"Benedikt",
... |
Optimierung des Trittschallschutzes von Holzbalkendecken in Gründerzeithäusern – Teil 2: Deckenaufbau und Flankenübertragung | Optimization of impact sound insulation of wooden beam ceilings in Wilhelminian style houses, Part 2: Ceiling construction and flanking transmission. The research deals with the influence of various parameters in the ceiling structure, such as cavity damping, screed thickness, impact sound insulation, fill and suspended ceilings, on the standard impact sound level of typical Wilhelminian style wooden beam ceilings. The measurements show that a thicker screed, softer impact sound insulation and a heavier fill significantly improve the impact sound level. Binding the fill with polyurethane instead of cement shows a significant improvement in the frequency range from 100 to 500 Hz. While cavity damping with mineral wool only contributes to a limited reduction in the standard impact sound level, decoupling the fill on an elastic intermediate layer delivers significant improvements. The measurements also show that the thickness of the paneling and the type of hangers in suspended ceilings have a significant impact on impact sound insulation. The investigations into flank impact sound transmission make it clear that flank transmission must be taken into account when planning higher requirement levels. Especially in the frequency range between 250 Hz and 800 Hz, the sound transmission of flanking components can play a significant role in the overall transmission. | 10.1002/bapi.202400023 | [
[
"Maximilian",
"Neusser"
],
[
"Paul",
"Wegerer"
]
] |
Optimierung des Trittschallschutzes von Holzbalkendecken in Gründerzeithäusern – Teil 1: Problemstellung und Sanierungsmöglichkeiten | Impact sound insulation in renovated Wilhelminian-style buildings – Part 1: Problem statement and renovation options. Gassner & Partner Baumanagement GmbH, in collaboration with TU Wien, conducted a study to optimize impact sound insulation in Wilhelminian-style building renovations. Historical renovations lacked specific sound standards, causing resident disruption. The research varied parameters like screed thickness, impact sound insulation, aggregate, and suspended subceilings to assess impact sound protection per ÖNORM B 8115-5. Initial analysis of three properties showed reasonable protection in existing wooden beam ceilings. Suspended subceilings significantly improved sound levels, with the spectrum adaptation value CI,50-2500 crucial for higher classification. Measurements during multiple renovations demonstrated that these measures are reproducible and can exceed new construction standards, significantly enhancing living comfort in historic buildings. | 10.1002/bapi.202400022 | [
[
"Maximilian",
"Neusser"
],
[
"Paul",
"Wegerer"
]
] |
An ab initio guided study on the shear-induced fcc-hcp transition: A case study of (Ti,Al)N/ZrN multilayers | The cubic-wurtzite phase transition of (Ti,Al)N-based thin films at high temperatures is the chief determing factor for their thermal stability. Nevertheless, its mechanism of atomic shear is not yet well explored theoretically. Here, we correlate the coherent interfaces with wurtzite formation within (Ti,Al)N/ZrN multilayers by a combined ab initio and experimental study. Compared to (Ti,Al)N, the multilayer exhibits a delayed formation of hexagonal close-packed (hcp) wurtzite-type AlN phase, which is encapsulated by face-centered cubic (fcc-)(Ti,Zr)N and fcc-(Zr,Ti)N layers when annealed at 1200 °C. Based on the orientation relationships of (200)fcc//(0001)hcp and (220)fcc//(01-10)hcp among hcp-AlN and neighboring fcc-(Ti,Zr)N as well as fcc-(Zr,Ti)N by the solid-state nudged elastic band (SS-NEB) method, two mechanisms for atomic shear during fcc-hcp transition are proposed. The introduction of ZrN layers effectively suppresses the fcc-hcp transition, due to higher activation energies induced by the coherent interfaces. | 10.1016/j.scriptamat.2024.116064 | [
[
"Jie",
"Zhang"
],
[
"Chun",
"Hu"
],
[
"Li",
"Chen"
],
[
"Yi",
"Kong"
],
[
"Paul H.",
"Mayrhofer"
]
] |
Effect of asymmetric interfaces on the spinodal decomposition of (Ti,Al)N/ZrN multilayers: First-principles and experimental investigations | Multilayer architectures are effective to tailor the properties of thin films. This study compares the high-temperature structural evolution of (Ti,Al)N and (Ti,Al)N/ZrN by experiments and ab initio calculations. These show that cubic (c-) ZrN layers improve the thermal stability of c-(Ti,Al)N by retarding spinodal decomposition and wurtzite (w-) AlN formation. Correspondingly, (Ti,Al)N and (Ti,Al)N/ZrN exhibit their peak hardness of ~32.8 and 33.2 GPa upon annealing at 800 and 1000 °C, respectively. Already during growth of c-(Ti,Al)N onto c-ZrN additional Ti-rich c-(Ti,Zr)N interlayers form, but this is not the case when growing c-ZrN onto c-(Ti,Al)N. These different boundaries of c-(Ti,Al)N result in different diffusion activation energies for Al, which is higher at the interface to (Ti,Zr)N than at that to ZrN. Consequently, the interface-directed Al diffusion initiates on the side nearby ZrN, which causes an Al concentration gradient within (Ti,Al)N. This increases the spinodal decomposition period, and thus the critical Al content necessary to trigger w-AlN formation is reached later. Detailed experiments show that at 1000 and 1100 °C also at the c-(Ti,Al)N/ZrN interface, where no c-(Ti,Zr)N developed during growth, a thin c-(Ti,Zr)N layer forms. Only when this layers is completely dissolved into ZrN sublayers at 1200 °C, w-AlN is formed. | 10.1016/j.jallcom.2024.175558 | [
[
"Jie",
"Zhang"
],
[
"Chun",
"Hu"
],
[
"Zhe R.",
"Liu"
],
[
"Jian W.",
"Du"
],
[
"Li",
"Chen"
],
[
"She Q.",
"Wang"
],
[
"Yi",
"Kong"
],
[
"Paul H.",
"Mayrhofer"
]
] |
3D printable aliphatic polycarbonate networks from cationic ring-opening photopolymerization of spiro-orthocarbonates | We demonstrate light-based 3D printing of pure poly(ether carbonate) networks free of shrinkage stress. Expanding the recently pioneered concept of pure cationic double ring-opening photopolymerization of spiro-orthoesters at elevated temperatures, we herein investigate spiro-orthocarbonates. Thereof resulting poly(ether carbonate) networks could find manyfold applications in biological and medical settings as well as in applications searching for more sustainable material solutions. We have determined the dependence of single and double ring-opening and the presence of backbiting side reactions for three synthesized spiro-orthocarbonate monomers in combination with an oxetane crosslinker on the ring size and photopolymerization temperature to optimize the photogenerated network and thus material properties. The absence of residual stresses in the polymer network was confirmed by tracking the decrease of sample birefringence with increasing spiro-carbonate monomer content of the sample. Based on this fundamental study, the best-performing monomer was printed in combination with an oxetane crosslinker. | 10.1016/j.eurpolymj.2024.112876 | [
[
"Danijela",
"Kojic"
],
[
"Raffael",
"Wolff"
],
[
"Yazgan",
"Mete"
],
[
"Thomas",
"Koch"
],
[
"Jürgen",
"Stampfl"
],
[
"Stefan",
"Baudis"
],
[
"Katharina",
"Ehrmann"
],
[
"Robert",
"Liska"
]
] |
Methylglyoxal alters collagen fibril nanostiffness and surface potential | Collagen fibrils are fundamental to the mechanical strength and function of biological tissues. However, they are susceptible to changes from non-enzymatic glycation, resulting in the formation of advanced glycation end-products (AGEs) that are not reversible. AGEs accumulate with aging and disease and can adversely impact tissue mechanics and cell-ECM interactions. AGE-crosslinks have been related, on the one hand, to dysregulation of collagen fibril stiffness and damage and, on the other hand, to altered collagen net surface charge as well as impaired cell recognition sites. While prior studies using Kelvin probe force microscopy (KPFM) have shown the effect glycation has on collagen fibril surface potential (i.e., net charge), the combined effect on individual and isolated collagen fibril mechanics, hydration, and surface potential has not been documented. Here, we explore how methylglyoxal (MGO) treatment affects the mechanics and surface potential of individual and isolated collagen fibrils by utilizing atomic force microscopy (AFM) nanoindentation and KPFM. Our results reveal that MGO treatment significantly increases nanostiffness, alters surface potential, and modifies hydration characteristics at the collagen fibril level. These findings underscore the critical impact of AGEs on collagen fibril physicochemical properties, offering insights into pathophysiological mechanical and biochemical alterations with implications for cell mechanotransduction during aging and in diabetes. STATEMENT OF SIGNIFICANCE: Collagen fibrils are susceptible to glycation, the irreversible reaction of amino acids with sugars. Glycation affects the mechanical properties and surface chemistry of collagen fibrils with adverse alterations in biological tissue mechanics and cell-ECM interactions. Current research on glycation, at the level of individual collagen fibrils, is sparse and has focused either on collagen fibril mechanics, with contradicting evidence, or surface potential. He | 10.1016/j.actbio.2024.08.039 | [
[
"Manuel",
"Rufin"
],
[
"Mathis",
"Nalbach"
],
[
"Maja",
"Rakuš"
],
[
"Magdalena",
"Fuchs"
],
[
"Mathias",
"Poik"
],
[
"Georg",
"Schitter"
],
[
"Philipp J.",
"Thurner"
],
[
"Orestis G.",
"Andriotis"
]
] |
AccuStripes: Visual exploration and comparison of univariate data distributions using color and binning | Understanding and analyzing univariate distributions of data in terms of their shapes as well as their specific characteristics, regarding gaps, spikes, or outliers, is crucial in many scientific disciplines. In this paper, we propose a design space composed of the visual channels position and color for representing accumulated distributions. The designs are a mixture of color-coded stripes with density lines. The width and coloring of the stripes is based on the applied binning technique. In a crowd-sourced experiment we explore a subspace, called the AccuStripes (i.e., “accumulated stripes”) design space, consisting of nine representations. These AccuStripes designs integrate three composition strategies (color only, overlay, filled curve) with three binning techniques, one uniform (UB) and two adaptive methods, namely Bayesian Blocks (BB) and Jenks’ Natural Breaks (NB). We evaluate the accuracy, efficiency, and confidence ratings of the nine AccuStripes designs for structural estimation and comparison tasks. Across all study tasks, the overlay composition was found to be most accurate and preferred by observers. Furthermore, the results demonstrate that while no binning method performed best in both identification and comparison, detection of structures using adaptive binning was the most accurate one. For validation we compared the best AccuStripes’ design, i.e., the overlay composition, to line charts. Our results show that the AccuStripes’ design outperformed the line charts in accuracy for all study tasks. | 10.1016/j.cag.2024.103906 | [
[
"Anja",
"Heim"
],
[
"Alexander",
"Gall"
],
[
"Manuela",
"Waldner"
],
[
"Eduard",
"Gröller"
],
[
"Christoph",
"Heinzl"
]
] |
Influence of ex-situ annealing on the friction and wear performance of multi-layer Ti3C2T coatings | 2D materials have gained momentum for lubrication purposes, which holds specifically true under more severe conditions such as elevated temperatures. Among them, MXenes are a new family of 2D materials, which offer an excellent electrical conductivity, tunable surface functionality, and outstanding mechanical properties. In the past five years, MXenes have been significantly studied for tribological applications due to their ability to form easy-to-shear tribofilms with excellent wear resistance. However, little is known regarding MXenes’ tribological performance at elevated temperatures. Therefore, we systematically studied the tribological performance of spray-coated Ti3C2Tx coatings after thermal annealing at temperatures between 50 and 400 °C using linear-reciprocating ball-on-disc tribometry. Advanced materials characterization demonstrated that thermal annealing of MXenes results in the release of superficial and intercalated water, the removal of surface terminations, and the oxidation of Ti3C2Tx to TiO2. Consequently, the tribological performance of the annealed coatings deteriorated, which is particularly pronounced for thin coatings, high normal loads, and elevated annealing temperatures. Our results provide insight into the thermal stability of Ti3C2Tx coatings as well as the implications on their tribological performance. | 10.1016/j.apmt.2023.102020 | [
[
"Guido",
"Boidi"
],
[
"Dario",
"Zambrano"
],
[
"Martín I.",
"Broens"
],
[
"Daniel",
"Moncada"
],
[
"Markus",
"Varga"
],
[
"Manel Rodríguez",
"Ripoll"
],
[
