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CCS Chemistry 2024年第4期6卷 964-975页

作者： xu Han Tian-Yu Sun Yi Isaac Yang Jun Zhang Jing q.u Zhaoping Xiong Nan q.ao Yun-Dong Wu Yi q.n Gao Institute of Theoretical and Computational Chemistry College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 Shenzhen Bay Laboratory Shenzhen 518132 Changping Laboratory Beijing 102200 Laboratory of Health Intelligence Huawei Cloud Computing Technologies Co.Ltd.Guizhou 550025

The bond breaking and forming in chemical reactions is a typical rare event,which is one of the difficult problems in molecular dynamics *** enhanced sampling methods have been developed to extend the time scale covered by molecular ***,the difficulties of obtaining appropriate collective variables from complicated reaction pathways and a controlled sampling over the desired phase space remain as ***,we use MetaITS,which combines metadynamics and integrated tempered sampling,to increase the sampling efficiency for chemical *** with collective variables obtained by harmonic linear discriminant analysis can efficiently decrease the main energy barrier of chemical ***,integrated tempered sampling can enhance the exploration of other degrees of *** this study,we applied the MetaITS method to two transition-metal-catalyzed organic reactions with complicated reaction *** simulated here a zirconocene-catalyzed propylene polymerization to investigate the regioselectivity and temperature *** also studied a Sharpless epoxidation reaction,for which both chiral products are observed through simulation.

关键词： molecular dynamics enhanced sampling metadynamics integrated tempering sampling propylene polymerization Sharpless epoxidation

Association of Human Whole-blood NAD+Levels with Nabothian Cyst

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Biomedical and Environmental Sciences 2024年第5期37卷 471-478页

作者： xu Ling WANG Yue xuan WANG Wei FAN xue CHEN xue Yu ZHOU Tian Yun LIU Yu He YU Ye YANG Fan JU Zhen Yu ZHOU Yong WANG Deng Liang Clinical Research Institute Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China NHC Key Lab of Reproduction Regulation Shanghai Engineering Research Center of Reproductive Health Drugs and DevicesShanghai Institute for Biomedical and Pharmaceutical TechnologiesShanghai 200237China Department of Applied Statistics Johannes Kepler University LinzLinz 4040Austria Hematology Center Beijing Key Laboratory of Pediatric Hematology OncologyNational Key Discipline of Pediatrics(Capital Medical University)Key Laboratory of Major Diseases in ChildrenMinistry of EducationBeijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China Department of Biostatistics School of Public HealthCheeloo College of MedicineShandong UniversityJinan 250012ShandongChina Clinical Medicine School of Basic MedicineShanghai Medical College Fudan UniversityShanghai 200032China Department of Biochemistry and Molecular Biology Hengyang Medical SchoolUniversity of South ChinaHengyang 421001HunanChina Administrative Office Total Quality Management OfficeTotal Quality Management InstituteShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China The First Affiliated Hospital of Jinan University Institute of Aging and Regenerative MedicineJinan UniversityJinan 510632GuangzhouChina Department of Scientific Research The First Affiliated Hospital of Huzhou UniversityHuzhou 313000ZhejiangChina Department of Neurosurgery Neurosurgery Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhou 350005FujianChina Department of Neurosurgery Binhai Branch of National Regional Medical CenterThe First Affiliated HospitalFujian Medical UniversityFuzhou 350209FujianChina Fujian Provincial Institutes of Brain Disorders and Brain Sciences The First Affiliated HospitalFujian Medical UniversityFuzhou 350005FujianChina Fujian Provincial Clinical Research Center for Neurological

Objective Little is known about the association between whole-blood nicotinamide adenine dinucleotide(NAD^(+))levels and nabothian *** study aimed to assess the association between NAD^(+)levels and nabothian cysts in healthy Chinese *** Multivariate logistic regression analysis was performed to analyze the association between NAD^(+)levels and nabothian *** The mean age was 43.0±11.5 years,and the mean level of NAD^(+)was 31.3±5.3μmol/*** cysts occurred in 184(27.7%)participants,with single and multiple cysts in 100(15.0%)and84(12.6%)participants,*** total nabothian cyst prevalence gradually decreased from37.4%to 21.6%from q. to q. of NAD^(+)and the prevalence of single and multiple nabothian cysts also decreased across the NAD^(+)*** compared with the highest NAD^(+)q.artile(≥34.4μmol/L),the adjusted odds ratios with 95%confidence interval of the NAD^(+)q. was 1.89(1.14–3.14)for total nabothian *** risk of total and single nabothian cysts linearly decreased with increasing NAD^(+)levels,while the risk of multiple nabothian cysts decreased more rapidly at NAD^(+)levels of 28.0 to35.0μmol/***:Low NAD^(+)levels were associated with an increased risk of total and multiple nabothian cysts.

