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三氧化钨催化糖分子选择裂解新机理及其对生物质利用的重要意义

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Chinese Journal of Catalysis 2023年第3期46卷 1-3页

作者： johannes A.Lercher 德国慕尼黑工业大学德国加兴美国西北太平洋国家实验室美国里奇兰

糖类化合物催化转化合成燃料和化学品为现有化石路线提供了可行的替代方案.碳化钨、氧化钨和钨酸等钨基催化剂具有催化糖分子碳-碳键选择性断裂生成乙二醇、丙二醇等C_(2,3)产物的独特性能.然而,对该催化反应的机理还一直缺乏明确的认识... 详细信息

糖类化合物催化转化合成燃料和化学品为现有化石路线提供了可行的替代方案.碳化钨、氧化钨和钨酸等钨基催化剂具有催化糖分子碳-碳键选择性断裂生成乙二醇、丙二醇等C_(2,3)产物的独特性能.然而,对该催化反应的机理还一直缺乏明确的认识.最近北京大学刘海超团队报道,糖分子的羰基、α-和β-羟基与三氧化钨(WO_(3))表面的两个邻近钨原子(W-O-W结构)配位,形成一种双钨三齿螯合物;该螯合物作为反应的关键中间体,引发羰基β-位的碳-碳键断裂,从而实现糖分子的选择裂解.该新反应机理不仅为糖化学提供了新的认识,而且为糖基生物质提供了一个经乙醇醛、甘油醛等C_(2,3)中间体转化为化学品的有效策略.固体核磁表征结果表明,吸附到WO_(3)表面的^(13)Cc标记葡萄糖的C1、C2和C3三个碳原子与表面钨原子形成了C-O-W键,从而在去屏蔽作用下化学位移向低场移动,说明糖分子需要羰基以及α-和β-羟基三个官能团共同参与才具有反应活性.催化反应结果表明,含有W-O-W结构的钨基化合物均表现出催化糖分子裂解生成C_(2,3)产物的活性,例如:仲钨酸铵、磷钨酸盐和钨青铜等均相、多相催化剂都能有效地将葡萄糖转化为乙二醇.通过理论计算分别模拟L-苏阿糖和2-脱氧-L-苏阿糖在WO_(3)(001)晶面上的反应过程,发现前者形成的L-苏阿糖-三氧化钨三齿螯合物,在后续碳-碳键选择性断裂生成一分子乙醇醛和一分子表面结合的乙烯二醇中间物种过程中,只有-0.01 eV的能量变化以及0.53 eV的能垒;而2-脱氧-L-苏阿糖则不同,由于缺乏α-羟基,后续碳-碳键断裂过程中需要吸收0.20 eV的能量和克服0.62 eV的能垒.计算结果进一步证明了糖-三氧化钨三齿螯合物中间体和糖分子α-羟基在反应中发挥了至关重要的作用.刘海超团队这项开拓性的工作揭示了三氧化钨催化糖分子碳-碳键选择性断裂的新机理,扩展了教科书中对经典逆羟醛缩合反应机理的描述.在该机理指导下,来源多样、纯度不同和结构各异的糖类化合物均能够在钨基催化剂作用下经乙醇醛和甘油醛等C_(2,3)中间体转化为化学品,从而为糖基生物质高效利用提供了具有实用意义的新策略.这正如现代石油化工所普遍采用的方法,首先将石油原料经过催化裂化或水汽裂解转化为乙烯、丙烯等C_(2,3)中间体,然后进一步转化为下游丰富的化学品.因此,该项研究工作对于纤维素、半纤维素等糖基生物质的高效转化利用具有重要意义.

