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天津职业大学学报 2004年第5期13卷 23-26页

作者：张金环康晓明宋志勇郝玉涛天津职业大学天津市300402

本文介绍了CAI课件在现代教学的必要性及作用,阐明了《电工技术》课件开发过程分为教学设计、脚本设计、课件制作、评价和修改等四个阶段。此课件现已应用于教学实践中,具有很好的实用性。

关键词：电工技术 CAI课件动画制作

Experimental Study of Air Layer Drag Reduction with Bottom Cavity for A Bulk Carrier Ship Model

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China Ocean Engineering 2019年第5期33卷 554-562页

作者： WU hao OU yong-peng Key Laboratory of High Performance Ship Technology (Wuhan University of Technology) Ministry of Education Wuhan 430063 China School of Transportation Wuhan University of Technology Wuhan 430063 China College of Naval Architecture and Ocean Engineering Naval University of Engineering Wuhan 430033 China

Air lubrication by means of a bottom cavity is a promising method for ship drag reduction. The characteristics of the bottom cavity are sensitive to the flow field around the ship hull and the effect of drag reduction, especially the depth of the bottom cavity. In this study, a ship model experiment of a bulk carrier is conducted in a towing tank using the method of air layer drag reduction (ALDR) with different bottom cavity depths. The shape of the air layer is observed, and the changes in resistance are measured. The model experiments produce results of approximately 20% for the total drag reduction at the ship design speed for a 25-mm cavity continuously supplied with air at Cq = 0.224 in calm water, and the air layer covers the whole cavity when the air flow rate is suitable. In a regular head wave, the air layer is easily broken and reduces the drag reduction rate in short waves, particularly when λ/Lw1 is close to one;however, it still has a good drag reduction effect in the long waves.

关键词： air layer drag reduction bulk carrier model test depth of cavity air layer shape

GC/MS Analysis of Fractional Extraction of Fusain from Tongting Bituminous Coal in CS_2

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Journal of China University of Mining and Technology 2006年第1期16卷 8-12页

作者： QIN zhi-hong JIANG Chun SUN hao ZONG zhi-min JIANG Bing WEI Xian-yong School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FTTB coal and clarain from Tongting bituminous (CTTB) coal was carried out. The results show that the kinds of small molecule components detected by GC/MS of FTTB are less than those of CTTB. Long-chain alkanes exist mostly in the extracts of fusain. Macromolecular networks are predominant in the FTTB coal mainly composed of inertinite in the coal petrography. The size of micropores in the FTTB coal is relatively small, and the development of micropores is relatively low. Thus the content of aromatic compounds with affinity for micropores is relative low in FTTB, while the content of long-chain alkanes with affinity for macromolecule networks is relatively high. Sub-components in exinite determine the distribution of long-chain alkanes extracted in the last stage. Odd-numbered carbon distribution appears when resin is most in exinite, while high carbon alkane distribution appears when exinite is dominant in cutinite. Small aromatic molecules are firstly packed in micropores, and exist in a free state after micropores are saturated.

关键词： coal fusain extraction fractional sample CS2 GC/MS

Numerical study on the dynamic fracture of explosively driven cylindrical shells

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Defence Technology（防务技术） 2023年第9期27卷 154-168页

作者： zhi-yong Yin Xiao-wei Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Advanced Research Institute of Multidisciplinary Sciences Beijing Institute of TechnologyBeijing100081China

Research on the expansion and fracture of explosively driven metal shells has been a key issue in weapon development and structural *** is important to study and predict the failure mode,fracture mechanism,and fragment distribution characteristics of explosively driven metal *** this study,we used the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method and the fluid-structure interaction method to perform a three-dimensional numerical simulation of the expansion and fracture of a metal cylindrical *** method combined the advantages of the FEM and SPH,avoiding system mass loss,energy loss,and element distortion;in addition,the proposed method had a good simulation effect on the interaction between detonation waves and the cylindrical *** simulated detonation wave propagation,shell damage morphology,and fragment velocity distribution were in good agreement with theoretical and experimental *** divided the fragments into three regions based on their shape *** analyzed the failure mode and formation process of fragments in different *** numerical results reproduced the phenomenon in which cracks initiated from the inner surface and extended to the outer surface of the cylindrical shell along the 45°or 135°shear *** addition,fragments composed of elements are identified,and the mass and characteristic lengths of typical fragments at a stable time are ***,the mass and size distribution characteristics of the fragments were explored,and the variation in the fitting results of the classical distribution function under different explosion pressures was ***,based on mathematical derivation,the distribution formula of fragment velocity was *** improved formula provided higher accuracy and could be used to analyze any metal cylindrical shells with different length-to-diameter ratios.

