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Fe_(n)Mo_(38-n)(n=0-38)及Fe_(n)Mo_(55-n)(n=0-55)双金属团簇的结构演化和基态能量

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原子与分子物理学报 2025年第3期42卷 85-93页

作者：郑琪琪陈轩程彪段海明新疆大学物理科学与技术学院乌鲁木齐830017

基于半经验的Gupta多体势,采用遗传算法及分子动力学淬火算法,系统研究了(FeMo)m(m=38及55)双金属团簇的基态结构及其能量.结果表明:对于Fe_(n)Mo_(38-n)(n=0-38)团簇,随Fe原子数的增加,Fe原子优先占据团簇表面再占据内部,其基态构型存... 详细信息

基于半经验的Gupta多体势,采用遗传算法及分子动力学淬火算法,系统研究了(FeMo)m(m=38及55)双金属团簇的基态结构及其能量.结果表明:对于Fe_(n)Mo_(38-n)(n=0-38)团簇,随Fe原子数的增加,Fe原子优先占据团簇表面再占据内部,其基态构型存在类O_(h)结构、类I_(h)结构和无序结构间的竞争.对于Fe_(n)Mo_(55-n)(n=0-55)团簇,随Fe原子数的增加,Fe原子优先占据团簇中心位置,再依次占据表面顶点、棱边和次外层,双金属团簇基态构型主要体现为在Mackay二十面体基础上的结构畸变.Fe_(24)Mo_(14),Fe_(13)Mo_(42)和Fe_(43)Mo_(12)为幻数结构团簇,研究发现双金属团簇幻数成因不能通过单质团簇常用的平均配位数和平均键长模型解释,它更多的归咎于组分效应导致的结构高对称性.

关键词：双金属团簇结构和能量淬火算法遗传算法

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Fe_(n)Co_(55-n)与Co_(n)Mo_(55-n)(n=0~55)团簇基态的能量与结构演化

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原子与分子物理学报 2025年第5期42卷 57-66页

作者：程彪郑琪琪陈轩段海明新疆大学物理科学与技术学院乌鲁木齐830049

采用半经验的Gupta多体势函数结合遗传算法及分子动力学淬火算法,系统研究了Co_(n)Mo_(55-n)(n=0~55)与Fe_(n)Co_(55-n)(n=0~55)团簇的基态结构与能量.通过分析基态结构的相似函数、质心间距、平均键长、平均原子配位数、平均结合能、... 详细信息

采用半经验的Gupta多体势函数结合遗传算法及分子动力学淬火算法,系统研究了Co_(n)Mo_(55-n)(n=0~55)与Fe_(n)Co_(55-n)(n=0~55)团簇的基态结构与能量.通过分析基态结构的相似函数、质心间距、平均键长、平均原子配位数、平均结合能、混合能与二阶差分能.探究了团簇基态的结构特征及稳定性与团簇所含元素种类及组分的关联.结果表明:对Co-Mo混合团簇,随Co原子数目增加,Co原子依次占据团簇中心与最外层顶点,混合团簇逐渐出现组分偏析与无序现象;对Fe-Co混合团簇,基态结构主体上均体现为围绕Mackay二十面体构型的结构畸变,随Fe原子含量增加,Fe原子先占据团簇外表面顶点位置直到全部包裹Co原子,逐渐形成核壳式结构;Co_(13)Mo_(42)与Fe_(42)Co_(13)是幻数结构团簇,研究发现组分效应导致的团簇高对称性相比团簇平均键长与平均原子配位数更能解释幻数结构的成因.

关键词：遗传算法淬火算法双金属团簇基态结构

基于事故致因“2-4”模型的高校实验室安全体系化建设探究

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价值工程 2025年第1期44卷 1-4页

作者：安启启张翌兰州资源环境职业技术大学兰州730021

文章对近十年内发生的30起典型高校实验室安全事故进行了深入分析,研究发现,高校实验室爆炸事故占比较为突出,其次是火灾事故。此外,结合典型事故致因分析,文章基于“2-4”事故致因模型,从基层面、管理层面和外部层面三个维度出发提出... 详细信息

文章对近十年内发生的30起典型高校实验室安全事故进行了深入分析,研究发现,高校实验室爆炸事故占比较为突出,其次是火灾事故。此外,结合典型事故致因分析,文章基于“2-4”事故致因模型,从基层面、管理层面和外部层面三个维度出发提出了一个全面构建高校实验室安全管理体系的思路。这一体系的构建不仅为高校实验室的安全管理提供了科学参考,也为高校的科研和人才培养工作提供了坚实的保障。

关键词：事故致因模型高校实验室安全管理

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Thermodynamic Perturbation Theory for Solid-Liquid Phase Transition of Lennard-Jones Model

