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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of {1. and {2. Beijing,Beijing,china

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of {2.—{2.0μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

Suitability Evaluation on the Information Service System of "Agricultural science and {1. 1.0" in Sichuan Province, china

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Asian Agricultural Research 2010年第9期2卷 17-20,24页

作者： HU Yu-fu1.2.DENG Liang-ji1.2.1. College of Economics and Management,Sichuan Agricultural university, Ya′an 62.01., {1. 2. College of Resources and Environment, Sichuan Agricultural university, Ya′an 62.01., {1.

Method of fuzzy comprehensive evaluation is used to carry out suitability evaluation on the information service system of "Agricultural science and {1. 1.0" in Sichuan Province, china. Analytic hierarchy process (AHP) and expert consultation method are used to determine the evaluation index system and index weight. Suitability effect of the information service system of "Agricultural science and {1. 1.0" is taken as the target layer. The five indices at criterion layer are the organizational mode of agricultural information service, the support system of agricultural information resources, the agricultural information transfer system, the capital source of agricultural information service, and the support system of agricultural information service. And the index layer includes the talent team of agent service, the interaction between the subject and object, the accuracy of agricultural information, the convenience of agricultural information transfer, the adequacy of fund, the efficiency in the use of fund, the status of information infrastructure and so on. Evaluation result shows that the information service system of "Agricultural science and {1. 1.0" in Sichuan Province is suitable for the rural economic development at present. The major factors restricting the information service system are the lack of continuity, the weak infrastructure of agricultural information infrastructure, and the relatively low education level of agricultural producers. Therefore, we should further explore and improve the operation mechanism of agricultural information service, expand the capital source of agricultural information service, strengthen the construction of agricultural infrastructure, and ensure the continuous operation of information service system.

关键词： Agricultural science and technology 1.0 Agricultur

Synthesis and Lubrication of Phosphorylcholine Derivative

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Journal of Bionic Engineering 2010年第3期7卷 254-258页

作者： Zhenliang Qiao~1. Dangsheng Xiong~1. Lude Lu~2. Pengju Jiang~2.1. Department of Materials science and Engineering, {1. university of science and technology, {1. 2.0}094, P.R. china 2. School of Chemical Engineering, {1. university of science and technology, {1. 2.0}094, P. R. china [a] Department of Materials science Engineering Nanjing University of Science technology Nanjing 210094 P.R. China [b] School of Chemical Engineering Nanjing University of Science technology Nanjing 210094 P. R. China

The monomer of phosphorylcholine derivative, O-(5-（2.methacryloxy）-3, 3-dimethyl-3-azapentyl)-O’-（ω-hydroxy-octyl）-phosphatequaternary ammonium salt, was designed and synthesized successfully. It was characterized by the spectra ofHNMR and Mass spectra （ESI+）, and every signal was assigned. Then the lubricating characteristics of the phosphorylcholinederivative were investigated on the tribological setup of ball-oh-flat. The Ultra-High Molecular Weight Polyethylene（UHMWPE） flat was rotated against a stainless steel ball with 6 mm diameter. The load was 2.3 N, which corresponded to amaximal Hertz contact pressure of 2. MPa. Water, phosphorylcholine derivative, and Acrylic Acid （AA） solution were used aslubricants, respectively. Compared with AA, the phosphorylcholine derivative shows significant lubrication. It can be stronglyhydrated under water due to the charged segment in chemical structure. The thick water layers within the chains serves asboundary lubricants, and this is thought to be the molecular origins of lubricating behavior.

关键词： artificial joint articular cartilage molecular lubrication mechanism phosphorylcholine synthesis UHMWPE

Stability of a linear oscillator with damping force of the fractional-order derivative

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science {1.(Physics,Mechanics & Astronomy) 2010年第2期53卷 345-352页

作者： WANG ZaiHua1,2.& HU HaiYan1 1 Institute of Vibration Engineering Research,nanjing university of Aeronautics and Astronautics,nanjing 2.0016,china 2.Institute of science,pla university of science and technology,nanjing 2.1.01.china 1. Institute of Vibration Engineering Research Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. Institute of Science PLA University of Science and Technology Nanjing 211101 China

