Pub Date : 2024-12-03DOI: 10.1038/s41587-024-02495-7
Proteolytic chimeras constructed from various bioactive modules can degrade either cytoplasmic or extracellular proteins, but their pharmacology faces challenges. Now, a protein degradation platform built with engineered platelets enables the targeted depletion of intracellular and extracellular proteins at hemorrhagic sites, addressing several limitations associated with proteolytic chimeras.
{"title":"Proteolytic platelets as targeted protein degraders","authors":"","doi":"10.1038/s41587-024-02495-7","DOIUrl":"https://doi.org/10.1038/s41587-024-02495-7","url":null,"abstract":"Proteolytic chimeras constructed from various bioactive modules can degrade either cytoplasmic or extracellular proteins, but their pharmacology faces challenges. Now, a protein degradation platform built with engineered platelets enables the targeted depletion of intracellular and extracellular proteins at hemorrhagic sites, addressing several limitations associated with proteolytic chimeras.","PeriodicalId":19084,"journal":{"name":"Nature biotechnology","volume":"13 1","pages":""},"PeriodicalIF":46.9,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-03DOI: 10.1021/acs.iecr.4c02244
Michael A. Denchy, Josh Kintzer, Tim Schmitt, Gavin Troop, Pradeep Balkhandia, Chien-Hua Chen, Devon Jensen
Metal powder-based additive manufacturing (AM) processes face a significant challenge with an increasing oxygen concentration (predominantly as surface oxides) in metal powders during reuse cycles. This increased surface oxidation, occurring at the high temperatures encountered by powders during the printing process, ultimately surpasses industry-acceptable quality limits. Powder bed fusion (PBF) AM processes deposit metal powders layer by layer, resulting in wasted feedstock, which can increase unit costs and have adverse environmental impacts. It is therefore essential to develop and optimize processes to enable the recycling and reuse of metal feedstock powders to establish sustainable AM processes industry wide. To address this challenge, we report the application of a novel low-temperature nonequilibrium hydrogen (H2) plasma- (HP-) based deoxidation process for efficient recycling and reuse of metal powder in AM processes. The technique involves the highly reactive species generated in a H2-fed low-pressure radio frequency (RF) plasma discharge dynamically interacting with oxidized powder in a quartz tube reactor, thereby reducing oxide content without adversely affecting particle size or morphology. In this study using a bronze copper–tin alloy (CuSn10) powder, a >60% reduction in oxide content was achieved through the HP treatment of oxidized CuSn10 powder samples at the 10 g/batch scale as measured via inert gas fusion (IGF), which is a significant improvement and well below the measured oxygen content of the as-received virgin CuSn10 powder. HP-treated powder was further characterized to determine treatment effect on powder morphology, bulk particle structure, and surface chemical composition via laser diffraction and dynamic imaging analysis, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. Initial demonstration of process scale-up showed a >50% reduction in oxide content at an increased batch size of 100 g/batch.
