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Journal of Materials Science & Technology 2023年第35期166卷 113-122页

作者： Z.G.Tai G.T.Sun X.h.Zhang X.B.Yang T.Wang Z.Y.Fang Q.Ye L.C.Jia h.Q.Wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China School of Materials Science and Engineering Shaanxi Normal UniversityXi’an 710119China

To suppress the inner charge recombination and inject vast electrons,CdTe nanocrystals are embedded into ultrathin ZnIn_(2)S_(4) nanosheets to construct ZnIn_(2)S_(4)/CdTe heterostructures,where the nanocrystals are generated by a laser irradiation *** optimal ZnIn_(2)S_(4)/CdTe heterojunction exhibits an excellent catalytic activity of 24.3 mmol/h/g,which is relatively high among the ZnIn_(2)S_(4)-based photocatalysts with-out noble *** enhancement is ascribed to a win-win mechanism of nanoscale heterojunctions and sulfur *** strong electron coupling effect,which is verified by density functional the-ory(DFT)calculations,impels the photo-generated electrons transfer from CdTe to ZnIn_(2)S_(4),boosting the charge ***,the sulfur vacancies existing in ZnIn_(2)S_(4) can capture photoelectrons and act as active sites,facilitating the h_(2) generation *** addition,the ZnIn_(2)S_(4) base and the ZnIn_(2)S_(4)/CdTe heterojunction also possess an evident photothermal effect and renewable cycle phenomena,enhancing the photocatalytic *** research provides new insights into the regulation of charge transfer through embedding nanocrystals.

关键词： Photocatalysis hydrogen evolution Laser irradiation heterostructure Sulfur vacancies

Continuous Spectrum of Trigonometric Rosen-Morse and Eckart Potentials from Free Particle Spectrum

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Communications in Theoretical Physics 2011年第6期55卷 965-968页

作者： h.Panahi h.Pouraramt Department of Physics University of GuilanP.O.Box 41335-1914RashtIran

The shape invariant symmetry of the Trigonometric Rosen-Morse and Eckart potentials has been studied through realization of so（3） and so（2, 1） Lie algebras respectively. In this work, by using the free particle eigenfunction, we obtain continuous spectrum of these potentials by means of their shape invariance symmetry in an algebraic method.

关键词： Trigonometric Rosen-Morse and Eckart potentials supersymmetric quantum mechanics shapeinvariant symmetry so(3) so(2 1)

Comparison of Impact Properties for Carbon and Low Alloy Steels

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Journal of Materials Science & Technology 2011年第10期27卷 931-936页

作者： O.h.Ibrahim Metallurgy Dept. Nuclear Research CentreAtomic Energy Authority

The impact properties of hot rolled carbon steel （used for the manufacture of reinforcement steel bars） and the quenched ＆ tempered （Q＆T） low alloy steel （used in the pressure vessel industry） were determined. The microstructure of the hot rolled carbon steel contained ferrite/pearlite phases, while that of the quenched and tempered low alloy steel contained bainite structure. Impact properties were determined for both steels by instrumented impact testing at temperatures between -150 and 200℃. The impact properties comprised total impact energy, ductile to brittle transition temperature, crack initiation and propagation energy, brittleness transition temperature and cleavage fracture stress. The Q＆T low alloy steel displayed much higher resistance to ductile fracture at high test temperatures, while its resistance to brittle fracture at low test temperatures was a little higher than that of the hot rolled carbon steel. The results were discussed in relation to the difference in the chemical composition and microstructure for the two steels.

关键词： Ferritic/pearlitic steel Bainitic steel Impact properties

A STABILITY ThEOREM FOR CONSTRAINED OPTIMAL CONTROL PROBLEMS

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Journal of Computational Mathematics 2004年第5期22卷 633-640页

作者： M.h.Farag DepartmentofMathematicsandComputerScienceFacultyofEducation lbriSultanateofOman

This paper presents the stability of difference approximations of an optimal control problem for a quasilinear parabolic equation with controls in the coefficients, boundary conditions and additional restrictions. The optimal control problem has been convered to one of the optimization problem using a penalty function technique. The difference approximations problem for the considered problem is obtained. The estimations of stability of the solution of difference approximations problem are proved. The stability estimation of the solution of difference approximations problem by the controls is obtained.

关键词： Finite difference method Penalty function methods Quasilinear Parabolic equations Stability estimations

Solvability of a class of PT-symmetric non-hermitian hamiltonians：Bethe ansatz method

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Chinese Physics B 2017年第6期26卷 14-21页

作者： M Baradaran h Panahi Department of Physics University of Guilan Rasht 41635-1914Iran

We use the Bethe ansatz method to investigate the Schrdinger equation for a class of PT-symmetric non-hermitian hamiltonians. Elementary exact solutions for the eigenvalues and the corresponding wave functions are obtained in terms of the roots of a set of algebraic equations. Also, it is shown that the problems possess sl（2） hidden symmetry and then the exact solutions of the problems are obtained by employing the representation theory of sl（2） Lie algebra. It is found that the results of the two methods are the same.

