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Micromechanical analysis of interaction energy for SMA reinforced composite

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中国科学:技术科学 2010年第3期 327-327页

The energy of the interaction between the matrix and the inclusions in shape memory alloy (SMA) reinforced composite is one of the most important and complicated parts in thermodynamic constitutive *** this paper,the interaction energy is derived based on the classical theory of micromechanics and the thermodynamic *** SMA composite is treated as three phases,namely the austenitic phase,the martensite phase and the matrix *** interaction among the three phases is analyzed in a way close to the *** present expression is used to calculate the interaction energy of a typical SMA composite with attentions paid to understand of the effects of the matrix material,the fiber geometry,and the fiber/matrix volume *** is shown that the method developed in this paper is credible compared with the *** useful conclusions are obtained.

关键词： shape memory alloy interaction energy SMA composite micromechanics thermodynamics

Geometric and Electronic Structure of Squaric Acid from DFT Calculation

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Journal of materials Science & Technology 2004年第2期20卷 206-208页

作者： Xuyan XUE, Chunlei WANG and Weilie ZHONGSchool of Physics and Microelectronics, state key laboratory of crystal materials, shandong university, jinan 250100, china shandong Univ Sch Phys & Microelect State Key Lab Crystal Mat Jinan 250100 Peoples R China

The crystal and electronic structure of antiferroelectric squaric acid is studied using density functional theory method, and the exchange correlation effects are treated by the generalized approximation. In order to understand the ferroelectricity of H2SQ in the molecular plane and the antiferroelectricity in whole crystal, the density of states, charge density distribution and band structure are calculated. The result showed that O2p and C2p play important roles in the interactions between layers. The hybridizations of 02s-Hls and 02p-Hls are responsible for the tendency to ferroelectricity within each layer.

关键词： Antiferroelectricity Electronic structure Squaric acid

A first-principles study of dihydroazulene as a possible optical molecular switch

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Science china(Physics,Mechanics & Astronomy) 2011年第3期Mechanics & Astronomy) .卷 437-441页

作者： XIA CaiJuan1, LIU DeSheng2,3 & LIU HanChen1 1 School of Science, Xi’an Polytechnic university, Xi’an 710048, china 2 School of Physics, state key laboratory of crystal materials, shandong university, jinan 250100, china 3 Department of Physics, Jining university, Qufu 273155, china School of Science Xi’an Polytechnic University Xi’an China School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan China Department of Physics Jining University Qufu China

By applying nonequilibrium Green's function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of the dihydroazulene optical molecular switch. Three kinds of adsorption sites including the hollow, bridge and top sites are studied. The two forms of this molecule, namely the open form and the closed form, can reversibly switch from each other upon photoexcitation. Their transmission spectra are remarkably distinctive. Theoretical results show that the current of the closed form is always significantly larger than that of the open form for all three adsorption sites, which promises this system as possibly one of the good candidates for optical switches due to its unique advantage, and which may have some potential applications in the future molecular circuit.

关键词： molecular switch nonequilibrium Green’s function electronic transport density functional theory

SOS Calculation of Nonlinear Optical Propertiesof Synthesized ASPBPh_4

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Chemical Research in Chinese Universities 2001年第2期17卷 207-211页

作者： ZHAO Xian, TIAN Yu-peng, ZHOU Yu-fang and JIANG Min-hua (state key laboratory of crystal materials, shandong university, jinan 250100, P. R. china) LIU Yong-jun and HU Hai-quan (Institute of Theoretical Chemistry, shandong university, jinan 250100) 山东大学晶体材料国家重点实验室山东济南 250100 山东大学山东济南 250100

The two-photon absorption induced lasing spectrum shows that the synthesized ASPBPh4, trans-4- [p- (N-methyl-N- (hydroxyethyl)amino) styryl]-N-methylpyridinium, has a distinct ef- ficiency of laser frequency up-conversion. This nonlinear optical property of such a kind of com- pounds is related to two-photon absorption (TPA). In our work, we used the intermediate ne- glect of differential overlap (INDO) plus single-excitation configuration interaction (SCI) method to get the basic properties of the molecule, and calculated the second hyperpolarizability and the cross section of two-photon absorption by means of sum-over-state (SOS) expression. The rela- tionship between the structure and the properties is discussed.