{"title":"Nonthermal Hydrogen Plasma Process for the Reuse of Metal Additive Manufacturing Feedstock Powder","authors":"Michael A. Denchy, Josh Kintzer, Tim Schmitt, Gavin Troop, Pradeep Balkhandia, Chien-Hua Chen, Devon Jensen","doi":"10.1021/acs.iecr.4c02244","DOIUrl":"https://doi.org/10.1021/acs.iecr.4c02244","url":null,"abstract":"Metal powder-based additive manufacturing (AM) processes face a significant challenge with an increasing oxygen concentration (predominantly as surface oxides) in metal powders during reuse cycles. This increased surface oxidation, occurring at the high temperatures encountered by powders during the printing process, ultimately surpasses industry-acceptable quality limits. Powder bed fusion (PBF) AM processes deposit metal powders layer by layer, resulting in wasted feedstock, which can increase unit costs and have adverse environmental impacts. It is therefore essential to develop and optimize processes to enable the recycling and reuse of metal feedstock powders to establish sustainable AM processes industry wide. To address this challenge, we report the application of a novel low-temperature nonequilibrium hydrogen (H<sub>2</sub>) plasma- (HP-) based deoxidation process for efficient recycling and reuse of metal powder in AM processes. The technique involves the highly reactive species generated in a H<sub>2</sub>-fed low-pressure radio frequency (RF) plasma discharge dynamically interacting with oxidized powder in a quartz tube reactor, thereby reducing oxide content without adversely affecting particle size or morphology. In this study using a bronze copper–tin alloy (CuSn10) powder, a >60% reduction in oxide content was achieved through the HP treatment of oxidized CuSn10 powder samples at the 10 g/batch scale as measured via inert gas fusion (IGF), which is a significant improvement and well below the measured oxygen content of the as-received virgin CuSn10 powder. HP-treated powder was further characterized to determine treatment effect on powder morphology, bulk particle structure, and surface chemical composition via laser diffraction and dynamic imaging analysis, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. Initial demonstration of process scale-up showed a >50% reduction in oxide content at an increased batch size of 100 g/batch.","PeriodicalId":39,"journal":{"name":"Industrial & Engineering Chemistry Research","volume":"32 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-03DOI: 10.1016/j.seppur.2024.130896
Dingliang Xu, Cong Yuan, Li Dai, Lin Zeng, Long Li, Xiangwei Guan, Wenjie Lv, Chengcheng Tian, Hualin Wang
Fine particles being captured or escaping from particle beds (microchannel separator) is a widespread phenomenon, with the size and distribution of pores (microchannel) significantly affecting these phenomena. However, due to the complexity of the pore structure, accurately measuring and validating it poses challenges. This paper introduces a new method to calculate the critical pore diameter of homogeneous microchannel separators (three types of homogeneous separation media with particle sizes of 0.8 mm, 1.0 mm and 1.2 mm). Initially, particle bed units with a thickness twice the diameter of the separation media were captured from multiple orthogonal projection directions to obtain high-resolution images of the pore structure. Then, the Feret diameter distribution of the pores were analyzed to quantify pore size and distribution. Next, unresolved CFD-DEM method was used to simulate the capture of fine particles to optimize and supplement the results. The results show that the average Feret diameter of the pores differs by only 0.85 μm, 1.70 μm, and 2.46 μm from the simulation results, and it is noted that the critical pore diameter is approximately 0.153 times that of the separation media diameter, the numerical difference from the critical dimension ratio is only 0.0017. Additionally, when the diameter of the fine particles is 0.155 to 0.165 times the diameter of the separation media, the homogeneous microchannel separator exhibits the highest efficiency during the deep bed filtration process. The study also examines the separation of homogeneous fine particles at varying inlet liquid flow rates, which can offer theoretical guidance for analyzing the porosity of microchannel separators and the efficient removal of solid pollutants, thus contributing novel ideas to deep bed filtration research.
