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Three-Dimensional Convection in an Inclined Porous Layer Subjected to a Vertical Temperature Gradient

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Fluid Dynamics & Materials Processing 2024年第9期20卷 1957-1970页

作者： Ivan Shubenkov Tatyana Lyubimova Evgeny Sadilov computational Fluid Dynamics {1. Institute of Continuous Media Mechanics UB RASPerm614068Russia Theoretical Physics Department Perm State UniversityPerm614990Russia

In this paper,we study the onset and development of three-dimensional convection in a tilted porous layer saturated with a *** layer is subjected to a gravitational field and a strictly vertical temperature ***,problems of thermal convection in tilted porous media saturated with a liquid are studied by assuming constant different temperatures at the boundaries of the layer,which prevent these systems from supporting conductive(non-convective)*** boundary conditions considered in the present work allow a conductive state and are representative of typical geological *** an earlier work,we carried out a linear stability analysis of the conductive *** was shown that at any layer tilt angles,the most dangerous type of disturbances are longitudinal ***,a non-zero velocity component exists in *** the present work,threedimensional non-linear convection regimes are *** original three-dimensional problem is reduced to two-dimensional one with an analytical expression for the velocity z-component v_(z)=v_(z)(x,y).It is shown that the critical Rayleigh number values obtained through numerical solutions of the obtained 2D problem by a finite difference method for different layer inclination angles,are in a good agreement with those predicted by the linear *** number of convective rolls realized in nonlinear calculations also fits the linear theory predictions for a given cavity *** carried out at low supercriticalities show that a direct bifurcation takes *** increasing supercriticality,no transitions to other convective regimes are *** situation studied in this problem can be observed in oil-bearing rock formations under the influence of a geothermal temperature gradient,where the ensuing fluid convection can affect the distribution of oil throughout the layer.

关键词： Thermal convection inclined layer porous media vertical temperature gradient

Dormancy heterogeneity among Arabidopsis thaliana seeds is linked to individual seed size

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Plant Communications 2024年第2期5卷 215-227页

作者： Michal Krzyszton Sebastian P.Sacharowski Veena Halale Manjunath Katarzyna Muter Grzegorz Bokota Ce Wang Dariusz Plewczynski Tereza Dobisova Szymon Swiezewski laboratory of Seeds Molecular Biology Institute of Biochemistry and BiophysicsPAS02-106 WarsawPoland laboratory of Functional and Structural Genomics Centre of New TechnologiesUniversity of WarsawWarsawPoland laboratory of Bioinformatics and {1. Genomics Faculty of Mathematics and Information ScienceWarsaw University of TechnologyWarsawPoland Labdeers Ltd. 680-01 BoskoviceCzech Republic

Production of morphologically and physiologically variable seeds is an important strategy that helps plants to survive in unpredictable natural ***,the model plant Arabidopsis thaliana and most agronomically essential crops produce visually homogenous *** automated phenotype analysis,we observed that small seeds in Arabidopsis tend to have higher primary and secondary dormancy levels than large *** analysis revealed distinct gene expression profiles between large and small *** seeds have higher expression of translation-related genes implicated in germination *** contrast,small seeds have elevated expression of many positive regulators of dormancy,including a key regulator of this process,the DOG1.*** in DOG1.expression are associated with differential production of its alternative cleavage and polyadenylation isoforms;in small seeds,the proximal poly(A)site is selected,resulting in a short mRNA ***,single-seed RNA sequencing analysis demonstrated that large seeds resemble DOG1.knockout mutant ***,on the single-seed level,expression of genes affected by seed size is correlated with expression of genes that position seeds on the path toward *** results demonstrate an unexpected link between seed size and dormancy phenotypes in a species that produces highly homogenous seed pools,suggesting that the correlation between seed morphology and physiology is more widespread than initially assumed.