"Ewald",
"Badisch"
],
[
"Nestor",
"Escalona"
],
[
"Philipp ... |
AI-Driven Optimization of PCL/PEG Electrospun Scaffolds for Enhanced In Vivo Wound Healing | Here, an artificial intelligence (AI)-based approach was employed to optimize the production of electrospun scaffolds for in vivo wound healing applications. By combining polycaprolactone (PCL) and poly(ethylene glycol) (PEG) in various concentration ratios, dissolved in chloroform (CHCl3) and dimethylformamide (DMF), 125 different polymer combinations were created. From these polymer combinations, electrospun nanofiber meshes were produced and characterized structurally and mechanically via microscopic techniques, including chemical composition and fiber diameter determination. Subsequently, these data were used to train a neural network, creating an AI model to predict the optimal scaffold production solution. Guided by the predictions and experimental outcomes of the AI model, the most promising scaffold for further in vitro analyses was identified. Moreover, we enriched this selected polymer combination by incorporating antibiotics, aiming to develop electrospun nanofiber scaffolds tailored for in vivo wound healing applications. Our study underscores three noteworthy conclusions: (i) the application of AI is pivotal in the fields of material and biomedical sciences, (ii) our methodology provides an effective blueprint for the initial screening of biomedical materials, and (iii) electrospun PCL/PEG antibiotic-bearing scaffolds exhibit outstanding results in promoting neoangiogenesis and facilitating in vivo wound treatment. | 10.1021/acsami.4c03266 | [
[
"Katarina",
"Virijević"
],
[
"Marko N.",
"Živanović"
],
[
"Dalibor",
"Nikolić"
],
[
"Nevena",
"Milivojević"
],
[
"Jelena",
"Pavić"
],
[
"Ivana",
"Morić"
],
[
"Lidija",
"Šenerović"
],
[
"Luka",
"Dragačević"
],
[
"Ph... |
Process implications on the stability and reliability of 300 mm FAB MoS2 field-effect transistors | Recent advances in fabricating field-effect transistors with MoS2 and other related two-dimensional (2D) semiconductors have inspired the industry to begin with the integration of these emerging technologies into FAB-compatible process flows. Just like in the lab research on 2D devices performed in the last decade, focus during development is typically put on pure technology-related issues, such as low-temperature growth methods of large-area 2D films on target substrates, damage-free transfer from sacrificial substrates and growth of top-gate oxides. With maturing technology, the problem of stability limitations caused by oxide traps is gradually coming into focus now. Thus, here we report an in-depth analysis of hysteresis and bias-temperature instabilities for MoS2 FETs fabricated using a 300 mm FAB-compatible process. By performing a comprehensive statistical analysis on devices with top gate lengths ranging between 18 nm and 10 µm, we demonstrate that aggressive scaling results in additional stability problems, likely caused by defective edges of the scaled top gates, in particular at higher operation temperatures. These are important insights for understanding and addressing the stability limitations in future nanoscale 2D FETs produced using FAB process lines. | 10.1038/s41699-024-00445-0 | [
[
"Yu. Yu.",
"Illarionov"
],
[
"A.",
"Karl"
],
[
"Q.",
"Smets"
],
[
"B.",
"Kaczer"
],
[
"T.",
"Knobloch"
],
[
"L.",
"Panarella"
],
[
"T.",
"Schram"
],
[
"S.",
"Brems"
],
[
"D.",
"Cott"
],
[
"I.",
"Ass... |
d-Allulose production via a simplified in vitro multienzyme cascade strategy: Biosynthesis and crystallization | d-Allulose is a rare sugar with multiple physiological functions whose application has been restricted by low conversion rate, weak thermostability of the used enzymes, and complex production. In this study, a simplified multienzyme cascade strategy was designed for biosynthesis of d-allulose from d-glucose, and a detailed investigation of the crucial enzyme allulose 6-phosphate phosphatase was conducted. Under optimized conditions, the yield of d-allulose reached 4.12 ± 0.14 and 80.20 ± 3.20 mmol/L using 10.0 and 200.0 mmol/L d-glucose as substrate, respectively. Furthermore, the influence of various factors on the cooling crystallization of d-allulose was investigated, and the crystallization process was optimized. Consequently, a crystallization recovery rate of 77.43% ± 2.50% and a purity of 98.70% ± 0.05% were achieved. Moreover, the obtained crystals of d-allulose were characterized by XRD, TGA-DSC, and optical microscopy. | https://doi.org/10.1016/j.fbio.2024.105507 | [
[
"Han",
"Zhang"
],
[
"Zhen",
"Sun"
],
[
"Xinling",
"Du"
],
[
"Qianqian",
"Cheng"
],
[
"Fuchun",
"Ji"
],
[
"Zishen",
"Nie"
],
[
"Julei",
"Zhan"
],
[
"Zhouping",
"Wang"
],
[
"Aitao",
"Li"
],
[
"Irina",
... |
Toward Synthetic Physical Fingerprint Targets | Biometric fingerprint identification hinges on the reliability of its sensors; however, calibrating and standardizing these sensors poses significant challenges, particularly in regards to repeatability and data diversity. To tackle these issues, we propose methodologies for fabricating synthetic 3D fingerprint targets, or phantoms, that closely emulate real human fingerprints. These phantoms enable the precise evaluation and validation of fingerprint sensors under controlled and repeatable conditions. Our research employs laser engraving, 3D printing, and CNC machining techniques, utilizing different materials. We assess the phantoms' fidelity to synthetic fingerprint patterns, intra-class variability, and interoperability across different manufacturing methods. The findings demonstrate that a combination of laser engraving or CNC machining with silicone casting produces finger-like phantoms with high accuracy and consistency for rolled fingerprint recordings. For slap recordings, direct laser engraving of flat silicone targets excels, and in the contactless fingerprint sensor setting, 3D printing and silicone filling provide the most favorable attributes. Our work enables a comprehensive, method-independent comparison of various fabrication methodologies, offering a unique perspective on the strengths and weaknesses of each approach. This facilitates a broader understanding of fingerprint recognition system validation and performance assessment. | 10.3390/s24092847 | [
[
"Laurenz",
"Ruzicka"
],
[
"Bernhard",
"Strobl"
],
[
"Stephan",
"Bergmann"
],
[
"Gerd",
"Nolden"
],
[
"Tom",
"Michalsky"
],
[
"Christoph",
"Domscheit"
],
[
"Jannis",
"Priesnitz"
],
[
"Florian",
"Blümel"
],
[
"Bernha... |
High-field magnetization of
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mrow><mml:mi>KEr</mml:mi><mml:mo>(</mml:mo><mml:msub><mml:mi>MoO</mml:mi><mml:mn>4</mml:mn></mml:msub><mml:mo>)</mml:mo></mml:mrow><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math> | We report a magnetization study of the rare-earth-based paramagnet KEr(MoO4)2 in a magnetic field up to 50 T. A recent observation of massive magnetostriction and rotational magnetocaloric effects in this compound triggered interest in the microscopic mechanism behind these phenomena. We combine several experimental techniques to investigate the magnetization behavior up to its saturation along three main crystallographic directions. The synergy of magnetic torque measurements and vibrating sample magnetometry allowed us to reconstruct parallel and perpendicular components of the magnetization vector, enabling us to trace its evolution up to 30 T. Our experiments reveal the magnetization saturation along all principle axes well below the value, expected from crystal electric field calculations. We argue that an externally applied magnetic field induces a distortion of the local environment of Er3+ ions and affects its crystal electric field splitting. | 10.1103/PhysRevB.109.024438 | [
[
"K.",
"Kutko"
],
[
"B.",
"Bernáth"
],
[
"V.",
"Khrustalyov"
],
[
"O.",
"Young"
],
[
"H.",
"Engelkamp"
],
[
"P. C. M.",
"Christianen"
],
[
"L.",
"Prodan"
],
[
"Y.",
"Skourski"
],
[
"L. V.",
"Pourovskii"
],
[... |
Characterizing the 80 GHz Channel in Static Scenarios: Diffuse Reflection, Scattering, and Transmission Through Trees Under Varying Weather Conditions | The deployment of wireless systems in millimeter wave relies on a thorough understanding of electromagnetic wave propagation under various weather conditions and scenarios. In this study, we characterize millimeter wave propagation effects from measurement data, utilizing channel impulse response analysis with a focus on root mean square delay spread and Rician K -factor. The obtained results highlight the significant influence of weather conditions and foliage on propagation, including diffuse reflection, scattering, and absorption. Particularly, we observed a notable increase in scattering from deciduous trees with leaves, in comparison with bare trees or ones covered by snow or ice. The attenuation of the signal propagated through a tree with foliage is 2.16 dB/m higher compared to a bare tree. Our validation measurements within a semi-anechoic chamber confirmed these observations and aided in quantifying the differences. These findings offer valuable insights into the dynamics of millimeter-wave signals that are important for advancing wireless communication technologies. | 10.1109/ACCESS.2024.3472003 | [
[
"Radek",
"Zavorka"
],
[
"Tomas",
"Mikulasek"
],
[
"Josef",
"Vychodil"
],
[
"Jiri",
"Blumenstein"
],
[
"Aniruddha",
"Chandra"
],
[
"Hussein",
"Hammoud"
],
[
"Jan M.",
"Kelner"
],
[
"Cezary",
"Ziółkowski"
],
[
"Thoma... |
Structural Characterization of La0.6Sr0.4CoO3−δ Thin Films Grown on (100)-, (110)-, and (111)-Oriented La0.95Sr0.05Ga0.95Mg0.05O3−δ | In this study, a detailed structural characterization of epitaxial La0.6Sr0.4CoO3?d (LSC) films grown in (100), (110), and (111) orientations was conducted. LSC is a model air electrode material in solid oxide fuel and electrolysis cells and understanding the correlation of bulk structure and catalytic activity is essential for the design of future electrode materials. Thin films were grown on single crystals of the perovskite material La0.95Sr0.05Ga0.95Mg0.05O3?d cut in three different directions. This enabled an examination of structural details at the atomic scale for a realistic material combination in solid oxide cells. The investigation involved the application of atomic force microscopy, X-ray diffraction, and high-resolution transmission electron microscopy to explore the distinct properties of these thin films. Interestingly, ordering phenomena in both cationic as well as anionic sublattices were found, despite the fact that the thin films were never at higher temperatures than 600 °C. Cationic ordering was found in spherical precipitates, whereas the ordering of oxygen vacancies led to the partial transition to brownmillerite in all three orientations. Our results indicate a very high oxygen vacancy concentration in all three thin films. Lattice strains in-plane and out-of-plane was measured, and its implications for the structural modifications are discussed. | 10.3390/ma17081802 | [
[
"Sergej",
"Ražnjević"
],
[
"Sandra",
"Drev"
],
[
"Andreas E.",
"Bumberger"
],
[
"Maxim N.",
"Popov"
],
[
"Matthäus",
"Siebenhofer"
],
[
"Christin",
"Böhme"
],
[
"Zhuo",
"Chen"
],
[
"Yong",
"Huang"
],
[
"Christoph",... |
Polymerized ionic liquid Co-catalysts driving photocatalytic CO<sub>2</sub> transformation | Photocatalytic production of CO from CO2 has the potential for safe and atom-economic production of feedstock chemicals via in situ carbonylation chemistry. We developed novel ionic liquid-based polymeric materials through radical copolymerisation of 1-butyl-3-vinylimidazolium chloride and photocatalytically active Re- and Ru-complexes that serve as the CO2 reduction catalyst and photosensitiser, respectively. The crosslinked polymeric framework allows for the facile immobilisation of molecular organometallic complexes for use as heterogenised catalysts; moreover, the involved imidazolium core units co-catalyze the reduction of CO2 via covalent interaction. The ratio of sensitiser and catalyst was analysed by laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) and set in relation to results from photocatalytic experiments. Ultimately, the heterogenous polymeric framework showed high selectivity for CO formation on photocatalytic CO2 reduction with improved stability to the corresponding homogenous system. | 10.1039/d4su00194j | [
[
"Lisa",
"Eisele"
],
[
"Bletë",
"Hulaj"
],
[
"Maximilian",
"Podsednik"
],
[
"Francesco",
"Laudani"
],
[
"Pablo",
"Ayala"
],
[
"Alexey",
"Cherevan"
],
[
"Annette",
"Foelske"
],
[
"Andreas",
"Limbeck"
],
[
"Dominik",
... |