{"title":"A method for measuring the critical pore diameter of a homogeneous microchannel separator based on image analysis and a simulation comparison of CFD-DEM","authors":"Dingliang Xu, Cong Yuan, Li Dai, Lin Zeng, Long Li, Xiangwei Guan, Wenjie Lv, Chengcheng Tian, Hualin Wang","doi":"10.1016/j.seppur.2024.130896","DOIUrl":"https://doi.org/10.1016/j.seppur.2024.130896","url":null,"abstract":"Fine particles being captured or escaping from particle beds (microchannel separator) is a widespread phenomenon, with the size and distribution of pores (microchannel) significantly affecting these phenomena. However, due to the complexity of the pore structure, accurately measuring and validating it poses challenges. This paper introduces a new method to calculate the critical pore diameter of homogeneous microchannel separators (three types of homogeneous separation media with particle sizes of 0.8 mm, 1.0 mm and 1.2 mm). Initially, particle bed units with a thickness twice the diameter of the separation media were captured from multiple orthogonal projection directions to obtain high-resolution images of the pore structure. Then, the Feret diameter distribution of the pores were analyzed to quantify pore size and distribution. Next, unresolved CFD-DEM method was used to simulate the capture of fine particles to optimize and supplement the results. The results show that the average Feret diameter of the pores differs by only 0.85 μm, 1.70 μm, and 2.46 μm from the simulation results, and it is noted that the critical pore diameter is approximately 0.153 times that of the separation media diameter, the numerical difference from the critical dimension ratio is only 0.0017. Additionally, when the diameter of the fine particles is 0.155 to 0.165 times the diameter of the separation media, the homogeneous microchannel separator exhibits the highest efficiency during the deep bed filtration process. The study also examines the separation of homogeneous fine particles at varying inlet liquid flow rates, which can offer theoretical guidance for analyzing the porosity of microchannel separators and the efficient removal of solid pollutants, thus contributing novel ideas to deep bed filtration research.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":"77 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, the power conversion efficiency (PCE) of a CdSe/CdTe/ZnTe quantum dot solar cell (QDSC) is investigated considering the influence of internal parameters such as CdSe core radius and CdTe and ZnTe shell thickness along with external parameters such as temperature and hydrostatic pressure. A comparative analysis is performed using both the original detailed balance model (ODBM) and the modified detailed balance model (MDBM). The main focus of the research is to investigate the effects of excitonic and biexcitonic effective gap energies, as well as the biexciton bound state, on the PCE in the presence of multiple exciton generation (MEG). Calculations using both ODBM and MDBM indicate that the distinct excitonic and biexcitonic effective bandgap energies, resulting from strong confinement effects in quantum dot (QD) structures, significantly affect the PCE in the presence of MEG. In addition, MDBM calculations considering the biexciton bound state show that this bound state critically affects the PCE. The discrepancy between the theoretically predicted maximum PCE and the considerably lower PCE observed in practical applications of QDSCs is also examined, along with the potential reasons for this phenomenon.
{"title":"Comparative Analysis of Excitonic and Biexcitonic Effects on the Power Conversion Efficiency of a CdSe/CdTe/ZnTe Quantum Dot Solar Cell","authors":"Murat Unluler, Fatih Koc","doi":"10.1002/adts.202400956","DOIUrl":"https://doi.org/10.1002/adts.202400956","url":null,"abstract":"In this study, the power conversion efficiency (PCE) of a CdSe/CdTe/ZnTe quantum dot solar cell (QDSC) is investigated considering the influence of internal parameters such as CdSe core radius and CdTe and ZnTe shell thickness along with external parameters such as temperature and hydrostatic pressure. A comparative analysis is performed using both the original detailed balance model (ODBM) and the modified detailed balance model (MDBM). The main focus of the research is to investigate the effects of excitonic and biexcitonic effective gap energies, as well as the biexciton bound state, on the PCE in the presence of multiple exciton generation (MEG). Calculations using both ODBM and MDBM indicate that the distinct excitonic and biexcitonic effective bandgap energies, resulting from strong confinement effects in quantum dot (QD) structures, significantly affect the PCE in the presence of MEG. In addition, MDBM calculations considering the biexciton bound state show that this bound state critically affects the PCE. The discrepancy between the theoretically predicted maximum PCE and the considerably lower PCE observed in practical applications of QDSCs is also examined, along with the potential reasons for this phenomenon.","PeriodicalId":7219,"journal":{"name":"Advanced Theory and Simulations","volume":"12 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-03DOI: 10.1016/j.copbio.2024.103230
Min Zheng , James Lloyd , Peter Wardrop , Haoran Duan , Tao Liu , Liu Ye , Bing-Jie Ni
Amid growing concerns over climate change, the need to reduce nitrous oxide (N2O) emissions from sewage treatment is more urgent than ever. Sewage treatment plants are significant sources of N2O due to its production as an intermediate in nitrification and its release into the air during aeration. Effective management of the nitrification process is therefore vital for controlling or eliminating these emissions. Despite substantial efforts to quantify and understand N2O emissions from sewage treatment, success in reducing them has been limited. This review discusses and proposes promising solutions for reducing N2O emissions in sewage treatment, evaluates the potential of various strategies, and identifies ways to accelerate their development and implementation.