关键词： Metal cylindrical shell Shear failure Fragment distribution Numerical simulation Fragment velocity

Investigations on Left Hand Cut Contribution to Determination of κ（700） Pole

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Communications in Theoretical Physics 2007年第5期47卷 883-886页

作者： ZHOU zhi-yong Department of Physics Peking University Beijing 100871 China

The uncertainties of background contributions to J = 0 partial wave πK scattering phase shifts are carefully studied. We firstly point out that the circular cuts exhibit different characters in S1/1 and S3/2 waves. While the former contributes negatively to the scattering length parameter, the latter contributes positively, i.e., has a wrong sign. This fact indicates that short range force contribu tions to the phase shift are non-negligible in the exotic channel. Nevertheless, it is verified that the κ pole will be affected only slightly with respect to the theoretical uncertainty in estimating the left hand cut contributions.

关键词： πK scattering unitarity dispersion relations κ resonance

A simple and controllable nanostructure comprising non-conductive poly（vinylidene fluoride） and graphene nanosheets for supercapacitor

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Frontiers of Materials Science 2012年第2期6卷 149-159页

作者： Jing SUN Ling-hao HE Qiao-Ling Zhao Li-Fang CAI Rui SONG yong-Mei hao zhi MA WeiHUANG Key Lab of Surface and Interface Sciences of Henan Provincial Zhengzhou University of Light IndustryZhengzhou 450002China Shanghai Institute of Organic Chemistry Chinese Academy of SciencesShanghai 200032china College of Chemistry and Chemical Engineering Gracluate University of Chinese Academy of SciencesBeijing 100049China Laboratory of Advanced Polymer Materials Institute of Chemistry Chinese Academy of SciencesBeijing 100080China

An effective method was used to Ioidal suspensions of highly reduced graphene produce stable and homogeneous coloxide （RGO） in N,N-dimethylformamide （DMF） without the assistance of dispersing agents. According to the results of general characterization, relatively pure graphene sheets with the morphology of single layer or few-layer structure were obtained. Then nanocomposite powders of RGO and poly （vinylidene fluoride）（PVDF） were prepared by vacuum filtration of the mixed dispersions of both components. The nanocomposites exhibit a high-frequency capacitative response with small equivalent series resistance （ESR） at 0.4Q, a nearly rectangular cyclic voltammogram and possess a rapid current response as electrodes for supercapacitor in 5mol/L KOH electrolyte. Furthermore, after 600 galvanostatic charge/ discharge cycles, the supercapacitor still performs a very high stability and efficiency of capacitance.

关键词： reduced graphene oxide (RGO) poly(vinylidene fluoride) (PVDF) nano.,composite supercapacitor

Microstructure and mechanical properties of as-cast(CuNi)100-xCox medium-entropy alloys

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China Foundry 2022年第6期19卷 511-518页

作者： zhi-yong Yang Wei-ping Chen Liang-yan hao Chen-liang Chu Da-hai Zeng Wei Xiong zhi-qiang Fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Physical Metallurgy and Materials Design Laboratory Department of Mechanical Engineering and Materials ScienceUniversity of PittsburghPittsburghPA15261USA National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China

Microstructure and mechanical properties of non-equiatomic(CuNi)_(100-x)Co_(x)(x=15,20,25 and 30,at.%)medium-entropy alloys(MEAs)prepared by vacuum arc-melting were *** show that all the as-cast MEAs exhibit dual face-centered cubic(fcc)solid-solution phases with identical lattice constant,showing typical dendrite structure consisting of(Ni,Co)-rich phase in dendrites and Cu-rich phase in *** positive enthalpy of mixing among Cu and Ni-Co elements is responsible for the segregation of *** the increase of Co content,the volume fraction of(Ni,Co)-rich phase increases while the Cu-rich phase decreases,resulting in an increment of yield strength and a decrement of elongation for the(CuNi)_(100-x)Co_(x) ***-indentation test results show a great difference of microhardness between the two fcc phases of the *** measured microhardness value of the(Ni,Co)-rich phase is almost twofold as compared to that of the Cu-rich phase in all the(CuNi)_(100-x)Co_(x) *** the deformation of the MEAs,the Cu-rich phase bears the main plastic strain,whereas the(Ni,Co)-rich phase provides more pronounced strengthening.