关键词： seed size dormancy DOG1 Arabidopsis

Counterfactual analysis of the 2023 Omicron XBB wave in China

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Infectious Disease Modelling 2024年第1期9卷 195-203页

作者： Hengcong Liu Xiangyanyu Xu Xiaowei Deng Zexin Hu Ruijia Sun Junyi Zou Jiayi Dong Qianhui Wu Xinhua Chen Lan Yi Jun Cai Juanjuan Zhang Marco Ajelli Hongjie Yu School of Public Health Fudan UniversityKey Laboratory of Public Health SafetyMinistry of EducationShanghaiChina laboratory for {1. Epidemiology and Public Health Department of Epidemiology and BiostatisticsIndiana University School of Public HealthBloomingtonINUSA

Background:China has experienced a COVID-1. wave caused by Omicron XBB variant starting in April *** aim is to conduct a retrospective analysis exploring the dynamics of the outbreak under counterfactual scenarios that combine the use of vaccines,antiviral drugs,and nonpharmaceutical ***:We developed a mathematical model of XBB transmission in China,which has been calibrated using SARS-CoV-2 positive rates per *** age-specific infection-hospitalization risk,infection-ICU risk,and infection-fatality risk were used to estimate disease burdens,characterized as number of hospital admissions,ICU admissions,and ***:We estimated that in absence of behavioral change,the XBB outbreak in spring 2023 would have resulted in 0.86 billion infections(∼61.of the total population).Our counterfactual analysis shows that the synergetic effect of vaccination(70%vaccination coverage),antiviral treatment(20%receiving antiviral treatment),and moderate nonpharmaceutical interventions(20%isolation and L1.PHSMs)could reduce the number of deaths to levels close to seasonal influenza(1.1. vs.0.65 per 1.,000 individuals and 5.85 vs.3.85 per 1.,000 individuals aged 60+,respectively).The maximum peak prevalence of hospital and ICU admissions are estimated to be lower than the corresponding capacities(8.6 vs.1..4 per 1.,000 individuals and 1.2 vs.2.1.per 1.,000 individuals,respectively).Conclusion:Our findings suggest that the capacity of the Chinese healthcare system was adequate to face the Omicron XBB wave in spring 2023 but,at the same time,supports the importance of administering highly effective vaccine with long-lasting immune response,and the use of antiviral treatments.

关键词： wave analysis starting

Surface reconstruction and structural transformation of twodimensional Ni-Fe MOFs for oxygen evolution in seawater media

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Nano Research 2024年第4期17卷 2429-2437页

作者： Liyuan Xiao Xue Bai Jingyi Han Tianmi Tang Siyu Chen Hui Qi Changmin Hou Fuquan Bai Zhenlu Wang Jingqi Guan Institute of Physical Chemistry College of ChemistryJilin UniversityChangchun 130021China The Second Hospital of Jilin University Changchun 130021China State Key laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China laboratory of Theoretical and {1. Chemistry Institute of Theoretical ChemistryCollege of ChemistryChangchun 130023China

As a four-electron transfer reaction,oxygen evolution reaction(OER)is limited by large overpotential and slow ***,we in-situ synthesized two-dimensional(2D)Ni-Fe metal-organic framework nanosheets on nickel foam(NixFe-TPA/NF,TPA=terephthalic acid)for oxygen evolution in alkaline and alkaline seawater *** 1.M KOH,Ni3Fe-TPA/NF shows a low overpotential(η1.)of 1.9 mV at 1. mA·cm^(-2) and an ultra-low overpotential of only 260 mV at 500 mA·cm^(-2).In alkaline seawater,Ni3Fe-TPA/NF still provides impressive OER performance,with anη1. of 265 ***-situ Raman characterization results show that the phase transition occurs during the OER,and Ni3FeOOH with more oxygen vacancies is in-situ formed,reducing the OER energy *** functional theory(DFT)reveals that the synergy between Ni and Fe reduces the energy barrier and accelerates the rate-determining *** addition,the ultra-thin 2D sheet structure and the close combination of Ni3FeOOH and highly conductive NF support ensure the high catalytic OER ***,the surface reconstruction and structural modification strategy can be used to design and prepare high-performance OER electrocatalysts for energy-related applications.

