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Electronic Correlation Effects on the Optical Properties of SiC,BeO and Boron Nitride Nanotubes and Monolayers

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Communications in Theoretical Physics 2015年第11期64卷 583-589页

作者： h.Rezania z.Aghaii Manesh Department of Physics Razi University

We present numerical calculation of the impact of electron-electron interaction on the behavior of density of states and optical properties of BeO,SiC and Boron-Nitride nanotubes and *** model hamiltonian is applied to describe the dynamics of electrons on the lattice structure of theses *** excitation spectrum of the system in the presence of local electronic interactions has been found using mean Seld *** find the band gap width in both optical absorption and density of states reduces with local hubbard electronic interaction *** absorption spectra exhibits the remarkable peaks,mainly owing to the divergence behavior of density of states and excitonic *** we compare optical absorption frequency behavior of BeO,SiC and Boron-Nitride nanotubes with each *** we investigate the optical properties of BeO and SiC sheets.A novel feature of optical conductivity of these structures is the decrease of frequency gap in the optical spectrum due to electronic interaction.

关键词： nanotube optical conductivity hubbard model

MATRIX INVESTIGATION ON ISAIChEV ORIENTATION RELATIONShIP

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Acta Metallurgica Sinica(English Letters) 1999年第2期12卷 185-190页

作者： Sheng, z.Q. Xiao, h. Nuclear Power Inst of China Chengdu China

By means of TEM technique the orientation relationships of cementite, precipitated from islands of granular bainite during tempering, with ferrite have been observed. By calculating the eigenvalues and eigenvectors of transformation matrix, Isaichev relationship has been analyzed. The results indicate that Isaichev relationship is indeed the sum of Kurdjumov-Sachs relationship and Pitsch relationship, so the viewpoint that the cementite with Isaichev relationship precipitates from austenite, instead of ferrite, was confirmed. Moreover, the matrix calculation shows that three reported orientation relationships among austenite, ferrite and cementite in pearlitic transformation cannot be simultaneously valid. (Edited author abstract) 4 Refs.

关键词： Carbides Crystal orientation Eigenvalues and eigenfunctions Nuclear reactors Pearlitic transformations Phase transitions

Curvature-induced noncommutativity of two different components of momentum for a particle on a hypersurface

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Communications in Theoretical Physics 2021年第2期73卷 73-77页

作者： z Li X Yang Q h Liu School for Theoretical Physics School of Physics and ElectronicsHunan UniversiyChangsha 410082China School of Materials Science and Engineering Guilin University of Electronic TechnologyGuilin541004China Synergetice Innovation Center for Quantum Efects and Applications(SICQEA) Hunan Normal UniversityChangsha 410081China

As a nonrelativistic particle constrained to remain on an(N−1)-dimensional((N≥2))hypersurface embedded in an N-dimensional Euclidean space,two different components pi and pj(i,j=1,2,3,...N)of the Cartesian momentum of the particle are not mutually commutative,and explicitly commutation relations[p^(^)_(i),p^(^)_(j)](≠0) depend on products of positions and momenta in uncontrollable *** generalized Dupin indicatrix of the hypersurface,a local analysis technique,is utilized to explore the dependence of the noncommutativity on the curvatures around a local point of the *** first finding is that the noncommutativity can be grouped into two categories;one is the product of a sectional curvature and the angular momentum,and another is the product of a principal curvature and the *** second finding is that,for a small circle lying a tangential plane covering the local point,the noncommutativity leads to a rotation operator and the amount of the rotation is an angle anholonomy;and along each of the normal sectional curves centering the given point the noncommutativity leads to a translation plus an additional rotation and the amount of the rotation is one half of the tangential angle change of the arc.

关键词： constrained motion quantization hypersurface Dirac brackets geometric momentum

Thermal Product of Type-E Fast Response Temperature Sensors

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Journal of Thermal Science 2010年第4期19卷 364-371页

作者： h.A.Mohammed h.Salleh M.z.Yusoff Antonio Campo Department of Mechanical Engineering College of EngineeringUniversiti Tenaga NasionalKm 7Jalan Kajang-Puchong43009 KajangSelangorMalaysia Department of Mechanical Engineering The University of Texas at San AntonioSan AntonioTX 78249USA

This paper provides practical data for thermal product values of different scratched temperature sensors that can be used for accurate transient heat transfer measurements under hypersonic flow *** effect of using different scratch techniques(abrasive papers and scalpel blades)to form the sensor's junction is *** was observed that the thermal product of a particular sensor depends on the Mach number,junction scratch technique, junction location and enthalpy *** was demonstrated that using different scratched technique would produce different thermal product values.

关键词： thermal product fast response temperature sensor hypersonic flow.

Acoustic Multi Emission Lens via Transformation Acoustics

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Chinese Physics Letters 2018年第10期35卷 49-53页

作者： h.Barati z.Basiri A.Abdolali Applied Electromagnetic Laboratory School of Electrical Engineering Iran University of Science and Technology

Based on transformation acoustic methodology, we propose an algorithm for designing acoustic non-resonant lens antenna, which is competent to generate multiple directive beams that are pointing at the desired *** with previous works, the present approach is capable of adjusting the directivity of each radiated beam individually, which is of the utmost importance in several acoustic applications such as in sonar systems. A linear transformation function is intentionally used for eliminating the inhomogeneity of the obtained materials and to pave the way towards more general acoustic patterns. Several numerical simulations are performed to show the capability of the proposed method in manipulating the acoustic waves. To authenticate the concept,a structure that can generate four beams with different directivities is realized with non-resonant meta-fluid bi-layered structure through effective medium theory.

