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One-pot synthesis of crystalline SnO_2 nanoparticles and their low-temperature ethanol sensing characteristics

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1601-1605页

作者： CHEN YuJin1,2,3,ZHU ChunLing4,WANG LiJiao3 & WANG TaiHong2 1 School of Materials science and engineering,Beijing Institute of Technology,Beijing 100081,china 2 Micro-Nano Technologies Research Center,Hunan university,Changsha 410082,china 3 college of science,harbin engineering university,harbin 150001,china 4 college of Material science and Chemical engineering,harbin engineering university,harbin 150001,china School of Materials science and engineering Beijing Institute of Technology Beijing 100081 China Micro-Nano Technologies Research Center Hunan University Changsha 410082 China college of science Harbin Engineering University Harbin 150001 China college of Material science and Chemical engineering Harbin Engineering University Harbin 150001 China

Crystalline SnO2 nanoparticles(NPs) with a diameter less than 6 nm are synthesized using potassium stannate trihydrate as the precursor in a basic *** synthesized NPs can detect ethanol at a ppm level even at 100℃.Furthermore,the NPs have good selectivity to *** excellent ethanol sensing performances are attributed to the small size effect according to the space-charge model.

关键词： SnO2 nanoparticles sensing characteristics

Dynamic real-time simulation research of once-through steam generator with concentric annuli tube

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Dynamic real-time simulation research of once-through steam ...

第三届21世纪和谐核电系统国际会议（ISSNP2010）

作者： ZHU Jing-yan1, ZHANG Zhi-jian 2, and GUO Yun 3 1. college of Nuclear science and technology, harbin engineering university, harbin 150001, china 2. college of Nuclear science and technology, harbin engineering university, harbin 150001, china (zhangzhijian@***) 3. college of Nuclear science and technology, harbin engineering university, harbin 150001, china

Based on the conservation equations of mass, energy, and momentum, the mathematical model of once-through steam generator (OTSG) with concentric annuli tube is developed by lumped parameters with moving boundary. The heat transfer section of OTSG is divided into three regions: subcooled, nucleate boiling and superheat regions. The stable and dynamic simulations are analyzed by Gear method. The results show that the developed model and code are accurate, effective and can be used to simulate the steam generator dynamics in real-time.

关键词： once-through steam generator dynamic characteristic moving boundary

来源： cnki会议评论

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一种服务多维信任属性模型的研究

计算机工程与应用 2009年第30期45卷 161-164页

作者：刘世勇罗美淑杜百玲黑龙江幼儿师范高等专科学校黑龙江牡丹江157011 牡丹江师范学院计算机科学与技术系黑龙江牡丹江157012 哈尔滨工程大学计算机科学与技术学院哈尔滨150001

随着Web服务研究的不断深入,从服务角色的角度出发考虑服务结构已经成为研究的热点问题。主要从服务的使用者、提供者和服务本身三个方面考虑,提出一个服务信任管理模型,通过使用者对服务信任属性的反馈信息修正提供者发布的服务主观信... 详细信息

随着Web服务研究的不断深入,从服务角色的角度出发考虑服务结构已经成为研究的热点问题。主要从服务的使用者、提供者和服务本身三个方面考虑,提出一个服务信任管理模型,通过使用者对服务信任属性的反馈信息修正提供者发布的服务主观信任信息,通过服务组装过程中获得的信任信息修正提供者提供的服务客观信任信息,从而为用户提供更加准确的基于信任的服务推荐。

关键词： Web服务多维信任属性

NUMERICAL SIMULATION OF SLOSHING IN RECTANGULAR TANK WITH VOF BASED ON UNSTRUCTURED GRIDS

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Journal of Hydrodynamics 2010年第6期22卷 856-864页

作者： MING Ping-jian DUAN Wen-yang college of Power and Energy engineering Harbin Engineering University Harbin 150001 China college of Shipbuilding engineering Harbin Engineering University Harbin 150001 China

A new method for sloshing simulation in a sway tank is present, in which the two phase interface is treated as a physical discontinuity, which can be captured by a well-designed high order scheme. Based on Normalized Variable Diagram （NVD）, a high order discretization scheme with unstructured grids is realized, together with a numerical method for free surface flow with a fixed grid. This method is implemented in an in-house code General Transport Equation Analyzer （ GTEA ） which is an unstructured grids finite volume solver. The present method is first validated by available analytical solutions. A simulation for a 2-D rectangular tank at different excitation frequencies of the sway is carried out. A comparison with experimental data in literature and results obtained by commercial software CFX shows that the sloshing load on the monitor points agrees well with the experimental data, with the same grids, and the present method gives better results on the secondary peak. It is shown that the present method can simulate the free surface overturning and breakup phenomena.

关键词： sloshing numerical simulation unstructured grid Volume Of Fluid (VOF)

Performance tests of multi-metal zincate solutions with zinc sulfate and zinc oxide

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Rare Metals 2007年第S1期26卷 99-104页

作者： HUANG Xiaomei,and ZHANG Milin college of Materials science and Chemical engineering,harbin engineering university,harbin 150001,china harbin Engn Univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron *** was applied to analyze the components of zinc alloy layer and the interface of high-Si aluminum alloy substrate-zinc ***,the surface morphology of the zincated aluminum alloy after immersing in 3.5% NaCl solution for 7 d,is observed and the corrosion rate was ***,tension test is conducted to quantify the adhesion between high-Si aluminum cast substrate and the *** results show that,the zinc oxide contained zincating solution with sodium potassium tartrate and sodium citrate is a better one in multi-metal zincating *** zinc alloy layer from this one gets stable performance,perfect adhesion with deposit,and good corrosion resistance.

