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Science China Chemistry 2021年第5期64卷 734-738页

作者： Yang Shi Gui-Xian Liu Jing wan Rui Wen Li-jun wan Key Laboratory of Molecular Nanostructure and Nanotechnology Beijing National Laboratory for Molecular SciencesCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of the Chinese Academy of Sciences Beijing 100049China

The solid electrolyte interphase(SEI)has caught considerable attention as a pivotal factor affecting lithium(Li)metal battery ***,the understanding of the interfacial evolution and properties of the on-site formed SEI shells on Li deposits during cycling is still at a preliminary ***,we provide a straightforward visualized evidence of SEI shells’evolution during Li deposition/stripping to reveal anode degradation via in-situ atomic force microscopy(AFM).Nucleation and growth of quasi-spherical Li particles are observed on a Cu substrate,followed by Li stripping and collapse of SEI *** the subsequent cycling,new Li deposits tend to nucleate at pristine sites with fresh SEI shells forming on *** previously collapsed SEI shells accumulate to increase interface impedance,eventually leading to capacity *** the electrochemical processes and interfacial degradation at the nanoscale will enrich fundamental comprehension and further guide improvement strategies of Li metal anodes.

关键词： solid electrolyte interphase shell lithium deposition and stripping interfacial degradation lithium metal battery

Construction of n-sided polygonal spline element using area coordinates and B-net method

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Acta Mechanica Sinica 2010年第5期26卷 685-693页

作者： Juan Chen Chong-jun Li wan-Ji Chen School of Mathematical Sciences Dalian University of Technology 116024 Dalian China State Key Laboratory for Structural Analysisof Industrial Equipment Dalian University of Technology116024 Dalian China Institute for Structural Analysis of Aerocraft Shenyang Institute of Aeronautical Engineering110136 Shenyang China

In general, triangular and quadrilateral elements are commonly applied in two-dimensional finite element methods. If they are used to compute polycrystalline materials, the cost of computation can be quite significant. Polygonal elements can do well in simulation of the materials behavior and provide greater flexibility for the meshing of complex geometries. Hence, the study on the polygonal element is a very useful and necessary part in the finite element method. In this paper, an n-sided polygonal element based on quadratic spline interpolant, denoted by PS2 element, is presented using the triangular area coordinates and the B-net method. The PS2 element is conforming and can exactly model the quadratic field. It is valid for both convex and non-convex polygonal element, and insensitive to mesh distortions. In addition, no mapping or coordinate transformation is required and thus no Jacobian matrix and its inverse are evaluated. Some appropriate examples are employed to evaluate the performance of the proposed element.

关键词： Finite element method n-sided polygonalelement - Bivariate spline interpolation The second ordercompleteness

Limited Effect of Twin Boundaries on Radiation Damage

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 72-78页

作者： Jin Gao Zhi-jun Liu Fa-Rong wan Department of Materials Physics and Chemistry School of Materials Science and EngineeringUniversity of Science and Technology Beijing

The different influences of the general grain boundary and the twin boundary on the cavity formation were investigated in copper irradiated by helium at room temperature. Large number of the cavities with sizes smaller than 5 nm formed after irradiation, which were almost homogenously distributed inside the grains. However, the distribution of the cavities varied near the general grain boundary and the twin boundary. Cavities-depleted zone was readily observed near the general grain boundaries, which was rarely observed near the twin boundaries. Meanwhile, decoration of dense cavities within the grain boundary plane was observed. The results suggested the limited influence of the twin boundaries as the point defect sinks compared with the general grain boundaries.

关键词： Transmission electron microscopy Cavities Cavities-depleted zone General grainboundary Twin boundary

A 3D pyramid spline element

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Acta Mechanica Sinica 2011年第6期27卷 986-993页

作者： Juan Chen Chong-jun Li wan-Ji Chen School of Mathematics and Quantitative Economics Dongbei University of Finance and Economics 116025 Dalian China School of Mathematical Sciences Dalian University of Technology116024 Dalian China Key Laboratory of Liaoning Province for Composite Structural Analysis of Aerocraft and Simulation Shenyang Aerospace University 110136 Shenyang China State Key Laboratory for Structural Analysis of Industrial Equipment Dalian University of Technology 116024 Dalian China

In this paper,a 13-node pyramid spline element is derived by using the tetrahedron volume coordinates and the B-net method,which achieves the second order completeness in Cartesian *** appropriate examples were employed to evaluate the performance of the proposed *** numerical results show that the spline element has much better performance compared with the isoparametric serendipity element Q20 and its degenerate pyramid element P13 especially when mesh is distorted,and it is comparable to the Lagrange element *** has been demonstrated that the spline finite element method is an efficient tool for developing high accuracy elements.

关键词： Spline finite element Pyramid element The second order completeness B-net method

定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLO W_(6)C_(6)团簇

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Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao jun Liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

Changes in extracellular matrix in different stages of colorectal cancer and their effects on proliferation of cancer cells

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World Journal of Gastrointestinal Oncology 2020年第3期12卷 267-275页

作者： Zhu-Lin Li Zhen-jun wang Guang-Hui wei Yong Yang Xiao-wan wang Department of General Surgery Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China Institute of Basic Medical Sciences Chinese Academy of Medical SciencesBeijing 100005China