关键词： PT-symmetry Bethe ansatz method Lie algebraic approach quasi-exactly solvable

Piezoelectric polarization and quantum size effects on the vertical transport in AlGaN/GaN resonant tunneling diodes

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Chinese Physics B 2016年第6期25卷 483-488页

作者： Dakhlaoui h Almansour S Department of Physics College of Science for GirlsUniversity of Dammam (UOD)

In this work,the electronic properties of resonant tunneling diodes（RTDs） based on GaN-AlxGa（1-x）N double barriers are investigated by using the non-equilibrium Green functions formalism（NEG）.These materials each present a wide conduction band discontinuity and a strong internal piezoelectric field,which greatly affect the electronic transport *** electronic density,the transmission coefficient,and the current–voltage characteristics are computed with considering the spontaneous and piezoelectric *** influence of the quantum size on the transmission coefficient is analyzed by varying GaN quantum well thickness,AlxGa1-xN width,and the aluminum concentration *** results show that the transmission coefficient more strongly depends on the thickness of the quantum well than the barrier;it exhibits a series of resonant peaks and valleys as the quantum well width *** addition,it is found that the negative differential resistance（NDR） in the current–voltage（I–V） characteristic strongly depends on aluminum concentration *** is shown that the peak-to-valley ratio（PVR） increases with xAlvalue *** findings open the door for developing vertical transport nitrides-based ISB devices such as Thz lasers and detectors.

关键词： nitride semiconductor resonant tunneling diode current density

Bleomycin诱导凋亡细胞histone h1.2从核向线粒体的转移

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Bleomycin诱导凋亡细胞histone H1.2从核向线粒体的转移

ThE FINITE ELEMENT METhOD FOR SEMILINEARPARABOLIC EQUATIONS WITh DISCONTINUOUSCOEFFICIENTS

中华口腔医学会第七届全国口腔病理学术会议

作者： hirohiko Okamura kaya Yoshida Lihong Qiu Bruna Rabelo Amorim Tatsuji haneji University of Tokushima Graduate School Kuramoto Tokushima 770-8504 Japan

Bleomycin是一种水溶性抗生素,被用来治疗癌症利淋巴瘤。该抗生素能与细胞表面受体结合,形成吞饮小泡而被移入细胞中,我们的实验已经证明bleomycin and peplomycin,能诱导SCCTF细胞DNA单双链碎片的形成,线粒体膜破坏,从而导致细胞凋亡...

Bleomycin是一种水溶性抗生素,被用来治疗癌症利淋巴瘤。该抗生素能与细胞表面受体结合,形成吞饮小泡而被移入细胞中,我们的实验已经证明bleomycin and peplomycin,能诱导SCCTF细胞DNA单双链碎片的形成,线粒体膜破坏,从而导致细胞凋亡。可是,该凋亡发生的信号传导途径还不很清楚,本研究检测bleomycin处理的鳞癌细胞中细胞色素C

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Journal of Computational Mathematics 1999年第2期17卷 191-198页

作者： Feng, h Shen, LJ Shenzhen Univ Normal Coll Shenzhen 518060 Peoples R China Inst Appl Phys & Computat Math Lab Computat Phys Beijing 100088 Peoples R China

In this paper we investigate the existence, uniqueness and regularity of the solution of semilinear parabolic equations with coefficients that are discontinuous across the interface, some prior estimates are obtained. A net shape of the finite elements around the singular points was designed in [7] to solve the linear elliptic problems, by means of that net, we prove that the approximate solution has the same convergence rate as that without singularity.

关键词： finite element semilinear parabolic equation discontinuous coefficients

AN OUTLINE OF ThE VARIETIES OF ThE SECOND-ORDER SYSTEMS SCIENCES

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Journal of Systems Science and Systems Engineering 2017年第3期26卷 383-412页

作者： Karl h. Muller International Academy for Systems Science and Cybernetics Steinbeis Transfer Center New Cybernetics Vienna Austria

The systems sciences are based on a universal language of systems which can be used within most academic disciplines in their endeavors for exploring the world. Currently, systems sciences cover a wide variety of different approaches like complex adaptive systems, resilient systems or systems engineering. One of the future extensions of the systems sciences comes through the applications of second-order systems science as a new field of reflexive studies on first-order systems science. This article provides a general background on the relations of first-order science and second-order science in general and then goes on to sketch a basic outline for the second-order systems sciences and their potentials for quality control and for innovations for the first-order systems sciences.

关键词： Optimization

Investigation of optoelectronic properties of pure and Co substituted α-Al_2O_3 by hubbard and modified Becke–Johnson exchange potentials

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Chinese Physics B 2015年第9期24卷 430-435页

作者： h.A.Rahnamaye Aliabad Department of Physics Hakim Sabzevari University

Advanced GGA ＋ U（hubbard） and modified Becke–Johnson（mBJ） techniques are used for the calculation of the structural, electronic, and optical parameters of α-Al2-x CoxO3（x = 0.0, 0.167） compounds. The direct band gaps calculated by GGA and m BJ for pure alumina are 6.3 eV and 8.5 eV, respectively. The m BJ approximation provides results very close to the experimental one（8.7 eV）. The substitution of Al with Co reduces the band gap of alumina. The wide and direct band gap of the doped alumina predicts that it can efficiently be used in optoelectronic devices. The optical properties of the compounds like dielectric functions and energy loss function are also calculated. The rhombohedral structure of theα-Al2-x CoxO3（x = 0.0, 0.167） compounds reveal the birefringence properties.

关键词： density functional theory hubbard U modified Becke–Johnson exchange potential optoelectronic properties