{"title":"Path to zero emission of nitrous oxide in sewage treatment: is nitrification controllable or avoidable?","authors":"Min Zheng , James Lloyd , Peter Wardrop , Haoran Duan , Tao Liu , Liu Ye , Bing-Jie Ni","doi":"10.1016/j.copbio.2024.103230","DOIUrl":"10.1016/j.copbio.2024.103230","url":null,"abstract":"<div><div>Amid growing concerns over climate change, the need to reduce nitrous oxide (N<sub>2</sub>O) emissions from sewage treatment is more urgent than ever. Sewage treatment plants are significant sources of N<sub>2</sub>O due to its production as an intermediate in nitrification and its release into the air during aeration. Effective management of the nitrification process is therefore vital for controlling or eliminating these emissions. Despite substantial efforts to quantify and understand N<sub>2</sub>O emissions from sewage treatment, success in reducing them has been limited. This review discusses and proposes promising solutions for reducing N<sub>2</sub>O emissions in sewage treatment, evaluates the potential of various strategies, and identifies ways to accelerate their development and implementation.</div></div>","PeriodicalId":10833,"journal":{"name":"Current opinion in biotechnology","volume":"91 ","pages":"Article 103230"},"PeriodicalIF":7.1,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-03DOI: 10.1016/j.apenergy.2024.124829
Wanwan Zhang, Jørn Vatn, Adil Rasheed
Offshore wind turbines face substantial challenges in operation and maintenance due to the harsh marine environment and remote locations. Predictive maintenance, encompassing fault diagnostics and failure prognostics, is a promising maintenance strategy to address these challenges. To contribute to this strategy, an integrated data-driven model is developed for probabilistic failure prognostics at the component level. The remaining useful life of a gearbox pump in an offshore wind turbine is predicted accurately based on supervisory control and data acquisition data. In this approach, light gradient boosting machines are tuned to model normal temperatures. The gated recurrent unit outperforms other neural networks and is selected to process temperature residuals with a Bayesian neural network. Results show that the prediction at the 50% percentile precedes the true failure time by 3.83 h. Moreover, there is 97.5% confidence that the true failure time falls within around 5.3 h of the predicted time. Furthermore, the earliest alarm is issued at the 2.5% percentile, precisely 9.17 h prior to the true failure time. This study demonstrates the effectiveness of supervised learning and normal behavior modeling for probabilistic failure prognostics of offshore wind turbine components.