关键词： Acoustic Multi Emission Lens via Transformation Acoustics

A DESIGN FOR ENVIRONMENT METhODOLOGY FOR EVALUATION AND IMPROVEMENT OF DERIVATIVE CONSUMER ELECTRONIC PRODUCT DEVELOPMENT

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Journal of Systems Science and Systems Engineering 2011年第3期20卷 260-274页

作者： Tzu-An ChIANG z.h.ChE Tung-Te WANG Department of Business Administration National Taipei College of Business Department of Industrial Engineering & Management National Taipei University of Technology

Increasing environmental awareness and stringent environmental regulations have motivated many companies to incorporate ecodesign into product development. To assist companies to address the challenge, this research presents a design for environment （DfE） methodology to evaluate and improve derivative consumer electronic product development using a back-propagation neural network （BPNN） model and a technique for order preference by similarity to ideal solution （TOPSIS） method. Based on use of a BPNN, the life cycle assessment （LCA） models are developed to estimate quantities of hazardous chemical substances and energy consumption for a derivative consumer electronic product throughout the product life cycle. A performance evaluation and improvement model for DfE is then devised based on the TOPSIS method to analyze the ecodesign performance and provide concrete improvement strategies. With the aforementioned analysis of environmental performance, an enterprise can profoundly understand and significantly enhance the relative DfE performance of a new product compared to the similar competitive products. Finally, we apply an optical mouse development project as a case to elaborate and demonstrate the effectiveness of the proposed methodology. These analytical results can let us understand the DfE performance ranking and acquire the maximum reduced quantity of each DfE criterion for each module of a new product. Meanwhile, to enhance the green competitiveness of the new product, we recommend that the engineers should decrease the area of the circuit board of the new product. In addition, the material of the USB cable for the new product should be switched from the PVC material to the PE material.

关键词： Back-propagation neural network TOPSIS design for environment ecodesign product development

Energy transport for ion acoustic waves in a spin polarized quantum plasma

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Communications in Theoretical Physics 2020年第1期72卷 124-129页

作者： M Ayub z Iqbal h A Shah G Murtaza Salam Chair Department of PhysicsG.C.UniversityKatchery RoadLahore 54000Pakistan Department of Physics G.C.UniversityKatchery RoadLahore 54000Pakistan Department of Physics Mirpur University of Science and TechnologyMirpur-10250(AJK)Pakistan

The separate spin evolution quantum hydrodynamics(SSE-QhD)model is used to investigate the energy behavior for ion acoustic waves in degenerate quantum *** results show that the energy flow speed decreases with spin polarization *** is also shown that it decreases with the increasing rate up to a certain range of wave number and then it goes to zero *** is observed that Bohm potential suppresses the energy flow *** is also noticed that the energy flow speed deviates from the group velocity even in the absence of Bohm potential ***,the contribution of of Bohm poential effect in spin polarized plasma reduces the extent of deviation.

关键词： spin polarization quantum plasma ion acoustic wave energy flow speed

Electromagnetic effects on anisotropic expansion-free fluid content

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Communications in Theoretical Physics 2023年第10期75卷 79-89页

作者： z Yousaf h Asad Bander Almutairi Adnan Malik Department of Mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan Department of Mathematics College of ScienceKing Saud UniversityP.O.Box 2455 Riyadh 11451Saudi Arabia School of Mathematical Sciences Zhejiang Normal UniversityJinhuaZhejiangChina

The major goal of this work is to find solutions of Einstein–Maxwell field equations for anisotropic,expansion-free,non-static,spherically distributed matter *** analytical models that highlight the major benefit of simplicity are shown and this makes it possible to use them as a toy model to illustrate how cavities ***,the transport equations,quasi-homologous constraints and the junction conditions are also evaluated along with their useful ***,the consequences of electric force on this system are summed up in the last section.

关键词： gravitation neutron stars modified gravity hydrodynamics voids

FINITE ELEMENT ANALYSIS FOR MICROSTRUCTURE EVOLUTION IN hOT FINIShING ROLLING OF STEEL STRIPS

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Acta Metallurgica Sinica(English Letters) 2007年第2期20卷 79-86页

作者： z.D. Qu S.h. zhang D.z. Li z.T. Wang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China College of Material Science and Engineering Taiyuan University of Science andTechnology Taiyuan 030024 China Shenyang Ligong University Shenyang 110168 China

A computer model that describes the evolution of microstructures during the hot finishing rolling of SS400 steel has been proposed. It has been found that the microstructure strongly depends on processing of materials and on their parameters, which affected the history of the thermomechanical variables, such as temperature, strain, and strain rate. To investigate the microstructural evolutions during the hot finishing rolling process, the rigid-thermoviscoplastic finite element method （FEM） has been combined with dynamic recrystallization, static recrystallization, and grain growth models. The simulation results show a good agreement with those from the prediction software online.

关键词： finite element method (FEM) finishing rolling microstructure evolution recrystallization