关键词： Nicotinamide adenine dinucleotide Nabothian cyst Female Risk factor

STUDY ON THE VARIATION MECHANISM OF CARBON CONTENT OF LIq.ID IRON IN MELTING GASIFIER

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Acta Metallurgica Sinica(English Letters) 2003年第2期16卷 132-138页

作者： q.Lu L.F Sun Y.xu q.F.Chan Hebei University of Technology Tangshan 063009ChinaHebei University of TechnologyTangshan 063009ChinaHebei University of TechnologyTangshan 063009ChinaHebei Institute of Vocation and TechnologvShiiiazhuang 050031China

This paper studied the changing principles of carbon content in direct reduction iron (DRI) and liq.id iron in the COREX melting gasifier. Under the normal working conditions of experimental eq.ipment, liq.id nitrogen was poured into the melting gasifier from its tuyere to cool down q.ickly. And then seven cross sections were made to study the carburization reaction and its characteristics of the solid iron and the liq.id iron, and also the reaction of carbon between the slag and the metal. According to the results, the influences of the thickness of the semi-coke layer and the temperature on the carbon content of liq.id iron in the COREX melting gasifier were confirmed.

关键词： melting gasifier direct reduction iron (DRI) liq.id iron carbon content

Clinicopathologic study of primary intestinal B cell malignantlymphoma

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World Journal of Gastroenterology 1999年第6期5卷 538-540页

作者： Zhou q.xu TR Fan q. Zhen ZX Nanjing Med Univ Affiliated Hosp 1 Dept Pathol Nanjing 210029 Jiangsu Prov Peoples R China

INTRODUCTIONPrimary intestinal B cell lymphoma is one of the most common extra-nodal lymphomas, which includes two types: intestinal mucosa-associated lymphoid tissue lymphoma (IMALToma) and lymphomatous polyposis (LP). Both have characteristic pathologic features, immunophen-otypes and biological behaviors. In this article, twenty-five cases were retrospectively analyzed with regard to criteria of diagnosis and clinicopathologic characteristics.

关键词： lymphoma/pathology intestinal neoplasms/pathology intestinal neoplasms/diagnosis

Mechanical properties of cocoons constructed consecutively by a single silkworm caterpillar,Bombyx mori

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Acta Mechanica Sinica 2008年第2期24卷 151-160页

作者： S.q.Huang H.P.Zhao X.q.Feng W.Cui Z.Lin M.q.xu Department of Engineering Mechanics FML Tsinghua University Beijing 100084 China Department of Sericulture Shandong Agriculture University Tai'an 271018 China Department of Landscape Architecture Human Environment-Biological Polytechnic College. Hengyang 421005 China

Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons by taking it out from the cocoon being constructed. The mechanical properties of these cocoons were studied by static tensile tests and dynamic mechanical thermal analysis. Though external disturbances may cause the decrease in the total weight of silk spun by the silkworm, a gradual enhancement was interestingly found in the mechanical properties of these thin cocoons. Scanning electron microscopy observations of the fractured specimens of the cocoons showed that there exist several different energy dissipation mechanisms occurred simultaneously at macro-, meso-, and micro-scales, yielding a superior capacity of cocoons to adsorb the energy of possible attacks from the outside and to protect efficiently its pupa against damage. Through evolution of millions of years, therefore, the silkworm Bombyx mori seems to have gained the ability to adapt external disturbances and to redesign a new cocoon with optimized protective function when its first cocoon has been damaged for some reasons.

关键词： Silk Silkworm cocoon Mechanical property Biomimetics

Constructing an Energy Function for Power Systems with DFIGWT Generation Based on a Synchronous-generator-mimicking Model

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CSEE Journal of Power and Energy Systems 2022年第1期8卷 64-75页

作者： Yang Liu Chenying xu Zehui Lin Kaishun Xiahou q.H.Wu the School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

In this paper we construct an energy function for multi-machine power systems with doubly-fed induction generator-based wind turbine(DFIGWT)according to a synchronous-generator-mimicking(SGM)model of the *** SGM model is proposed to approximate the dynamics of a *** to the modelling of a synchronous generator(SG),the internal dynamics of a DFIGWT are also described with differential eq.ations of newly constructed virtual rotor angle and internal electromotive force(EMF)in the SGM ***,the power flow of a DFIGWT is expressed by nonlinear functions of its virtual rotor angle and internal *** SGM model bridges the gap between the irregular and complex modelling of DFIGWTs and the well-developed energy function construction techniq.es for SG *** on the SGM model,a numerical energy function is constructed for power systems with DFIGWT *** theoretical analysis and numerical studies were undertaken to validate that the proposed energy function satisfies the necessary conditions for an energy function of a power system.