{"title":"Gearbox pump failure prognostics in offshore wind turbine by an integrated data-driven model","authors":"Wanwan Zhang, Jørn Vatn, Adil Rasheed","doi":"10.1016/j.apenergy.2024.124829","DOIUrl":"10.1016/j.apenergy.2024.124829","url":null,"abstract":"<div><div>Offshore wind turbines face substantial challenges in operation and maintenance due to the harsh marine environment and remote locations. Predictive maintenance, encompassing fault diagnostics and failure prognostics, is a promising maintenance strategy to address these challenges. To contribute to this strategy, an integrated data-driven model is developed for probabilistic failure prognostics at the component level. The remaining useful life of a gearbox pump in an offshore wind turbine is predicted accurately based on supervisory control and data acquisition data. In this approach, light gradient boosting machines are tuned to model normal temperatures. The gated recurrent unit outperforms other neural networks and is selected to process temperature residuals with a Bayesian neural network. Results show that the prediction at the 50% percentile precedes the true failure time by 3.83 h. Moreover, there is 97.5% confidence that the true failure time falls within around <span><math><mo>±</mo></math></span> 5.3 h of the predicted time. Furthermore, the earliest alarm is issued at the 2.5% percentile, precisely 9.17 h prior to the true failure time. This study demonstrates the effectiveness of supervised learning and normal behavior modeling for probabilistic failure prognostics of offshore wind turbine components.</div></div>","PeriodicalId":246,"journal":{"name":"Applied Energy","volume":"380 ","pages":"Article 124829"},"PeriodicalIF":10.1,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142759528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stress is a common everyday emotional state in modern society contributing to both physical and mental illnesses. Thus, detecting and managing the degree of stress is crucial to improve well-being. Wearable devices equipped with biosensors, such as PhotoPlethysmoGraphy (PPG), can measure reliably a person’s affective state. However, PPG-based approaches suffer from the presence of Motion Artifacts (MA) affecting their overall performance. Classical machine learning and deep learning approaches have been proposed over the years for PPG-based stress detection, exploiting signal processing techniques to remove the recorded noise, but lack explainability or their performance fails to generalize across subjects. In the current work, we present a novel architecture, TranSenseFuser comprised of temporal convolutions followed by feature-level or sequence-level multi-head attention to improve sensor fusion’s effectiveness and exploit the provided attention maps as a form of explainability. The developed models are evaluated on highly benchmarked public dataset, namely WESAD, achieving state-of-the-art results (up to 98.46% accuracy and 97.03% F1-score) using different window sizes and cross-validation set-ups. Moreover, we demonstrate the explainability of the model towards filtering out the motion artifacts by visualizing the obtained attention maps and quantify the performance of this artifact segmentation feature in a zeros-shot manner.
{"title":"TranSenseFusers: A temporal CNN-Transformer neural network family for explainable PPG-based stress detection","authors":"Panagiotis Kasnesis , Christos Chatzigeorgiou , Michalis Feidakis , Álvaro Gutiérrez , Charalampos Z. Patrikakis","doi":"10.1016/j.bspc.2024.107248","DOIUrl":"10.1016/j.bspc.2024.107248","url":null,"abstract":"<div><div>Stress is a common everyday emotional state in modern society contributing to both physical and mental illnesses. Thus, detecting and managing the degree of stress is crucial to improve well-being. Wearable devices equipped with biosensors, such as PhotoPlethysmoGraphy (PPG), can measure reliably a person’s affective state. However, PPG-based approaches suffer from the presence of Motion Artifacts (MA) affecting their overall performance. Classical machine learning and deep learning approaches have been proposed over the years for PPG-based stress detection, exploiting signal processing techniques to remove the recorded noise, but lack explainability or their performance fails to generalize across subjects. In the current work, we present a novel architecture, <em>TranSenseFuser</em> comprised of temporal convolutions followed by feature-level or sequence-level multi-head attention to improve sensor fusion’s effectiveness and exploit the provided attention maps as a form of explainability. The developed models are evaluated on highly benchmarked public dataset, namely WESAD, achieving state-of-the-art results (up to 98.46% accuracy and 97.03% F1-score) using different window sizes and cross-validation set-ups. Moreover, we demonstrate the explainability of the model towards filtering out the motion artifacts by visualizing the obtained attention maps and quantify the performance of this artifact segmentation feature in a zeros-shot manner.</div></div>","PeriodicalId":55362,"journal":{"name":"Biomedical Signal Processing and Control","volume":"102 ","pages":"Article 107248"},"PeriodicalIF":4.9,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142759757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-03DOI: 10.1007/s11116-024-10567-5
Caroline Koszowski, Stefan Hubrich, Rico Wittwer, Regine Gerike
Trip-level household travel surveys (HTS) are an efficient and widely used instrument in transport planning and research and are expected to remain in this role for at least the near future. Mode information is typically assigned to trips in these surveys based on a hierarchy of transport modes that hides important information on the individual stages which is particularly relevant for walking. This study develops a methodology for estimating detailed stage-level information for trip-level HTS that contain some information on stages, this is the sequence of used transport modes and the number of transfers in Public Transport (PT) trips. The methodology is developed based on detailed stage-level data from a sub-sample in the German National HTS MiD 2017 and directly applied to the German city-based HTS SrV 2018 which is a trip-level survey but contains stage-level information on modes and PT transfers. Linear Regression Models for estimating walking stage duration in PT and car trips are combined with simple heuristic estimations for the less frequent types of intermodal trips. Trip purpose, accompaniment and total trip duration are important predictors for walking stage duration. Trip-level and stage-level modal-split figures for the number, duration, and distance of trips and stages in SrV 2018 are computed with the developed methodology. About half of all stages and 30% of trips are done by walking. Walking stage duration is with around 38% considerable, this share drops to around 12% for walking stage distance.
