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Preparation and Optical Properties of SnO2／SiO2 Nanocomposite

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Chinese Physics Letters 2004年第7期21卷 1374-1376页

作者： FENGYi-Si YAORi-Sheng zhangli-de SchoolofChemicalEngineering HefeiUniversityofTechnologyAnhui230009 InstituteofSolidStatePhysics ChineseAcademyofSciencesPO1129BoxHefei230031

SnO2/SiO2 nanocomposites have been prepared by the soaking-thermal-decomposing method, tin oxide nanoparticles are uniformly dispersed in the mesopores of silica. The optical absorption edge of the obtained nanocomposite presents a redshift compared with bulk tin oxide. With the increasing annealing temperature during the procedure of the sample preparation, the optical absorption edge of the sample moves to shorter wavelength (blueshift). These optical properties can be ascribed to the amorphous structure and band defects of surface layers of the tin oxide nanoparticles.

关键词： Nanocomposites

Enhancing forecasting of current-carrying performance through spatial frequency analysis of interface morphology

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Science China Technological Sciences 2025年

作者： Nian YIN Zishuai WU zhangli HOU Yiwei ZHANG Zhinan ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University School of Mechanical Engineering Shanghai Jiao Tong University

Electrical contact interfaces, integral to devices such as connectors, switches, and conductive slip rings, play a crucial role in determining current-carrying capabilities. This study adopts spatial frequency analysis to assess the currentcarrying performance of interfaces based on their morphological characteristics. Initially, rough surfaces with various parameters, including the cutoff frequency(N), the spectral index(β), and the gain factor(A), were generated using spatial frequency methods, followed by current-carrying simulations. The findings reveal that the characteristic parameters derived from spatial frequency methods exhibit a significantly stronger correlation with current-carrying performance than traditional roughness metrics. To enhance the practical applicability of this research, a physical-informed machine learning approach for rough surface features extraction was developed, demonstrating high predictive parameter identification accuracy for the three parameters. Overall, this paper introduces a tribo-informatics approach for analyzing and extracting rough surface features that considers the curvature characteristics of contact points. This approach holds significant potential for evaluating the processing state of current-carrying interfaces, selecting high-quality surfaces, and forecasting current-carrying performances.

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Oligodendroglial heterogeneity in health,disease,and recovery:deeper insights into myelin dynamics

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Neural Regeneration Research 2025年第11期20卷 3179-3192页

作者： Pieter-Jan Serneels Julie D.de Schutter Lies de Groef Lieve Moons Steven Bergmans KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionNeural Circuit Development&Regeneration Research GroupLeuvenBelgium KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionCellular Communication&Neurodegeneration Research GroupLeuvenBelgium

decades of research asserted that the oligodendroglial lineage comprises two cell types:oligodendrocyte precursor cells and ***,recent studies employing single-cell RNA sequencing techniques have uncovered novel cell states,prompting a revision of the existing *** forward,the oligodendroglial lineage should be delineated into five distinct cell states:oligodendrocyte precursor cells,committed oligodendrocyte precursor cells,newly formed oligodendrocytes,myelin-forming oligodendrocytes,and mature *** new classification system enables a deeper understanding of the oligodendroglia in both physiological and pathological *** this uniform terminology will facilitate comparison and integration of data across ***,including the consolidation of findings from various demyelinating models,is essential to better understand the pathogenesis of demyelinating ***,comparing injury models across species with varying regenerative capacities can provide insights that may lead to new therapeutic strategies to overcome remyelination ***,by standardizing terminology and synthesizing data from diverse studies across different animal models,we can enhance our understanding of myelin pathology in central nervous system disorders such as multiple sclerosis,Alzheimer's disease,and amyotrophic lateral sclerosis,all of which involve oligodendroglial and myelin dysfunction.

关键词： animal models demyelination fish mammals multiple sclerosis myelin neurodegeneration oligodendrocytes oligodendroglial lineage remyelination

Synthesis and Structure of L-Aspartato- nickel(II) Complex with Benzimidazole

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Chinese Journal of Structural Chemistry 2004年第4期23卷 386-390页

作者： zhangli DAIZhi-Yuan departmentofFoodScience HangzhouInstituteofCommerceHangzhou310012China

The title complex Ni(C4H5NO4)(C7H6N2)31.75(H2O) (C25H26.5N7NiO5.75, Mr = 575.74) has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal of this chiral complex belongs to monoclinic, space group P21 with a = 13.208(1), b = 10.741(1), c = 19.398(1) ? b = 104.39(1)o, V = 2665.8(4) 3, Z = 4, Dc = 1.435 g/cm3, m(MoKa) = 0.780 mm-1 and F(000) = 1198. The final R = 0.0504 and wR = 0.1267 for 9159 observed reflections (I > 2s(I)), and R = 0.065 and wR = 0.1299 for 11006 independent reflections. The complex assumes a distorted octa- hedral coordinate geometry formed by one aspartate dianion and three benzimidazole ligands. The aspartate chelates to the Ni atom as a tridentate ligand. The lattice water molecules are hydrogen- bonded to the Ni complex molecule.