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Communications in Theoretical Physics 2004年第2X期42卷 285-289页

作者： ZHOUShi-qi ZHANGXiao-qi ResearchInstituteofModernStatisticalMechanics ZhuzhouInstituteofTechnologyZhuzhou412008China

Both a free volume approach for Helmholtz free energy and a theoretically-based fitted formula for radial distribution function (rdf) of hard sphere solid are employed to describe the Helmholtz free energy of Lennard-Jones solid in the framework of the first order thermodynamic perturbation theory, which also is employed for the uniform LennardJones fluid. The dividing of the Lennard-Jones potential follows from the WCA prescription, but the specification of the equivalent hard sphere diameter is determined by a simple iteration procedure devised originally for liquid state, but extended to solid state in the present study. Two hundred sheiks are used in the rdf to get an accurate perturbation *** present approach is very accurate for the description of excess Helmholtz free energy of LJ solid, but shows some deviation from the simulation for excess Helmholtz free energy of uniform LJ fluid when the reduced temperature kT/ε is higher then 5. The present approach is satisfactory for description of solid-liquid phase transition of the Lennard-Jones model.

关键词：热力学微扰理论固态-液态转变亥姆霍兹自由能 Lennard-Jones模型

Adaptive sampling for corrugated plate digitization using a laser displacement sensor

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Science China(Technological Sciences) 2024年第5期67卷 1510-1523页

作者： WU ChengXing qi qi CHEN BaiJin YANG JiXiang DING Han State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

The surface quality of a corrugated plate directly determines the heat transfer property of the thermal power mechanical *** detection methods are impractical for real-world production,being slow and *** contrast,the point laser displacement sensor,employing the optical triangle method,emerges as a promising device for assessing parts with variable curvature and highly reflective *** its benefits,high-density sampling by an innate frequency introduces challenges such as data redundancy and a poor signal-to-noise ratio,potentially affecting the efficiency and precision of subsequent data *** address these challenges,adjustable frequency data sampling has been developed for this sensor,allowing adaptive sampling for corrugated plate *** process begins with surface digitization to extract discrete points,which are transformed into intersection curves using the B-spline fitting ***,dominant points are identified,considering multigeometric constraints for curvature and arch ***,the sampling signal is adjusted based on the distribution information of dominant *** results indicate that the proposed method effectively minimizes redundant sampling without compromising the accurate capture of essential geometric features.

关键词： corrugated plate laser displacement sensor adaptive sampling dominant point curvature arch height

2D Janus polymer nanosheets for enhancing oil recovery:From material ppreparation to property evaluation

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Petroleum Science 2023年第3期20卷 1584-1597页

作者： Hao Shen Zi-Hao Yang Guan-Zhong Wang Yi-Lin Xiong qi-Chao Lv qi Cao qi-qi Niu Yi-Bo Wang Zhao-xia Dong Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Bejing102249China Sinopec Zhenhai Refining and Chemical Company Ningbo315207ZhejiangChina Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina School of Energy Resources China University of Geosciences(Bejing)Bejing100083China

Janus amphiphilic polymer nanosheets(JAPNs)with anisotropic morphology and distinctive perfor-mance have aroused widespread ***,due to the difficulty in synthesis and poor dispersion stability,JAPNs have been scarcely reported in the field of enhancing oil recovery(EOR).Herein,a kind of organic-based flexible JAPNs was prepared by paraffin emulsion *** lateral sizes of JAPNs were ranging from hundreds of nanometers to several micrometers and the thickness was about 3 *** organic-based nanosheets were equipped with remarkably flexible structures,which could improve their injection *** dispersion and interfacial properties of JAPNs were studied *** modification of crosslinking agent containing multiple amino groups,the JAPNs had excellent hydro-philicity and salt resistance compared with conventional inorganic or composite *** settling time of nanosuspension with NaCl and CaCl_(2) at a low salinity of 1000 mg/L was over 240 *** value could also remain 124 h under the salinity of 10,000 mg/L *** the dual functionalities of Janus amphiphilic nature and nanoparticles'Pickering effect,JAPNs could change rock wettability and form emulsions as"colloidal surfactants",In particular,a new technology called optical microrheology was pioneered to explore the destabilization state of nanosuspensions for the first *** precipitation lagged behind aggregation,especially for stable suspension systems,the onset of the unstable behavior was difficult to be detected by conventional methods,which should be the indicator of reduced effec-tiveness for nanofluid *** addition,the oil displacement experiments demonstrated that the JAPNs could enhance oil recovery by 17.14%under an ultra-low concentration of 0.005%and were more suitable for low permeability *** findings can help for a better understanding of the material preparation of polymer *** also hope that this study could shed more light

