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Journal of the Operations Research Society of China 2024年第1期12卷 93-108页

作者： guang Zhang jing-Yi Ge Business School University of Shanghai for Science and TechnologyShanghai200093China

A class of cooperative games with graph communication structure is studied in this paper by considering some important players,namely essential *** the assumption that only connected coalitions containing essential players are able to cooperate and obtain their worths,the class of graph games with essential players is proposed as well as an allocation *** proposed value follows the spirit of the Myerson value defined by applying the Shapley value on a modified *** properties,feasible component efficiency,the inessential component property,and fairness,are provided to fully characterize this value,where feasible component efficiency and fairness follows the same ideas of component efficiency and fairness for classical graph games,and the inessential component property says that the total payoffs of the players in a non-feasible component is ***,some computational aspects of the proposed value and comparisons with disjunctive permission value for games with permission structure are also studied,respectively.

关键词： Cooperative game Graph structure Essential player Myerson value Computation Permission structure

Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

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Journal of Iron and Steel Research International 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie Guo Xin-fang Zhang Yi-wa Luo Ye sun jing Guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang Gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials *** effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these *** this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is *** parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

Surface reconstruction of heterostructures in alkaline medium towards enhanced electrocatalytic hydrogen evolution

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Rare Metals 2024年第6期43卷 2636-2647页

作者： Ming-Yang Yang Ji Yuan Xue-Lian Fu jing-jing Chen jing Hu Zhou-guang Lu Chen Liu guangdong Research Center for Interfacial Engineering of Functional Materials Shenzhen Key Laboratory of Polymer Science and TechnologyShenzhen Key Laboratory of Energy Electrocatalytic MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Interfacial Science and Engineering of Materials Department of Materials Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

Constructing heterostructures has proved to be a successful strategy to fabricate electrocatalysts with high efficiency for water ***,the structure evolution in alkaline hydrogen evolution reaction lacks investigation and the specific active center remains ***,we take the well-designed Ni_(3)S_(2)@VO_(2) heterostructures as a model to investigate the electrocatalytic activity and the surface reconstruction process of heterostructure catalysts in alkaline *** Ni_(3)S_(2)@VO_(2) heterostructures,with Ni_(3)S_(2) nanorods as the core and VO_(2) nanoflakes as the shell,coupled with the high conductive Ni_(3)S_(2),the hydrophilic VO_(2) and modulated electronic structures at the interfaces,exhibited prominent activity and superior stability at various current ***,the ex-situ characterizations confirmed that the surface reconstruction from Ni_(3)S_(2)@VO_(2) into Ni_(3)S_(2)@amorphous-Ni(OH)_(2) in alkaline media could optimize the water dissociation barrier and exposed large active area,thereby contributing to improved electrocatalytic *** study not only introduces novel high-performance electrocatalysts for hydrogen evolution reaction(HER),but also provides a new avenue for re-examining hetero-structural catalysts in alkaline solutions.

关键词： Heterostructures Ni_(3)S_(2)@VO_(2) Surface reconstruction Water dissociation Alkaline hydrogen evolution

Friction moment calculation method for tapered roller bearings under combined loads

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Science China(Technological Sciences) 2024年第8期67卷 2565-2578页

作者： LI XinBin LIU jing HUANG SuHe PAN guang School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory for Unmanned Underwater Vehicle Northwestern Polytechnical UniversityXi’an 710072China System Engineering Research Institute Beijing 100094China

Tapered roller bearings(TRBs) can withstand axial loads, radial loads, and overturning moments. The performance, safety, and efficiency of rotating machinery are directly influenced by the friction moments within the TRBs. However, most current research has relied on empirical formulas that focus on axial loads. Additionally, the friction coefficient between the rollers and the inner ring rib has been defined using simple empirical methods. In actual applications, the loads on TRBs are not purely axial or radial, and simple empirical friction coefficients do not adequately account for the varying lubrication conditions. To address this challenge, this study proposes an improved method for calculating the friction moments of TRB under combined axial and radial loads. This study employs a calculation method for sliding friction coefficients that can model dry, boundary, elastohydrodynamic, and mixed lubrication conditions. To demonstrate the advantages of the proposed method, the friction moments obtained using the existing and proposed methods are compared. Additionally, the influence of TRB structural parameters on the friction moment is discussed. An experimental study is conducted to validate the effectiveness of the proposed method. The findings provide valuable insights for designing TRB structural parameters to minimize friction moments.