关键词： density functional theory(DFT)calculation Ni3FeOOH oxygen evolution reaction seawater electrolysis surface reconstruction

Peroxidase-like active Cu-ZIF-8 with rich copper(I)-nitrogen sites for excellent antibacterial performances toward drug-resistant bacteria

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Nano Research 2024年第8期17卷 7427-7435页

作者： Xiaoze Wang Hui Wang Jingkun Zhang Ning Han Wenjun Ma Donghai Zhang Mingshui Yao Xianliang Wang Yunfa Chen State Key laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of the Chinese Academy of Sciences Beijing 100049China laboratory of Theoretical and {1. Nanoscience CAS Key Laboratory of Nanosystem and Hierarchial FabricationCAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China China CDC Key laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China

Bacterial pathogens pose a serious threat to human health,and there is an urgent need to develop highly effective antibacterial materials to eliminate the increasingly serious contamination of drug-resistant ***,a Cu-doped ZIF-8 particle with unsaturated copper exhibits high peroxidase-like activity.99.998%antibacterial efficiency against *** can be achieved for 30 min at a low concentration of 50μg·mL^(−1.,as well as complete sterilization against ***(up to 8 log).99.999%antibacterial efficiency against Methicillin-resistant Staphylococcus aureus can be achieved,performing orders of magnitude higher than *** mechanism shows that the unsaturated Cu-Nx sites are enzyme-like active centers,which could promote the consumption of bacteria reducing substances by H_(2)O_(2),and the generated*OH further aggravates bacterial oxidative stress and membrane *** importantly,the oxidation activity of adsorbed oxygen species on Cu-ZIF-8 is enhanced by charge transfer and structural changes between the ligand and copper center like natural ***-doped ZIF-8 with peroxidase-like activity shows great potential in antibacterial application and the revealed catalytic mechanism is helpful for understanding the high antibacterial activity of nanoparticles with Cu-Nx sites.

关键词： Cu-doped ZIF-8 peroxidase-like reactive oxygen species(ROS) catalytic mechanism antibacterial activity

Spectroscopy and molecule opacity investigation on excited states of SiS

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Chinese Physics B 2024年第5期33卷 381-387页

作者：李瑞吕浩男桑纪群刘晓华梁桂颖吴勇 College of Teacher Education Qiqihar UniversityQiqihar 161006China National Key laboratory of {1. Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Department of Physics College of ScienceQiqihar UniversityQiqihar 161006China School of Data Science and Artificial Intelligence Jilin Engineering Normal UniversityChangchun 130052China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100084China

The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many *** to complex interactions among its low-lying electronic states,precise information regarding the molecular structure of SiS is *** obtain accurate information about the structure of its excited states,the high-precision multireference configuration interaction(MRCI)method has been *** method is used to calculate the potential energy curves(PECs)of the 1.Λ–S states corresponding to the lowest dissociation limit of *** core–valence correlation effect,Davidson’s correction and the scalar relativistic effect are also included to guarantee the precision of the MRCI *** on the calculated PECs,the spectroscopic constants of quasi-bound and bound electronic states are calculated and they are in accordance with previous experimental *** transition dipole moments(TDMs)and dipole moments(DMs)are determined by the MRCI *** addition,the abrupt variations of the DMs for the 1.(5)Σ^(+)and 2^(5)Σ^(+)states at the avoided crossing point are attributed to the variation of the electronic *** opacity of SiS at a pressure of 1.0 atms is presented across a series of *** increasing temperature,the expanding population of excited states blurs the band boundaries.

