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Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da wan Shuwei Tang Shulin Bai Xiaodong Li Peng Ai wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

A New foraminiferal Bioindicator for Long-Term Heat Stress on Coral Reefs

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journal of Earth Science 2022年第6期33卷 1451-1459页

作者： Alexander f.Humphreys Sam j.Purkis Chuyan wan Matthew Aldrich Sarah Nichols jazmin Garza Rosenstiel School of Marine and Atmospheric Science Department of Marine GeosciencesUniversity of MiamiMiamiFL33149USA Khaled bin Sultan Living Oceans foundation AnnapolisMD21403USA Department of Earth and Planetary Sciences Northwestern UniversityEvanstonIL60208USA

Coral reefs are in terminal *** conservation to be effective,naturally depauperate reefs must be distinguished from those recently degraded by *** reef monitoring is time consuming and lacks the longevity to make this *** in using foraminifera as bioindicators for reef health has hitherto levered their response to *** ocean heat waves are the dominant driver of coral bleaching and death,there is compelling motivation to develop new foraminiferal bioindicators that inform on temperature stress over meaningful *** study focuses on identifying which foraminifera respond systematically to the temperature stress that kills *** models were used to compare endosymbiont-bearing foraminiferal families,collected along a heat-stress gradient spanning the Solomon Islands and New Caledonia,to live coral cover at the same *** indicate that Amphisteginidae foraminifera and coral cover show a significant decline in abundance as heat stress increases along the transect ***,ocean productivity and salinity,both recognized environmental influences on foraminifera,are shown to be subordinate to temperature in their sway of this ecological *** findings indicate the potential for using foraminifera to develop new indices capable of quantifying long-term thermal impacts on reefs.

关键词： foraminifera bioindicator corals bleaching degree heating week foRAM Index

Compton profiles of NiO and TiO_2 obtained from first principles GWA spectral function

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Chinese Physics B 2016年第6期25卷 407-415页

作者： S M Khidzir M f M Halid W A T wan Abdullah Department of Physics Universiti of Malaya

In this work,we first use momentum density studies to understand strongly correlated electron behavior,which is typically seen in transition metal *** observe that correlated electron behavior as seen in bulk NiO is due to the fermi break located in the middle of overlapping spectral functions obtained from a GW（G is Green’s function and W is the screened Coulomb interaction） approximation（GWA） calculation while in the case of TiO2 we can see that the origin of the constant momentum distribution in lower momenta is due to a pile up of spectra before the fermi *** observations are then used to compare our calculated Compton profiles with previous experimental studies of fukamachi and *** calculations for NiO are observed to follow the same trend as the experimental profile but it is seen to have a wide difference in the case of TiO2 before the fermi *** ground state momentum densities differ significantly from the quasiparticle momentum density,thus stressing the importance of the quasiparticle wave function as the input for the study of charge density and the electron localization *** we perform a calculation of the quasiparticle renormalization function,giving a quantitative description of the discontinuity of the GWA momentum density.

关键词： elastic and Compton scattering density functional theory local density approximation gradient and other corrections elements oxides nitrides borides carbides chalcogenides

Effect of Y content and equal channel angular pressing on the microstructure, texture and mechanical property of extruded Mg-Y alloys

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journal of Magnesium and Alloys 2022年第1期10卷 210-224页

作者： W.Yang G.f.Quan B.ji Y.f.wan H.Zhou j.Zheng D.D.Yin Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengduSichuan 610031China Nano and Heterogeneous Materials Center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China International joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringShenyang National Laboratory for Materials ScienceChongqing UniversityChongqing 400044China

