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    题名 作者 年代 出处 被引量
1A New Manganese(Ⅱ) Coordination Compound Constructed by 1,10-Phenanthroline Derivative and Chlorine Anions: Synthesis, Crystal Structure and Theoretical Calculation显示文摘The new manganese(Ⅱ) coordination compound,[Mn(Cl)2(L)2](1, L = 11-fluorodipyrido[3,2-a:2?,3?-c]phenazine), has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction. 1 crystallizes in monoclinic system, space group C2/c with a = 8.419(2), b = 12.286(2), c = 28.451(6)A,β= 95.889(3)°, V =2927.5(10)A3, Z = 4, C36 H16 MnF2 Cl2 N8, Mr = 724.41, Dc = 1.644 g/cm3, F(000)= 1460,μ(Mo Ka)= 0.691 mm-1, R = 0.0445 and wR = 0.0982. Adjacent compounds are stacked by one type of π-πinteraction among L ligands to generate a 1D supramolecular chain. Further, the 1D supramolecular chains are stacked by another type of π-π interaction among L ligands to give a 2D supramolecular layer. Moreover, the C-F···π interactions between the carbon atom of the L ligand and the pyrazine ring of the adjacent L ligand further stabilize the supramolecular layer of 1. In addition, natural bond orbital(NBO) analysis has been calculated by the B3LYP/LANL2DZ method, which shows obvious covalent interaction between the coordinated atoms and Mn(Ⅱ) ion.WANG Xiu-Yan GAO Wen-Yu ZHOU Xiao-Hang LIU Dong-Xue HU Bo KONG Zhi-Guo 2019Chinese Journal of Structural Chemistry2019,38,5:4
2Abutment pressure distribution for longwall face mining through abandoned roadways显示文摘Abutment pressure distribution is different when a longwall panel is passing through the abandoned gate roads in a damaged coal seam. According to the geological condition of panel E13103 in Cuijiazhai Coal Mine in China, theoretical analysis and finite element numerical simulation were used to determine the front pressure distribution characteristics when the longwall face is 70, 50, 30, 20, 10, and 5 m from the abandoned roadways. The research results show that the influence range of abutment pressure is 40 to 45 m outby the face, and the peak value of front abutment pressure is related to the distance between the face and abandoned roadways. When the distance between the longwall face and abandoned roadways is reduced from 50 to 10 m, the front abutment pressure peak value kept increasing. When the distance is 10 m, it has reached the maximum. The peak value is located in 5 to 6 m outby the faceline. When the distance between the longwall face and abandoned roadways is reduced from 10 to 5 m, the front abutment pressure sharply decreases, the intact coal yields and is even in plastic state. The peak value transfers to the other side of the abandoned roadways. The research results provide a theoretical basis for determining the advance support distance of two roadways in the panel and the reinforcement for face stability when the longwall face is passing through the abandoned roadways.Yang Li Mingxing Lei Haosen Wang Cheng Li Weiwei Li Yang Tao Jingyi Wang 2019International Journal of Mining Science and Technology2019,29,1:4
3Theoretical study on primary reaction of photosynthetic bacteria显示文摘Theoretical calculation was carried out on the primary electron donor P870 of photosynthetic bacteria. The results show that: (ⅰ) the bimolecular structure of the primary electron donor is more advantageous in energy than monomolecular structure; (ⅱ) the initial configuration of primary electron donor is no longer stable and changes to the configuration with lower energy and chemical reactivity after the charge separation. In the P870, such structural change is completed through the rotation of C3 acetyl, so the oxygen atom of acetyl interacts with the magnesium atom of another bacterio-chlorophyll molecule, and the total energy and chemical reactivity are reduced evidently. It is suggested that the structural change of the primary electron donor is important in preventing the occurrence of charge recombination during the primary reaction and maintaining the high efficiency of the conversion of sun-light to chemical energy. A new mechanism of primary reaction has been proposed, which can give张纯喜 樊红军 李良璧 匡廷云 1999Science China(Life Sciences)1999,42,2:2