关键词：生物质糖三氧化钨碳–碳键断裂非经典逆羟醛缩合反应机理

Decision support for the development,simulation and optimization of dynamic process models

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Frontiers of Chemical Science and Engineering 2022年第2期16卷 210-220页

作者： Norbert Asprion Roger Böttcher Jan Schwientek johannes Höller Patrick Schwartz Charlie Vanaret Michael Bortz BASF SE 67063 LudwigshafenGermany Fraunhofer ITWM 67663 KaiserslauternGermany

Simulation is besides experimentation the major method for designing,analyzing and optimizing chemical *** ability of simulations to reflect real process behavior strongly depends on model *** and adaption of process models are usually based on available plant *** such a model in various simulation and optimization studies can support the process designer in his *** steady state models there is also a growing demand for dynamic models either to adapt faster to changing conditions or to reflect batch *** this contribution challenges of extending an existing decision support framework for steady state models to dynamic models will be discussed and the resulting opportunities will be demonstrated for distillation and reactor examples.

关键词： decision support multicriteria optimization model validation dynamic model sensitivity analysis

Single-model uncertainty quantification in neural network potentials does not consistently outperform model ensembles

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npj Computational Materials 2023年第1期9卷 49-59页

作者： Aik Rui Tan Shingo Urata Samuel Goldman johannes C.B.Dietschreit Rafael Gómez-Bombarelli Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMAUSA Innovative Technology Laboratories AGC IncTokyoJapan Computational and Systems Biology Massachusetts Institute of TechnologyCambridgeMAUSA

Neural networks(NNs)often assign high confidence to their predictions,even for points far out of distribution,making uncertainty quantification(UQ)a *** they are employed to model interatomic potentials in materials systems,this problem leads to unphysical structures that disrupt simulations,or to biased statistics and dynamics that do not reflect the true *** UQ techniques can find new informative data and drive active learning loops for robust ***,a variety of UQ techniques,including newly developed ones,exist for atomistic simulations and there are no clear guidelines for which are most effective or suitable for a given *** this work,we examine multiple UQ schemes for improving the robustness of NN interatomic potentials(NNIPs)through active *** particular,we compare incumbent ensemble-based methods against strategies that use single,deterministic NNs:mean-variance estimation(MVE),deep evidential regression,and Gaussian mixture models(GMM).We explore three datasets ranging from in-domain interpolative learning to more extrapolative out-of-domain generalization challenges:rMD17,ammonia inversion,and bulk silica *** is measured across multiple metrics relating model error to *** experiments show that none of the methods consistently outperformed each other across the various *** remained better at generalization and for NNIP robustness;MVE only proved effective for in-domain interpolation,while GMM was better out-of-domain;and evidential regression,despite its promise,was not the preferable alternative in any of the *** broadly,cost-effective,single deterministic models cannot yet consistently match or outperform ensembling for uncertainty quantification in NNIPs.

关键词： ensemble evident neural

Explaining farmers'reluctance to adopt green manure cover crops planting for sustainable agriculture in Northwest China

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Journal of Integrative Agriculture 2022年第11期21卷 3382-3394页

作者： Sheng-Han-Erin CHANG YI Xiao-yan johannes SAUER YIN Chang-bin LI Fu-duo Agricultural Production and Resource Economics Technical University of MunichFreising 85354Germany Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Green manure cover crops(GMCCs)planting has a potential for mitigating greenhouse gas emissions(GHG)in agroecosystems and provides important ecosystem services,thereby achieving the Sustainable Development Goals(SDGs)stipulated by the United ***,the advantages of cultivating GMCCs on arable land are not widely *** example,in the whole of China,the GMCCs planting area is less than 3.5%of total arable *** aim of this study is to explore reasons for the low adoption rate of GMCCs *** best–worst scaling(BWS)approach,farmers ranked their preferred conservation practices including three types of GMCC cropping *** Gansu Province in Northwest China as a case study,a survey with 276 farmers was *** findings indicated that three factors are related to the low adoption rate of GMCCs:1)farmers preferred improving farmland irrigation facilities and substituting chemical fertilizers with organic rather than planting GMCCs;2)lack of awareness and understanding of government policy on GMCCs and limited access to training courses;3)financial support and subsidies from the government are *** study provides insights and strategic implications for policymakers on how to further promote GMCCs in the future.