Cu-doped perovskite-type oxides: A structural deep dive and examination of their exsolution behaviour influenced by B-site doping | Perovskite-type oxides have gained significant attention in the scientific community due to their unique properties and potential applications. Their ability to exsolve reducible B-site cations (e.g. Co, Ni, Cu) combined with their flexibility regarding A-site and B-site composition allows for the tailoring of novel catalytic materials. This study focuses on B-site doped perovskite-type oxides with a general formula of Nd0.6Ca0.4Fe1??Cu?O3 and Pr0.6Ca0.4Fe1??Cu?O3 (x = 0.0, 0.03, 0.05, 0.10) for potential use as a catalyst for Methanol Steam Reforming via the exsolution of catalytically active Cu nanoparticles. The atomic and electronic structure, morphology, and exsolution behaviour of these materials were investigated experimentally and with density functional theory, with a specific emphasis on the impact of B-site doping with varying Cu content as well as choice of A-site element. Both parameters influenced the crystal structure, surface area, and morphology of the materials. The exsolution behaviour of the materials was observed using in-situ XRD at DESY beamline P02.1 at PETRA III, with nanoparticles forming after reductive treatments on the host oxide surface. The quantity and size of the nanoparticles were found to be adjustable by selecting the A-site ion, doping content at the B-site, and the choice of reducing agent. Materials with higher Cu content on the B-site exhibited facilitated exsolution. Furthermore, exsolution was promoted with Nd as the A-site element compared to Pr. In conclusion, the controlled exsolution of Cu nanoparticles introduces Cu-doped perovskite-type oxides as promising candidates for developing novel catalytic systems. The findings underscore the importance of fine-tuning the oxide composition (A-site element, amount of B-site dopant) to achieve tailored exsolution of nanoparticles, which is crucial for rational material design. By leveraging this knowledge, catalysts with finely tuned properties can be created for specific applica | 10.1016/j.cattod.2024.114787 | [
[
"Tobias",
"Berger"
],
[
"Hedda",
"Drexler"
],
[
"Thomas",
"Ruh"
],
[
"Lorenz",
"Lindenthal"
],
[
"Florian",
"Schrenk"
],
[
"Johannes",
"Bock"
],
[
"Raffael",
"Rameshan"
],
[
"Karin",
"Föttinger"
],
[
"Johanna",
... |
Synthesis, structure, photo- and electroluminescent properties of methyl- and alkoxy-substituted 4-methyl-N-[2-(phenyliminomethyl)phenyl]benzenesulfamides and their zinc(II) complexes | A series of novel Zn(II) bischelate complexes based on azomethines of 2-(N-tosylamino)benzaldehyde and aromatic_x000D_
amines (aniline, 4-methylaniline, 4-methoxyaniline, 2-methoxylaniline, and 4-ethoxylanine) were_x000D_
designed and synthesized with the aim of studying their photo- and electro-luminescent properties. The structures_x000D_
of the synthesized azomethines and their complexes were studied by elemental analysis, infrared (IR) and_x000D_
proton nuclear magnetic resonance (1H NMR) spectroscopy. The structure of the Zn(II)-complexes was determined_x000D_
using X-ray diffraction analysis. In the solid state, azomethines exhibit bright luminescence in the yellow_x000D_
part of the spectrum with high emission efficiency and quantum yields of approximately 50 %. Zinc complexes_x000D_
based on them exhibit noticeable luminescence in the solid state and in solutions of methylene chloride._x000D_
Compared to azomethines, the luminescence maxima of Zn(II) complexes are hypsochromically shifted, and they_x000D_
exhibit pronounced blue-green luminescence. The OLED devices based on zinc(II) complexes emit strong bluishgreen_x000D_
light with a peak maximum at 478–490 nm. The device with the best parameters has a maximum luminance_x000D_
of 2103 cd/m², a current efficiency of 14.0 cd/A, and an overall efficiency of 4.8 %, with a turn-on voltage_x000D_
of 3.6 V. | 10.1016/j.optmat.2024.116412 | [
[
"Anatolii S.",
"Burlov"
],
[
"Valery G.",
"Vlasenko"
],
[
"Yurii V.",
"Koshchienko"
],
[
"Bogdan V.",
"Chaltsev"
],
[
"Oleg P.",
"Demidov"
],
[
"Alexandra A.",
"Kolodina"
],
[
"Dmitrii A.",
"Garnovskii"
],
[
"Elena V.",
"B... |
Enhanced photochemical effects of plasmonic cluster catalysts through aggregated nanostructures | Here we present an effective strategy to achieve strongly enhanced catalytic activity of platinum-copper bimetallic clusters through augmented plasmonic photochemical effects of an aggregated nanostructure. The excitation by light irradiation significantly amplified both the population and migration rate of hot carriers generated on the catalyst surface, thereby achieving a record-high reduction rate of p-nitrophenol at elevated concentration. This work provides important insights for the rational design of efficient metallic photocatalysts; it is also relevant for further improvement of the efficiencies of plasmonic photocatalysis and solar energy harvesting. | 10.1039/D4GC00560K | [
[
"Xu",
"Hu"
],
[
"Zhijie",
"Zhu"
],
[
"Yuxuan",
"Zhou"
],
[
"Shuang",
"Liu"
],
[
"Chunpeng",
"Wu"
],
[
"Jiaqi",
"Wang"
],
[
"Yihao",
"Shen"
],
[
"Tianran",
"Yan"
],
[
"Liang",
"Zhang"
],
[
"Jinxing",
... |
Assessing spatial distribution of bioindicator elements in various cutaneous tumors using correlative imaging with laser-ablation-based analytical methods | Correlative imaging of cutaneous tumors provides additional information to the standard histopathologic examination. However, the joint progress in the establishment of analytical techniques, such as Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in clinical practice is still limited. Their combination provides complementary information as it is also shown in our study in terms of major biotic (Ca, Mg, and P) and trace (Cu and Zn) elements. To elucidate changes in the elemental composition in tumors, we have compiled a set of malignant tumors (Squamous Cell Carcinoma, Basal Cell Carcinoma, Malignant Melanoma, and Epithelioid Angiosarcoma), one benign tumor (Pigmented Nevus) and one healthy-skin sample. The data processing was based on a methodological pipeline involving binary image registration and affine transformation. Thus, our paper brings a feasibility study of a practical methodological concept that enables us to compare LIBS and LA-ICP-MS results despite the mutual spatial distortion of original elemental images. Moreover, we also show that LIBS could be a sufficient pre-screening method even for a larger number of samples according to the speed and reproducibility of the analyses. Whereas LA-ICP-MS could serve as a ground truth and reference technique for preselected samples. | 10.1016/j.talanta.2024.126651 | [
[
"Kateřina",
"Kiss"
],
[
"Hana",
"Kopřivová"
],
[
"Václav",
"Stejskal"
],
[
"Lukáš",
"Krbal"
],
[
"Jakub",
"Buday"
],
[
"Lukas",
"Brunnbauer"
],
[
"Erik",
"Képeš"
],
[
"Pavel",
"Pořízka"
],
[
"Aleš",
"Ryška"
]... |
Zinc (II) complexes with Schiff bases obtained from <i>N</i>‐[2‐(cyclohexyliminomethyl)‐ or 2‐(4‐cyclohexylphenyliminomethyl) phenyl]‐4‐methylbenzenesulfonamides and their application as highly luminescent blue emitters for OLEDs | Two new Schiff base compounds of N-{2-[(E)-?yclohexyliminomethyl]phenyl}- 4-methylbenzenesulfonamide, N-{2-[(E)-(4-?yclohexylphenyl)iminomethyl] phenyl}-4-methylbenzenesulfonamide and their Zn(II) complexes have been synthesized and characterized by elemental analysis, FT-IR and UV–Vis spectra, and single crystal X-ray determination. In both complexes, Zn2+ ions have a tetrahedral environment with two nitrogen atoms of the tosylamide groups and two nitrogen atoms of the imine fragment. Time-dependent density functional theory calculations have been performed on two zinc(II) complexes in order to assign their experimental UV–visible absorption bands. Zinc(II) complexes showed thermal stability up to 335–340 C under a nitrogen atmosphere by thermogravimetric analysis (TGA). The photoluminescent spectra show that both Zn(II) complexes in the solid state at room temperature emit blue luminescence with high emission quantum yields of 20% and 29%. The doped devices with configurations of indium tin oxide (ITO)/poly (3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/N,N0- Di(1-naphthyl)-N,N0-diphenyl-(1,10-biphenyl)-4,40-diamine (NPD)/4,40-N,N0 -dicarbazolebiphenyl (CBP):Zinc(II) complex (5%)/1,3,5-tris(N-phenylbenzimidazole- 2-yl) benzene (TPBI)/LiF/Al have been fabricated and investigated. The doped device based on the complex with the ?yclohexylphenyl substituent of the ligand showed the best electroluminescent characteristics with maximum brightness Lmax of 3415 cd/m2, maximum current efficiency of 2.8 cd/A, and power efficiency of 1.9 lm/W, while the doped device with emitter on the base of the complex with the ?yclohexyl substituent showed slightly worse electroluminescence (EL) performance with Lmax of 2105 cd/m2, maximum current efficiency of 2.1 cd/A, and power efficiency of 1.6 lm/W. | 10.1002/aoc.7375 | [
[
"Anatolii S.",
"Burlov"
],
[
"Yurii V.",
"Koshchienko"
],
[
"Valery G.",
"Vlasenko"
],
[
"Oleg P.",
"Demidov"
],
[
"Bogdan V.",
"Chaltsev"
],
[
"Mikhail A.",
"Kiskin"
],
[
"Dmitrii A.",
"Garnovskii"
],
[
"Alexandra A.",
"K... |
Continuous Enantioselective α-Alkylation of Ketones via Direct Photoexcitation | Motivated by the scarcity of enantioselective direct intermolecular a-alkylation reactions of ketones with simple alkyl halides, we report a photo-organocatalytic process to access diethyl 2-(2-oxocyclohexyl)malonate and derivatives in good yield and enantioselectivity. The reaction design is based on highly abundant and nature-derived 9-amino-9-deoxy-epi-cinchona alkaloids to activate ketones as transient secondary enamines, which exist unfavorably in equilibrium with imines. These condensed species can serve as powerful photoinitiators via direct photoexcitation. This concept provides access to both enantiomeric antipodes. In addition to introducing an uncomplicated batch-optimized procedure, we investigated the feasibility and limitations of implementing the reaction in continuous flow, thus enabling to obtain diethyl 2-(2-oxocyclohexyl)malonate with a productivity of 47 µmol/h and 84% enantioselectivity. | 10.1021/acs.joc.4c00759 | [
[
"Michael",
"Weiser"
],
[
"Ádám Márk",
"Pálvölgyi"
],
[
"Matthias",
"Weil"
],
[
"Katharina",
"Bica-Schröder"
]
] |
Vibrational properties of monoclinic
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>CoTe</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:mrow></mml:math> | The vibrational properties of monoclinic dirutile-type CoTeO4 (space group P21/c) were investigated by means of Raman and infrared (IR) spectroscopy on stoichiometric single crystals and theoretical density-functional theory (DFT) calculations. Experimental in situ investigations under pressure and temperature variations up to 10.1 GPa and 750 K confirmed the singular phase stability of the monoclinic lattice and the absence of any structural transition. The IR spectra exhibit modes that are not observed in the Raman spectra, thus offering a comprehensive understanding of the vibrational behavior of the title compound. The symmetry and degeneracy of modes and their contributions to the overall vibrational spectrum of CoTeO4 were analyzed using group theory. DFT calculations were performed both on a cluster level and based on the crystal structure of monoclinic CoTeO4 in order to gain further insights into the vibrational properties. The calculated vibrational frequencies and modes were compared with the experimental data, allowing for a detailed investigation of the lattice dynamics and the nature of the vibrational modes in CoTeO4, and are corroborated with the analytical Wilson's F-G matrix method. These findings provide fundamental insights into the crystal symmetry and lattice dynamics of CoTeO4. The results are discussed and compared to those of isoformular systems. | 10.1103/PhysRevB.110.054104 | [
[
"P.",
"Pramanik"
],
[
"F.",
"Eder"
],
[
"M.",
"Weil"
],
[
"S. A.",
"Ivanov"
],
[
"P.",
"Maltoni"
],
[
"R.",
"Miletich"
],
[
"T.",
"Edvinsson"
],
[
"R.",
"Mathieu"
]
] |
High-energy CID tandem TOF-MS of various types of precursor ions of selected diether phospholipids: Diagnostic known and unexpected fragmentation pathways | The fragmentation behavior of some selected synthetic (1,2-diphytanyl- and 1,2-dihexadecyl-glycerophosphatidylethanolamine, 1,2-diphytanyl- and 1,2-dihexadecyl-glycerophosphatidylcholine) as well as of one natural diether phospholipid (2,3-diphytanyl-glycerophosphatidylinositol), the latter obtained from extracts of the archaeon Sulfolobus acidocaldaricus, was described by negative- and positive-ion MALDI high-energy CID tandem time-flight mass spectrometry for the first time. In contrast to the fragmentation pathways of classical diester glycerophospholipids, whose fragmentation behavior is already well described, the investigated diether glycerophospholipids exhibited a very different fragmentation behavior. The [M–H]?-precursor ions (ethanolamine, inositol) showed abundant high-mass charge-remote site fragmentation of the alkyl chains with easy determination of all methyl branching points (if present). Corresponding low mass product ions elucidated the identity of the polar head group. In contrast, [M+H]?-precursor ions of ethanolamine derivatives showed unusual loss of H3PO4 directly from the precursor ion and McLafferty-like rearrangements of selected product ions differing between sn1-and sn2-substituents, [R1O+58]? and [R2O+42]? ions, respectively. No diagnostic low mass product ions or high mass charge-remote site fragmentations are observed. A yet undescribed rearrangement reaction for protonated diether phosphocholine derivates was found by an intramolecular transesterification rearrangement of the precursor ion forming protonated O-alkyl glycerophosphatidylcholine. Besides, high mass charge-remote site fragmentation of the alkyl chains was observed. High-energy CID-spectra of [M+Na]?-precursor ions showed only little fragmentation (ethanolamine, inositol) with abundant partial polar head group losses and low mass head group product ions. In contrast, the [M+Na]?-precursor ions of corresponding choline derivatives showed significant charge-remote site frag | 10.1016/j.ijms.2024.117237 | [