4Multi-carbazole derivatives for two-photon absorption data storage:Synthesis,optical properties and theoretical calculation显示文摘Two novel quadrupolar organic compounds, 3-(4-((E)-2-(9-butyl-9H-carbazol-6-yl) vinyl)styryl)-9-propyl-9H-carbazole (BCSPC) and 3-(3-(3-((1E)-2-(4-((E)-2-(3-(3,5-bis(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazol-6-yl)vinyl)phenyl) vinyl)-9-butyl-9H-carbazol-6-yl)-5-(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazole (BCPBC), with different conjugated arms, have been designed and synthesized. Their one-and two-photon absorption (TPA) and excited fluorescence properties have been experimentally investigated. The two-photon absorption cross-sections of two compounds were estimated by two-photon excited fluorescence technique using 200 fs, 76 MHz, Ti:sapphire laser, which are 22 and 154 GM for BCSPC and BCPBC, respectively. The optimal excitation wavelengths are 780 nm for both BCSPC and BCPBC. A data recording experiment proved the potential application of the materials.LI Lin1, YANG JiaXiang1,2, WANG CaiXia1, HU ZhangJun1, TIAN YuPeng1,2, LI Jing3, WANG ChuanKui3, LI Ming4, CHENG GuangHua4, TANG HuoHong5, HUANG WenHao5, TAO XuTang2 & JIANG MinHua2 1Department of Chemistry, Anhui University, Hefei 230039, China 2State Key Laboratory of Crystal Materials, Institute of Crystal Materials of Shandong University, Jinan 250100, China 3Department of Physics, Shandong Normal University, Jinan 250014, China 4State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China 5Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei 230026, China 2010Science China Chemistry2010,53,4:2
5Numerical study of fillet weld leg height of sleeve repair welding for in-service pipeline显示文摘This paper presents a mechanical calculation and numerical simulation of the fillet weld of sleeve repair.The mechanical analysis based on the yield criteria is performed to obtain the minimum value of the fillet weld leg height to ensure the strength and loadbearing capacity of the weld. Within the framework of numerical simulation,the parameters of double ellipsoid heat source are determined by fitting method and the simulated molten pool morphology agrees well with the practical weld. Finite element models with various weld leg height are performed to predict the distribution and magnitude of the deformation and stress. The simulation takes into account thermal,metallurgical and mechanical factors,and the maximum value of the fillet weld leg height is obtained based on the magnitude of the deformation and stress.The mechanical calculation and numerical simulation results show that 1.2-2 times wall thickness is an optimal range of fillet weld leg height. And reasonable parameters of sleeve repair for in-service welding are provided for engineering field,which can improve the service life of the weld and production efficiency.乔羚 韩涛 张洪杰 吴倩 鲍亮亮 2018China Welding2018,27,1:2
6Theoretical calculation and evaluation of n +^(240,242,244)Pu reactions显示文摘The nuclear data of n+^(240;242;244)Pu reactions for incident energy below 200 MeV are calculated and evaluated to meet the requirement in the design of an accelerator-driven subcritical system. The optical model is used to calculate the total, nonelastic, shape elastic cross sections, shape elastic scattering angular distributions, and transmission coefficients. The distorted-wave Born approximation is applied to calculate the direct inelastic scatterings to the discrete excited states. The nuclear reaction statistical models and fission theory are applied to describe neutron, proton, deuteron, triton, helium-3, alpha and c emissions, and fission consistently. The results thus obtained are compared with experimental data and the evaluated data obtained from ENDF/B-VII.1 and JENDL-4.0.Hai-Rui Guo Yin-Lu Han Chong-Hai Cai 2019Nuclear Science and Techniques2019,30,1:2
7Theoretical study of substituent effect on the charge mobility of 2,5-bis(trialkylsilylethynyl)-1,1,3,4-tetraphenylsiloles显示文摘The theoretical calculation of the charge mobility of 2,5-bis(trialkylsilylethynyl)-1,1,3,4-tetraphenylsiloles is presented.B3LYP/6-31* calculations demonstrated that these silole molecules possessed large coupling matrix elements and reorganization energies for electron and hole transfers and high electron mobilities.The bulkiness of the trialkyl substituents influenced the charge mobility of the silole molecules,with the smaller trimethyl group imparting higher charge mobility than triethyl and triisopropyl substituents.LAM Jacky Wing Yip 2010Science China Chemistry2010,53,11:1