关键词： best–worst scaling farmers'preferences green manure cover crops sustainable agriculture Northwest China

Pneumothorax in a Thiel cadaver model of cardiopulmonary resuscitation

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World Journal of Emergency Medicine 2023年第2期14卷 143-147页

作者： Daniel Auinger Simon Orlob johannes Wittig Gabriel Honnef Stefan Heschl Georg Feigl Gerhard Prause Division of Anaesthesiology and Intensive Care Medicine 1 Department of Anaesthesiology and Intensive Care MedicineMedical University of GrazGraz 8036Austria Division of Anaesthesiology and Intensive Care Medicine 2 Department of Anaesthesiology and Intensive Care MedicineMedical University of GrazGraz 8036Austria Medical University of Graz Graz 8036Austria Research Center for Emergency Medicine Aarhus University HospitalAarhus 8200Denmark Department of Medicine Randers Regional HospitalRanders 8930Denmark Chair of Macroscopic and Clinical Anatomy Gottfried Schatz Research CenterMedical University of GrazGraz 8036Austria Institute of Morphology and Clinical Anatomy Faculty of Health/School of MedicineWitten/Herdecke UniversityWitten 58448Germany

INTRODUCTION There has been some previous research in the field of cardiopulmonary resuscitation (CPR) using cadaver models.[1]The Thiel method was developed by Professor Walter Thiel (Graz, Austria) and described in 1992 and 2002. It consists of both an intravascular injection of the embalming solution and submersion of the bodies in a tank with the same solution for a determined period.[2,3]

关键词： Walter cardiopulmonary bal

Lymphangiogenesis: A new player in the heart’s adaptive response to exercise

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Journal of Sport and Health Science 2022年第4期11卷 421-423页

作者： Sanela Dozic johannes V.Janssens Kate L.Weeks Central Clinical School Monash UniversityMelbourneVIC 3004Australia Department of Anatomy&Physiology The University of MelbourneParkvilleVIC 3010Australia Baker Department of Cardiometabolic Health The University of MelbourneParkvilleVIC 3010Australia Department of Diabetes Central Clinical SchoolMonash UniversityMelbourneVIC 3004Australia

The heart’s lymphatic network is essential for maintaining fluid and immune cell *** vessels return interstitial fluid to the bloodstream,transport macromolecules such as proteins and lipids,and clear the heart of inflammatory cells.1 Several studies have demonstrated the importance of cardiac lymphatics and lymphangiogenesis(the formation of new lymphatic vessels from pre-existing vessels)in settings of cardiac pathology.2-6 Blocking endogenous lymphangiogenesis during myocardial infarction exacerbates myocardial edema and cardiac inflammation and fibrosis,while enhancing lymphangiogenesis attenuates ischemia-induced heart failure and pressure overload-induced cardiac dysfunction.3-5 Collectively,these studies identify stimulation of lymphangiogenesis as a potential therapeutic strategy for the treatment of cardiovascular diseases and heart failure.

关键词： cardiac stimulation endogenous

Large scale mapping of forest attributes using heterogeneous sets of airborne laser scanning and National Forest Inventory data

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Forest Ecosystems 2021年第4期8卷 872-886页

作者： Marius Hauglin johannes Rahlf johannes Schumacher Rasmus Astrup johannes Breidenbach Norwegian Institute of Bioeconomy Research AsNorway

