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Molecular Dynamics Investigation of Differences in Melting Behaviors of Cu57 and Cu58 Clusters

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Chinese Journal of Chemical Physics 2009年第1期22卷 69-74页

作者： Lin Zhang hai-xia Sun Institute of Materials Physics and Chemistry College of Science Northeastern University Shenyang 110004 China

Within the framework of the embedded-atom method, we performed molecular-dynamics calculations to investigate the structural transformation during melting of two copper clus- ters containing 57 and 58 atoms. The simulation results reveal how their different structural changes can strongly influence internal energy and radial distribution functions. The local structural patterns of different regions during the temperature increase, determined by atom density profiles, are identified for the melting of each cluster. The simulations show sensi- tivities of the structural changes for these two small size clusters with different structures.

关键词： Molecular dynamics Cluster Surface Melting

Thermal decomposition effect of MgCo_(2)O_(4)nanosheets on ammonium perchlorate-based energetic molecular perovskites

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Defence Technology（防务技术） 2023年第2期20卷 111-119页

作者： Er-hai An xiao-xia Li hai-xia Zhao Ying-xin Tan Xiong Cao Peng Deng School of Environment and Safety Engineering North University of ChinaTaiyuan030051ShanxiPeople's Republic of China School of Engineering for Safety and Emergency Management Taiyuan University of Science and TechnologyTaiyuan030024China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081People's Republic of China

Energetic molecular perovskites have attracted widespread attention in the fields of energy materials due to their high detonation *** this work,we reported the effect of MgCo_(2)O_(4) nanosheets on the thermal decomposition of ammonium perchlorate(NH_(4)ClO_(4),AP)-based energetic molecular perovskites(AP-based energetic molecular perovskites).The morphology and structure of the MgCo_(2)O_(4) nanosheets were *** their catalytic effect on the thermal decomposition of AP-based energetic molecular perovskites(H_2pz)[NH_(4)(ClO_(4))_(3)](PAP-4),(H_2dabco)[NH_(4)(ClO_(4))_(3)](DAP-4),(H_2mpz)[NH_(4)(ClO_(4))_(3)](PAP-M_(4)),and (H_2hpz)[NH_(4)(ClO_(4))_(3)](PAP-H_(4)) was *** results showed that MgCo_(2)O_(4) nanosheets had excellent intrinsically catalytic performance towards enhancing the thermal decomposition of AP-based energetic molecular *** adding MgCo_(2)O_(4) nanosheets,the thermal decomposition peak temperatures of PAP-4,DAP-4,PAP-M_(4),and PAP-H_(4) had been reduced by35.7℃,48.4℃,37.9℃,and 43.6℃,*** the activation energy(Ea)of the thermal decomposition of AP-based energetic molecular perovskites had been reduced,the Eaof PAP-H_(4) decreased by 46.4 kJ/mol at most among *** catalytic mechanism of MgCo_(2)O_(4) nanosheets for AP-based energetic molecular perovskites is *** work provides a reference for the future application of AP-based energetic molecular perovskites.

关键词： AP-based energetic molecular perovskites MgCo_(2)O_(4)nanosheets Thermal decomposition Catalytic performance

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溢流式面板堆石坝坝身变形特性敏感性研究

水利科技与经济 2020年第8期26卷 27-32页

作者：耿旭李怀斌刘辛党海霞李祥渠继显任国兵吴俊贵州新中水工程有限公司贵阳550000 六枝特区水务局贵州六盘水553400 贵州省建材产品质量监督检验院贵阳550000 安顺市水利水电勘测设计院贵州安顺561000

为探索锚固梁宽度、锚固梁高度、锚拉筋长度、锚固板长度、泄洪量以及堰顶插筋长度等因素对溢流面坝身变形的影响,采用正交设计方法,依托在建工程松树林水库,采用非线性弹性模型(邓肯E-B模型)确定溢流面坝身变形,通过极差分析,确定各因... 详细信息

为探索锚固梁宽度、锚固梁高度、锚拉筋长度、锚固板长度、泄洪量以及堰顶插筋长度等因素对溢流面坝身变形的影响,采用正交设计方法,依托在建工程松树林水库,采用非线性弹性模型(邓肯E-B模型)确定溢流面坝身变形,通过极差分析,确定各因素对溢流式面板堆石坝溢流面坝身变形的敏感性。结果表明,堰顶插筋长度对变形量的影响最大;锚固板长度对变形量的影响最小。