关键词： tapered roller bearing friction moment structural parameters combined loads

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Identification of FOXO1 as a geroprotector in human synovium through single-nucleus transcriptomic profiling

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Protein & Cell 2024年第6期15卷 441-459页

作者： Feifei Liu Yi Lu Xuebao Wang Shuhui sun Huize Pan Min Wang Zehua Wang Weiqi Zhang Shuai Ma Guoqiang sun Qun Chu Si Wang jing Qu guang-Hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Sports Medicine Department Beijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Division of Life Sciences and Medicine School of Life SciencesUniversity of Science and Technology of ChinaHefei 230001China CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China The Fifth People’s Hospital of Chongqing Chongqing 400062China Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu Hospital Capital Medical UniversityBeijing 100053China Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijing 100053China

The synovium,a thin layer of tissue that is adjacent to the joints and secretes synovial fluid,undergoes changes in aging that contribute to intense shoulder pain and other joint ***,the mechanism underlying human synovial aging remains poorly ***,we generated a comprehensive transcriptomic profile of synovial cells present in the subacromial synovium from young and aged *** delineating aging-related transcriptomic changes across different cell types and their associated regulatory networks,we identified two subsets of mesenchymal stromal cells(MSCs)in human synovium,which are lining and sublining MSCs,and found that angiogenesis and fibrosis-associated genes were upregulated whereas genes associated with cell adhesion and cartilage development were downregulated in aged ***,the specific cell-cell communications in aged synovium mirrors that of aging-related inflammation and tissue remodeling,including vascular hyperplasia and tissue *** particular,we identified forkhead box O1(FOXO1)as one of the major regulons for aging differentially expressed genes(DEGs)in synovial MSCs,and validated its downregulation in both lining and sublining MSC populations of the aged *** human FOXO1-depleted MSCs derived from human embryonic stem cells,we recapitulated the senescent phenotype observed in the subacromial synovium of aged *** data indicate an important role of FOXO1 in the regulation of human synovial ***,our study improves our understanding of synovial aging during joint degeneration,thereby informing the development of novel intervention strategies aimed at rejuvenating the aged joint.

关键词： FOXO1 degeneration inflammation

CRL2^(APPBP2)-mediated TSPYL2 degradation counteracts human mesenchymal stem cell senescence

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Science China(Life Sciences) 2024年第3期67卷 460-474页

作者： Daoyuan Huang Qian Zhao Kuan Yang jinghui Lei Ying jing Hongyu Li Chen Zhang Shuai Ma Shuhui sun Yusheng Cai Guibin Wang jing Qu Weiqi Zhang Si Wang guang-Hui Liu Advanced Innovation Centerfor Human Brain Protection National Clinical Research Centerfor Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Aging Translational MedicineCenter International Centerfor Aging and CancerBejing Municipal GeriatricMedical Research CenterXuanwu HospitalCapital Medical UniversityBeijing 100053China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Beijing Institute for Stem Cell and Regenerative Medicine Beijing100101China CAS Key Laboratory of Genomic and Precision Medicine Bejing Institute of Genomics and China National Center for BioinformationChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration CASBeijing 100101China The Fifth People's Hospital of Chongqing Chongqing 400062China Sino-Danish Cllege University of Chinese Academy of SciencesBeijing101408China National Laboratory of Biomacromolecules CAS Center for Excelence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing100101China State Key Laboratory of Proteomics Beijing Proteome Research CenterNational Center for Protein Sciences(Beijing)Beijing Institute of LifeomicsBeijing 102206China