关键词： DFIGWT energy function multi-machine power systems synchronous-generator-mimicking model

Conformal deformation of a close Riemannian submanifold to minimal submanifold

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Chinese Science Bulletin 1998年第6期43卷 527-527页

作者： xu, S. Xia, q. Univ Sci & Technol China Dept Math Hefei 230026 Peoples R China

Presents proof on the conformal deformation of a close Riemannian submanifold to minimal submanifold. Potential mean curvature vector field of Riemannian submanifold; Deformation of the metric of a minimal submanifold.

关键词： Conformal deformation of a close Riemannian submanifold to minimal submanifold

Multi-scale simulation of columnar-to-eq.iaxed transition during laser selective melting of rare earth magnesium alloy

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Journal of Materials Science & Technology 2022年第24期119卷 11-24页

作者： W.L.Wang W.q.Liu X.Yang R.R.xu q.Y.Dai School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

A model of coupling macro finite volume method(FVM) and cellular automata(CA) is proposed in this paper to explore the columnar-to-eq.iaxed transition(CET) during selective laser melting(SLM) of rare earth magnesium *** into account the impact of recoil pressure and Marangoni convection on the molten pool temperature field,the grain structure is *** suggested by the simulation results,with the undissolved Zr serving as heterogeneous nucleation sites,the liq.id undercooled layer under the combined action of forced cooling,the temperature gradient and the liq.id solute concentration gradient leads to *** considering the dissolution of Zr in magnesium matrix,the results demonstrate that the dissolution of element Zr is effective in significantly inhibiting the growth of columnar crystals and ensuring the sufficient constitutional supercooling(CS) req.ired for *** addition,to raise the preheating temperature contributes to enhancing the outcome of nucleation and incresing the grain *** the interdependence model(IM),with the cooling rate gradually increasing in the SLM process of magnesium alloy,the nucleation-free zone(NFZ) reduces by decreasing the solute diffusion layer in the front of the solid/liq.id(SL) interface and the temperature *** reduction in temperature gradient can promote undercooling for nucleation and facilitate the development of eq.iaxed *** simulation results are q.alitatively verified as highly consistent through experimentation.

关键词： Multi-scale simulation Columnar-to-eq.iaxed transition Selective laser melting Rare earth magnesium alloy Constitutional supercooling

磁链分区的磁场增强型永磁电机全速域模型预测直接转矩控制

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中国电机工程学报 2024年第11期44卷 4480-4489,I0026页

作者：朱孝勇薛高鸣徐磊江苏大学电气信息工程学院江苏省镇江市212013

磁场增强型内置式永磁(flux intensifying interior permanent magnet,FI-IPM)电机的反凸极(L_(q. 详细信息

磁场增强型内置式永磁(flux intensifying interior permanent magnet,FI-IPM)电机的反凸极(L_(q.

关键词：磁场增强型内置式永磁电机反凸极模型预测直接转矩控制磁链分区全速域控制

NEUROCOMPUTING THEORY AND NUMERICAL SIMULATION ON ELASTICITY

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Acta Mechanica Solida Sinica 1999年第3期12卷 269-278页

作者： Sun, DH Sun, XF Hi, q.xu, H Xiamen Univ Dept Electromech Engn Xiamen 361005 Peoples R China Sw Jiaotong Univ Dept Appl Mech & Engn Chengdu 610031 Peoples R China NE Univ Technol Inst Engn Mech Shenyang 110006 Peoples R China

A new finite element analysis principle based on neural networks is proposed. It can realize the finite element analysis in real time. The neural computation of a simple structure was simulated on digital computer, the effect of input parameters on convergent speed and precision was analyzed. Before solving a certain FE problem, the linking weight matrix of the neural net, i.e., the global stiffness matrix of the structure analyzed, must be defined. In this paper, a method which uses the BP net to compute the element stiffness matrix in real time is proposed.

关键词： neural networks elasticity finite element real-time computation