It begins with the study of damping representation of a linear vibration system of single degree of freedom (SDOF),from the view point of fractional calculus. By using the idea of stability switch,it shows that the linear term involving the fractional-order derivative of an order between 0 and 2.always acts as a damping force,so that the unique equilibrium is asymp-totically stable. Further,based on the idea of stability switch again,the paper proposes a scheme for determining the stable gain region of a linear vibration system under a fractional-order control. It shows that unlike the classical velocity feedback which can adjust the damping force only,a fractional-order feedback can adjust not only the damping force,but also the elastic re-storing force,and in addition,a fractional-order PDα control can either enlarge the stable gain region or narrow the stable gain region. For the dynamic systems described by integer-order derivatives,the asymptotical stability of an equilibrium is guaranteed if all characteristic roots stay in the open left half-plane,while for the systems with fractional-order derivatives,the asymptotical stability of an equilibrium is guaranteed if all characteristic roots stay within a sector in the complex plane. Analysis shows that the proposed method,based on the idea of stability switch,works effectively in the stability analysis of dynamical systems with fractional-order derivatives.

关键词： vibration system fractional-order derivative asymptotical stability stability switch

Delayed Hopf bifurcation in time-delayed slow-fast systems

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science {1.(Technological sciences) 2010年第3期53卷 656-663页

作者： ZHENG YuanGuang1 & WANG ZaiHua1,2.1 Institute of Vibration Engineering Research,nanjing university of Aeronautics and Astronautics,nanjing 2.0016,china 2.Institute of science,pla university of science and technology,nanjing 2.1.01.china 1. Institute of Vibration Engineering Research Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. Institute of Science PLA University of Science and Technology Nanjing 211101 China

This paper presents an investigation on the phenomenon of delayed bifurcation in time-delayed slow-fast differential *** the two delayed's have different *** delayed bifurcation means that the bifurcation does not happen immediately at the bifurcation point as the bifurcation parameter passes through some bifurcation point,but at some other point which is above the bifurcation point by an obvious *** a time-delayed system,the evolution of the system depends not only on the present state but also on past *** this paper,the time-delayed slow-fast system is firstly simplified to a slow-fast system without time delay by means of the center manifold reduction,and then the so-called entry-exit function is defined to characterize the delayed bifurcation on the basis of Neishtadt's *** shows that delayed Hopf bifurcation exists in time-delayed slow-fast systems,and the theoretical prediction on the exit-point is in good agreement with the numerical calculation,as illustrated in the two illustrative examples.

关键词： time delay delayed bifurcation Hopf bifurcation slow-fast systems exit-point entry-exit function

Three-dimensional elasticity solution of simple-supported rectangular plate on point supports, line supports and elastic foundation

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science {1.(Technological sciences) 2009年第3期52卷 584-589页

作者： XU YePeng1.& ZHOU Ding2.1.School of {2., {1. university of {2. and technology, {1. 2.0}094, china 2.College of Civil Engineering, {1. university of technology, {1. 2.0}009, china 1. School of science Nanjing University of Science and Technology Nanjing 210094 China 2. College of Civil Engineering Nanjing University of Technology Nanjing 210009 China

This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacement functions, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived. The reaction forces of the in- termediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Comparing the numerical results obtained from the proposed method to those obtained from Kirchhoff plate theory, Mindlin plate theory and those obtained from the commer- cial finite element software ANSYS, the high accuracy of the present method has been demonstrated.

关键词： rectangular plate point support line support elastic foundation displacement stress three-dimensional elasticity solution

Basic study on architectural planning of psychiatric hospital

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science {1.(Technological sciences) 2010年第7期53卷 1755-1767页

作者： ZHOU Ying1.& SUN YaoNan2.1.Southeast {2., {1. 2.0}096, china 2.{1. {2. of science & technology, {1. 2.0}094, china 1. Southeast university Nanjing 210096 China2. Nanjing University of Science & Technology Nanjing 210094 China

This paper considers the main problems of the current mental health facilities in china from the standpoint of architects on the background that mental disorder has become a serious threat to human health. In order to effectively learn from the developed countries, this paper reviews the brief history of the world's mental health and the main phases of the evolution of psychiatric hospitals, analyzes the actual situation of mental health facilities abroad based on a large amount of data, compares the roles of public and private psychiatric hospitals from the viewpoint of government supervision, and investigates the functions and positions of psychiatric hospitals and the psychiatry divisions of general hospitals in the medical system. At last, this paper discusses the necessity of the systemization of mental health facilities, the role of psychiatric hospitals in this facility system and the developing approaches of psychiatric hospitals in china.