[
"Ernst",
"Pittenauer"
],
[
"Julian",
"Quehenberger"
],
[
"Viktor",
"Sedlmayr"
],
[
"Martina",
"Marchetti-Deschmann"
],
[
"Oliver",
"Spadiut"
]
] |
Integrated Optics Waveguides and Mesoporous Oxides for the Monitoring of Volatile Organic Compound Traces in the Mid-Infrared | Volatile organic compounds (VOCs) are an ever-growing hazard for health and environment due to their increased emissions and accumulation in the air. Quantum cascade laser-based infrared (QCL-IR) sensors hold significant promise for gas monitoring, thanks to their compact, rugged design, high laser intensity, and high molecule-specific detection capabilities within the mid-infrared spectrum's fingerprint region. In this work, tunable external cavity QCLs were complemented by an innovative germanium-on-silicon integrated optics waveguide sensing platform with integrated microlenses for efficient backside optical interfacing for the tunable laser spectrometer. The waveguide chip was coated with a mesoporous silica coating, thereby increasing the signal by adsorptive enhancement of VOCs while at the same time limiting water vapor interferences. Different least square fitting methods were explored to deconvolute the resulting spectra, showing subparts-per-million by volume (sub-ppmv) limits of detection and enrichment factors of up to 22?000 while keeping the footprint of the setup small (29?×?23?×?11 cm³). Finally, a use-case simulation for the continuous detection of VOCs in a process analytical technology environment confirmed the high potential of the technique for the monitoring of contaminants. By successfully demonstrating the use of photonic waveguides for the monitoring of VOCs, this work offers a promising avenue for the further development of fully integrated sensors on a chip. | 10.1177/00037028241300554 | [
[
"Felix",
"Frank"
],
[
"Bettina",
"Baumgartner"
],
[
"Mattias",
"Verstuyft"
],
[
"Nuria",
"Teigell Beneitez"
],
[
"Jeroen",
"Missinne"
],
[
"Dries",
"Van Thourhout"
],
[
"Gunther",
"Roelkens"
],
[
"Bernhard",
"Lendl"
]
] |
Mn-promoted MoS<sub>2</sub> catalysts for CO<sub>2</sub> hydrogenation: enhanced methanol selectivity due to MoS<sub>2</sub>/MnO<sub><i>x</i></sub> interfaces | Considering the alarming scenario of climate change, CO2 hydrogenation to methanol is considered a key process for phasing out fossil fuels by means of CO2 utilization. In this context, MoS2 catalysts have recently shown to be promising catalysts for this reaction, especially in the presence of abundant basal-plane sulfur vacancies and due to synergistic mechanisms with other phases. In this work, Mn-promoted MoS2 prepared by a hydrothermal method presents considerable selectivity for CO2 hydrogenation to methanol in comparison with pure MoS2 and other promoters such as K and Co. Interestingly, if CO is used as a carbon source for the reaction, methanol production is remarkably lower, which suggests the absence of a CO intermediate during CO2 hydrogenation to methanol. After optimization of synthesis parameters, a methanol selectivity of 64% is achieved at a CO2 conversion of 2.8% under 180 °C. According to material characterization by X-ray Diffraction and X-ray Absorption, the Mn promoter is present mainly in the form of MnO and MnCO3 phases, with the latter undergoing convertion to MnO upon H2 pretreatment. However, following exposure to reaction conditions, X-ray photoelectron spectroscopy suggests that higher oxidation states of Mn may be present at the surface, suggesting that the improved catalytic activity for CO2 hydrogenation to methanol arises from a synergy between MoS2 and MnOx at the catalyst surface. | 10.1039/d3cy01711g | [
[
"Gustavo A. S.",
"Alves"
],
[
"Gernot",
"Pacholik"
],
[
"Stephan",
"Pollitt"
],
[
"Tobias",
"Wagner"
],
[
"Raffael",
"Rameshan"
],
[
"Christoph",
"Rameshan"
],
[
"Karin",
"Föttinger"
]
] |
A New Family of Fe(II) 1‐Propyl‐<i>1H</i>‐Imidazole Complexes with Mono‐, Bi‐, and Tetra‐Nuclear Members | The synthesis of [Fe(PrIm)6](BF4)2 with the intention of investigating its magnetic and structural properties led to the discovery of a new family of Fe(II) 1-propyl-1H-imidazole complexes, which were obtained by simply changing the reaction conditions. The structural, magnetic and electronic properties were investigated. | 10.1002/ejic.202400358 | [
[
"Willi",
"Zeni"
],
[
"Danny",
"Müller"
],
[
"Marco",
"Seifried"
],
[
"Jan M.",
"Welch"
],
[
"Berthold",
"Stöger"
],
[
"Gerald",
"Giester"
],
[
"Michael",
"Reissner"
],
[
"Ronald",
"Miletich"
],
[
"Peter",
"Wein... |
Tetrakis-Cyanoacetylides as Building Blocks for a Second Generation of Spin-Switchable Hofmann-type Networks with Enhanced Porosity | The combination of spin crossover (SCO) with guest incorporation properties has attracted the interest of researchers in the last couple of decades and has led to the design of numerous SCO porous coordination polymers (SCO-PCPs). The most famous class of SCO-PCPs is the Hofmann-type network, which is a very promising material for (chemo)sensing applications. Different strategies have been carried out to expand the classic structure {Fe(pz)[MII(CN)4]} (M = Ni, Pd, Pt) to get larger cavities, but the resulting compounds often showed a poor magnetic behavior. In this work, we present wide-mesh-size spin-switching Hofmann-type networks based on tetrakis-cyanoacetylides synthesized with a newly developed method, resulting in compounds with the general formula {Fe(pz)[M(C3N)4]} (M=Ni, Pd, Pt). The compounds were characterized in their structural, magnetic, and spectroscopic properties. They present 5-fold larger cavities and a drastic increase in porosity. The desired hysteretic and guest-dependent spin-crossover behavior is retained, and in situ chemo-switching of the spin state and the memory effect are also observed. | 10.1021/acs.inorgchem.4c02732 | [
[
"Willi",
"Zeni"
],
[
"Danny",
"Müller"
],
[
"Werner",
"Artner"
],
[
"Gerald",
"Giester"
],
[
"Michael",
"Reissner"
],
[
"Peter",
"Weinberger"
]
] |
Hydroxylation of an ultrathin Co3O4(111) film on Ir(100) studied by in situ ambient pressure XPS and DFT | In the present work, we have studied the interaction of water with spinel cobalt oxide (Co3O4), an effect which has been considered a major cause of its catalytic deactivation. Employing a Co3O4(111) model thin film grown on Ir(100) in (ultra)high vacuum, and ambient pressure X-ray photoelectron spectroscopy (APXPS), hydroxylation in 0.5 mbar H2O vapor at room temperature was monitored in real time. The surface hydroxyl (OH) coverage was determined via two different models based (i) on the termination of a pristine and OH-covered Co3O4(111) surface as derived from density functional theory (DFT) calculations, and (ii) on a homogeneous cobalt oxyhydroxide (CoO(OH)) overlayer. Langmuir pseudo-second-order kinetics were applied to characterize the OH evolution with time, suggesting two regimes of chemisorption at the mosaic-like Co3O4(111) film: (i) plateaus, which were quickly saturated by OH, followed by (ii) slow hydroxylation in the “cracks” of the thin film. H2O dissociation and OH formation, blocking exposed Co²? ions and additionally consuming surface lattice oxygen, respectively, may thus account for catalyst deactivation by H2O traces in reactive feeds. | 10.1016/j.susc.2024.122618 | [
[
"Thomas",
"Haunold"
],
[
"Krešimir",
"Anić"
],
[
"Alexander",
"Genest"
],
[
"Christoph",
"Rameshan"
],
[
"Matteo",
"Roiaz"
],
[
"Hao",
"Li"
],
[
"Thomas",
"Wicht"
],
[
"Jan",
"Knudsen"
],
[
"Günther",
"Rupprech... |
Alkene Isomerization Catalyzed by a Mn(I) Bisphosphine Borohydride Complex | An additive-free manganese-catalyzed isomerization of terminal alkenes to internal alkenes is described. This reaction is implementing an inexpensive nonprecious metal catalyst. The most efficient catalyst is the borohydride complex cis-[Mn(dippe)(CO)2(?2-BH4)]. This catalyst operates at room temperature, with a catalyst loading of 2.5 mol %. A variety of terminal alkenes is effectively and selectively transformed into the respective internal E-alkenes. Preliminary results show chain-walking isomerization at an elevated temperature. Mechanistic studies were carried out, including stoichiometric reactions and in situ NMR analysis. These experiments are flanked by computational studies. Based on these, the catalytic process is initiated by the liberation of “BH3” as a THF adduct. The catalytic process is initiated by double bond insertion into an M-H species, leading to an alkyl metal intermediate, followed by ß-hydride elimination at the opposite position to afford the isomerization product. | 10.1021/acscatal.4c03364 | [
[
"Ines",
"Blaha"
],
[
"Stefan",
"Weber"
],
[
"Robin",
"Dülger"
],
[
"Luis F.",
"Veiros"
],
[
"Karl",
"Kirchner"
]
] |
Development of a defined medium for the heterotrophic cultivation of Metallosphaera sedula | The heterotrophic cultivation of extremophilic archaea still heavily relies on complex media. However, complex media are associated with unknown composition, high batch-to-batch variability, potential inhibiting and interfering components, as well as regulatory challenges, hampering advancements of extremophilic archaea in genetic engineering and bioprocessing. For Metallosphaera sedula, a widely studied organism for biomining and bioremediation and a potential production host for archaeal ether lipids, efforts to find defined cultivation conditions have still been unsuccessful. This study describes the development of a novel chemically defined growth medium for M. sedula. Initial experiments with commonly used complex casein-derived media sources deciphered Casamino Acids as the most suitable foundation for further development. The imitation of the amino acid composition of Casamino Acids in basal Brock medium delivered the first chemically defined medium. We could further simplify the medium to 5 amino acids based on the respective specific substrate uptake rates. This first defined cultivation medium for M. sedula allows advanced genetic engineering and more controlled bioprocess development approaches for this highly interesting archaeon. | 10.1007/s00792-024-01348-0 | [
[
"Viktor Laurin",
"Sedlmayr"
],
[
"Maximilian",
"Luger"
],
[
"Ernst",
"Pittenauer"
],
[
"Martina",
"Marchetti-Deschmann"
],
[
"Laura",
"Kronlachner"
],
[
"Andreas",
"Limbeck"
],
[
"Philipp",
"Raunjak"
],
[
"Julian",
"Quehen... |
Thermal conductivity reduction in highly-doped cubic SiC by phonon-defect and phonon-electron scattering | We calculate the thermal conductivity (?) of highly N- and B-doped cubic silicon carbide (SiC) with defect concentrations (Cdef) from 1016 to 1021 cm-3 and compare the relative importance of the extrinsic phonon-electron and phonon-defect scattering mechanisms. Whereas phonon-electron scattering dominates over phonon-defect scattering at low Cdef up to about 1020 cm-3 at room temperature in N-doped SiC, phonon-defect scattering determines the thermal conductivity reduction in the B-doped case. This strong contrast between the electron- and hole-doped cases is related to the much higher ionization energy of B acceptors as compared to that of N donors, and to the resonant scattering caused by B substitution, not present for the N impurity. The similar features can be found in hexagonal phase 4H–SiC. Our results highlight the importance of considering the phonon-electron scattering mechanism together with other phonon scattering processes when calculating the thermal conductivity of doped semiconductors. | 10.1016/j.mtphys.2024.101346 | [
[
"Guijian",
"Pang"
],
[
"Fanchen",
"Meng"
],
[
"Yani",
"Chen"
],
[
"Ankita",
"Katre"
],
[
"Jesús",
"Carrete"
],
[
"Bonny",
"Dongre"
],
[
"Georg K.H.",
"Madsen"
],
[
"Natalio",
"Mingo"
],
[
"Wu",
"Li"
]
] |