{"title":"From trips to stages: a methodology for Generating Stage Information in trip-level Household travel surveys","authors":"Caroline Koszowski, Stefan Hubrich, Rico Wittwer, Regine Gerike","doi":"10.1007/s11116-024-10567-5","DOIUrl":"https://doi.org/10.1007/s11116-024-10567-5","url":null,"abstract":"<p>Trip-level household travel surveys (HTS) are an efficient and widely used instrument in transport planning and research and are expected to remain in this role for at least the near future. Mode information is typically assigned to trips in these surveys based on a hierarchy of transport modes that hides important information on the individual stages which is particularly relevant for walking. This study develops a methodology for estimating detailed stage-level information for trip-level HTS that contain some information on stages, this is the sequence of used transport modes and the number of transfers in Public Transport (PT) trips. The methodology is developed based on detailed stage-level data from a sub-sample in the German National HTS MiD 2017 and directly applied to the German city-based HTS SrV 2018 which is a trip-level survey but contains stage-level information on modes and PT transfers. Linear Regression Models for estimating walking stage duration in PT and car trips are combined with simple heuristic estimations for the less frequent types of intermodal trips. Trip purpose, accompaniment and total trip duration are important predictors for walking stage duration. Trip-level and stage-level modal-split figures for the number, duration, and distance of trips and stages in SrV 2018 are computed with the developed methodology. About half of all stages and 30% of trips are done by walking. Walking stage duration is with around 38% considerable, this share drops to around 12% for walking stage distance.</p>","PeriodicalId":49419,"journal":{"name":"Transportation","volume":"80 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-03DOI: 10.1021/acs.iecr.4c02921
Sophie A. Brauer, Isaac A. Mastalski, Madeline A. Murphy, Benjamin R. Hoekstra, Lyle E. Monson, Paul J. Dauenhauer, Christopher P. Nicholas
Kinetic description of the hydrolysis of alkyl lactates has been limited to acid-catalyzed conditions despite the spontaneous hydrolysis of methyl lactate and ethyl lactate in aqueous solution. As the reaction progresses, generated lactic acid further catalyzes ester hydrolysis, while the rate of the reverse esterification reaction also increases with the accumulation of acid product. The reaction sequence of lactate hydrolysis is described in three kinetic stages: initiation/neutral hydrolysis, autocatalytic hydrolysis, and equilibrium. The evolution of lactate hydrolysis was measured for varying temperatures (1.5 to 40 °C) and initial concentrations of methyl or ethyl lactate (1 to 40 mol %) to quantify the kinetic transitions between reaction stages. Lower temperatures resulted in a distinct induction period where negligible hydrolysis was observed. The effect of initial concentration on the length of the induction period was nonmonotonic and was divided into dilute (below about 6 mol % lactate) and concentrated (above about 6 mol %) regimes. Solutions of either lower or higher lactate concentration corresponded to longer induction periods and slower reactions. A dual kinetic regime best describes the observed hydrolysis behavior. For hydrolysis of alkyl lactates below 10 mol %, a rate law derived from the conventional ester hydrolysis mechanism effectively modeled behavior, while at higher lactate concentrations, an additional water molecule must be included in the rate-determining step to appropriately capture the hydrolysis behavior.