关键词： Ni(II) complex aspartate crystal structure synthesis benzimidazole

Polar Oscillation of Interface and Surface Optical Phonons in Free-Standing Cylindrical Quantum-Well Wires

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Communications in Theoretical Physics 2004年第3X期42卷 459-466页

作者： zhangli departmentofMechanismandelectron PanyuPolytechnicCollegePanyu511483China

Under dielectric continuum approximation, interface optical (IO) and surface optical (SO) phonon modes aswell as the corresponding Frohlich electron-phonon interaction Hamiltonian in a free-standing cylindrical quantum-wellwire (Q WW) are derived and studied. Numerical calculations on GaAs/AlxGa1-xAs cylindrical QWW are *** reveal that there are two branches of IO phonon modes and one branch of SO phonon mode, and the dispersionfrequencies ofIO or SO phonon modes sensitively depend on the Al mole fraction x in Alx Ga1-x As material and the wave-vector in z direction, kz. With the increasing of κz and quantum number m, the frequency of each IO mode approaches oneof the two frequency values of the single GaAs/Alx Ga1-xAs heterostructure, and the electrostatic potential distributionof the phonon mode tends to be more and more localized at a certain interface or surface, meanwhile, the couplingbetween the electron-IO and -SO phonons becomes weaker.

关键词：光子模型圆柱形量子阱线量子点量子器件表面界面量子数

Vibration Spectrums of Polar Interface Optical Phonons in GaAs／AlAs Cylindrical Quantum Dots

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Communications in Theoretical Physics 2005年第2期43卷 333-336页

作者： zhangli SchoolofPhysics PekingUniversityBeijing100871China／／DepartmentofMechanismandElectronicsPanyuPolytechnicCollegePanyu511483China

The dispersions of the top interface optical phonons and the side interface optical phonons in cylindrical quantum dots are solved by using the dielectric continuum model. Our calculation mainly focuses on the frequency dependence of the IO phonon modes on the wave-vector and quantum number in the cylindrical quantum dot *** reveal that the frequency of top interface optical phonon sensitively depends on the discrete wave-vector in z direction and the azimuthal quantum number, while that of the side interface optical phonon mode depends on the radial and azimuthal quantum numbers. These features are obviously different from those in quantum well, quantum well wire,and spherical quantum dot systems. The limited frequencies of interface optical modes for the large wave-vector or quantum number approach two certain constant values, and the math and physical reasons for this feature have been explained reasonably.

关键词： phonon modes vibration spectrums cylindrical quantum dots

NUMERICAL SIMULATION OF TURBULENT SPOTS IN INCLINED OPEN-CHANNEL FLOW

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Journal of Hydrodynamics 2005年第2期17卷 179-185页

作者： zhangli TANGdeng-bin CollegeofAerospaceEngineering NanjingUniversityofAeronauticsandAstronauticsNanjing210016China

The generation and evolution of turbulent spots in the open-channel flow are simulated numerically by using the Navier-Stokes equations. An effective numerical method with high accuracy and high resolution is developed. The fourth-order time splitting methods with high accuracy is proposed. Three-dimensional coupling difference methods are presented for the spatial discretization of the Poisson equation of pressure and Hemholtz equations of velocity, therefore, the fourth-order three-dimensional coupling central difference schemes are constituted. The fourth-order explicit upwind-biased compact difference schemes are designed to overcome the difficulty for the general higher-order central difference scheme which is inadaptable in the boundary neighborhood. The iterative algorithm and overall time marching is used to enhance efficiency. The method is applied in the numerical simulation of turbulent spots at various complex boundary conditions and flow domains. The generation and the developing process of turbulent spots are given, and the basic characteristics of turbulent spots are shown by simulating the evolution of the wall pulse in inclined open-channel flow.

关键词： turbulent spot Navier-Stokes equation numerical simulation three-dimensional coupling difference scheme wall pulse

Studies on the Second-Order Nonlinear Optical Properties of Parabolic andSemi-parabolic Quantum Wells with Applied Electric Fields

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Communications in Theoretical Physics 2004年第5期41卷 761-766页

作者： zhangli XIEHong-Jing departmentofMechanicsandelectronics PanyuPolytechniqueCollegePanyu511483China departmentofPhysics GuihuagangCampusGuangzhouUniversityGuangzhou510405China

Within the framework of compact density matrix approach and iterative procedure, a detailed procedure for the calculation of the second-harmonic generation (SHG)susceptibility tensor is given in the electric-field-biased parabolic and semi-parabolic quantum wells (QWs). The simple analytical formula for the SHG susceptibility in the systems is also deduced. Numerical results on typical AlGaAs/GaAs materials show that, for the same effective width,the SHG susceptibility in semi-parabolic QW is larger than that in parabolic QW due to the self-asymmetry of the semiparabolic QW, and the applied electric field can make the SHG susceptibilities in both systems enhance ***, the SHG susceptibility is also related to the parabolic confinement frequency and the relaxation rate of the systems.

关键词： parabolic and semi-parabolic quantum wells electric field second-harmonic generation density matrix approach

Modeling of damage in materials during hot deformation based on the Zener-Hollomon parameter

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Rare Metals 2004年第1期23卷 88-92页

作者： LIUXuefeng WANGLingyun zhangli SchoolofMaterialsScienceandengineering UniversityofScienceandTechnologyBeijing.Beijing100083China CollegeofMaterialsScienceandengineering ChongqingUniversityChongqing400044.China Library ChongqingInstituteofTechnologyChongqing400050.China

By introducing the Zener-Hollomon parameter, which synthetically considersthe influence of deformation temperature and strain rate into damage mechanics, a damage evolutionmodel was developed to simulate the damage evolution of metallic materials during hot *** errors between the prediction damage values and the experimental ones are within 6%.

关键词： metallic materials damage evolution hot deformation zener-hollomonparameter