Simultaneous path weak-measurements in neutron interferometry | The statistical properties of the detection events constituting the interference fringes at the output of an interferometer are well-known. Nevertheless, there is still no unified view of what is happening to a quantum system inside an interferometer. Strong measurements of path operators destroy the interference effect. In weak measurements, an observable is weakly coupled to a pointer system and the resulting weak values quantify the observable by minimally disturbing the system. Previous which-way experiments with weak measurements could extract either the real or imaginary part of a single weak value with each ensemble. Here, we present the simultaneous full complex quantification of two path weak values with a single ensemble in a Mach-Zehnder neutron interferometer. Magnetic fields, oscillating with different frequencies, change the energy state in each interferometer path. The time-dependent phase between the energy states distinctly marks each path. The resulting beating intensity modulation at the interferometer output gives both path weak values. For the present experiment, the weak values' absolute value and phase directly describe the observed amplitude and phase of the intensity modulation. | 10.1038/s41598-024-76167-6 | [
[
"Armin",
"Danner"
],
[
"Ismaele V.",
"Masiello"
],
[
"Andreas",
"Dvorak"
],
[
"Wenzel",
"Kersten"
],
[
"Hartmut",
"Lemmel"
],
[
"Richard",
"Wagner"
],
[
"Yuji",
"Hasegawa"
]
] |
Overcomplete intermediate representation of two-particle Green's functions and its relation to partial spectral functions | Two-particle response functions are a centerpiece of both experimental and theoretical quantum many-body physics. Yet, due to their size and discontinuity structure, they are challenging to handle numerically. Recently, two advances were made to tackle this problem: first, the overcomplete intermediate representation (OIR), which provides a highly efficient compression of Green's functions in imaginary frequency, and second, partial spectral functions (PSFs), which allow for an efficient evaluation in real frequency. We show that there is a two-to-one correspondence between PSFs and OIR coefficients and exploit this fact to construct the OIR for three-or-more-particle propagators. We then use OIR to fit and compress imaginary-frequency data obtained from the numerical renormalization group (NRG), reaching a compression ratio of more than 400. Finally, we attempt to match the OIR data to partial Green's functions from NRG. Due to the overcompleteness, we achieve only qualitative agreement. | 10.1103/PhysRevResearch.6.043228 | [
[
"Selina",
"Dirnböck"
],
[
"Seung-Sup B.",
"Lee"
],
[
"Fabian B.",
"Kugler"
],
[
"Sebastian",
"Huber"
],
[
"Jan",
"von Delft"
],
[
"Karsten",
"Held"
],
[
"Markus",
"Wallerberger"
]
] |
High entropy alloys (FeCoNi)0.75Cr0.25-xCux – thermal stability and physical properties | The paper reports on the phase stability of the (FeCoNi)0.75Cr0.25-xCux HEA system with equimolar ratio of Fe, Co and Ni by differential scanning calorimetry (DSC) and measurements of physicochemical properties: density, electrical resistivity, Seebeck coefficient, thermal conductivity, and magnetic behaviour in a broad temperature region as well as hardness and elastic modulus at room temperature as a function of the gradual substitution of chromium by copper in a series of (FeCoNi)0.75Cr0.25-xCux alloys with different mole fraction of Cu (x = 0, 0.05, 0.1, 0.15 and 0.2). DSC measurements showed that all alloys are thermally stable. Increasing content of Cu was found (i) to increase the formation of a fcc Cu-rich phase, (ii) to strengthen ferromagnetic interactions, resulting in rising ordered magnetic moments, as well as in growing ferromagnetic transition temperatures, and (iii) to distinctly change physical properties like electrical resistivity, thermal expansion, and mechanical properties. Experimental data regarding the phase stability are supported by CALPHAD calculations. | 10.1016/j.jallcom.2024.174628 | [
[
"Pavel",
"Brož"
],
[
"Jan",
"Vřešťál"
],
[
"Jiří",
"Sopoušek"
],
[
"Karel",
"Weiss"
],
[
"Jiří",
"Buršík"
],
[
"Vilma",
"Buršíková"
],
[
"Antonín",
"Záděra"
],
[
"Peter",
"Müller"
],
[
"Jan",
"Čupera"
],
[
... |
CO‐Induced Dimer Decay Responsible for Gem‐Dicarbonyl Formation on a Model Single‐Atom Catalyst | The ability to coordinate multiple reactants at the same active site is important for the wide-spread applicability of single-atom catalysis. Model catalysts are ideal to investigate the link between active site geometry and reactant binding, because the structure of single-crystal surfaces can be precisely determined, the adsorbates imaged by scanning tunneling microscopy (STM), and direct comparisons made to density functional theory. In this study, we follow the evolution of Rh1 adatoms and minority Rh2 dimers on Fe3O4(001) during exposure to CO using time-lapse STM at room temperature. CO adsorption at Rh1 sites results exclusively in stable Rh1CO monocarbonyls, because the Rh atom adapts its coordination to create a stable pseudo-square planar environment. Rh1(CO)2 gem-dicarbonyl species are also observed, but these form exclusively through the breakup of Rh2 dimers via an unstable Rh2(CO)3 intermediate. Overall, our results illustrate how minority species invisible to area-averaging spectra can play an important role in catalytic systems, and show that the decomposition of dimers or small clusters can be an avenue to produce reactive, metastable configurations in single-atom catalysis. | 10.1002/anie.202317347 | [
[
"Chunlei",
"Wang"
],
[
"Panukorn",
"Sombut"
],
[
"Lena",
"Puntscher"
],
[
"Zdenek",
"Jakub"
],
[
"Matthias",
"Meier"
],
[
"Jiri",
"Pavelec"
],
[
"Roland",
"Bliem"
],
[
"Michael",
"Schmid"
],
[
"Ulrike",
"Diebol... |
Magnets for a Muon Collider—Needs and Plans | We describe the magnet challenges for a Muon Collider, an exciting option considered for the future of particle physics at the energy frontier. Starting from the comprehensive work performed by the US Muon Accelerator Program, we have reviewed the performance specifications dictated by beam physics and the operating conditions to satisfy the accelerator needs. Among the many magnets that make up a muon collider, we have identified four systems that represent well the envelope of challenges: the target and capture solenoid, the final cooling solenoid, the accelerator dipoles and the collider dipoles. These systems provide focus for the development of novel concepts, largely based on HTS for reasons of performance, cost and sustainability. After giving a consolidated overview of the needs for the magnet systems, we describe here the basic technology options considered, and the plan for design and development activities. | 10.1109/TASC.2024.3382069 | [
[
"L.",
"Bottura"
],
[
"C.",
"Accettura"
],
[
"N.",
"Amemiya"
],
[
"B.",
"Auchmann"
],
[
"J.S.",
"Berg"
],
[
"A.",
"Bersani"
],
[
"A.",
"Bertarelli"
],
[
"F.",
"Boattini"
],
[
"B.",
"Bordini"
],
[
"P.",
... |
Photon-efficient optical tweezers via wavefront shaping | Optical tweezers enable noncontact trapping of microscale objects using light. It is not known how tightly it is possible to three-dimensionally (3D) trap microparticles with a given photon budget. Reaching this elusive limit would enable maximally stiff particle trapping for precision measurements on the nanoscale and photon-efficient tweezing of light-sensitive objects. Here, we customize the shape of light fields to suit specific particles, with the aim of optimizing trapping stiffness in 3D. We show, theoretically, that the confinement volume of microspheres held in sculpted optical traps can be reduced by one to two orders of magnitude. Experimentally, we use a wavefront shaping-inspired strategy to passively suppress the Brownian fluctuations of microspheres in every direction concurrently, demonstrating order-of-magnitude reductions in their confinement volumes. Our work paves the way toward the fundamental limits of optical control over the mesoscopic realm. | 10.1126/sciadv.adi7792 | [
[
"Unė G.",
"Būtaitė"
],
[
"Christina",
"Sharp"
],
[
"Michael",
"Horodynski"
],
[
"Graham M.",
"Gibson"
],
[
"Miles J.",
"Padgett"
],
[
"Stefan",
"Rotter"
],
[
"Jonathan M.",
"Taylor"
],
[
"David B.",
"Phillips"
]
] |
One-loop partition function of gravity with leaky boundary conditions | Leaky boundary conditions in asymptotically AdS spacetimes are relevant to discuss black hole evaporation and the evolution of the Page curve via the island formula. We explore the consequences of leaky boundary conditions on the one-loop partition function of gravity. We focus on JT gravity minimally coupled to a scalar field whose normalizable and non-normalizable modes are both turned on, allowing for leakiness through the AdS boundary. Classically, this yields a flux-balance law relating the scalar news to the time derivative of the mass. Semi-classically, we argue that the usual diffeomorphism-invariant measure is ill-defined, suggesting that the area-non-preserving diffeomorphisms are broken at one loop. We calculate the associated anomaly and its implication on the gravitational Gauss law. Finally, we generalize our arguments to higher dimensions and dS. | 10.1007/JHEP02(2024)080 | [
[
"Daniel",
"Grumiller"
],
[
"Romain",
"Ruzziconi"
],
[
"Céline",
"Zwikel"
]
] |
Resolving the local distortions of Ising-like moments in magnetoelectric Ho-doped langasite | The magnetic properties of Ho-doped langasites (La:Ho)33G?a5?Si?O14 are dominated by the Ising-like magnetic moments of the H?o³? ions. In their saturated regime, the induced magnetic state breaks both time and space inversion symmetries, leading to a linear magnetoelectric effect. However, due to distortions induced by a shared Ga/Si occupancy of the 2??? sites, resolving the microscopic nature of the magnetic configuration remains a difficult task. Here, we combine polarized neutron diffraction and angular-dependent magnetization experiments to determine the local distortions of the H?o³? magnetic moments in doped langasites (L?a1???H?o?)3?G?a55Si?O14 with ??˜0.015 and 0.045. We propose a model for a field-induced magnetic configuration with arbitrary orientations of the local Ising axis of H?o³? in distorted positions. The operations of broken local ??2 symmetry and rotations around the trigonal ??3 axis connect different sites, restoring the global ???321 symmetry of the crystal and simplifying the description of the magnetic properties. The superposition of two distorted H?o³? positions connected by ??2 symmetry determines the local magnetic susceptibility tensor, which no longer appears Ising-like at low fields. | 10.1103/PhysRevB.109.214433 | [
[
"A. Yu.",
"Tikhanovskii"
],
[
"V. Yu.",
"Ivanov"
],
[
"A. M.",
"Kuzmenko"
],
[
"A.",
"Stunault"
],
[
"O.",
"Fabelo"
],
[
"E.",
"Ressouche"
],
[
"V.",
"Simonet"
],
[
"R.",
"Ballou"
],
[
"I. A.",
"Kibalin"
],
... |
Reanalysis of the
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>β</mml:mi><mml:mo>−</mml:mo><mml:msub><mml:mrow><mml:mover accent="true"><mml:mrow><mml:mi>ν</mml:mi></mml:mrow><mml:mrow><mml:mo stretchy="false">¯</mml:mo></mml:mrow></mml:mover></mml:mrow><mml:mrow><mml:mi>e</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>
Angular Correlation Measurement from the aSPECT Experiment with New Constraints on Fierz Interference | On the basis of revisions of some of the systematic errors, we reanalyzed the electron-antineutrino angular correlation (a coefficient) in free neutron decay inferred from the recoil energy spectrum of the protons which are detected in 4p by the aSPECT spectrometer. With a=-0.104?02(82) the new value differs only marginally from the one published in 2020. The experiment also has sensitivity to b, the Fierz interference term. From a correlated (b,a) fit to the proton recoil spectrum, we derive a limit of b=-0.0098(193) which translates into a somewhat improved 90% confidence interval region of -0.041=b=0.022 on this hypothetical term. Tighter constraints on b can be set from a combined [shown as superscript (c)] analysis of the PERKEO III (ß asymmetry) and aSPECT measurement which suggests a finite value of b with b(c)=-0.0181±0.0065 deviating by 2.82s from the standard model. | 10.1103/PhysRevLett.132.102501 | [
[
"M.",
"Beck"
],
[
"W.",
"Heil"
],
[
"Ch.",
"Schmidt"
],
[
"S.",
"Baeßler"
],
[
"F.",
"Glück"
],
[
"G.",
"Konrad"
],
[
"U.",
"Schmidt"
]
] |
A plastic scintillation muon veto for sub-Kelvin temperatures | Rare-event search experiments located on-surface, such as short-baseline reactor neutrino experiments, are often limited by muon-induced background events. Highly efficient muon vetos are essential to reduce the detector background and to reach the sensitivity goals. We demonstrate the feasibility of deploying organic plastic scintillators at sub-Kelvin temperatures. For the NUCLEUS experiment, we developed a cryogenic muon veto equipped with wavelength shifting fibers and a silicon photo multiplier operating inside a dilution refrigerator. The achievable compactness of cryostat-internal integration is a key factor in keeping the muon rate to a minimum while maximizing coverage. The thermal and light output properties of a plastic scintillation detector were examined. We report first data on the thermal conductivity and heat capacity of the polystyrene-based scintillator UPS-923A over a wide range of temperatures extending below one Kelvin. The light output was measured down to 0.8 K and observed to increase by a factor of 1.61 ± 0.05 compared to 300 K. The development of an organic plastic scintillation muon veto operating in sub-Kelvin temperature environments opens new perspectives for rare-event searches with cryogenic detectors at sites lacking substantial overburden. | 10.1140/epjc/s10052-023-12375-0 | [