Cullin-RING E3 ubiquitin ligases(CRLs),the largest family of multi-subunit E3 ubiquitin ligases in eukaryotic cells,represent core cellular machinery for executing protein degradation and maintaining ***,we asked what roles Cullin proteins play in human mesenchymal stem cell(hMSC)homeostasis and *** this end,we conducted a comparative aging phenotype analysis by individually knocking down Cullin members in three senescence models:replicative senescent hMSCs,Hutchinson-Gilford Progeria Syndrome hMSCs,and Werner syndrome *** all family members,we found that CUL2 deficiency rendered hMSCs the most susceptible to *** investigate CUL2-specific underlying mechanisms,we then applied CRISPR/Cas9-mediated gene editing technology to generate CUL2-deficient human embryonic stem cells(hESCs).When we differentiated these into h MSCs,we found that CUL2 deletion markedly accelerates hMSC ***,we identified that CUL2 targets and promotes ubiquitin proteasome-mediated degradation of TSPYL2(a known negative regulator of proliferation)through the substrate receptor protein APPBP2,which in turn downregulates one of the canonical aging marker-P21^(waf1/cip1),and thereby delays *** work provides important insights into how CRL2^(APPBP2)-mediated TSPYL2 degradation counteracts hMSC senescence,providing a molecular basis for directing intervention strategies against aging and aging-related diseases.

关键词： Cullins stem cell senescence aging proteostasis ubiquitination APPBP2 TSPYL2

Analysis of rotor eddy current loss and thermal deformation of magnetic liquid double suspension bearing

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High Technology Letters 2024年第3期30卷 322-332页

作者： LIU Hongmei YANG guang sun Yanan sun Jian WANG Zhe ZHAO Jianhua Shijiazhuang Rail Transit Group Co.Ltd Shijiazhuang 050011P.R.China Shijiazhuang Haishan Industrial Development Co.Ltd Shijiazhuang 050200P.R.China Fluid Power Transmission and Control Laboratory Yanshan UniversityQinhuangdao 066004P.R.China

Magnetic-liquid double suspension bearing(MLDSB)is a new type of suspension bearing based on electromagnetic suspension and supplemented by hydrostatic *** affecting the electromagnetic suspension force,the hydrostatic supporting effect is increased,and the real-time coupling of magnetic and liquid supporting can be ***,due to the high rotation speed,the rotor part produces eddy current loss,resulting in a large temperature rise and large ther-mal deformation,which makes the oil film thickness deviate from the initial *** support and bearing characteristics are seriously ***,this paper intends to explore the internal effects of eddy current loss of the rotor on the temperature rise and thermal deformation of ***,the 2D magnetic flow coupling mathematical model of MLDSB is established,and the eddy current loss distribution characteristics of the rotor are numerically simulated by Maxwell ***,the internal influence of mapping relationship of structural operating parameters such as input current,coil turns and rotor speed on rotor eddy current loss is revealed,and the changing trend of rotor eddy current loss under different design parameters is ***,the eddy cur-rent loss is loaded into the heat transfer finite element calculation model as a heat source,and the temperature rise of the rotor and its thermal deformation are simulated and analyzed,and the influ-ence of eddy current loss on rotor temperature rise and thermal deformation is ***,the pressure-flow curve and the distribution law of the internal flow field are tested by the particle image velocimetry(PIV)*** results show that eddy current loss increases linearly with the in-crease of coil current,coil turns and rotor *** effect of rotational speed on eddy current loss is much higher than that of coil current and coil *** maximum temperature rise,minimum temperature rise and maximum thermal defo

关键词： magnetic-liquid double suspension bearing(MLDSB) oil film thickness cur-rent loss thermal deformation particle image velocimetry(PIV)test

In Situ Growth of 2D Metal-Organic Framework Ion Sieve Interphase for Reversible Zinc Anodes

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 158-166页

作者： sun, jing Jian, Qinping Liu, Bin Lin, Pengzhu Zhao, Tianshou Hong Kong Univ Sci & Technol Dept Mech & Aerosp Engn Kowloon Clear Water Bay Hong Kong Peoples R China Southern Univ Sci & Technol Dept Mech & Energy Engn Shenzhen 518055 Peoples R China