关键词：溢流式面板堆石坝变形特性正交设计邓肯E-B模型

Optimal Placement of Active Members in Truss Adaptive Structures

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Chinese Journal of Mechanical Engineering 2010年第2期23卷 233-241页

作者： ZHANG Lianwen xia Renwei HUANG hai School of Mechanical Engineering Tianjin University of Commerce Tianjin 300134 China School of Astronautics Beijing University of Aeronautics ＆ Astronautics Beijing 100083 China

The mathematical model of optimal placement of active members in truss adaptive structures is essentially a nonlinear multi-objective optimization problem with mixed variables. It is usually much difficult and costly to be solved. In this paper, the optimal location of active members is treated in terms of （0, 1） discrete variables. Structural member sizes, control gains, and （0, 1） placement variables are treated simultaneously as design variables. Then, a succinct and reasonable compromise scalar model, which is transformed from original multi-objective optimization, is established, in which the （0, 1） discrete variables are converted into an equality constraint. Secondly, by penalty function approach, the subsequent scalar mixed variable compromise model can be formulated equivalently as a sequence of continuous variable problems. Thirdly, for each continuous problem in the sequence, by choosing intermediate design variables and temporary critical constraints, the approximation concept is carried out to generate a sequence of explicit approximate problems which enhance the quality of the approximate design problems. Considering the proposed method, a FORTRAN program OPAMTAS2.0 for optimal placement of active members in truss adaptive structures is developed, which is used by the constrained variable metric method with the watchdog technique （CVMW method）. Finally, a typical 18 bar truss adaptive structure as test numerical examples is presented to illustrate that the design methodology set forth is simple, feasible, efficient and stable. The established scalar mixed variable compromise model that can avoid the ill-conditioned possibility caused by the different orders of magnitude of various objective functions in optimization process, therefore, it enables the optimization algorithm to have a good stability. On the other hand, the proposed novel optimization technique can make both discrete and continuous variables be optimized simultaneously.

关键词： truss adaptive structure optimal placement active member multi-objective optimization mixed variables penalty function approach

Dynamic Response of Truss Adaptive Structures

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 849-855页

It is pointed out that the damping matrix deduced by active members in the finite element vibration equation of a truss adaptive structure generally can not be decoupled, which leads to the difficulty in the process of modal analysis by classical superposition method. This paper focuses on the computational method of the dynamic response for truss adaptive structures. Firstly, a new technique of state vector approach is applied to study the dynamic response of truss adaptive structures. It can make the coeffic lent matrix of first derivative of state vector a symmetric positive definite matrix, and particularly a diagonal matrix provided that mass matrix is derived by lumped method, so the coefficient matrix of the first derivative of state vector can be exactly decomposed by CHOLESKY method. In this case, the proposed technique not only improves the calculation accuracy, but also saves the computing time. Based on the procedure mentioned above, the mathematical formulation for the system response of truss adaptive structures is systematically derived in theory. Thirdly, by using FORTRAN language, a program system for computing dynamic response of truss adaptive structures is developed. Fourthly, a typical 18 bar space truss adaptive structure has been chosen as test numerical examples to show the feasibility and effectiveness of the proposed method. Finally, some good suggestions, such as how to choose complex mode shapes practically in determining the dynamic response are also given. The new approach can be extended to calculate the dynamic response of general adaptive structures.

关键词： truss adaptive structure dynamic response active member complex modal analysis state vector approach

Nuclei-rich galvanizing strategy for suppressing zinc dendrite growth

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Rare Metals 2024年第8期43卷 4016-4018页

作者： hai-xia Wu Kai-Lu Guo College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934China

The uncontrolled growth of zinc dendrites on zinc anode hinders the application of zinc ion *** solve this problem,Lu's group proposed a nuclei-rich galvanizing strategy for suppressing the zinc dendrite *** allows the nuclei-rich zinc electrode to cycle steadily for1200 h and have a high Coulombic efficiency of 99.7%at15 mA·cm^(-2)with a deposited amount of 10 mAh·cm^(-2).Moreover,the Zn-MnO_(2) battery with a low N/P ratio of 1.9exhibited sustained cycling life.

关键词： cycling sustained battery

Zeolite polymer membrane as protective interface for Mg battery

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Rare Metals 2024年第9期43卷 4636-4638页

作者： hai-xia Wu Kai-Lu Guo College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934China

Excessive electrolyte decomposition seriously determines the performance of high-voltage Mg batteries. In Nazar's work, the strategy using a zeolite polymer membrane as a protective interface was proposed to restrain the electrolyte decomposition. This strategy could boost Mg plating/stripping performance up to 6000 h in zeolite/Mg|zeolite/Mg symmetric cells and 91%capacity retention in zeolite/Mg||Mo_(3)S_(4)battery after 200 *** storage devices have been intensively explored because of their important roles in our daily lives [1D3].