[
"A.",
"Erhart"
],
[
"V.",
"Wagner"
],
[
"A.",
"Wex"
],
[
"C.",
"Goupy"
],
[
"D.",
"Lhuillier"
],
[
"E.",
"Namuth"
],
[
"C.",
"Nones"
],
[
"R.",
"Rogly"
],
[
"V.",
"Savu"
],
[
"M.",
"Schwarz"
],
... |
High-resolution cross section measurements for neutron interactions on $$^{89}$$Y with incident neutron energies up to 95 keV | The cross section of the 8?Y(n,gamma) reaction has important implications in nuclear astrophysics and for advanced nuclear technology. Given its neutron magic number N = 50 and a consequent small neutron capture crosssection,8?Y represents one of the key nuclides for the stellars-process. It acts as a bottleneck in the neutron capture chain between the Fe seed and the heavier elements. Moreover, it is located at the overlapping region, where both the weak and mains-process components take place.8?Y, the only stable yttrium isotope, is also used in innovative nuclear reactors. Neutron capture and transmission measurements were per-formed at the time-of-flight facilities n_TOF at CERN and GELINA at JRC-Geel. Resonance parameters of individual resonances were extracted from a resonance analysis of the experimental transmission and capture yields, up to a neutron incident energy of 95 keV. Even though a comparison with results reported in the literature shows differences in resonance parameters, the present data are consistent with the Maxwellian averaged cross section suggested by the astro-physical database KADoNiS. | 10.1140/epja/s10050-024-01243-4 | [
[
"G.",
"Tagliente"
],
[
"P. M.",
"Milazzo"
],
[
"C.",
"Paradela"
],
[
"S.",
"Kopecky"
],
[
"D.",
"Vescovi"
],
[
"G.",
"Alaerts"
],
[
"L. A.",
"Damone"
],
[
"J.",
"Heyse"
],
[
"M.",
"Krtička"
],
[
"P.",
... |
A Segmented Total Energy Detector (sTED) optimized for (n, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si80.svg" display="inline" id="d1e1234"><mml:mi>γ</mml:mi></mml:math>) cross-section measurements at n_TOF EAR2 | The neutron time-of-flight facility n_TOF at CERN is a spallation source dedicated to measurements of neutroninduced reaction cross-sections of interest in nuclear technologies, astrophysics, and other applications. Since 2014, Experimental ARea 2 (EAR2) is operational and delivers a neutron fluence of similar to 4 center dot 10(7) neutrons per nominal proton pulse, which is similar to 50 times higher than the one of Experimental ARea 1 (EAR1) of similar to 8 center dot 10(5) neutrons per pulse. The high neutron flux at EAR2 results in high counting rates in the detectors that challenged the previously existing capture detection systems. For this reason, a Segmented Total Energy Detector (sTED) has been developed to overcome the limitations in the detector's response, by reducing the active volume per module and by using a photo-multiplier (PMT) optimized for high counting rates. This paper presents the main characteristics of the sTED, including energy and time resolution, response to gamma-rays, and provides as well details of the use of the Pulse Height Weighting Technique (PHWT) with this detector. The sTED has been validated to perform neutron-capture cross-section measurements in EAR2 in the neutron energy range from thermal up to at least 400 keV. The detector has already been successfully used in several measurements at n_TOF EAR2. | 10.1016/j.radphyschem.2024.111525 | [
[
"V.",
"Alcayne"
],
[
"D.",
"Cano-Ott"
],
[
"J.",
"Garcia"
],
[
"E.",
"González-Romero"
],
[
"T.",
"Martínez"
],
[
"A. Pérez de",
"Rada"
],
[
"J.",
"Plaza"
],
[
"A.",
"Sánchez-Caballero"
],
[
"J.",
"Balibrea-Cor... |
Optical transmission enhancement of ionic crystals via superionic fluoride transfer: Growing VUV-transparent radioactive crystals | The 8-eV first nuclear excited state in ²²?Th is a candidate for implementing a nuclear clock. Doping ²²?Th into ionic crystals such as CaF2 is expected to suppress nonradiative decay, enabling nuclear spectroscopy and the realization of a solid-state optical clock. Yet, the inherent radioactivity of ²²?Th prohibits the growth of high-quality single crystals with high ²²?Th concentration; radiolysis causes fluoride loss, increasing absorption at 8eV. These radioactively doped crystals are thus a unique material for which a deeper analysis of the physical effects of radioactivity on growth, crystal structure, and electronic properties is presented. Following the analysis, we overcome the increase in absorption at 8eV by annealing ²²?Th-doped CaF2 at 1250°C in CF4. This technique allows to adjust the fluoride content without crystal melting, preserving its single-crystal structure. Superionic state annealing ensures rapid fluoride distribution, creating fully transparent and radiation-hard crystals. This approach enables control over the charge state of dopants, which can be used in deep-UV optics, laser crystals, scintillators, and nuclear clocks. | 10.1103/PhysRevB.109.094111 | [
[
"Kjeld",
"Beeks"
],
[
"Tomas",
"Sikorsky"
],
[
"Fabian",
"Schaden"
],
[
"Martin",
"Pressler"
],
[
"Felix",
"Schneider"
],
[
"Björn N.",
"Koch"
],
[
"Thomas",
"Pronebner"
],
[
"David",
"Werban"
],
[
"Niyusha",
"... |
Laser Excitation of the Th-229 Nucleus | The 8.4 eV nuclear isomer state in Th-229 is resonantly excited in Th-doped CaF2 crystals using a tabletop tunable laser system. A resonance fluorescence signal is observed in two crystals with different Th-229 dopant concentrations, while it is absent in a control experiment using Th-232. The nuclear resonance for the Th4? ions in Th:CaF2 is measured at the wavelength 148.3821(5) nm, frequency 2020.409(7) THz, and the fluorescence lifetime in the crystal is 630(15) s, corresponding to an isomer half-life of 1740(50) s for a nucleus isolated in vacuum. These results pave the way toward Th-229 nuclear laser spectroscopy and realizing optical nuclear clocks. | 10.1103/PhysRevLett.132.182501 | [
[
"J.",
"Tiedau"
],
[
"M. V.",
"Okhapkin"
],
[
"K.",
"Zhang"
],
[
"J.",
"Thielking"
],
[
"G.",
"Zitzer"
],
[
"E.",
"Peik"
],
[
"F.",
"Schaden"
],
[
"T.",
"Pronebner"
],
[
"I.",
"Morawetz"
],
[
"L. Toscani... |
Controlling 229Th isomeric state population in a VUV transparent crystal | The radioisotope thorium-229 (²²?Th) is renowned for its extraordinarily low-energy, long-lived nuclear first-excited state. This isomeric state can be excited by vacuum ultraviolet (VUV) lasers and ²²?Th has been proposed as a reference transition for ultra-precise nuclear clocks. To assess the feasibility and performance of the nuclear clock concept, time-controlled excitation and depopulation of the ²²?Th isomer are imperative. Here we report the population of the ²²?Th isomeric state through resonant X-ray pumping and detection of the radiative decay in a VUV transparent ²²?Th-doped CaF2 crystal. The decay half-life is measured to 447(25)?s, with a transition wavelength of 148.18(42)?nm and a radiative decay fraction consistent with unity. Furthermore, we report a new "X-ray quenching" effect which allows to de-populate the isomer on demand and effectively reduce the half-life. Such controlled quenching can be used to significantly speed up the interrogation cycle in future nuclear clock schemes. | 10.1038/s41467-024-49631-0 | [
[
"Takahiro",
"Hiraki"
],
[
"Koichi",
"Okai"
],
[
"Michael",
"Bartokos"
],
[
"Kjeld",
"Beeks"
],
[
"Hiroyuki",
"Fujimoto"
],
[
"Yuta",
"Fukunaga"
],
[
"Hiromitsu",
"Haba"
],
[
"Yoshitaka",
"Kasamatsu"
],
[
"Shinji",
... |
Frequency ratio of the 229mTh nuclear isomeric transition and the 87Sr atomic clock | Optical atomic clocks1,2 use electronic energy levels to precisely keep track of time. A clock based on nuclear energy levels promises a next-generation platform for precision metrology and fundamental physics studies. Thorium-229 nuclei exhibit a uniquely low-energy nuclear transition within reach of state-of-the-art vacuum ultraviolet (VUV) laser light sources and have, therefore, been proposed for construction of a nuclear clock3,4. However, quantum-state-resolved spectroscopy of the 229mTh isomer to determine the underlying nuclear structure and establish a direct frequency connection with existing atomic clocks has yet to be performed. Here, we use a VUV frequency comb to directly excite the narrow 229Th nuclear clock transition in a solid-state CaF2 host material and determine the absolute transition frequency. We stabilize the fundamental frequency comb to the JILA 87Sr clock2 and coherently upconvert the fundamental to its seventh harmonic in the VUV range by using a femtosecond enhancement cavity. This VUV comb establishes a frequency link between nuclear and electronic energy levels and allows us to directly measure the frequency ratio of the 229Th nuclear clock transition and the 87Sr atomic clock. We also precisely measure the nuclear quadrupole splittings and extract intrinsic properties of the isomer. These results mark the start of nuclear-based solid-state optical clocks and demonstrate the first comparison, to our knowledge, of nuclear and atomic clocks for fundamental physics studies. This work represents a confluence of precision metrology, ultrafast strong-field physics, nuclear physics and fundamental physics. | 10.1038/s41586-024-07839-6 | [
[
"Chuankun",
"Zhang"
],
[
"Tian",
"Ooi"
],
[
"Jacob S.",
"Higgins"
],
[
"Jack F.",
"Doyle"
],
[
"Lars",
"von der Wense"
],
[
"Kjeld",
"Beeks"
],
[
"Adrian",
"Leitner"
],
[
"Georgy A.",
"Kazakov"
],
[
"Peng",
"Li... |
Effect of iodine species on biofortification of iodine in cabbage plants cultivated in hydroponic cultures | Iodine is an essential trace element in the human diet because it is involved in the synthesis of thyroid hormones. Iodine deficiency affects over 2.2 billion people worldwide, making it a significant challenge to find plant-based sources of iodine that meet the recommended daily intake of this trace element. In this study, cabbage plants were cultivated in a hydroponic system containing iodine at concentrations ranging from 0.01 to 1.0 mg/L in the form of potassium iodide or potassium iodate. During the experiments, plant physiological parameters, biomass production, and concentration changes of iodine and selected microelements in different plant parts were investigated. In addition, the oxidation state of the accumulated iodine in root samples was determined. Results showed that iodine addition had no effect on photosynthetic efficiency and chlorophyll content. Iodide treatment did not considerably stimulate biomass production but iodate treatment increased it at concentrations less than 0.5 mg/L. Increasing iodine concentrations in the nutrient solutions increased iodine content in all plant parts; however, the iodide treatment was 2-7 times more efficient than the iodate treatment. It was concluded, that iodide addition was more favourable on the target element accumulation, however, it should be highlighted that application of this chemical form in nutrient solution decreased the concetrations of selected micoelement concentration comparing with the control plants. It was established that iodate was reduced to iodide during its uptake in cabbage roots, which means that independently from the oxidation number of iodine (+?5, -?1) applied in the nutrient solutions, the reduced form of target element was transported to the aerial and edible tissues. | 10.1038/s41598-024-66575-z | [
[
"Péter",
"Dobosy"
],
[
"Hoang Thi Phuong",
"Nguyen"
],
[
"Gyula",
"Záray"
],
[
"Christina",
"Streli"
],
[
"Dieter",
"Ingerle"
],
[
"Philipp",
"Ziegler"
],
[
"Martin",
"Radtke"
],
[
"Ana Guilherme",
"Buzanich"
],
[
... |
Hydrogen crystals reduce dissipation in superconducting resonators | We show that the internal quality factors of high-impedance superconducting resonators made of granular aluminum can be improved by coating them with micrometric films of solid parahydrogen molecular crystals. We attribute the average measured ˜8% reduction in dissipation to the absorption of stray terahertz radiation at the crystal-resonator interface and the subsequent dissipation of its energy in the form of phonons below the pair-breaking gap. Our results prove that contrary to expectations, replacing the vacuum dielectric atop a superconducting resonator can be beneficial, thanks to the added protection against Cooper pair-braking terahertz radiation. Moreover, at the level of internal quality factors in the 105 range, the hydrogen crystal does not introduce additional losses, which is promising for embedding impurities to couple to superconducting thin-film devices in hybrid quantum architectures. | 10.1103/PhysRevB.109.054503 | [
[