8The role of central ion in chiral recognition by taking phenylalanine as an example显示文摘Chiral recognition of phenylalanine(Phe) was achieved in the gas phase by electrospray ionization Q-TOF tandem mass spectrometry.In this method,two central ions,i.e.proton and divalent copper,were used and chiral crown ether,(+)-2,3,11,12-tetracarboxylic acid-18-crown-6(18-C-6-TCA),was used as a chiral host.Dimeric complexes were readily formed by electrospray ionization of a methanol/water(50/50,V/V) solution containing central ions,Phe and 18-C-6-TCA.The dimeric complex included proton-bound(18-C-6-TCA)(Phe)H+ and copper-bound deprotonated [Cu2+(18-C-6-TCA)(Phe)-H]+ ions were mass selected and then collided with Ar in the CID experiments.The chiral recognition capability of these complexes was evaluated using the relative abundance of daughter ion to parent ion.A higher degree of chiral recognition ability was observed with Cu2+ compared to that of H+.Different central ions exhibited distinctive dissociation pathways and unique chiral recognition characteristics.The chiral recognition mechanism was also discussed in detail with the help of the structure of copper-bound complex predicted by theoretical calculation.YU Qing CAO Jie LU Gang WANG ZhiXiang 2009Science China Chemistry2009,52,8:0
9Intermolecular Magnetic Coupling Mechanism for a New Ionic Pair Salt [Ni(bpy)3][Ni(mnt)2]2显示文摘A new ionic pair salt[Ni(bpy)3][Ni(mnt)2]2(mnt=1,2-dicyanoethane-1,2-dithiolate)has been prepared and its crystal structure was determined by X-ray crystallography at 293,200 and 100 K.In the mononuclear radical anionic complex,the nickel ion assumes a slightly distorted square-planar geometry.There is a special kind of stacking interactions at each temperature(i.e.,Model A at 293 K,Model B at 200 K and Model C at 100 K).The variable-temperature magnetic moments indicate that there is a strong anti-ferromagnetic interaction between the adjacent p-p stacking mononuclear radical anionic complexes and especially the anti-ferromagnetic coupling strength is close to the diamagnetism at 100 K.The theoretical calculations reveal for the first time that the spin densities between the short contact atoms areβstate and the anti-ferromagnetic coupling property of this crystal may be related to theβstate spin densities between the short contact atoms.The theoretical calculations further confirm that the strong anti-ferromagnetic coupling strength should be relevant to the larger spin densities on the short contact atoms and the larger overlap integrals between the short contact atoms.刘连栋 郑鲁沂 陈雪雪 迟颜辉 石敬民 陈德展 2019Chinese Journal of Structural Chemistry2019,38,10:0
10Blue-emissions Modulated by Packing Forces in Alkaline-earth Metal OrganicFrameworks Based on Thiophene-2,5-dicarboxylic: Structures and Theoretical Calculations显示文摘Solvothermal reactions of Ca(NO_3)_2, Sr(NO_3)_2 with thiophene-2,5-dicarboxylic in DMF afforded two new inorganic-organic hybrid frameworks, [M(TDC)(DMF)]n(M = Ca(1), Sr(2), TDC = thiophene-2,5-dicarboxylic, DMF = N,N?-dimethylformamide), which have been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis and IR spectra. Both compounds feature three-dimensional(3D) frameworks based on the versatile coordinated modes(μ_3-η~2:η~2, μ_3-η~2:η~1, μ_2-η~2:η~1) of carboxylic groups in tdc ligands. C–H···S hydrogen bonds and C–H···π interactions contribute to the stabilization of the structures. They exhibit weaker packing force compared with their literature isomers. Consequently, blue and blue/green luminescence of two compounds has been observed. Their luminescence mechanism can be ascribed to ligand-to-metal charge transfer(LMCT) compared with the ligand-centered luminescence in their isomers. Electronic structural calculations illustrate that under the condition of weaker packing forces, larger gaps can be achieved, which facilitate the LMCT. This work suggests that the introduction of S-heteroatom can result in more electrons rich in the metal centers, thus giving rise to metal-involved luminescence.陈家越 2018Chinese Journal of Structural Chemistry2018,37,12:0
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