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Chinese Physics B 2010年第4期19卷 42-49页

作者：范洪义 department of material Science and Engineering University of Science and Technology of China

Using the Weyl ordering of operators expansion formula （Hong-Yi Fan, J. Phys.A 25 （1992） 3443） this paper finds a kind of two-fold integration transformation about the Wigner operator △（ q＇,p） q-number transform） in phase space quantum mechanics,∫∫∞-∞dp＇dq＇/π △（q＇,p＇）e-2i（ p-p＇）（ q-q＇）=δ（ p-P）δ（ q-Q）,∫∫∞-∞dqdpδ（p-P）δ（q-Q）e2i（p-p＇）（q-q＇）=△（q＇,p＇）,whereQ,P are the coordinate and momentum operators, respectively. We apply it to study mutual converting formulae among Q-P ordering, P-Q ordering and Weyl ordering of operators. In this way, the contents of phase space quantum mechanics can be enriched. The formula of the Weyl ordering of operators expansion and the technique of integration within the Weyl ordered product of operators are used in this discussion.

关键词： Wigner operator Weyl ordering two-fold integration transformation

Study of Quantitative Structure-retention Relationship for Substituted Phenols

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Chinese Journal of Structural Chemistry 2007年第7期26卷 855-859页

作者：柳红霞曾小兰刘红艳 department of material and Chemical Engineering Guilin Institute of Technology

Quantum chemistry parameters of 20 substituted phenols were computed at the 6- 31G＊ level using DFT method. Based on theoretical linear solvation energy theory, the correlation equation that can predict the retention index （Ri） was developed using structural parameters of 15 substituted phenols with experimental data as theoretical descriptors, and the conventional correlation coefficient （R^2） is 0.9885. The correlation degree of each independent variable in the model was validated by variance inflation factors （VIF） and t-test. Cross-validation indicates that the model possesses high predicting ability. The correlation and predicting ability of the Ri equation are both more advantageous than those based on orientating group index, connectivity index, and topological index method. In addition, RI values of 5 compounds without experimental data were predicted with the model.

关键词： substituted phenol linear solvation energy theory density functional theory (DFT) QSRR retention index (RI)

Asymmetric Ni/PVC Films for High-performance Electromagnetic Interference Shielding

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Chinese Journal of Polymer Science 2015年第6期33卷 899-907页

作者：张扬 Xiao-xia Fang 温变英 department of material Science and Engineering Beijing Technology and Business University

A novel asymmetric Ni/PVC film has been developed by solution casting method. The structure, electrical conductivity, electromagnetic interference （EMI） shielding, and impact resistance were investigated. The results showed that the Ni particles were asymmetrically distributed along the thickness direction in the film. The top surface resistivity increased with film thickness, while the bottom surface exhibited the different trend. EMI shielding effectiveness （SE） depended on formation of closed packed conductive Ni network, which was influenced by both Ni content and film thickness. A linear relationship was observed between EMI SE and film thickness. The films with lower Ni content showed the faster increasing rate of EMI SE with film thickness. Some of the films show appreciably high EMI SE （〉 40 dB）, indicating the promising application in EMI shielding field. Moreover, the films exhibit different impact performance under different impacting directions. All the experimental facts demonstrate that the asymmetric structure endows the film achieving high-performance EMI shielding function.

关键词： Asymmetric structure Electrical conductivity Electromagnetic interference shielding.

Simulation of scattering in dense medium by Monte Carlo method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第B8期6卷 155-157页

作者：刘涌宋晨路翁文剑杜丕一韩高荣 State Key Laboratory of Silicon material Science Department of Material Science and Engineering Zhejiang University

We present a Monte Carlo (MC) method to simulate the scattering for medium within randomly distributed particles, discuss the convergence of this method by varying the size parameter ka, volume parameter η and calculation parameter Ni, then compare this method with the classical iteration method with the same parameters. The calculation results showed that this method has good convergence and accords with the iteration method while consuming less CPU time. At the end of this paper, this method is used to discuss the visual light scatter in the c-Si/α-Si films.

关键词： Monte Carlo (MC) Iteration method Scattering

Effect of External Forced Flow and Boiling Film on Heat Transfer of AISI 4140 Steel Horizontal Rod During Direct Quenching

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Journal of Iron and Steel Research International 2011年第10期18卷 34-41页

作者： A H Meysami R Ghasemzadeh S H Seyedein M R Aboutalebi department of Metallurgy and material Engineering Golpayegan University Centre of Excellent for Advanced material and Processing School of Metallurgy and Material EngineeringIran University of Science and Technology

The effects of rod falling and moving, external flow field, boiling film and radiation were investigated on fluid flow and heat transfer of AISI 4140 steel horizontal rod during direct quenching by mathematical modeling. The flow field and heat transfer in quenching tank were simulated by computational fluid dynamics （CFD） method considering falling and moving of rods during process. Therefore, modeling of flow field was done by a fixed-mesh method for general moving objects equations, and then, energy equation was solved with a numerical approach so that effeet of boiling film heat flux was considered as a source term in energy equation for solid-liquid boundary. Simulated results were verified by comparing with published and experimental data and there was a good agreement between them. Also, the effects of external forced flow and film boiling were investigated on heat flux output, temperature distribution and heat transfer coefficient of rod. Also simulated results determined optimum quenching time for this process.