The microstructure, texture and mechanical property evolution of the extruded Mg-x Y(x = 1, 5 wt.%) alloys during equal channel angular pressing(ECAP) were systematically investigated using an optical microscope, electron backscatter diffraction(EBSD) and uniaxial tensile test. The Mg-Y alloys exhibited a weakened basal texture before the ECAP, and the texture was further weakened with the max basal poles dispersed along ~45° between the extrusion direction and the transverse direction after the ECAP. The Mg-5 Y alloys always exhibited a finer grain size comparing to that of Mg-1 Y for the same ECAP process. With a proper ECAP process, both the strength and elongation of Mg-5 Y alloy could be improved simultaneously after the ECAP, i.e., the yield strength(273.9 ± 1.2 MPa), ultimate strength(306.4 ± 3.0 MPa),and elongation(23.9 ± 1.0%) were increased by 10%, 6%, and 72%, respectively, comparing to that before the ECAP. This was considered to be arose from the combined effects of grain refinement, significant improved microstructure homogeneity and solid solution *** addition, it was found that Mg-Y alloy with better comprehensive properties could be obtained by the decreasing-temperature ECAP processes. The yield strength-grain size relationship could be well described by the Hall-Petch relation for all the ECAPed Mg-Y alloys,which was consistent with that the texture changes did not significantly affect the average Schmid factors of basal, prismatic and pyramidal slips for both Mg-Y alloys.

关键词： Mg-RE alloy Equal channel angular pressing Texture Mechanical property

Effect of scanning strategy on grain structure and crystallographic texture of Inconel 718 processed by selective laser melting

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journal of Materials Science & Technology 2018年第10期34卷 1799-1804页

作者： H.Y. wan Z.j. Zhou C.P. Li G.f. Chen G.P. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials & Manufacturing Qualification Group Corporate Technology Siemens Ltd. Beijing 100102 China

Two types of scanning strategies were adopted to study the effect of scanning strategy on grain structure and crystallographic texture of selective laser melted （SLM） Inconel 718. The results show that bidirec-tional scanning without and with a 90°-rotation for every layer produced the bimodal grain structure and the directional columnar grain structure, respectively. Controlling the heat flux direction between the successive layers via scanning strategy enabled the formation of such different grain structures. fur-thermore, when the 90°-rotation was applied, the competitive grain growth mechanism became more pronounced and the strong cube texture developed.

关键词： Selective laser melting Additive manufacturing Scanning strategy Texture Grain structure

Cellular senescence in musculoskeletal homeostasis,diseases,and regeneration

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Bone Research 2021年第4期9卷 444-455页

作者： Mei wan Elise f.Gray-Gaillard jennifer H.Elisseeff Department of Orthopaedic Surgery The Johns Hopkins University School of MedicineBaltimoreMDUSA Translational Tissue Engineering Center Wilmer Eye Institute and the Department of Biomedical EngineeringThe Johns Hopkins UniversityBaltimoreMDUSA

Emerging insights into cellular senescence highlight the relevance of senescence in musculoskeletal disorders,which represent the leading global cause of *** senescence was initially described by Hayflick et *** 1961 as an irreversible nondividing state in in vitro cell culture *** now know that cellular senescence can occur in vivo in response to various stressors as a heterogeneous and tissue-specific cell state with a secretome phenotype acquired after the initial growth *** the past two decades,compelling evidence from preclinical models and human data show an accumulation of senescent cells in many components of the musculoskeletal *** senescence is therefore a defining feature of age-related musculoskeletal disorders,and targeted elimination of these cells has emerged recently as a promising therapeutic approach to ameliorate tissue damage and promote repair and regeneration of the skeleton and skeletal *** this review,we summarize evidence of the role of senescent cells in the maintenance of bone homeostasis during childhood and their contribution to the pathogenesis of chronic musculoskeletal disorders,including osteoporosis,osteoarthritis,and *** highlight the diversity of the senescent cells in the microenvironment of bone,joint,and skeletal muscle tissue,as well as the mechanisms by which these senescent cells are involved in musculoskeletal *** addition,we discuss how identifying and targeting senescent cells might positively affect pathologic progression and musculoskeletal system regeneration.

