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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 2.0094, china 2. institute of chemical materials, china Academy of Engineering Physics, mianyang 62.900, 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).

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Research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural Science:materials International 2005年第5期15卷 385-394页

作者： GONG Yun1, HU Changwen1* and LIANG Hong2.1. Department of Chemistry, School of Science, the institute for chemical Physics, Beijing institute of Technology, Beijing 100081, china 2. chemical Industry Press, Beijing 10002., china) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2.02.2.04) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.

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Theoretical calculation of the finishing rolling impact work in non-quenched and tempered Si-Mn steel

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Science china(Technological Sciences) 2006年第2期49卷 137-146页

作者： LIU Zhilin1, LIN Cheng1 & WANG Ping2.1. Department of materials and chemical Engineering, Liaoning {2. of Technology, Jinzhou 12.001, china 2. Mechanical Department, Armor technique {2. of PLA, Changchun 130117, china Department of materials chemical Engineering Liaoning Institute of Technology Jinzhou 121001 China Mechanical Department Armor technique Institute of PLA Changchun 130117 China

Based on the hot-continuous rolling technology, the finishing rolling impact work α k of the non-quenched and tempered Si-Mn steel is theoretically calculated with the covalent electron number nA of the strongest bond in alloying phases, and the smallest interface electron density difference Δρ of alloying phase interface and the number of atom states σ which keep the interface electron density continuous. Calculations show that the solution strengthening, the precipitation strengthening, and the interface strengthening will result in the decrease of the finishing rolling impact work α k, and the effects of the number of atom states σ which keep the interface electron density continuous on the finishing rolling impact work α k are different. Taking the impact work and the number of atom states σ 0 keeping the electron density continuous of the phase interface α-Fe/α-Fe-C between α-Fe and α-Fe-C as reference values, the impact work of the interface will increase when σ of some interface is larger than σ 0; otherwise, the impact will decrease. Therefore, the finishing rolling impact work α k can be calculated with the impact value of the refined α-Fe matrix and the influence amounts caused by the solution strengthening, the precipitation strengthening, the interface strengthening, and the number of atom states σ which keep the interface electron density continuous. The calculated results agree well with the measured ones. In this paper, the effect of S on the impact work is also discussed.

关键词： electron structure parameters, non-quenched and tempered steel, impact work and calculation.

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Theoretical calculation of the impact work in the alloying non-quenched and tempered steel

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Science china(Technological Sciences) 2006年第3期49卷 257-273页

作者： LIU Zhilin1, LIN Cheng1 & GUO Yanchang2.1. Department of materials and chemical Engineering, Liaoning {2. of Technology, Jinzhou 12.001, china 2. The Technical Center of Benxi Iron and Steel Group Corporation, Benxi 117000, china Department of materials chemical Engineering Liaoning Institute of Technology Jinzhou 121001 China The Technical Center of Benxi Iron Steel Group Corporation Benxi 117000 China

Coupled with hot-continuous rolling technology and based on the calculation of the finishing rolling impact work in the non-quenched and tempered Si-Mn steel, the calculations of the finishing rolling impact work in the alloying non-quenched and tempered steel with the elements of Cr, Ni, Mo, W, Cu, V, Nb and Ti are studied with the covalent electron number nA of the strongest bond in alloying phases, the smallest electron density difference ?ρ of phase interfaces, and the number of atom states σ (σ′) which keep the interface electron density continuous. The calculated results show that the finishing rolling impact work of the alloying non-quenched and tempered steel intensely depends on strengthening mechanisms. The solution strengthening, interface strengthening, precipita- tion strengthening of pearlite, and dispersion strengthening will result in the decrease of the finishing rolling impact work; the refinement strengthening, the precipitation strength- ening of V, Nb and Ti in α-Fe-C-V(Nb, Ti), and the residual austenite containing Ni on the boundary of α-Fe-C-Ni will increase the impact work; and the increments or decrements can be calculated with nA, ?ρ, σ (σ′) and weights of alloying elements. The calculation formulas of the finishing rolling impact work in this paper are intergraded with the sug- gested ones of the finishing rolling tensile strength, yield strength, and elongation of the non-quenched and tempered steel. The calculated results agree well with the measured ones.

