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Investigation of Concrete Distortion with Real-time Holographic Method

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Semiconductor Photonics and Technology 2002年第2期8卷 106-110页

作者： LUXiao－xu zhangli－xiang 等 LaserReserchInstitute KunmingUniv.ofSci.nadTechn.Kunming650051CHN FacultyofArchitect.Eng. KunmingUnivofSci.andTech.Kunming650051CHN

In order to find the relationships between the distortion rule ofthe concrete and its surrounding stress field, a real-time opticalholographic setup is used to record the distribution and thevariation of the samples, the waveforms of ultrasonic emissionstimulated by the micro-cracks are recorded by a transient automaticwaveform recorder to determine the time location and intensity of theactions of micro-cracks. The experiment results are worth *** method provides a useful experimental approach to study thebrittleness materials.

关键词： Real-time holography distortion concrete

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贯流式水轮机三维非定常流DES数值模拟

机械与电子 2014年第6期32卷 48-51页

作者：欧阳振宇张立翔昆明理工大学土木工程学院云南昆明650500

以某水电站为研究对象,建立包含贯流式水轮机的全流道数值模型,基于不可压缩瞬态N-S方程,进行了三维非定常流研究。将全流道定常计算的结果作为初始流场,应用分离涡模型(DES)和滑移网格技术,进行了水轮机动静干扰的非定常湍流数值模拟,... 详细信息

以某水电站为研究对象,建立包含贯流式水轮机的全流道数值模型,基于不可压缩瞬态N-S方程,进行了三维非定常流研究。将全流道定常计算的结果作为初始流场,应用分离涡模型(DES)和滑移网格技术,进行了水轮机动静干扰的非定常湍流数值模拟,得到了全流场的瞬时压力分布和湍动粘度分布,转轮室进出口处的瞬时涡量分布,捕捉到水轮机转轮室进出口处复杂的三维动态涡结构。研究工作对于探讨水轮机涡激振动形成的机理具有一定的参考意义。

关键词：贯流式水轮机计算流体动力学三维非定常湍流分离涡模拟

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao xiang Feng Gao Yu-Gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi Xu Junqiu Jia Rui Mao xiang Cao Yun Xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

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