关键词： Al-Si alloy multi-metal zincating solution adhesion

New method for passive radar seeker to antagonize non-coherent radar decoy

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Journal of Systems engineering and Electronics 2010年第3期21卷 397-403页

作者： Weijian Si,Xicai Si,and Zhiyu Qu college of Information and Communication engineering,harbin engineering university,harbin 150001,P.R.china college of Information and Communication engineering Harbin Engineering UniversityHarbin 150001P.R.China

Using super resolution direction of arrival（DOA） estimation algorithm to reduce the resolution angle is an effective method for passive radar seeker（PRS） to antagonize non-coherent radar *** the power and correlation property between radar and non-coherent decoy,an improved subspace DOA estimation method based on traditional subspace algorithm is *** this new method uses the invariance property of noise subspace,compared with traditional MUSIC algorithm,it shows not only better resolution in condition of closely spaced sources,but also superior performance in case of different power or partially correlated *** this new method,PRS can distinguish radar and non-coherent decoy with good *** the simulation result and the experimental data confirm the performance of the method.

关键词： radar countermeasures passive radar seeker(PRS) non-coherent decoy direction of arrival(DOA) estimation.

On Form Invariance,Lie Symmetry and Three Kinds of Conserved Quantities of Generalized Lagrange's Equations

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Communications in Theoretical Physics 2007年第7期48卷 37-42页

作者： ZHAO Shu-Hong LIANG Li-Fuoi School of Civil engineering,harbin engineering university,harbin 150001,china2 engineering college,Northeast Agricultural university,harbin 150030,china School of Civil engineering Harbin Engineering University engineering college Northeast Agricultural University

In this paper,the form invariance and the Lie symmetry of Lagrange's equations for nonconservativesystem in generalized classical mechanics under the infinitesimal transformations of group are studied,and the Noether'sconserved quantity,the new form conserved quantity,and the Hojman's conserved quantity of system are derived ***,an example is given to illustrate the application of the result.

关键词： form invariance Lie symmetry conserved quantity generalized classical mechanics Lagrange’s equation

A circular zone partition method for identifying Duffing oscillator state transition and its application to BPSK signal demodulation

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science china(Information sciences) 2011年第6期54卷 1274-1282页

作者： FU YongQing 1 , WU DongMei 1 , ZHANG Lin 2 & LI XingYuan 1 1 college of Information and Communication engineering, harbin engineering university, harbin 150001, china 2 college of Underwater Acoustic engineering, harbin engineering university, harbin 150001, china 1. college of Information and Communication engineering Harbin Engineering University Harbin 150001 China2. College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

When a Duffing oscillator is applied to signal detection, identifying its state transition is indispensable. Due to lack of an effective method for automatically distinguishing the state transition, phase analysis is extensively used. However, it needs ocular estimation to identify phase pattern corresponding to transition of Duffing oscillator. Hence it is not fit for communication signal demodulation. To solve the problem, this paper proposes a method, called circular zone partition (CZP), for partitioning trajectory on the phase plane of Duffing oscillator. First, a computing model for Duffing oscillator is described. Then, the fundamental principle and algorithm for the CZP method are discussed. Meanwhile the equation of a circular zone divider and its realization are presented. Thus, by way of the divider, the two-dimensional phase trajectory pattern of Duffing oscillator driven by an external signal can be transformed into the one-dimensional time signal, whose envelop after being filtered is able to indicate the state transition, i.e. the presence or the absence of external signal. Finally, to verify the effect of the CZP method on binary phase shifted keying (BPSK) signal demodulation, two examples are presented and simulation results show that this CZP method is accurate and valid for BPSK signal demodulation.

关键词： chaos nonlinear oscillators signal detection digital communication receivers

STRESS CONCENTRATIONS IN CYLINDRICAL SHELLS WITH LARGE OPENINGS

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Acta Mechanica Solida Sinica 1997年第3期10卷 220-234页

作者： Liu Diankui Song Tianshu, harbin engineering university, harbin 150001, china harbin ENGN LAB HARBIN 150001PEOPLES R CHINA

Based on Donnell's shallow shell equation, a new method is given in this paper to analyze theoretical solutions of stress concentrations about cylindrical shells with large openings. With the method of complex variable function, a series' of conformal mapping functions are obtained from different cutouts' boundary curves in the developed plane of a cylindrical shell to the unit circle. And, the general expressions for the equations of a cylindrical shell, including the solutions of stress concentrations meeting the boundary conditions of the large openings' edges, are given in the mapping plane. Furthermore, by applying the orthogonal function expansion technique, the problem can be summarized into the solution of infinite algebraic equation series. Finally, numerical results are obtained for stress concentration factors at the cutout's edge with various opening's ratios and different loading conditions. This new method, at the same time, gives a possibility to the research of cylindrical shells with large non-circular openings or with nozzles.

关键词： cylindrical shell with large opening theoretical solution for single circular cutout conformal mapping and complex variable method