关键词： alloying non-quenched and tempered steel, electron structure, impact work, calculation.

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Ab initio Calculation of Intermolecular Dispersion Energy and Induction Energy of Nitramide Dimer

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Chinese Journal of Chemistry 2004年第11期22卷 1377-1381页

作者：宋华杰肖鹤鸣董海山institute of chemical {2. china Academy of Engineering Physics mianyang Sichuan 62.900 china 黄奕刚institute of chemical {2. china Academy of Engineering Physics mianyang Sichuan 62.900 china 龙新平institute of chemical {2. china Academy of Engineering Physics mianyang Sichuan 62.900 china 汤业鹏institute of chemical {2. china Academy of Engineering Physics mianyang Sichuan 62.900 china Department of Chemistry Nanjing University of Science and Technology Nanjing Jiangsu 210094 China institute of chemical {2. China Academy of Engineering Physics Mianyang Sichuan 621900 China

The dispersion energies, induction energies and their exchange counterparts (exchange-dispersion and ex-change-induction energies) between two interacting nitramide molecules at several separations are derived based upon symmetry-adapted perturbation theory (SAPT). The results show that (1) the effect of intramonomer electron correlation on dispersion energies and induction energies for nitramide dimer system is remarkable especially in the region near the van der Waals minimum distance (0.42.nm). (2. At smaller separations the dispersion energies and the induction energies are largely quenched by their exchange counterparts, and this case in induction interaction is much more remarkable than in dispersion interaction. (3) Since at shorter distances there exists the strong short-range interaction due to electron transfer which quickly decays and even disappears at larger separations, the two different R-dependency formulae of induction energies were found: one is ca. R-12.7 at short distances, and the other ca. R-7.0 at large separations. The latter R-dependency is similar to that (ca. R-7.2. of dispersion. (4) In the case of strong polar interaction existing in nitramide dimer, the true induction correlation terms of higher order than t(2.)indE may be important.

关键词： dispersion energy induction energy nitramide dimer symmetry-adapted perturbation theory

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Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1,3, SUN Weiguo1,2.& FENG Hao1 1. institute of Physics, Sichuan University, Chengdu 610065, china 2. College of {2. Engineering, Sichuan University, Chengdu 610065, china 3. mianyang Teacher抯 College, mianyang 62.000, china Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) 1. institute of Physics Sichuan University 610065 Chengdu China 2. mianyang Teacher's College 621000 Mianyang China 3. College of chemical Engineering Sichuan University 610065 Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2. state of CO+, the X2. g + state of Li 2.+ , the X2. g + state of He 2.+ , the 12.u state of Na 2.+ , the A2.u state of N 2.+ , the X1∑+ state of KrH+, the X2.+ state of SiO+ and the A2. state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.

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Calculation of the yield and tensile strength in the alloying non quenched-tempered steel by the electron structure parameters

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Progress in Natural Science:materials International 2005年第9期15卷 832-837页

作者： LIU Zhilin1**, LIN Cheng1, LIU Yan1 and GUO Yanchang2.1. Department of materials and chemical Engineering, Liaoning {2. of Technology, Jinzhou 12.001, china 2. The Technical Center of Benxi Iron and Steel Group Corporation, Benxi 117000, china) Department of materials and chemical Engineering Liaoning Institute of Technology Jinzhou 121001 China. Technical Center of Benxi Iron and Steel Group Corporation Benxi 117000 China

Based on the phase transformations and strengthening mechanisms during rolling, the strength increments Δσbunder different strengthening mechanisms are calculated with the covalent electron number nAof the strongest bond in phase cells of alloys and the interface electron density difference Δρ matching the interface stress in alloys. The calculation method of the finishing rolling yield strength is proposed, and it is integrated with the proposed calculation formulas of strength of non quenched-tempered steel. Therefore, the general formulas to simultaneously calculate both the finishing rolling strength and the yield strength of the continuous casting-rolling and non quenched-tempered steel are given. Taken the pipeline steel X70 as an example, the predictions of properties and technological parameters are performed before production or online.