Background:The Norwegian forest resource map(SR16)maps forest attributes by combining national forest inventory(NFI),airborne laser scanning(ALS)and other remotely sensed *** the ALS data were acquired over a time interval of 10 years using various sensors and settings,the NFI data are continuously *** of this study were to analyze the effects of stratification on models linking remotely sensed and field data,and assess the accuracy overall and at the ALS project *** and methods:The model dataset consisted of 9203 NFI field plots and data from 367 ALS projects,covering 17 Mha and 2/3 of the productive forest in ***-effects regression models were used to account for differences among ALS *** types of stratification were used to fit models:1)stratification by the three main tree species groups spruce,pine and deciduous resulted in species-specific models that can utilize a satellite-based species map for improving predictions,and 2)stratification by species and maturity class resulted in stratum-specific models that can be used in forest management inventories where each stand regularly is visually stratified *** models were compared to general models that were fit without stratifying the ***:The species-specific models had relative root-mean-squared errors(RMSEs)of 35%,34%,31%,and 12% for volume,aboveground biomass,basal area,and Lorey’s height,*** RMSEs were 2-7 percentage points(pp)smaller than those of general *** validating using predicted species,RMSEs were 0-4 *** than those of general *** stratified by main species and maturity class further improved RMSEs compared to species-specific models by up to 1.8 *** mixed-effects models over ordinary least squares models resulted in a decrease of RMSE for timber volume of 1.0-3.9 pp.,depending on the main tree *** for timber volume ranged between 19%-59% among individual ALS ***

关键词： NFI Lidar Mixed-effects models Wall-to-wall mapping

Ultrahigh frame rate digital light projector using chip-scale LED-on-CMOS technology

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Photonics Research 2022年第10期10卷 2434-2446页

作者： NAVID BANI HASSAN FAHIMEH DEHKHODA ENYUAN XIE johannes HERRNSDORF MICHAEL J.STRAIN ROBERT HENDERSON MARTIN D.DAWSON Institute of Photonics Department of PhysicsUniversity of StrathclydeTechnology and Innovation CentreGlasgow G11RDUK School of Engineering Institute for Integrated Micro and Nano SystemsUniversity of EdinburghEdinburgh EH93JLUK

Digital light projector systems are crucial components in applications,including computational imaging,fluorescence microscopy,and highly parallel data *** technology based on digital micromirror displays are limited to absolute frame rates in the few tens of kiloframes per second and require the use of external light sources and coupling ***,to realize gray-scale pixel values using duty cycle control,frame rates are reduced proportionally to the number of gray levels *** we present a self-emissive chip-scale projector system based on micro-LED pixels directly bonded to a smart pixel CMOS drive *** 128×128 pixel array can project binary patterns at up to 0.5 Mfps and toggle between two stored frames at megahertz *** projector has a 5-bit gray-scale resolution that can be updated at up to 83 kfps,and can be held in memory as a constant bias for the binary pattern ***,the projector can be operated in a pulsed mode,with individual pixels emitting pulses down to a few nanoseconds in ***,this mode can be used in conjunction with the high-speed spatial pattern *** a demonstration of the data throughput achievable with this system,we present an optical camera communications application,exhibiting data rates of>5 Gb/s.

关键词： frame frames light

Virtual reality for immersive multi-user firefighter-training scenarios

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Virtual Reality & Intelligent Hardware 2022年第5期4卷 406-417页

作者： Philipp BRAUN Michaela GRAFELMANN Felix GILL Hauke STOLZ johannes HINCKELDEYN Ann-Kathrin LANGE Hamburg University of Technology Hamburg 21073Germany

Background Virtual reality(VR)applications can be used to provide comprehensive training scenarios that are difficult or impossible to represent in physical *** includes team training for emergency services such as *** a high level of immersion is essential for achieving effective virtual *** this respect,motion-capture systems offer the possibility of creating highly immersive multi-user training experiences,including full-body *** This study presents a preliminary prototype that helps extin-guish a virtual fire on a container ship as a VR training *** prototype provides a full-body and multi-user VR experience based on the synthesis of position data provided by the motion-capture system and orientation data from the VR ***,the prototype facilitates an initial evaluation of the *** The results confirm the value of using VR for training procedures that are difficult to implement in the real ***,the results show that motion-capture-based VR technologies are particularly useful for firefighting training,in which participants can collaborate in difficult-to-access ***,this study also indicates that increasing the immersion in such training remains a *** This study presents a prototypical VR application that enables the multi-user training of maritime *** research should evaluate the initial results,provide more extensive training scenarios,and measure the training progress.

关键词： Virtual reality Multi-user Motion capture Training Firefighting