关键词： medical facility for mental disorder facility system psychiatric hospital principles

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science {1. Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1.2. XIAO Heming1.& DONG Haishan2.1. Department of Chemistry, nanjing {1. of science and technology, nanjing 2.0}094, china 2. Institute of Chemical Materials, china Academy of Engineering Physics, Mianyang 62.0}00, china 1. Department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Institute of Chemical Materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

Intuitionistic fuzzy hierarchical clustering algorithms

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Journal of Systems Engineering and Electronics 2009年第1期20卷 90-97页

作者： Xu Zeshui1.2.1. Coll. of Economics and Management, Southeast Univ., {2. 2.0}096, P. R. {1. 2. Inst. of sciences, pla Univ. of science and technology, {2. 2.0}007, P. R. {1. Coll. of Economics and Management Southeast Univ. Nanjing 210096 P. R. China Inst. of sciences PLA Univ. of Science and Technology Nanjing 210007 P. R. China

Intuitionistic fuzzy set （IFS） is a set of 2.tuple arguments, each of which is characterized by a membership degree and a nonmembership degree. The generalized form of IFS is interval-valued intuitionistic fuzzy set （IVIFS）, whose components are intervals rather than exact numbers. IFSs and IVIFSs have been found to be very useful to describe vagueness and uncertainty. However, it seems that little attention has been focused on the clustering analysis of IFSs and IVIFSs. An intuitionistic fuzzy hierarchical algorithm is introduced for clustering IFSs, which is based on the traditional hierarchical clustering procedure, the intuitionistic fuzzy aggregation operator, and the basic distance measures between IFSs： the Hamming distance, normalized Hamming, weighted Hamming, the Euclidean distance, the normalized Euclidean distance, and the weighted Euclidean distance. Subsequently, the algorithm is extended for clustering IVIFSs. Finally the algorithm and its extended form are applied to the classifications of building materials and enterprises respectively.

关键词： intuitionistic fuzzy set interval-valued intuitionistic fuzzy set hierarchical clustering intuitionisticfuzzy aggregation operator distance measure.

Case studies on mesoscale structures of heavy rainfall system in the Yangtze River generated by Meiyu front

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science {1. Earth sciences 2005年第8期48卷 1303-1311页

作者： LIU Liping1. RUAN Zheng1.& QIN Danyu2.1. Chinese Academy of Meteorological sciences, Beijing 1.0081. {1. 2. nanjing Institute of meteorology, nanjing 2.0}044, {1. 1. Chinese Academy of Meteorological sciences 100081 Beijing China 2. nanjing Institute of {1. 210044 Nanjing China

A heavy rainfall system was observed over the Yangtze River during Meiyu season by using dual-Doppler radar systems in the field experiment conducted by the project of National Fundamental Research planning “Research on formation mechanism and the prediction theory of hazardous weather over {1.”. The three-dimensional mesoscale kinematic structure and process of a heavy rain on 2. and 2. July, 2.02.are investigated by using the radial velocity and dual-Doppler radar technique. The results show that a southwest-northeast oriented rain band with the length of about 1.00 km involves numbers of meso-β or meso-γ-scale convective cells with the size of 2.―50 km. The heavy rain band in the middle reaches of the Yangtze River ex-ists in a low-level wind shear. The interaction between southwest low-level jet on the southern side of wind shear and east wind on the northern side formed the updraft. The wind disturbance, wind shear and convergence generate the convective action. The new cell developed in right rear flank of rain band and moved to the southwest wind area, where the vapor is abundant. This kind of echo can last a long time and developed well. The strong convective echoes are often ac-companied by the meso-γ-scale vortex and convergence.

关键词： heavy rainfall in Meiyu front, mesoscale structure, dual-Doppler radar, middle reaches of the Yangtze River, low-level jet.