BACKGROUND The extracellular matrix is the main component of the tumor *** matrix remodels with the oncogenesis and development of *** studies usually focused on the changes of proteins in normal colorectal tissues and colorectal *** is known about the changes in the extracellular matrix in different stages of colorectal cancer and the effects of these changes on the development of this *** To test the changes of type I collagen,type IV collagen,matrix metalloproteinase-2(MMP-2),matrix metalloproteinase-9(MMP-9),and tissue inhibitor of metalloproteinase-3(TIMP-3)in different stages of colorectal cancer and the effects of these changes on the proliferation of cancer *** The extracellular matrix from various stages of colorectal cancer and normal colon tissue was obtained by using acellular *** used proteomics to detect the differential expression of proteins between normal colon tissues and colorectal cancer tissues,and then we used Western blot to observe their expression in each stage of colorectal cancer and in normal colon *** coculturing the extracellular matrix and HT29 colon cancer cells in vivo and in vitro,we tested the cancer cell proliferation rate in vitro by methyl thiazolyl tetrazolium(MTT)assay and in vivo by measuring the tumor *** The expression of type I collagen and MMP-2 increased with increased tumor *** expression of MMP-9 was higher in colorectal cancer tissues and was highest in stage III *** expression of type IV collagen and TIMP-3 decreased with increased tumor *** proliferation rate of cancer cells in the extracellular matrix of colorectal cancer was higher than that in the extracellular matrix of the normal *** These data suggest that the extracellular matrix structure and composition become disorganized during the development of tumors,which is more conducive for the growth of cancer cells.

关键词： Colorectal cancer Extracellular matrix MMP Proliferation Collagen TIMP

Molecular characterization,spatial-temporal expression and magnetic response patterns of iron-sulfur cluster assembly1(IscA1)in the rice planthopper,Nilaparvata lugens

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Insect Science 2019年第3期26卷 413-423页

作者： Jing-Jing Xu Ying-Chao Zhang Jian-Qi Wu wei-Hong wang Yue Li Gui-jun wan Fa-jun Chen Gregory A. Sword wei-Dong Pan Beijing Key Laboratory of Bioelectromagnetics Institute of Electrical EngineeringChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina Department of Entomology College of Plant ProtectionNanjing Agricultural UniversityNanjingChina Department of Entomology Texas A&M UniversityCollege StationTXUSA

The mechanisms of magnetoreception have been proposed as the magnetitebased, the chemical radical-pair and biocompass model, in which magnetite particles, the cryptochrome (Cry) or iron-sulfur cluster assembly 1 (IscA1) may be involved. However, little is known about the association among the molecules. Here we investigated the molecular characterization and the mRNA expression of IscA1 in different developmental stages, tissues and magnetic fields in the migratory brown planthopper (BPH), Nilaparvata lugens. NlIscA1 contains an open reading frame of 390 bp, encoding amino acids of 129, with the predicted molecular weight of 14.0 kDa and the isoelectric point of 9.10. Well-conserved Fe-S cluster binding sites were observed in the predicted protein. Phylogenetic analysis demonstrated NlIscA1 to be clustered into the insect's IscA1. NlIscA1 showed up-regulated mRNA expression during the period of migration. The mRNA expression of NlIscA1 could be detected in all the three tissues of head, thorax and abdomen, with the highest expression level in the abdomen. For the macropterous migratory Nilaparvata lugens, mRNA expression of NlIscA1 and N. lugens cryptochromel (Nlcry1) were up-regulated under the magnetic fields of 5 Gauss and 10 Gauss in strength (vs. local geomagnetic field), while N. lugens cryptochrome 2 (Nlcry2) remained stable. For the brachyterous non-migratory Nilaparvata lugens, no significant changes were found in mRNA expression of NlIscA1, Nlcry1 and Nlcry2 among different magnetic fields. These findings preliminarily reveal that the expression of NlIscA1 and Nlcry1 exhibited coordinated responses to the magnetic field. It suggests some potential associations among the putative magneto-sensitive molecules of cryptochrome and iron-sulfur cluster assembly.

关键词： cryptochrome iron-sulfur cluster assemblyl magnetic field migratory Nilaparvata lugens

Valley switch effect in anα-T3 lattice-based superconducting interferometer

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Chinese Physics B 2024年第11期33卷 372-377页

作者： Ya-jun wei jun wang School of Physics Southeast UniversityNanjing 210096China

Dirac electrons possess a valley degree of freedom,which is currently under investigation as a potential information *** propose an approach to generate and manipulate the valley-switching current(VSC)through Andreev reflection using an interferometer-based superconductor hybrid *** interferometer comprises a ring-shaped structure formed by topological kink states in the a-T3 lattice via carefully designed electrostatic *** results demonstrate the feasibility of achieving a fully polarized VSC in this device without contamination from cotunneling electrons sharing the same valley as the incident ***,we show that control over the fully polarized VSC can be achieved by applying a nonlocal gate voltage or modifying the global parameter *** former alters the dynamic phase of electrons while the latter provides an a-dependent Berry phase,both directly influencing quantum interference and thereby affecting performance in terms of generating and manipulating VSC,crucial for advancements in valleytronics.

关键词： valley switch effect valleytronics Andreev reflection a-T3 lattice

Superiority of empirical Bayes estimator of the mean vector in multivariate normal distribution

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Science China Mathematics 2016年第6期59卷 1175-1186页

作者： YUAN Min wan ChongLi wei LaiSheng School of Mathematics University of Science and Technology of China School of Management University of Science and Technology of China

In this paper, the Bayes estimator and the parametric empirical Bayes estimator(PEBE) of mean vector in multivariate normal distribution are obtained. The superiority of the PEBE over the minimum variance unbiased estimator(MVUE) and a revised James-Stein estimators(RJSE) are investigated respectively under mean square error(MSE) criterion. Extensive simulations are conducted to show that performance of the PEBE is optimal among these three estimators under the MSE criterion.

关键词： multivariate normal distribution mean vector MVUE PEBE RJSE mean square error