关键词： zeolite interface electrolyte

Prognosis of HER2 over-expressing gastric cancer patients with liver metastasis

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World Journal of Gastroenterology 2012年第19期18卷 2402-2407页

作者： hai-Zhen dang Yang Yu Shun-Chang Jiao Department of Medical Oncology GeneralHospital of the People＇s Liberation Army Beijing 100853 Chi}aa Department of Traditional Chinese Medicine FirstHospital Affiliated to the General Hospital of the People＇s Libera-tion Army Beijing 100048 China Yang Yu Department of Traditional Chinese Medicine FirstHospital Affiliated to the General Hospital of the People＇s Libera-tion Army Beijing 100048 China Department of Medical Oncology GeneralHospital of the People＇s Liberation Army Beijing 100853 China

AIM:To study the risk factors for liver metastasis and the prognosis in patients with human epidermal growth factor receptor 2(HER2) over-expressing gastric cancer(GC).METHODS:A total of 84 GC patients recruited from the General Hospital of the People's Liberation Army(PLA) between 2003 and 2010 were randomly enrolled in this ***2 expression was detected by immunohistochemistry in 84 GC patients with liver *** study group consisted of 66 men and 18 women,with an average age of 54 years(range:19-74 years).Liver metastasis was diagnosed by magnetic resonance imaging or computed *** were followed-up and predictive factors of liver metastasis were ***:The median follow-up period was 47 mo(range:6-85 mo).The characteristics of 35(25.7%) patients with HER2 over-expression of liver metastatic GC are ***2 over-expression was detected in 23 out of 49(46.9%) patients with intestinal GC,and 9 out of 35(25.7%) patients with diffuse GC.29 out of 59(49.2%) patients aged < 60 years were HER2positive,while 8 out of 25(32%) patients aged ≥ 60 were HER2-positive;a significant difference(P < 0.05).Univariate analysis(log-rank test) showed that HER2 over-expression,sex,Lauren classification,differentiation and disease-free interval were correlated with poor survival(P < 0.05).Survival analysis with a survival curve showed that HER2 over-expression was significantly relevant,with a reduced survival time in GC patients with liver metastases(P < 0.01).2-year survival was not associated with the patient's age.A diseasefree survival longer than 12 mo has a significant association with extended overall survival(OS) in GC patients with liver *** median survival time after the diagnosis of liver metastases was 18 mo [95% confidence interval(CI):9.07-26.94] among HER2 positive GC patients with liver *** comparison,for 49(69.4%) out of 84 HER2 negative patients with liver metastatic GC,the median survival time was 47 m

关键词： Human epidermal growth factor receptor 2 Overexpression Gastric cancer Liver metastasis Over-all survival Prognosis

Fault Information Recognition for On-board Equipment of High-speed Railway Based on Multi-neural Network Collaboration

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International Journal of Automation and computing 2021年第6期18卷 935-946页

作者： Lu-Jie Zhou Jian-Wu dang Zhen-hai Zhang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Gansu Provincial Engineering Research Center for Artificial Intelligence and Graphic&Image Processing Lanzhou 730070China

It is of great significance to guarantee the efficient statistics of high-speed railway on-board equipment fault information,which also improves the efficiency of fault analysis. Considering this background, this paper presents an empirical exploration of named entity recognition(NER) of on-board equipment fault information. Based on the historical fault records of on-board equipment, a fault information recognition model based on multi-neural network collaboration is proposed. First, considering Chinese recorded data characteristics, a method of constructing semantic features and additional features based on character granularity is proposed. Then, the two feature representations are concatenated and passed into the gated convolutional layer to extract the dependencies from multiple different subspaces and adjacent characters in parallel. Next, the local features are transmitted to the bidirectional long short-term memory(BiLSTM) to learn long-term dependency information. On top of BiLSTM, the sequential conditional random field(CRF) is used to jointly decode the optimized tag sequence of the whole sentence. The model is tested and compared with other representative baseline models. The results show that the proposed model not only considers the language characteristics of on-board fault records, but also has obvious advantages on the performance of fault information recognition.

关键词： Train control system Chinese named entity recognition(NER) character feature gating mechanism bidirectional long short-term memory(BiLSTM)

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