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science china 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 university of science and technology, nanjing 210094, china 2. Institute of Chemical Materials, china Academy of Engineering Physics, Mianyang 621900, china Department of Chemistry Nanjing University of Science and Technology Nanjing China Institute of Chemical Materials China Academy of Engineering Physics 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).

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On the reconstruction of Dirichlet-to-Neumann map in inverse scattering problems with stability estimates

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science china Mathematics 2010年第8期53卷 2069-2084页

作者： WANG HaiBing 1,2 & LIU JiJun 1 1 Department of Mathematics,Southeast university,nanjing 210096,china 2 school of Mathematics and Computational science,Hunan university of science and technology,Xiangtan 411201,china Department of Mathematics Southeast University Nanjing China school of Mathematics and Computational science Hunan University of Science and Technology Xiangtan China

Consider the determination of Dirichlet-to-Neumann(D-to-N) map from the far-field pattern in inverse scattering problems,which is the key step in some recently developed inversion schemes such as probe ***,this problem is related to the reconstruction of the scattered wave from its far-field *** firstly prove the well-known uniqueness result of the D-to-N map from the far-field pattern using a new scheme based on the mixed reciprocity *** advantage of this new proof scheme is that it provides an efficient algorithm for computing the D-to-N map,avoiding the numerical differentiation for the scattered *** combining with the classical potential theory,a simple and feasible regularizing reconstruction scheme for the D-to-N map is *** the stability estimate for the reconstruction with noisy input data is rigorously analyzed.

关键词： inverse scattering Dirichlet-to-Neumann map regularization mixed reciprocity principle stability

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An elastic-plastic analysis of short-leg shear wall structures during earthquakes

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 525-540页

作者： Ding Jianguo Zhu Ying school of sciences Nanjing University of Science and Technology Huaxin Consulting CO. Ltd

Short-leg shear wall structures are a new form of building structure that combine the merits of both frame and shear wall structures. Its architectural features, structure bearing and engineering cost are reasonable. To analyze the elastic-plastic response of a short-leg shear wall structure during an earthquake, this study modified the multiple-vertical-rod element model of the shear wall, considered the shear lag effect and proposed a multiple-vertical-rod element coupling beam model with a new local stiffness domain. Based on the principle of minimum potential energy and the variational principle, the stiffness matrixes of a short-leg shear wall and a coupling beam are derived in this study. Furthermore, the bending shear correlation for the analysis of different parameters to describe the structure, such as the beam height to span ratio, short-leg shear wall height to thickness ratio, and steel ratio are introduced. The results show that the height to span ratio directly affects the structural integrity; and the short-leg shear wall height to thickness ratio should be limited to a range of approximately 6.0 to 7.0. The design of short-leg shear walls should be in accordance with the ＂strong wall and weak beam＂ principle.

关键词： short-leg shear wall multiple-vertical-rod element model shear lag effect bending shear correlationcoefficient coupling beam stiffness matrix elastic-plastic analysis

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A method of constructing a database-free optimal dynamical system and a global optimal dynamical system

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 905-915页

作者： WU ChuiJie1? & WANG Liang2 1 State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian university of technology, Dalian 116024, china 2 Research Center for Fluid Dynamics, school of science, PLA university of science and technology, nanjing 211101, china State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian China Research Center for Fluid Dynamics School of Science PLA University of Science and Technology Nanjing China

In this paper, to overcome the drawbacks of POT which minimize the reminder, not only the optimal functional with minimal residual is put forward, but also the method of global optimization is used. Under the condition of large reminder, the optimal bases can also be obtained through the method of POTres without the approaching of initial conditions. In addition, compared with local optimization, the advantage of global optimization is remarkable. On the one hand, we can expect that the dynamical system based on the global optimal bases will include more information than the ones based on the local optimal bases, since the global optimal bases are much more precise than the local optimal bases. On the other hand, from the point of view of error, the global optimal bases are independent of the choice of the object functional and the initial bases.

关键词： dynamical system residual global optimization

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Carbon Solubility and Mass Action Concentrations of Fe-Cr-C Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 86-91页

作者： Jtan Zhang(Metallurgy school, university of science and technology Beijing, Beijing 100083, china) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

An empirical equation of carbon solubility in Fe-Cr-C melts is regressed based on the experimental data from references. Acalculating model of mass action concentrations for these melts is formulated on the basis of the coexistence theory of metaIlic melts in-volving compound formation, the phase diagram of Cr-C system as well as thermodynamic data of Fe-Cr-C melts. According to the mod-el, the standard Gibbs free energies of formation of CrC and Cr3C2 are obtained. Satisfactory agreement between the calculated and me-asured values shows that the model can reflect the structural characteristics of Fe-Cr-C melts.

关键词： activity, coexistence theory mass action concentration saturated state

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Aerodynamic/Stealthy/Structural Multidisciplinary Design Optimization of Unmanned Combat Air Vehicle

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Chinese Journal of Aeronautics 2009年第4期22卷 380-386页

作者： Hu Tianyuan,Yu Xiongqing Key Laboratory of Fundamental science for National Defense-Advanced Design technology of Flight Vehicle,nanjing university of Aeronautics and Astronautics,nanjing 210016,china Key Laboratory of Fundamental science for National Defense-Advanced Design technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

An optimization strategy is proposed to deal with the aerodynamic/stealthy/structural multidisciplinary design optimization （MDO） issue of unmanned combat air vehicle （UCAV）. In applying the strategy, the MDO process is divided into two levels, i.e. system level optimization and subsystem level optimization. The system level optimization is to achieve optimized system objective （or multi-objective） through the adjustment of global external configuration design variables. The subsystem level optimization consists of the aerodynamic/stealthy integrated design and the structural optimization. The aerodynamic/stealthy integrated design aims at achieving the minimum aerodynamic drag coefficient under the constraint of stealthy requirement through the adjustment of local external configuration design variables. The structural optimization is to minimize the structural weight by adjusting the dimefisions of structural components. A flowchart to implement this strategy is presented. The MDO for a flying-wing configuration of UCAV is employed to illustrate the detailed process of the optimization. The results indicate that the overall process of the surrogate-based two-level optimization strategy can be implemented automatically, and quite reasonable results are obtained.