"Francesco",
"Valenti"
],
[
"Andrew N.",
"Kanagin"
],
[
"Andreas",
"Angerer"
],
[
"Luiza",
"Buimaga-Iarinca"
],
[
"Cristian",
"Morari"
],
[
"Jörg",
"Schmiedmayer"
],
[
"Ioan M.",
"Pop"
]
] |
A Vibration Decoupling System for TES Operation in the COSINUS Dry Dilution Refrigerator | COSINUS will be among the first underground experiments to operate Transition Edge Sensors in a dry dilution refrigerator, measuring temperature changes on the order of µK. A pulse tube cryocooler is used to cool down to 3K, trading simplified handling, by not using liquid noble gases, for an increased vibration noise level in the acoustic frequency range. As the signals measured with a TES are in the same frequency region, it is necessary to decouple the detectors from all possible noise sources. In COSINUS, a two-level passive decoupling system was developed and tested using piezo-based accelerometers. At the first level, the refrigerator is mechanically isolated from all external noise sources. For the second level an internal spring-based system was developed and tested on a mockup system. On the first level a reduction of the vibrational background up to a factor 4 below 10 Hz could be measured. On the second level a resonance frequency of 1.2 Hz with damping of higher frequencies was achieved. | 10.1007/s10909-024-03206-x | [
[
"M.",
"Kellermann"
],
[
"G.",
"Angloher"
],
[
"M. R.",
"Bharadawj"
],
[
"M.",
"Cababie"
],
[
"I.",
"Dafinei"
],
[
"N.",
"Di Marco"
],
[
"L.",
"Einfalt"
],
[
"F.",
"Ferroni"
],
[
"S.",
"Fichtinger"
],
[
... |
Detector Development for the CRESST Experiment | Recently low-mass dark matter direct searches have been hindered by a low-energy background, drastically reducing the physics reach of the experiments. In the CRESST-III experiment, this signal is characterised by a significant increase of events below 200 eV. As the origin of this background is still unknown, it became necessary to develop new detector designs to reach a better understanding of the observations. Within the CRESST collaboration, three new different detector layouts have been developed, and they are presented in this contribution. | 10.1007/s10909-024-03154-6 | [
[
"G.",
"Angloher"
],
[
"S.",
"Banik"
],
[
"G.",
"Benato"
],
[
"A.",
"Bento"
],
[
"A.",
"Bertolini"
],
[
"R.",
"Breier"
],
[
"C.",
"Bucci"
],
[
"J.",
"Burkhart"
],
[
"L.",
"Canonica"
],
[
"A.",
"D’Add... |
Test of lepton flavor universality in
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decays in proton-proton collisions at
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</mml:math> | A test of lepton flavor universality in B^± ? K^±µ^+µ^- and B^± ? K^±e^+e^- decays, as well as a_x000D_
measurement of differential and integrated branching fractions of a nonresonant_x000D_
B± ? K^±µ^+µ^- decay are presented. The analysis is made possible by a dedicated data set of_x000D_
proton-proton collisions at vs = 13TeV recorded in 2018, by the CMS experiment at the LHC,_x000D_
using a special high-rate data stream designed for collecting about 10 billion unbiased b hadron_x000D_
decays. The ratio of the branching fractions B(B^± ? K^±µ^+µ^-) to B(B^± ? K^±e^+e^-) is_x000D_
determined from the measured double ratio R(K) of these decays to the respective branching_x000D_
fractions of the B^± ? J/?K^± with J/? ? µ^+µ^- and e^+e^- decays, which allow for significant_x000D_
cancellation of systematic uncertainties. The ratio R(K) is measured in the range 1.1 < q^2 < 6.0 GeV^2, where q is the invariant mass of the lepton pair, and is found to be_x000D_
R(K) = 0.78^8{+0.47}_{-0.23}, in agreement with the standard model expectation R(K) ˜ 1. This_x000D_
measurement is limited by the statistical precision of the electron channel. The integrated branching fraction in the same q^2 range, B(B^± ? K^±µ^+µ^-) = (12.42 ± 0.68) × 10^{-8}, is consistent with the present world-average value and has a comparable precision. | 10.1088/1361-6633/ad4e65 | [
[
"The",
"CMS Collaboration"
]
] |
First experimental time-of-flight-based proton radiography using low gain avalanche diodes | Objective.Ion computed tomography (iCT) is an imaging modality for the direct determination of the relative stopping power (RSP) distribution within a patient's body. Usually, this is done by estimating the path and energy loss of ions traversing the scanned volume utilising a tracking system and a separate residual energy detector. This study, on the other hand, introduces the first experimental study of a novel iCT approach based on time-of-flight (TOF) measurements, the so-called Sandwich TOF-iCT concept, which in contrast to any other iCT systems, does not require a residual energy detector for the RSP determination.Approach.A small Sandwich TOF-iCT demonstrator was built based on low gain avalanche diodes (LGADs), which are 4D-tracking detectors that allow to simultaneously measure the particle position and time-of-arrival with a precision better than 100µm and 100 ps, respectively. Using this demonstrator, the material and energy-dependent TOF was measured for several homogeneous PMMA slabs in order to calibrate the acquired TOF against the corresponding water equivalent thickness (WET). With this calibration, two proton radiographs (pRads) of a small aluminium stair phantom were recorded at MedAustron using 83 MeV and 100.4 MeV protons.Main results.Due to the simplified WET calibration models used in this very first experimental study of this novel approach, the difference between the measured and theoretical WET ranged between 37.09% and 51.12%. Nevertheless, the first TOF-based pRad was successfully recorded showing that LGADs are suitable detector candidates for Sandwich TOF-iCT.Significance.While the system parameters and WET estimation algorithms require further optimization, this work was an important first step to realize Sandwich TOF-iCT. Due to its compact and cost-efficient design, Sandwich TOF-iCT has the potential to make iCT more feasible and attractive for clinical application, which, eventually, could enhance the treatment planning quality. | 10.1088/1361-6560/ad3326 | [
[
"Felix",
"Ulrich-Pur"
],
[
"Thomas",
"Bergauer"
],
[
"Tetyana",
"Galatyuk"
],
[
"Albert",
"Hirtl"
],
[
"Matthias",
"Kausel"
],
[
"Vadym",
"Kedych"
],
[
"Mladen",
"Kis"
],
[
"Yevhen",
"Kozymka"
],
[
"Wilhelm",
"... |
Measurements of azimuthal anisotropy of nonprompt D0 mesons in PbPb collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"><mml:msqrt><mml:mrow><mml:msub><mml:mrow><mml:mi>s</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="normal">NN</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:msqrt><mml:mo linebreak="goodbreak" linebreakstyle="after">=</mml:mo><mml:mn>5.02</mml:mn><mml:mspace width="0.2em"/><mml:mtext>TeV</mml:mtext></mml:math> | Measurements of the elliptic (??_2) and triangular (??_3) azimuthal anisotropy coefficients are presented for D^0 mesons produced in b hadron decays (nonprompt D^0 mesons) in lead-lead collisions at v??_{NN} = 5.02TeV. The results are compared with previously published charm meson anisotropies measured using prompt D^0 mesons. The data were collected with the CMS detector in 2018 with an integrated luminosity of 0.58 nb^{-1}. Azimuthal anisotropy is sensitive to the interactions of quarks with the hot and dense medium created in heavy ion collisions. Comparing results for prompt and nonprompt D^0 mesons can assist in understanding the mass dependence of these interactions. The nonprompt results show lower magnitudes of ??_2 and ??_3 and weaker dependences on the meson transverse momentum and collision centrality than those found for prompt D^0 mesons. The results are in agreement with theoretical predictions that include a mass dependence in the interactions of quarks with the medium. | 10.1016/j.physletb.2023.138389 | [
[
"A.",
"Tumasyan"
],
[
"W.",
"Adam"
],
[
"J.W.",
"Andrejkovic"
],
[
"T.",
"Bergauer"
],
[
"S.",
"Chatterjee"
],
[
"K.",
"Damanakis"
],
[
"M.",
"Dragicevic"
],
[
"A.",
"Escalante Del Valle"
],
[
"P.S.",
"Hussain"... |
Search for new Higgs bosons via same-sign top quark pair production in association with a jet in proton-proton collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt><mml:mo linebreak="goodbreak" linebreakstyle="after">=</mml:mo><mml:mn>13</mml:mn><mml:mspace width="0.2em"/><mml:mtext>TeV</mml:mtext></mml:math> | A search is presented for new Higgs bosons in proton-proton (pp) collision events in which a same-sign top quark pair is produced in association with a jet, via the pp ? tH/A ? tt\bar{c} and pp ? tH/A ? tt\bar{u} processes. Here, H and A represent the extra scalar and pseudoscalar boson, respectively, of the second Higgs doublet in the generalized_x000D_
two-Higgs-doublet model (g2HDM). The search is based on pp collision data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb^{-1}. Final states with a same-sign lepton pair in association with jets and missing transverse momentum are considered. New Higgs bosons in the 200–1000 GeV mass range and new Yukawa couplings between 0.1 and 1.0 are targeted in the search, for scenarios in which either H or A appear alone, or in which they coexist and interfere. No significant excess above the standard model prediction is observed. Exclusion limits are derived in the context of the g2HDM. | 10.1016/j.physletb.2024.138478 | [
[
"A.",
"Hayrapetyan"
],
[
"A.",
"Tumasyan"
],
[
"W.",
"Adam"
],
[
"J.W.",
"Andrejkovic"
],
[
"T.",
"Bergauer"
],
[
"S.",
"Chatterjee"
],
[
"K.",
"Damanakis"
],
[
"M.",
"Dragicevic"
],
[
"P.S.",
"Hussain"
],
... |
Search for the lepton flavor violating τ → 3μ decay in proton-proton collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt><mml:mo linebreak="goodbreak" linebreakstyle="after">=</mml:mo><mml:mn>13</mml:mn><mml:mspace width="0.2em"/><mml:mtext>TeV</mml:mtext></mml:math> | A search for the lepton flavor violating t ? 3µ decay is performed using proton-proton collision events at a center-of-mass energy of 13TeV collected by the CMS experiment at the LHC in 2017–2018, corresponding to an integrated luminosity of 97.7 fb^-1. Tau leptons produced in both heavy-flavor hadron and W boson decays are exploited in the analysis. No evidence for the decay is observed. The results of this search are combined with an earlier null result based on data collected in 2016 to obtain a total integrated luminosity of 131 fb^-1. The observed (expected) upper limits on the branching fraction B(t ? 3µ) at confidence levels of 90 and 95% are 2.9 ×10^-8 (2.4 ×10^-8) and 3.6 ×10^-8 (3.0 ×10^-8), respectively. | 10.1016/j.physletb.2024.138633 | [
[
"A.",
"Hayrapetyan"
],
[
"A.",
"Tumasyan"
],
[
"W.",
"Adam"
],
[
"J.W.",
"Andrejkovic"
],
[
"T.",
"Bergauer"
],
[
"S.",
"Chatterjee"
],
[
"K.",
"Damanakis"
],
[
"M.",
"Dragicevic"
],
[
"P.S.",
"Hussain"
],
... |
Study of azimuthal anisotropy of ϒ(1S) mesons in pPb collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"><mml:msqrt><mml:mrow><mml:msub><mml:mrow><mml:mi>s</mml:mi></mml:mrow><mml:mrow><mml:msub><mml:mrow/><mml:mrow><mml:mi mathvariant="normal">NN</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:msub></mml:mrow></mml:msqrt></mml:math> = 8.16 TeV | The azimuthal anisotropy of ?(1S) mesons in high-multiplicity proton-lead collisions is studied using data collected by the CMS experiment at a nucleon-nucleon center-of-mass energy of 8.16TeV. The ?(1S) mesons are reconstructed using their dimuon decay channel. The anisotropy is characterized by the second Fourier harmonic_x000D_
coefficients, found using a two-particle correlation technique, in which the ?(1S) mesons are correlated with charged hadrons. A large pseudorapidity gap is used to suppress short-range correlations. Nonflow contamination from the dijet background is removed using a low-multiplicity subtraction method, and the results are presented as a function of ?(1S) transverse momentum. The azimuthal anisotropies are smaller than those found for charmonia in proton-lead collisions at the same collision energy, but are consistent with values found for ?(1S) mesons in lead-lead interactions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. | 10.1016/j.physletb.2024.138518 | [
[
"A.",
"Tumasyan"
],
[
"W.",
"Adam"
],
[
"J.W.",
"Andrejkovic"
],
[
"T.",
"Bergauer"
],
[
"S.",
"Chatterjee"
],
[
"K.",
"Damanakis"
],
[
"M.",
"Dragicevic"
],
[
"A.",
"Escalante Del Valle"
],
[
"P.S.",
"Hussain"... |
