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Oscillations of Low-Field Magnetoresistivity of Two-Dimensional Electron Gases in Al_(0.22)Ga_(0.78)N/GaN Heterostructures in a Weak Localization Region

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Chinese Physics Letters 2011年第8期28卷 262-265页

作者： HAN Kui TANG Ning duan jun-xi LU Fang-Chao LIU Yu-Chi SHEN Bo ZHOU Wen-Zheng LIN Tie SUN Lei YU Guo-Lin CHU jun-Hao State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871 National Laboratory for Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083

Low-field magnetotransport properties of two-dimensional electron gases(2DEGs)are investigated in Al_(0.22)Ga_(0.78)N/GaN *** means of a tilting magnetic field,unexpected oscillations of magnetoresistivity are observed in a weak localization *** understanding based on Altshuler–Aronov–Spivak oscillations is proposed for the case of interface disorder in Al_(0.22)Ga_(0.78)N/GaN heterostructures.

关键词： N/Ga resistivity Electron

隐性交易成本与资产定价——基于上证180指数成份股票交易数据的实证研究

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财贸研究 2007年第4期18卷 77-84页

作者：邓可斌段西军广东外语外贸大学国际工商管理学院广东广州510420 中国证监会广东证监局广东广州510120

文章利用上证180指数成份股票的高频数据计算隐性交易成本,探讨其与资产定价的关系。发现:(1)隐性交易成本与换手率、规模和收益率都存在着明显的线性负相关关系。在股票收益率下降时期,隐性交易成本通过流动性深度成本间接影响股票收... 详细信息

文章利用上证180指数成份股票的高频数据计算隐性交易成本,探讨其与资产定价的关系。发现:(1)隐性交易成本与换手率、规模和收益率都存在着明显的线性负相关关系。在股票收益率下降时期,隐性交易成本通过流动性深度成本间接影响股票收益率。(2)较之隐性交易成本,规模因素与换手率因素对收益率的影响有着更好的测度性。很可能是因为这两个因素与流动性深度成本也有着显著相关性。(3)隐性交易成本与规模因素整体上呈线性负相关关系,分段上的关系则很可能是凹函数与凸函数的组合。

关键词：隐性交易成本资产定价市场微观结构

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注浆法处理断桩技术

施工技术 2006年第S2期35卷 47-48页

作者：刘端锋张军中国有色金属工业西安勘察设计研究院陕西西安710054

分析评价了不同原因的断桩处理方法,重点阐明注浆法处理断桩施工工艺,该方法有施工简便、速度快、成本低、效果好等特点。

关键词：断桩处理技术注浆法

桥上纵连板式无砟轨道HRB500钢筋疲劳寿命预测模型试验研究

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湖南大学学报（自然科学版） 2017年第7期44卷 143-149页

作者：徐庆元张泽肖祖材段俊欧熙魏琪娄平中南大学土木工程学院湖南长沙410083

进行了服役期间组合荷载下桥上纵连板式无砟轨道HRB500钢筋随机变幅疲劳应力谱平均应力修正模型和累积损伤模型研究,以便为组合荷载下桥上纵连板式无砟轨道HRB500钢筋疲劳寿命预测模型的建立提供支撑.通过对HRB500钢筋标准试件进行等幅... 详细信息

进行了服役期间组合荷载下桥上纵连板式无砟轨道HRB500钢筋随机变幅疲劳应力谱平均应力修正模型和累积损伤模型研究,以便为组合荷载下桥上纵连板式无砟轨道HRB500钢筋疲劳寿命预测模型的建立提供支撑.通过对HRB500钢筋标准试件进行等幅疲劳试验,研究平均应力对HRB500钢筋疲劳寿命的影响规律,并在此基础上,研究工程上常用的疲劳应力谱平均应力修正模型对服役期间组合荷载下桥上纵连板式无砟轨道HRB500钢筋的适用性;通过对HRB500钢筋标准试件进行三级变幅疲劳试验,分析Miner准则计算服役期间组合荷载下桥上纵连板式无砟轨道HRB500钢筋累积损伤的适用性.研究结果表明,HRB500钢筋标准试件疲劳寿命随平均应力的增大而减小,工程上广泛采用的Goodman模型适用于随机变幅荷载下HRB500钢筋平均应力修正;Miner准则能较好地适用于服役期间组合荷载下桥上纵连板式无砟轨道HRB500钢筋累积损伤计算.