关键词： aircraft design multidisciplinary design optimization aerodynamics radar cross section structure

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Applicability of mass action law to sulphur distribution between slag melts and liquid iron

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Journal of university of science and technology Beijing 2002年第2期9卷 90-98页

作者： Jian Zhang Metallurgy school, university of science and technology Beijing, Beijing 100083, china Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

According to the mass action law and the coexistence theory of slagstructure, the calculating models of mass action concentration for CaO-MgO-FeO-Fe_2O_3-SiO_2,CaO-MgO-MnO-FeO-Fe_2O_3-P_2O_5-SiO_2 and CaO-MgO-MnO-FeO-Fe_2O_3-Al_2O_3-P_2O_5-SiO_2 slag melts areformulated and sulphur distribution between the slag melts and liquid iron is treated. It is foundthat CaO, MnO and FeO promote desulphurization, while MgO is detrimental to desulphurization. Inaddition, the sulphur distribution coefficients between the slag melts and liquid iron andpresented.

关键词： mass action law coexistence theory of slag structure activity massaction concentration

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Influence of mesoscale topography on vortex intensity

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Progress in Natural science:Materials International 2008年第1期18卷 71-78页

作者： Zhexian Luo*,Yun Gao Remote Sensing College,nanjing university of Information science and technology,Najing 210044,china Remote Sensing College Nanjing University of Information Science and Technology Najing 210044 China

The effect of mesoscale topography on multi-vortex self-organization is investigated numerically in this paper using a barotropic prim- itive equation model with topographic *** the initial field there are one DeMaria major vortex with the maximum wind radius rm of 80 km at the center of the computational domain,and four meso-b vortices in the vicinity of rm to the east of the major vortex center. When there is no topography present,the initial vortices self-organize into a quasi-final state flow pattern,i.e.a quasi-axisymmetric vor- tex whose intensity is close to that of the initial major ***,when a mesoscale topography is incorporated,the spatial scale of the quasi-final state vortex reduces,and the relative vorticity at the center of the vortex and the local maximum wind speed remarkably *** possible mechanism for the enhancement of the quasi-final state vortex might be that the negative relative vorticity lump, generated above the mesoscale topography because of the constraint of absolute vorticity conservation,squeezes the center of positive vorticity towards the mountain slope area,and thus reduces the spatial range of the major ***,because the total kinetic energy is basically conservative,the squeezing directly leads to the concentration of the energy in a smaller area,*** strengthening of the vortex.

关键词： Mesoscale topography Vortex Self-organization Intensity change

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Molecular dynamics simulation of mechanical properties of TATB/fluorine-polymer PBXs along different surfaces

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science china Chemistry 2005年第6期48卷 504-510页

作者： XIAO Jijun1, HUANG Yucheng1, HU Yingjie1,2 & XIAO Heming1 1. Department of Chemistry, nanjing university of science and technology, nanjing 210094, china 2. Department of Chemistry, nanjing Xiaozhuang College, nanjing 210017, china Correspondence should be addressed to Xiao Heming (email: xiao@***) Department of Chemistry Nanjing University of Science and Technology Nanjing China Department of Chemistry Nanjing Xiaozhuang College Nanjing China

The mechanical properties of PBXs composed of the well-known insensitive explo-sive TATB (1,3,5-Triamino-2,4,6-trinitrobenzene) crystal and four kinds of typical fluo-rine-polymers, i.e. poly (vinylidene difluoride) (PVDF), polychlorotrifluoroethylene (PCTFE), fluo-rine rubber (F2311) and fluorine resin (F2314) individually, have been simulated by molecular dy-namics (MD) method. The results show that the mechanical properties of TATB can be effectively improved by blending with a small amount of fluorine-polymers. Different mechanical properties of PBXs are obtained by putting fluorine-polymer binders parallel to different crystalline surfaces. The whole effect of improving mechanical properties is found to be (010)?(100)>(001).

关键词： TATB, polymer bonded explosives, mechanical properties, molecular dynamics.

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Algorithm for Computation of Unstructured Real Stability Radius and Its Applications

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 245-250页

作者： Xiaodan Zhang Lequan Min(Applied science school, university of science and technology Beijing, Beijing 100083, china) Applied science school University of Science and Technology Beijing Beijing 100083 China

An algorithm for the computation of the unstructured real stability radius of high dimensional linearsystem is presented. Using the accurate formula of the real stability radius of 2-dimensional system linear systemchecks the algorithm. The result shows that the algorithm is reliable and efficient. As applications, the unstructuredreal stability radii of 2-dimensional Chua's circuit and 3-dimensional piecewise-linear system are calculated, thedynamical orbits of the corresponding perturbed systems are simulated.

关键词： lincar systems stability robustness parameter perturbation computational methods

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