Search for an exotic decay of the Higgs boson into a Z boson and a pseudoscalar particle in proton-proton collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt><mml:mo linebreak="goodbreak" linebreakstyle="after">=</mml:mo><mml:mn>13</mml:mn><mml:mrow><mml:mspace width="0.20em"/><mml:mtext>TeV</mml:mtext></mml:mrow></mml:math> | Asearch for an exotic decay of the Higgs boson to a Z boson and a light pseudoscalar particle (a), decaying to a pair of leptons and a pair of photons, respectively, is presented. The search is based on proton-proton collision data at a center-of-mass energy of v??=13 TeV, collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 138 fb^-1. The analysis probes pseudoscalar masses ??_a between 1 and 30GeV, leading to two pairs of well-isolated leptons and photons. Upper limits at 95% confidence level are set on the Higgs boson production cross section times its branching fraction to two leptons and two photons. The observed (expected) limits are in the range of 1.1–17.8 (1.7–17.9)fb within the probed ??a interval. An excess of data above the expected standard model background with a local (global) significance of 2.6 (1.3) standard deviations is observed for a mass hypothesis of ??_a =3 GeV. Limits on models involving axion-like particles, formulated as an effective field theory, are also reported. | 10.1016/j.physletb.2024.138582 | [
[
"A.",
"Hayrapetyan"
],
[
"A.",
"Tumasyan"
],
[
"W.",
"Adam"
],
[
"J.W.",
"Andrejkovic"
],
[
"T.",
"Bergauer"
],
[
"S.",
"Chatterjee"
],
[
"K.",
"Damanakis"
],
[
"M.",
"Dragicevic"
],
[
"A.",
"Escalante Del Vall... |
A multi-channel microfluidic platform based on human flavin-containing monooxygenase 3 for personalised medicine | Human flavin-containing monooxygenase 3 (FMO3) is a drug-metabolizing enzyme (DME) which is known to be highly polymorphic. Some of its polymorphic variants are associated with inter-individual differences that contribute to drug response. In order to measure these differences, the implementation of a quick and efficient in vitro assay is highly desirable. To this end, in this work a microfluidic immobilized enzyme reactor (µ-IMER) was developed with four separate serpentines where FMO3 and its two common polymorphic variants (V257M and E158K) were covalently immobilized via glutaraldehyde cross-linking in the presence of a polylysine coating. Computational fluid dynamics simulations were performed to calculate the selected substrate retention time in serpentines with different surface areas at various flow rates. The oxidation of tamoxifen, an anti-breast cancer drug, was used as a model reaction to characterize the new device in terms of available surface area for immobilization, channel coating, and applied flow rate. The highest amount of product was obtained when applying a 10 µL min?¹ flow rate on polylysine-coated serpentines with a surface area of 90 mm² each. Moreover, these conditions were used to test the device as a multi-enzymatic platform by simultaneously assessing the conversion of tamoxifen by FMO3 and its two polymorphic variants immobilized on different serpentines of the same chip. The results obtained demonstrate that the differences observed in the conversion of tamoxifen within the chip are similar to those already published (E158K > WT > V257M). Therefore, this microfluidic platform provides a feasible option for fabricating devices for personalised medicine. | 10.1039/d4ra01516a | [
[
"Melissa",
"De Angelis"
],
[
"Silvia",
"Schobesberger"
],
[
"Florian",
"Selinger"
],
[
"Viktor Laurin",
"Sedlmayr"
],
[
"Martin",
"Frauenlob"
],
[
"Orsola",
"Corcione"
],
[
"Shiman",
"Dong"
],
[
"Gianfranco",
"Gilardi"
]... |
Ligand engineering enhances (photo) electrocatalytic activity and stability of zeolitic imidazolate frameworks via in-situ surface reconstruction | The current limitations in utilizing metal-organic frameworks for (photo)electrochemical applications stem from their diminished electrochemical stability. In our study, we illustrate a method to bolster the activity and stability of (photo)electrocatalytically active metal-organic frameworks through ligand engineering. We synthesize four distinct mixed-ligand versions of zeolitic imidazolate framework-67, and conduct a comprehensive investigation into the structural evolution and self-reconstruction during electrocatalytic oxygen evolution reactions. In contrast to the conventional single-ligand ZIF, where the framework undergoes a complete transformation into CoOOH via a stepwise oxidation, the ligand-engineered zeolitic imidazolate frameworks manage to preserve the fundamental framework structure by in-situ forming a protective cobalt (oxy)hydroxide layer on the surface. This surface reconstruction facilitates both conductivity and catalytic activity by one order of magnitude and considerably enhances the (photo)electrochemical stability. This work highlights the vital role of ligand engineering for designing advanced and stable metal-organic frameworks for photo- and electrocatalysis. | 10.1038/s41467-024-53385-0 | [
[
"Zheao",
"Huang"
],
[
"Zhouzhou",
"Wang"
],
[
"Hannah",
"Rabl"
],
[
"Shaghayegh",
"Naghdi"
],
[
"Qiancheng",
"Zhou"
],
[
"Sabine",
"Schwarz"
],
[
"Dogukan Hazar",
"Apaydin"
],
[
"Ying",
"Yu"
],
[
"Dominik",
"Ed... |
Improving Spatial Resolution by Reinterpreting Dosage for Laser-Induced Breakdown Spectroscopy Imaging: Conceptualization and Limitations | Elemental imaging in laser-induced breakdown spectroscopy is usually performed by placing laser shots adjacent to each other on the sample surface without spatial overlap. Seeing that signal intensity is directly related to the amount of ablated material, this restricts either spatial resolution (for a given excitation efficiency) or sensitivity (when reducing the laser spot size). The experimental applicability of a concept involving the spatial overlapping of shots on the sample surface is investigated and compared to the conventional approach. By systematic choice of spacing between laser shots, spatial resolution can be improved to the single digit micrometer range for a given laser spot size. Signal intensity is found to be linearly dependent on the area ablated per shot, facilitating larger signal-to-background ratios with increased spot sizes. Owing to this, the presented approach is also employed to enhance signal intensity, while preserving spatial resolution. The applicability of the method is explored by analyzing samples with distinct thickness of the surface layer, allowing for the assessment of the concept's suitability for different sample types. | 10.1021/cbmi.4c00045 | [
[
"David Ken",
"Gibbs"
],
[
"Maximilian",
"Podsednik"
],
[
"Patrick",
"Tapler"
],
[
"Maximilian",
"Weiss"
],
[
"Alexander Karl",
"Opitz"
],
[
"Michael",
"Nelhiebel"
],
[
"Charles Derrick",
"Quarles Jr"
],
[
"Silvia",
"Larise... |
Lattice dynamics of the frustrated kagome compound Y-kapellasite | Studying the magnetic ground states of frustrated antiferromagnets provides unique insight into the stability of quantum spin liquids, even if the anticipated state is not realized toward T = 0. Particularly relevant are structural modifications setting in at temperatures where the magnetic correlations come into play. Here, we explore the lattice dynamics of Y-kapellasite [Y3Cu9(OH)19Cl8] single crystals by infrared spectroscopy in combination with ab initio calculations. We observe significant changes in the phonon spectra at T?=32 K that gradually evolve down to low temperatures. The increase in the number of phonon modes provides evidence for a lowering of symmetry, and we discuss several possibilities of crystal structure modifications. Our analysis also reveals that the structural variation involves exclusively H and O atoms, while the other atoms remain rather unaffected. An 8% redshift of the lowest-lying phonon mode upon cooling indicates strong magnetoelastic effects upon decoupling Cu-6f hexagons through the lattice vibrations. | 10.1103/PhysRevB.110.174445 | [
[
"P.",
"Doležal"
],
[
"T.",
"Biesner"
],
[
"Y.",
"Li"
],
[
"R.",
"Mathew Roy"
],
[
"S.",
"Roh"
],
[
"R.",
"Valentí"
],
[
"M.",
"Dressel"
],
[
"P.",
"Puphal"
],
[
"A.",
"Pustogow"
]
] |
Optical Shubnikov–de Haas oscillations in two-dimensional electron systems | We report on dynamic Shubnikov–de Haas (SdH) oscillations that are measured in the optical response, subterahertz transmittance of two-dimensional systems, and reveal two distinct types of oscillation nodes: “universal” nodes at integer ratios of radiation and cyclotron frequencies and “tunable” nodes at positions sensitive to all parameters of the structure. The nodes in both real and imaginary parts of the measured complex transmittance are analyzed using a dynamic version of the static Lifshitz-Kosevich formula. These results demonstrate that the node structure of the dynamic SdH oscillations provides an all-optical access to quantization- and interaction-induced renormalization effects, in addition to parameters one can obtain from the static SdH oscillations. | 10.1103/PhysRevResearch.6.L022027 | [
[
"M. L.",
"Savchenko"
],
[
"J.",
"Gospodarič"
],
[
"A.",
"Shuvaev"
],
[
"I. A.",
"Dmitriev"
],
[
"V.",
"Dziom"
],
[
"A. A.",
"Dobretsova"
],
[
"N. N.",
"Mikhailov"
],
[
"Z. D.",
"Kvon"
],
[
"A.",
"Pimenov"
]
] |
Digitalization of urban multi-energy systems – Advances in digital twin applications across life-cycle phases | Urban multi-energy systems (UMES) incorporating distributed energy resources are vital to future low-carbon energy systems. These systems demand complex solutions, including increased integration of renewables, improved efficiency through electrification, and exploitation of synergies via sector coupling across multiple sectors and infrastructures. Digitalization and the Internet of Things bring new opportunities for the design-build-operate workflow of the cyber-physical urban multi-energy systems. In this context, digital twins are expected to play a crucial role in managing the intricate integration of assets, systems, and actors within urban multi-energy systems. This review explores digital twin opportunities for urban multi-energy systems by first considering the challenges of urban multi energy systems. It then reviews recent advancements in digital twin architectures, energy system data categories, semantic ontologies, and data management solutions, addressing the growing data demands and modelling complexities. Digital twins provide an objective and comprehensive information base covering the entire design, operation, decommissioning, and reuse lifecycle phases, enhancing collaborative decision-making among stakeholders. This review also highlights that future research should focus on scaling digital twins to manage the complexities of urban environments. A key challenge remains in identifying standardized ontologies for seamless data exchange and interoperability between energy systems and sectors. As the technology matures, future research is required to explore the socio-economic and regulatory implications of digital twins, ensuring that the transition to smart energy systems is both technologically sound and socially equitable. The paper concludes by making a series of recommendations on how digital twins could be implemented for urban multi energy systems. | 10.1016/j.adapen.2024.100196 | [
[
"B.",
"Koirala"
],
[
"H.",
"Cai"
],
[
"F.",
"Khayatian"
],
[
"E.",
"Munoz"
],
[
"J.G.",
"An"
],
[
"R.",
"Mutschler"
],
[
"M.",
"Sulzer"
],
[
"C.",
"De Wolf"
],
[
"K.",
"Orehounig"
]
] |
Poly-β-hydroxybutyrate production by Synechocystis MT_a24 in a raceway pond using urban wastewater | Poly-ß-hydroxybutyrate (PHB) is a potential source of biodegradable plastics that are environmentally friendly due to their complete degradation to water and carbon dioxide. This study aimed to investigate PHB production in the cyanobacterium Synechocystis sp. PCC6714 MT_a24 in an outdoor bioreactor using urban wastewater as a sole nutrient source. The culture was grown in a thin-layer raceway pond with a working volume of 100 L, reaching a biomass density of up to 3.5 g L?¹ of cell dry weight (CDW). The maximum PHB content was found under nutrient-limiting conditions in the late stationary phase, reaching 23.7?±?2.2% PHB per CDW. These data are one of the highest reported for photosynthetic production of PHB by cyanobacteria, moreover using urban wastewater in pilot-scale cultivation which multiplies the potential of sustainable cultivation approaches. Contamination by grazers (Poterioochromonas malhamensis) was managed by culturing Synechocystis in a highly alkaline environment (pH about 10.5) which did not significantly affect the culture growth. Furthermore, the strain MT_a24 showed significant wastewater nutrient remediation removing about 72% of nitrogen and 67% of phosphorus. These trials demonstrate that the photosynthetic production of PHB by Synechocystis sp. PCC6714 MT_a24 in the outdoor thin-layer bioreactor using urban wastewater and ambient carbon dioxide. It shows a promising approach for the cost-effective and sustainable production of biodegradable carbon-negative plastics. KEY POINTS: • High PHB production by cyanobacteria in outdoor raceway pond • Urban wastewater used as a sole source of nutrients for phototrophic growth • Potential for cost-effective and sustainable production of biodegradable plastics. | 10.1007/s00253-023-12924-3 | [
[
"Tomáš",
"Grivalský"
],
[
"Gergely Ernő",
"Lakatos"
],
[
"Karolína",
"Štěrbová"
],
[
"João Artur Câmara",
"Manoel"
],
[
"Romana",
"Beloša"
],
[
"Petra",
"Divoká"
],
[
"Julian",
"Kopp"
],
[
"Ricarda",
"Kriechbaum"
],
[
... |
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