关键词： skeletal homeostasis dividing

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论中国式现代化辩证逻辑的五重向度

中国矿业大学学报（社会科学版） 2025年第1期27卷 13-26页

作者：万舒全辽宁中医药大学马克思主义学院

党的二十大报告系统阐述了中国式现代化理论,蕴含着深刻的辩证逻辑。中国式现代化的辩证逻辑主要表现为以人口数量与质量的辩证运动提升中国式现代化的主体根基、以先富与共富的辩证运动激发中国式现代化的创造潜能、以物质文明与精神... 详细信息

党的二十大报告系统阐述了中国式现代化理论,蕴含着深刻的辩证逻辑。中国式现代化的辩证逻辑主要表现为以人口数量与质量的辩证运动提升中国式现代化的主体根基、以先富与共富的辩证运动激发中国式现代化的创造潜能、以物质文明与精神文明的辩证运动推进中国式现代化全面发展、以人与自然的辩证运动深化中国式现代化的生态建设、以自身发展与世界发展的辩证运动实现中国式现代化的世界意义。中国式现代化的辩证逻辑是中国式现代化理论的思想精髓,是指导我国社会主义现代化建设的智慧来源,是全面推进中华民族伟大复兴的方法指导。深入研究和阐释中国式现代化的辩证逻辑对于我们深刻领悟党的二十大精神、准确理解中国式现代化理论和推进我国社会主义现代化进程都具有重要意义。

关键词：中国式现代化辩证逻辑党的二十大

基于感性工学和模糊层次分析法的汽车皮革座椅肌理设计研究

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皮革科学与工程 2025年第1期35卷 98-106页

作者：万青蓝武月琴西华大学美术与设计学院四川成都610039

为深入了解消费者对汽车皮革座椅的感性需求,选取25~44岁消费者进行实验研究。首先通过调研、焦点小组等方法选取4对感性词汇:商务/运动、高端/经济、传统/现代、复杂/简约;借助形态分析法解构汽车皮革座椅肌理要素,获得色彩、光泽、纹... 详细信息

为深入了解消费者对汽车皮革座椅的感性需求,选取25~44岁消费者进行实验研究。首先通过调研、焦点小组等方法选取4对感性词汇:商务/运动、高端/经济、传统/现代、复杂/简约;借助形态分析法解构汽车皮革座椅肌理要素,获得色彩、光泽、纹理、图案、质感五类肌理形式;其次运用模糊层次分析法构建层次指标体系与模糊函数评价矩阵,量化消费者感性需求;进一步分析用户感性意向与肌理设计各元素之间的相关性,提出符合用户感性需求的汽车皮革座椅肌理设计元素组合。并将代表特殊感性意向的肌理元素运用到汽车皮革座椅设计中,以期为汽车座椅颜色、材料、表面处理提供参考。

关键词：皮革肌理汽车座椅产品设计感性工学模糊层次分析法

Numerical simulation of local and global mixing/segregation characteristics in a gas–solid fluidized bed

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Chinese journal of Chemical Engineering 2022年第4期35卷 72-86页

作者： Zhen wan Youjun Lu State Key Laboratory of Multiphase flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

Researches on solids mixing and segregation are of great significance for the operation and design of fluidized bed *** this paper,the local and global mixing and segregation characteristics of binary mixtures were investigated in a gas–solid fluidized bed by computational fluid dynamics-discrete element method(CfD-DEM)coupled approach.A methodology based on solids mixing entropy was developed to quantitatively calculate the mixing degree and time of the *** mixing curves of global mixing entropy were acquired,and the distribution maps of local mixing entropy and mixing time were also *** comparing different operating conditions,the effects of superficial gas velocity,particle density ratio and size ratio on mixing/segregation behavior were *** showed that for the partial mixing state,the fluidized bed can be divided into three parts along the bed height:complete segregation area,transition area and stable mixing *** areas showed different mixing/segregation *** gas velocity promoted the local and global mixing of binary *** increase in particle density ratio and size ratio enlarged the complete segregation area,reduced the mixing degree and increased the mixing time in the stable mixing area.

关键词： Discrete element method Solids mixing Binary mixtures fluidized bed