关键词： 2D materials Polymer nanosheets Enhance oil recovery Janus nature Amphiphilic property

Photometric investigation and orbital period analyses of the W UMa binaries FP Lyn, FV CVn and V354 UMa

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Research in Astronomy and Astrophysics 2019年第7期19卷 103-114页

作者： Raul Michel qi-qi Xia Jesus Higuera1 Observatorio Astronomico Nacional Instituto de AstronomíaUniversidad Nacional Autońoma de MéxicoApartado Postal 877EnsenadaB.C.22830Mexico Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

New light curves and photometric solutions of FP Lyn,FV CVn and V354 UMa are *** found that these three systems are W-subtype shallow contact *** addition,it is obvious that the light curves of FP Lyn and V354 UMa are ***,a hot spot was added on the primary star of FP Lyn and a dark spot was added on the secondary star of V354 *** the same time,we added a third light to the photometric solution of FP Lyn for the final *** obtained mass ratios and fill-out factors are q = 1.153 and f = 13.4% for FP Lyn,q = 1.075 and f = 4.6% for FV CVn,and q = 3.623 and f = 10.7% for V354 UMa *** investigations of orbital period for these three systems indicate that the periods are *** Lyn and V354 UMa were discovered to have secularly increasing components with rates of dp/dt = 4.19 ×10^-7 dyr^-1 and dp/dt = 7.70 ×10^-7 dyr^-1 respectively,which are feasibly caused by conservative mass transfer from the less massive component to the more massive *** addition,some variable components were discovered for FV CVn,including a rate of dp/dt =-1.13 ×10^-6 dyr^-1 accompanied by a cyclic oscillation with amplitude and period of 0.0069 d and 10.65 yr *** most likely explanation for the long-term decrease is angular momentum *** existence of an additional star is the most plausible explanation for the periodic variation.

关键词： stars:binaries:close stars:binaries:eclipsing stars:individual (FP Lyn, FV CVn and V354 UMa)

Reconstructing gene regulatory networks in single-cell transcriptomic data analysis

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Zoological Research 2020年第6期41卷 599-604页

作者： Hao Dai qi-qi Jin Lin Li Luo-Nan Chen Key Laboratory of Systems Biology Shanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai 200031China Institute of Brain-Intelligence Technology Zhangjiang LaboratoryShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Key Laboratory of Systems Biology Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesChinese Academy of SciencesHangzhouZhejiang 310024China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China

Gene regulatory networks play pivotal roles in our understanding of biological processes/mechanisms at the molecular *** studies have developed sample-specific or cell-type-specific gene regulatory networks from single-cell transcriptomic data based on a large amount of cell ***,we review the state-of-the-art computational algorithms and describe various applications of gene regulatory networks in biological studies.

关键词： Gene regulatory network Single-cell RNA sequencing Computational algorithm Sample-specificnetwork Cell-type-specific network Cell-specific network

The risks of sulfur addition on cadmium accumulation in paddy rice under different water-management conditions

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Journal of Environmental Sciences 2022年第8期34卷 101-111页

作者： Zhe Liu qi-qi Wang Si-yu Huang Ling-xuan Kong Zhong Zhuang qi Wang Hua-fen Li Ya-nan Wan Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation Key Laboratory of Plant-Soil Interactions of the Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Recently, the application of sulfur(S) has been recommended to control the accumulation of cadmium(Cd) in rice in contaminated paddy soil. However, the effects of exogenous S on Cd transfer in paddy rice systems under different water-management practices have not been systematically investigated. Pot experiments were performed to monitor the composition of soil pore water and the Cd accumulation in iron plaque and rice tissue were compared under different S(0 and 200 mg/kg Na_(2)SO_(4)) and water(continuous and discontinuous flooding) treatments. Sulfur application significantly increased Cd concentrations in soil pore water under discontinuous flooding conditions, but slightly reduced them under continuous flooding. Moreover, the oxidation/reduction potential(Eh) was the most critical factor that affected the Cd levels. When the Eh exceeded-42.5 mV, S became the second critical factor, and excessive S application promoted Cd dissolution. In addition, S addition elevated the Cd levels in iron plaque and reduced the Cd transfer from the iron plaque to rice roots. In rice, S addition inhibited Cd transfer from the rice roots to the straw;thus, more Cd was stored in the rice roots. Nevertheless, additional S application increased the Cd content in the rice grains by 72% under discontinuous flooding, although this effect was mitigated by continued flooding. Under simulated practical water management conditions, S addition increased the risk of Cd contamination in rice, suggesting that S application should be reconsidered as a paddy fertilization strategy.

关键词： Rice Cadmium Sulfur Water management Iron plaque Accumulation