关键词： Two-photon absorption Semiempirical method Sum-over-state

Lattice Effects and Irreversible Magnetoresistance in Gd Doped La-Ca-Mn-O

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Journal of materials Science & Technology 2002年第6期18卷 509-512页

作者： Baoxin HUANG, Yihua LIU, Ruzhen ZHANG, Chengjian WANG, Gang JI and Liangmo MEIDepartment of Physics and state key laboratory of crystal materials, shandong university, jinan, 250100, china shandong Univ Dept Phys Jinan 250100 Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

The Gd substituting effects for La in La0.67Ca0.33MnO3 has been studied. With increasing the substituting amount of Gd, the phase transition temperature of metal-isolator for the samples decreases, the corresponding peak resistivity increases, the Curie temperature decreases monotonically. The substitution of La-Ca-Mn-O with 11% Gd for La improved the magnetoresistance ratio by an order of magnitude. The effects of substituting Gd can be explained in terms of the lattice effects. An irreversible MR behaviour was observed in Gd-substituting compounds. This effect became marked when the substituting amount of Gd was greater than 7%. A maximum irreversible increment of MR ratio as large as 91% was obtained when Gd substituting amount was 11%.

关键词： Manganese perovskites Colossal magnetoresistance Lattice effect Irreversible magnetoresistance

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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Science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3, HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. state key laboratory of crystal materials, shandong university, jinan 250100, china 2. School of Information Science and Engineering, shandong university, jinan 250100, china 3. Department of Chemical Engineering, Light Industry College of shandong, jinan 250100, china 4. key laboratory of Biomedical Photonics, Ministry of Education, Huazhong university of Science and Technology, Wuhan 430074, china state key laboratory of crystal materials Shandong University Jinan China School of Information Science and Engineering Shandong University Jinan China Department of Chemical Engineering Light Industry College of Shandong Jinan China key laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 46.2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Electron transport properties of boron-doped capped-carbon-nanotube-based molecular junctions

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Science Bulletin 2010年第36期55卷 4104-4107页

作者： ZHAO Peng1 & LIU DeSheng2 1 School of Science, university of jinan, jinan 250022, china 2 School of Physics, state key laboratory of crystal materials, shandong university, jinan 250100, china School of Science University of Jinan Jinan China School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan China

Using the Landauer formalism that combines both the non-equilibrium Green’s function and first-principles density functional theory, the electron transport properties of a one-dimensional molecular junction based on capped carbon nanotubes with boron doping at various sites are investigated. The results show that the electron transport properties are strongly dependent on the boron-doping site. Negative differential resistance behavior can be observed when boron-atom dopants are present in the tip region.

关键词： carbon nanotube doping non-equilibrium Green’s function density functional theory

Theoretical Study on the Structure and Vibrational Spectra for 4-methyl-3-penten-2-one

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Chinese Chemical Letters 1999年第10期10卷 835-838页

作者： Dong Mei DU Ai Ping FU Zheng Yu ZHOU (Department of Chemistry. Qufu Normal university, shandong, Qufu 273165 2 state key laboratory of crystal materials. shandong university, shandong, jinan 250100) Department of Chemistry Qufu Normal University Shandong Qufu 273165 China state key lab. of crystal materials Shandong University Shandong Jinan 250100 China

Density functional theory BLYP (using Becke's and Lee-Yang-Parr's correlation functionals), nb initio Hartree-Fock (HF) and hybrid DFT/HF B3LYP calculations were carried out to study the structure and vibrational spectra of 4-methyl-3-penten-2-one. The BLYP/6-31G* and scaled HF/6-31G* frequencies correspond well with each other and with available experimental assignment of the functional vibrational modes.

关键词： density functional theory vibrational spectra 4-methyl-3-penten-2-one

Theory Study on Structures and Vibrational Frequencies of Pyruvic acid

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Chinese Chemical Letters 2000年第5期11卷 447-450页

作者： Dong Met DU Ai Ping FU Zheng Yu ZHOU (Department of Chemistry. Qufu Normal university. shandong. Qufu 273165 state key laboratory crystal materials shandong university.shandong. jinan 250100) Department of Chemistry Qufu Normal University Shandong Qufu 273165 China state key lab. crystal Mat. S. Shandong Jinan 250100 China

Density functional theory BLYP (using Becke's and Lee-Yang-Pars's correlation functionals), ab initio Hartree-Fock (HF) and hybrid DFT/HF B3LYP calculations were carried out to study the structure and vibrational spectra of pyruvic acid. The scaled B3LYP/6-31G* frequencies correspond well with available experimental assignment of the functional vibrational modes and the mean absolut devation is only 12.3cm^(-1).

关键词： Density functional theory vibrational spectra pyruvic acid