关键词：桥上纵连板式无砟轨道 HRB500钢筋平均应力累积损伤疲劳试验 Miner准则

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu xiaoling Liu Biao Meng Tao Chen Yu Han jun Wang Shibo xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

Reverse modulation of defect density of Ce-MOF-808 by solventassisted ligand exchange for dicyclopentadiene hydrogenation

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Science China Chemistry 2025年

作者： Danfeng Zhao Fajie Hu Rushuo Li xinmeng Xu Zhaokun Wang Zuoshuai xi jun Tong xiubing Huang Ge Wang Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing

Defect engineering is a pivotal strategy for tailoring the electronic structure and physicochemical properties of catalysts, yet the straightforward manipulation of defect density in porous materials presents a current challenge. In this work, we achieved precise control over the coordination unsaturated site（CUS） content and pore architecture of Ce-MOF-808 by employing 2-fluorobenzoic acid（2-FBA） as a modifier. Leveraging the p Kadisparities among three ligands（1,3,5-tricarboxylic benzoic acid,formic acid, and 2-FBA）, we preserved the spn topology of Ce-MOF within an aqueous system, while realizing partial substitution of the auxiliary ligands and saturation of the CUS. The amount of 2-FBA was negatively correlated with the number of ligand defects, and the consequent decrease in Ce3+content and the increase in the number of ligand linkages also induced crystal structure transformation. The modulation of the defect structure was correlated with the catalytic performance of dicyclopentadiene（DCPD） hydrogenation reaction, in which Ce-MMF0.15, constructed by the modulation of 0.15 mol amount of 2-fluorobenzoic acid, exhibited an optimal ligand defect density and micro-mesoporous structure, enabling almost complete conversion of DCPD at 100 ℃ and 2 MPa. This article also elucidates the correlation between the regulation of defect density and the accessibility of frustrated Lewis pair（FLP） active sites, guiding the application of novel porous intrinsic FLP materials in hydrogenation catalysis.

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Potassium ions and cyano group modified g-C3N4 for effective generation of H2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期 192-200页

作者： Dongying Wang Shulan Pu Yongmin Chen Ke Lei Yujie duan Linjiao Mao Xuhui Zeng xi Luo Yuntao Zhang Yuqin Dong Jin Zhong Zhang Yan Sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOH） as an ion *** transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （H2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQY） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （H+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of H2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H2O2generation.

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对中国股市与宏观经济走势异动的观察与机理解释

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广西社会科学 2006年第7期 48-51页

作者：何问陶黄建欢段西军暨南大学经济学院金融系广东广州510632

中国股市与宏观经济走势之间存在异动现象,但是已有的研究并未将异动及其机理解释清楚。基于投资选择与寻租理论的视角,中国股市与宏观经济异动的内在机理可解释为:股市相关制度宽松时,租息率相对较高,资金大量流入股市推动股市走高,但... 详细信息

中国股市与宏观经济走势之间存在异动现象,但是已有的研究并未将异动及其机理解释清楚。基于投资选择与寻租理论的视角,中国股市与宏观经济异动的内在机理可解释为:股市相关制度宽松时,租息率相对较高,资金大量流入股市推动股市走高,但流向产业领域的资金比例减少使得投资不足,导致宏观经济增长放缓;当股市相关制度趋于严格、规范时,资金从股市流向产业领域,推动宏观经济增长加速。

关键词：中国股市宏观经济异动制度寻租

Single-cell omics: experimental workflow, data analyses and applications

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Science China Life Sciences 2025年第1期68卷 5-102页

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu Fu Lei Gu xin Shao Qinqin Wang xin Dong Bin duan Feiyang xing jun Wu Minmin xiao Fangqing Zhao Jing-Dong J.Han Qi Liu xiaohui Fan Chen Li Chenfei Wang Tieliu Shi Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of EducationOrthopaedic DepartmentTongji HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public HealthShanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang University Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesCenter for Quantitative Biology (CQB)Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women's HospitalZhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of StatisticsEast China Normal University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial sc RNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词： single-cell sequencing genome epigenome proteomics metabolomics multimodal spatial transcriptomics CRISPR screening