Zinc metal anodes are gaining popularity in aqueous electrochemical energy storage systems for their high safety, cost-effectiveness, and high capacity. However, the service life of zinc metal anodes is severely constrained by critical challenges, including dendrites, water-induced hydrogen evolution, and passivation. In this study, a protective two-dimensional metal-organic framework interphase is in situ constructed on the zinc anode surface with a novel gel vapor deposition method. The ultrathin interphase layer (similar to 1 mu m) is made of layer-stacking 2D nanosheets with angstrom-level pores of around 2.1 angstrom, which serves as an ion sieve to reject large solvent-ion pairs while homogenizes the transport of partially desolvated zinc ions, contributing to a uniform and highly reversible zinc deposition. With the shielding of the interphase layer, an ultra-stable zinc plating/stripping is achieved in symmetric cells with cycling over 1000 h at 0.5 mA cm(-2) and similar to 700 h at 1 mA cm(-2), far exceeding that of the bare zinc anodes (250 and 70 h). Furthermore, as a proof-of-concept demonstration, the full cell paired with MnO2 cathode demonstrates improved rate performances and stable cycling (1200 cycles at 1 A g(-1)). This work provides fresh insights into interphase design to promote the performance of zinc metal anodes.

关键词： 2D MOF desolvation interphase ion sieve zinc anode DEPOSITION KINETICS CRYSTAL

Optical grade (Gd_(0.95-x)Lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) ceramics with near-zero optical loss: Effects of Lu^(3+) doping on structural feature, microstructure evolution, and far-red luminescence

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Journal of Advanced Ceramics 2024年第1期13卷 113-123页

作者： Zhigang sun Ji-guang Li Huiyu Qian Yoshio Sakka Tohru SSuzuki Bin Lu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Research Center for Electronic and Optical Materials National Institute for Materials ScienceIbaraki 305-0044Japan Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province Ningbo 315211China

A chemical co-precipitation strategy was employed to synthesize a series of(Gd_(0.95−x)Lu_(x)Eu_(0.05))_(3)Al_(5)O_(12)(x=0.1−0.95)powder phosphors,followed by vacuum sintering to achieve transparent garnet ceramic *** density functional theory indicated Lu_(3)Al_(5)O_(12) was formed in priority compared with Gd_(3)Al_(5)O_(12) during solid-phase *** high-temperature sintering,the Lu^(3+)substitution for Gd^(3+)suppressed point mass diffusion leading to a smaller grain *** in-line transmittances of bulk specimens with x=0.1,0.3,0.5,0.7,and 0.95 nm were~83.5%,80.1%,68.8%,73.7%,and 82.2%at 710 nm(Eu^(3+)emission center),respectively,among which the sample of x=0.1 exhibited the optical grade with near-zero optical loss in agreement with the defect-free single crystal(~100%of the theoretical transmittance).The resulting particle and ceramic materials both presented characteristic Eu^(3+)emission arising from 5D0→7FJ(J=1−4)transition,where the dominant far-red emission at~710 nm arising from ^(5)D_(0)→^(7)F_(4) transition overlapped with the absorption of phytochrome(PFR).The photoluminescence excitation and photoluminescence intensities of(Gd_(0.95−x)Lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) powders and ceramics generally increased at a higher Gd^(3+)/Lu^(3+)***^(3+)dopants delayed the fluorescence lifetime while the bulk samples had shorter lifetime compared to the particle *** transparent(Gd_(0.85)Lu_(0.1)Eu_(0.05))3Al_(5)O_(12) ceramic phosphor exhibited good thermal stability with a high thermal quenching temperature above 533 *** designed ceramic phosphor-converted light-emitting diode had a saturation injection current of 435 mA and a current-dependent color rendering *** importantly,our report marked the developmental stage of transparent ceramic materials towards zero optical loss.

关键词： transparent ceramics garnet phosphors light-emitting diode(LED) optical properties Gibbs free energy