关键词： direct quenching AISI 4140 moving object heat transfer modeling

The Statistical Properties of a New Type of Photon-Subtracted Squeezed Coherent State

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Chinese Physics Letters 2012年第5期29卷 14-17页

作者： ZHOU Jun SONG Jun YUAN Hao ZHANG Bo department of material and Chemical Engineering West Anhui UniversityLu’an 237012 department of material Science and Engineering University of Science and Technology of ChinaHefei 230026

We construct a new type of photon-subtracted squeezed coherent state (PSSCS) based on a squeezed coherent state (SCS) [***.A 220 (1996)81].Some of the statistical properties of the PSSCS,such as Mandel's Q parameter a... 详细信息

关键词： coherent photon squeezed

A Novel Technique for Preparation of Electrically Conductive ABS/Cu Polymeric Gradient Composites

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Journal of Wuhan University of Technology(materials Science) 2013年第5期28卷 1003-1007页

作者：宦春花温变英 department of material Science and Engineering School of Material and Mechanical EngineeringBeijing Technology and Business University

A novel technique for preparing functionally gradient electrically conductive polymeric composites was developed by using of solution casting technique on the principle of Stokes＇ law. Acrylonitrile- butadiene-styrene/Cu （ABS/Cu） gradient polymeric composites were prepared successfully using this technique. The gradient structures, electrically conductive performance and mechanical properties of the ABS/Cu composites were investigated. Optical microscope observation shows that the gradient distribution of Cu particles in ABS matrix was formed along their thickness-direction. The electrically conductive testing results indicate that the order of magnitude of surface resistivity was kept in 10^15 Ω at ABS rich side, while that declined to 10^5 Ω at Cu particles rich side, and the percolation threshold was in the range of 2.82 vo1%- 4.74 vol% Cu content at Cu particles rich side. Mechanical test shows that the tensile strength reduced insignificantly as the content of Cu increases owing to the gradient distribution.

关键词： electrically conductive composite functionally gradient materials Stokes' law solution casting ABS Cu

The Fresnel-Weyl complementary transformation

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Chinese Physics B 2012年第10期21卷 70-72页

作者：谢传梅范洪义 College of Physics&material Science Anhui University department of material Science and Engineering University of Science and Technology of China

Based on the newly developed coherent-entangled state representation,we propose the so-called Fresnel-Weyl complementary transformation *** new operator plays the roles of both Fresnel transformation（for（a 1 a 2）/√ 2） and the Weyl transformation（for（a 1 ＋ a 2）/√ 2）.Physically,（a 1 a 2）/√ 2 and（a 1 ＋ a 2）/√ 2 could be a symmetric beamsplitter＇s two output fields for the incoming fields a 1 and a *** show that the two transformations are concisely expressed in the coherent-entangled state representation as a projective operator in the integration form.

关键词： coherent-entangled state representation Fresnel-Weyl complementary transformation beamsplitter

PHOTOCOPOLYMERIZATION OF MALEIC ANHYDRIDE AND VINYL ACETATE IN TETRAHYDROFURAN~*

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Chinese Journal of Polymer Science 1991年第4期9卷 358-362页

作者：李小放李善君秦安慰于同隐 department of material Science Fudan University Shanghai Department of ChemistryShandong UniversityJinanChina department of material Science Fudan University Shanghai

The copolymerization of maleic anhydride and vinyl acetate in tetrahydrofuran was studied. Results show that the maximum copolymerization rate is in 0.6 mole fraction of maleic anhydride, indicating the involvement of maleic anhydride-tetrahydrofuran charge transfer complex in the chain initiation process. ESR study provides collateral evidence for the formation of maleic anhydride radical and tetrahydrofuran radical.

关键词： THF MA PHOTOCOPOLYMERIZATION OF MALEIC ANHYDRIDE AND VINYL ACETATE IN TETRAHYDROFURAN UV

Physical Simulation of Hot Deformation and Microstructural Evolution for 42CrMo4 Steel Prior to Direct Quenching

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Journal of Iron and Steel Research International 2009年第6期16卷 47-51页

作者： A H Meysami R Ghasemzadeh S H Seyedein M R Aboutalebi R Ebrahimi M Javidani department of material Science and Engineering Iran University of Science and Technology department of material Science and Engineering Sabzevar Tarbiat-Moallem University

Direct quenching and tempering （DQ-T） of hot rolled steel section has been widely used in steel mill for the sake of improvement of mechanical properties and energy saving. Temperature history and microstructural evolution during hot rolling plays a major role in the properties of direct quenched and tempered products. The mathematical and physical modeling of hot forming processes is becoming a very important tool for design and development of required products as well as predicting the microstructure and the properties of the components. These models were mostly used to predict austenite grain size （AGS）, dynamic, recta-dynamic and static recrystallization in the rods immediately after hot rolling and prior to DQ process. The hot compression tests were carried out on 42CrMo4 steel in the temperature range of 900-1 100 ℃ and the strain rate range of 0. 05-1 s^-1 in order to study the high tempera- ture softening behavior of the steel. For the exact prediction of flow stress, the effective stress-effective strain curves were obtained from experiments under various conditions. On the basis of experimental results, the dynamic recrystallization fraction （DRX）, AGS, hot deformation and activation energy behavior were investigated. It was found that the calculated results were in good agreement with the experimental flow stress and microstructure of the steel for different conditions of hot deformation.

关键词： 42CrMo4 steel hot compression test dynamic recrystallization hot deformation direct quenching physical simulation