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[Hmim]3PW12O40:A high-efficient and green catalyst for the acetalization of carbonyl compounds

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Chinese Chemical Letters 2010年第6期21卷 678-681页

作者： Yan Dai~a,Bin Dong Li~a,Heng Dao Quan~b,Chun Xu Lü~(a,*) a School of Chemical Engineering,nanjing University of Science and Technology,nanjing 210094,China b National Institute of Advanced Industrial Science and Technology,Ibaraki 3058565,Japan [a] School of Chemical Engineering Nanjing University of Science Technology Nanjing 210094 China [b] National Institute of Advanced Industrial Science Technology Ibaraki 3058565 Japan

[Hmim]PWOwas developed and used in the acetalization of carbonyl compounds in excellent *** ionic liquidheteropoly acid hybrid compound and reaction medium formed temperature-dependent phase-separation system with the ease of product as well as catalyst *** catalyst was recycled more than 10 times without any apparent loss of catalytic activity.

关键词： [Hmim]3PW12O40 Phosphotungstic acid Carbonyl compounds Acetalization Ionic liquid

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固体火箭发动机真实流体输运系数的自动模拟

推进技术 2004年第1期25卷 4-6页

作者：陈军南京理工大学机械工程学院江苏南京210094

为缩短固体火箭发动机的研究周期、降低研究成本和揭示工作机理,需要对其工作过程进行三维数值仿真,但数值计算中许多物性参数如输运系数的确定存在困难,为此主要研究了适合于固体火箭发动机内高温高压下的多组分混合物输运系数的计算方... 详细信息

为缩短固体火箭发动机的研究周期、降低研究成本和揭示工作机理,需要对其工作过程进行三维数值仿真,但数值计算中许多物性参数如输运系数的确定存在困难,为此主要研究了适合于固体火箭发动机内高温高压下的多组分混合物输运系数的计算方法,并通过高级计算机语言管理数据库等方法实现自动计算,可准确快速地计算发动机内流过程中输运系数的变化,为真实模拟发动机的工作过程提供正确的物性参数。

关键词：固体推进剂火箭发动机输运系数流体动力学数值仿真

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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 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).

Polyurethane Grafted Attapulgite as Novel Fillers for Nylon 6 Nanocomposites

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 615-619页

作者：史建设杨绪杰 Key Laboratory for Soft Chemistry and Functional Material of the Ministry Education Nanjing University of Science and Technology

Attapulgite fibers were modified by polyurethane, forming polyurethane grafted attapulgite （AT-PU）, which was confirmed by Fourier transform infrared spectroscopy （FTIR）, X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS）. Nylon 6/AT-PU nanocomposites of different modified attapulgite loadings were prepared by melt blending in a twin screw extruder. Scanning electron microscopy （SEM） observation on the fracture surfaces of the nanocomposites showed not only a uniform dispersion of AT-PU but also a strong interfacial adhesion with the matrix. Differential scanning calorimeter （DSC） and Thermogravimetric analyzer （TGA） were used to illustrate the infiuence of AT-PU particles on the thermal properties of the nylon 6/AT-PU nanocomposites. The results indicated that the addition of attapulgite probably induced the heterogeneous nucleation and was favorable for the formation of γ -crystalline form, and that the higher thermal stability was obtained for the composites.

关键词： polyurethane grafted attapulgite nylon 6 nanocomposites

The renascence of industrial historic buildings——Taking the protective remolding and reusing of Chenguang Mechanical Factory in nanjing as an example

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Science China(Technological Sciences) 2009年第9期52卷 2502-2509页

作者： WANG YanHui Research Institute of Architecture,Southeast University,nanjing 210096,China 1. Research Institute of Architecture Southeast University Nanjing 210096 China

The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taking a specific example,makes a systematic discussion on the design strategy and method from the aspects of overall planning,remolding the old buildings,designing the new buildings,etc.

关键词： industrial historic buildings and sites protective remolding and reusing renascence strategy

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火箭弹发射过程冲击流场压力和温度实验测量

推进技术 2003年第6期24卷 514-516,520页

作者：徐强南京理工大学机械工程学院江苏南京210094

考虑燃气流场的冲击效应,根据冲击特点对燃气作用区域的装置结构和强度进行合理的设计,以获得有效的导流和防护效果。实验对火箭发射阶段管后冲击流场在平面斜钢板上的流动参数进行了测量。得到了火箭燃气射流对倾斜钢板热冲击的最大滞... 详细信息

考虑燃气流场的冲击效应,根据冲击特点对燃气作用区域的装置结构和强度进行合理的设计,以获得有效的导流和防护效果。实验对火箭发射阶段管后冲击流场在平面斜钢板上的流动参数进行了测量。得到了火箭燃气射流对倾斜钢板热冲击的最大滞止压力和温度,以及冲击流场的压力与温度分布,并确定了管后燃气冲击流场的危险区域。

关键词：火箭发动机燃气流冲击影响压力测量温度测量

Numerical Analysis on Soil and Rock Formation of Ancient Gravel Strata Around nanjing

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Pedosphere 2001年第3期11卷 263-269页

作者： XIA JIA and CHEN XINMIN Dept. of Civil Engineering, nanjing Architectural and Civil Engineering institute, nanjing 210009 (China) Dept. of Civil Engineering Nanjing Architectural and Civil Engineering Institute

Research samples were taken from an ancient gravel stratum which is not only a representative soil layer along the middle-lower reaches of the Yangtze River in East China, but also one of the primary Neozoic strata in Naming district. Located mostly on the second and third terraces, the ancient gravel strata formed the geomorphic landscapes of terrace and step. They were complex in constitution, varied widely in stability, of multiple sources, locally derived, and associated with braided streams in the deposition environment. A CIPW (Cross, Iddings, Pirsson and Washington) method modified by the author was used to analyze the soil-rock-forming materials of finer grains (less than 2 mm in size) of the ancient gravel stratum. Results of the analysis showed that the sandy grains were composed of apatite, ilmenite, potassium feldspar, plagioclase, enstatite and free quartz, the clay mainly of kaolinite, and the cement of a combination of silicon, aluminum and iron at a ratio of 46:44:10. In the soil-rock-forming processes, including compactional solidification, water-stable illuviation-cementation t homogeneous overgrowth and so on, the loose soil-rock-forming components gradually changed into consolidated soil and further to the early stage of lithification. Meanwhile, from the analysis, we found that the ancient gravel stratum had been protected by the overlying Xiashu loess or basalt and the overloading resulted in overconsolidated strata. The modified CIPW method was applicable and effective for semi-quantitative analysis.

关键词： ancient gravel stratum numerical analysis soil-rock-forming processes

GLOBAL ATTRACTIVITY OF POPULATION MODELS WITH DELAYS AND DIFFUSION

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Journal of Systems Science & Complexity 2005年第3期18卷 396-403页

作者： QIU Zhipeng Department of Applied Mathematics, nanjing University of Science and Technology, nanjing 210094 Department of Mathematics, University of Science and Technology of China, Hefei 230026, China. Department of Applied Mathematics Nanjing University of Science and Technology 江苏 Nanjing 210094

In this paper, the asymptotic behavior of three types of population models with delays and diffusion is studied. The first represents one species growth in the patch Ω and periodic environment and with delays recruitment, the second models a single species dispersal among the m patches of a heterogeneous environment, and the third models the spread of bacterial infections. Sufficient conditions for the global attractivity of periodic solution are obtained by the method of monotone theory and strongly concave operators. Some earlier results are extended to population models with delays and diffusion.

关键词： delays population models global attractivity reaction-diffusion

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