关键词： SiS opacity excited state spectroscopic constant configuration interaction

Decomposition of pre-existing Au–P clusters induced in situ a-Fe grains uniformization in Fe–P-based nanocrystalline alloys

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Rare Metals 2024年第10期43卷 5242-5255页

作者： Min-Hao Han Cheng Sun Guo-Guo Xi Yang Meng Qiang Luo Xue-Qian Yu Wen-Feng Zhang Hao Liu Hong-Jie Xu Tao Zhang Key laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang University laboratory of Functional Fiber Materials Institute of Bast Fiber CropsChinese Academy of Agricultural Science School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast University Institute for Advanced Materials North China Electric Power University Center for Advanced Analysis and computational Science Zhengzhou University

In Fe-based amorphous-/nanocrystalline ribbons,the uniformization and refinement of a-Fe grains are key aspects for optimizing their soft magnetic and mechanical ***,the Fe–P–C–B nanocrystalline alloy system was selected for *** produced as-spun ribbons with pre-existing nanocrystals through melt-quenching and then obtained a well-distributed a-Fe nanocrystalline structure through annealing below the first crystallization onset temperature （633 K）resulting in excellent magnetic properties (saturation magnetization of 1.65 T and coercivity of 1.6 A·m-1.ultra-wide annealing temperature window （from 61. to 733 K）,and extremely high annealing stability （up to 480 min at 633 K）.Furthermore,we propose a new in situ two-step mechanism for the uniformization of a-Fe nanocrystals,which is separately induced by the decomposition of the Au–P clusters and the pre-existing a-Fe nanocrystals during *** work underscores the crucial significance of micro-alloying via metastable clusters primarily influenced by metal-phosphide interactions in the process of refining a-Fe ***,i introduces a new principle for optimizing the comprehensive properties of Fe-based amorphous/nanocrystalline alloys.

关键词： Fe-based nanocrystalline alloys In-situ nano-crystallization Micro-alloying Soft magnetic property

The microscopic formation mechanism of O+H_(2) products from photodissociation of H_(2)O

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Chinese Journal of Structural Chemistry 2024年第5期43卷 11-13页

作者： Yubang Li Xixi Hu Daiqian Xie Kuang Yaming Honors School Jiangsu Key Laboratory of Vehicle Emissions ControlNanjing UniversityNanjing210023China Institute of Theoretical and computational Chemistry Key Laboratory of Mesoscopic ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China

Photodissociation dynamics of water involving its B electronic states yielding OH(A^(2)Σ+/X^(2)Π)+H(^(2)S)products has been intensively investi-gated by both experimental and theoretical studies[1..Theoretically,the Dobbyn-Knowles potential energy surfaces(DK PESs)[2]based on limited complete active space self-consistent field(CASSCF)points were used in dynamic studies for water photodissociation and O+H_(2)reaction about 20 years ago,but the accuracy is not enough to meet current re-quirements.

关键词： mechanism enough yielding

Leveraging Uncertainty for Depth-Aware Hierarchical Text Classification

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Computers, Materials & Continua 2024年第9期80卷 4111-4127页

作者： Zixuan Wu Ye Wang Lifeng Shen Feng Hu Hong Yu Chongqing Key laboratory of {1. Intelligence Chongqing University of Posts and TelecommunicationsChongqing400000China Division of Emerging Interdisciplinary Areas Hong Kong University of Science and TechnologyHong Kong999077China

Hierarchical Text Classification(HTC)aims to match text to hierarchical *** methods overlook two critical issues:first,some texts cannot be fully matched to leaf node labels and need to be classified to the correct parent node instead of treating leaf nodes as the final classification ***,error propagation occurs when a misclassification at a parent node propagates down the hierarchy,ultimately leading to inaccurate predictions at the leaf *** address these limitations,we propose an uncertainty-guided HTC depth-aware model called ***,we design an early stopping strategy with uncertainty to identify incomplete matching between text and labels,classifying them into the corresponding parent node *** approach allows us to dynamically determine the classification depth by leveraging evidence to quantify and accumulate *** results show that the proposed DepthMatch outperforms recent strong baselines on four commonly used public datasets:WOS(Web of Science),RCV1.V2(Reuters Corpus Volume I),AAPD(Arxiv Academic Paper Dataset),and ***,on the BGC dataset,it improvesMicro-F1.andMacro-F1.scores by at least 1.09%and 1.74%,respectively.

关键词： Hierarchical text classification incomplete text-label matching uncertainty depth-aware early stopping strategy