关键词： electron structure non quenched-tempered steel yield strength prediction of properties.

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Theoretical study of ZnO adsorption and bonding on Al_2._3(0001) surface

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2.XUE Weidong1,LI Jinshan3 & LIU Yonghua3 1.institute of Microelectronics and Solid State Electronics,University of Electronic Science and Technol- ogy of china,Chengdu 610054,{2. 2.institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,{2. 3.institute of chemical materials,{2. Academy of Engineering Physics,mianyang 62.000,{2. institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China institute of chemical {2. China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 434.3(±38.6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 30° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 30°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2.of the ZnO ? and the surface Al3+ has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2. and the surface O2.has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2. and partially from that of the Zn 3d and the O 2..

关键词： α-Al2.3 (0001) ZnO ab initio molecular dynamics chemical adsorption density of states

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Preparation of graphitic carbon nitride by electrodeposition

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Chinese Science Bulletin 2003年第16期48卷 1737-1740页

作者： LI Chao1,2. CAO Chuanbao1 & ZHU Hesun1 1. Research Center of materials Science, Beijing institute of Technology, Beijing 100081,{2. 2. Department of chemical Engineering, Zhengzhou institute of Light Industry, Zhengzhou 450002.china Correspondence should be addressed to Cao Chuanbao Research Center of materials Science Beijing Institute of Technology Beijing 100081 China Department of chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China

The CNx thin film was deposited on Si(100) substrate from a saturated acetone solution of cyanuric tri-chloride and melamine (cyanuric trichloride/melamine=1︰1.5) at room temperature. X-ray diffraction (XRD) results showed that the diffraction peaks in the pattern coincided well with those of graphite-like carbon nitride calculated in the literature. The lattice constants (a=4.79 ? c=6.90 ) for g-C3N4 matched with those of ab initio calculations (a=4.74 ? c=6.72.? quite well. X-ray photoelectron spectroscopy (XPS) measurements indicated that the elements in the de-posited films were mostly of C and N (N/C=0.75), and N (400.00 eV) bonded with C (2.7.72.eV) in the form of six-member C3N3 ring. The peaks at 800 cm-1, 1310 cm-1 and 1610 cm-1 in the Fourier transform infrared (FTIR) spec-trum indicated that triazine ring existed in the product. These results demonstrated that crystalline g-C3N4 was ob-tained in the CNx film.

关键词：沉淀薄膜饱和丙酮溶液三聚氰胺 X射线衍射石墨碳氮化合物晶格恒量光电子光谱测量法傅立叶变换红外光谱三嗪

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Preparation and Adsorption Property of Hydrophobic SiO_2.Aerogels Modif ied by Methyl Triethoxysilane

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Journal of Wuhan University of Technology(materials Science) 2011年第6期26卷 1079-1083页

作者：崔升 State Key Laboratory of materials-oriented chemical Engineering College of Materials Science and EngineeringNanjing University of Technology

The hydrophobic SiO2.aerogels were prepared by in-situ polymerization sol-gel method and supercritical drying of ethanol method with tetraethylorthosilicate（TEOS） as silica source, methyl triethoxysilane （MTMS） as modifier, ethanol as solvent. Moreover, the structure and adsorption property of SiO2.aerogels were also studied. As results, the surface area of SiO2.aerogels was 863.59 m2.g, the pore volume was 3.57 cm3/g, and the contact angle was 150 °. Adsorption intensity of silica aerogels for organic liquid （alkanes, benzene compounds, and nitro-compounds） is bigger than that of activated carbon. The mass of the liquid absorbed increased linearly with the surface tension of the liquid. The lower surface tension and boiling point are, the shorter desorption time is. After regenerating 10 times, nitromethane regeneration rate remain the same, and almost more than 94%. So SiO2.aerogels have good absorption and regeneration property.

关键词： SiO2.aerogels hydrophobic adsorption intensity adsorption desorption regeneration

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