{"title":"Dual-Regime Reaction Kinetics of the Autocatalytic Hydrolyses of Aqueous Alkyl Lactates","authors":"Sophie A. Brauer, Isaac A. Mastalski, Madeline A. Murphy, Benjamin R. Hoekstra, Lyle E. Monson, Paul J. Dauenhauer, Christopher P. Nicholas","doi":"10.1021/acs.iecr.4c02921","DOIUrl":"https://doi.org/10.1021/acs.iecr.4c02921","url":null,"abstract":"Kinetic description of the hydrolysis of alkyl lactates has been limited to acid-catalyzed conditions despite the spontaneous hydrolysis of methyl lactate and ethyl lactate in aqueous solution. As the reaction progresses, generated lactic acid further catalyzes ester hydrolysis, while the rate of the reverse esterification reaction also increases with the accumulation of acid product. The reaction sequence of lactate hydrolysis is described in three kinetic stages: initiation/neutral hydrolysis, autocatalytic hydrolysis, and equilibrium. The evolution of lactate hydrolysis was measured for varying temperatures (1.5 to 40 °C) and initial concentrations of methyl or ethyl lactate (1 to 40 mol %) to quantify the kinetic transitions between reaction stages. Lower temperatures resulted in a distinct induction period where negligible hydrolysis was observed. The effect of initial concentration on the length of the induction period was nonmonotonic and was divided into dilute (below about 6 mol % lactate) and concentrated (above about 6 mol %) regimes. Solutions of either lower or higher lactate concentration corresponded to longer induction periods and slower reactions. A dual kinetic regime best describes the observed hydrolysis behavior. For hydrolysis of alkyl lactates below 10 mol %, a rate law derived from the conventional ester hydrolysis mechanism effectively modeled behavior, while at higher lactate concentrations, an additional water molecule must be included in the rate-determining step to appropriately capture the hydrolysis behavior.","PeriodicalId":39,"journal":{"name":"Industrial & Engineering Chemistry Research","volume":"26 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-03DOI: 10.1016/j.cej.2024.158223
Yongchuan Liu, Jie Shen, Guolin Hu, Guihuang Fang, Yuanqiang Chen, Xiangxin Zhang, Zhanlin Yang, Baisheng Sa, Yining Zhang
In subzero environments, sluggish electrochemical kinetics and unstable electrode/electrolyte interphases hinder progress in lithium metal batteries (LMBs), emphasizing the need for advanced electrolytes to ensure stability in harsh environments. Herein, we proposed a balanced “cocktail optimized” electrolyte by manipulating solvated and anionic species. The dual salt/dual solvent electrolyte simultaneously achieves low bulk impedance and low interfacial impedance, while also demonstrating improved Li reversibility and oxidation stability. The tailored solvation structure encourages the breakdown of anions, leading to the formation of inorganic-rich interphases at both the cathode and Li-anode, which enables a uniform plating-stripping of Li while maintaining exceptional voltage resilience on the cathode. Moreover, NO3– ions preferentially adsorb onto the cathode surface within the inner Helmholtz plane, shielding the easily-oxidized non-solvating solvent molecules, a phenomenon referred to as the “shielding effect”, thus inhibiting side oxidation reactions. Consequently, the anion-derived interface chemistry contributes to the dendrite-free Li deposition with a high CE of 99.45%, a stable cycling of Li||NCM523 battery with 85% capacity retention after 150 cycles, and a superior low-temperature discharge performance at −30 ℃ with a capacity retention of 68.2%. This work sheds light on an encouraging electrolyte strategy for stable LMBs in a wide-temperature range.
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