关键词： medium-entropy alloys microstructure mechanical properties nano-indentation

Synthesis, Structure and DFT Investigation into a Copper(II) Compound Consisting of 4,7-diphenyl-1,10-phentheanthroline

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1375-1380页

作者： LI hao-Hong CHEN zhi-Rong REN yong-Gang LI Jun-Qian HUANG Chang-Cang Zhao Bin College of Chemistry and Chemical Engineering Fuzhou University Fuzhou Fujian 350002 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterThe Chinese Academy of SciencesFuzhou Fujian 35002 China

The copper（Ⅱ） DPP adduct Cu（DPP）（DMF）2（H2O）-（ClO4）2 1 （DPP = 4,7-diphenyl-1, 10-phentheanthroline, DMF = N,N＇-dimethyl formamide） has been prepared by a direct synthetic method and structurally characterized. It presents a mononuclear structure and crystallizes in triclinic, space group P1 with a = 9.8717（2）, b = 12.579, c = 14.7574（2） A, α = 67.976（6）,β = 82.031（9）, γ = 80.343（9）°, V = 1668.96（9）A, Z = 1, Dc= 1.495 g/cm^3,/t（MoKα） = 0.877 mm^-1, F（000） = 774, C60H64Cl4Cu2N8O221 Mr = 1502.09, the final R1= 0.0643 and wR2 = 0.1799 for 6153 observed reflections with 1 〉 2σ（1）. Structure analysis shows that copper atom presents an unusual fivecoordination of square pyramid geometry. The whole structure is stabilized by π-π stacking interactions and static attractive forces from [ClO4]-anions. Based on crystal data, quantum chemistry calculation on DFF/B3LPY level was used to reveal the electronic structure of 1.

关键词： Cu(Ⅱ) complexes 4,7-diphenyl-1,10-phentheanthroline DFT calculation

Exact mobility edges and topological phase transition in two-dimensional non-Hermitian quasicrystals

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Science China(Physics,Mechanics & Astronomy) 2022年第2期65卷 82-90页

作者： zhi-hao Xu Xu Xia Shu Chen Institute of Theoretical Physics and State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Chern Institute of Mathematics and LPMC Nankai UniversityTianjin 300071China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Yangtze River Delta Physics Research Center Liyang 213300China

The emergence of the mobility edge(ME)has been recognized as an important characteristic of Anderson *** difficulty in understanding the physics of the MEs in three-dimensional(3 D)systems from a microscopic image encourages the development of models in lower-dimensional systems that have exact *** most of the previous studies are concerned with one-dimensional(1 D)quasiperiodic systems,the analytic results that allow for an accurate understanding of two-dimensional(2 D)cases are *** this work,we disclose an exactly solvable 2 D quasicrystal model with parity-time(PT)symmetry displaying exact *** the thermodynamic limit,we unveil that the extended-localized transition point,observed at the PT symmetry breaking point,is topologically characterized by a hidden winding number defined in the dual *** coupling waveguide platform can be used to realize the 2 D non-Hermitian quasicrystal model,and the excitation dynamics can be used to detect the localization features.

关键词： quasicrystals mobility edges non-Hermitian systems localization properties

Analysis of Norditerpenoid Alkaloids Extracted from Aconitum sinomantanum Nakai by Electrospray Ionization Tandem Mass Spectrometry

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Chemical Research in Chinese Universities 2006年第3期22卷 343-346页

作者： XU Qing-xuan YUE hao LIU zhi-qiang WANG yong YAN Cun-yu LIU Shu-ying Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

Electrospray ionization mass spectrometry（ESI-MS） was applied simultaneously in determining norditerpenoid alkaloids from the roots of Aconitum sinomantanum Nakai （RAS） based on molecular mass information. The tandem mass spectra（ ESI-MS^n） provided the alkaloidal structural information, through which the existence of these alkaloids was further confirmed. Accordingly, six known norditerpenoid alkaloids were simultaneously determined on the basis of their ESI-MS^n spectra. Furthermore, based on the diagnostic fragmentation pathways of alkaloidal MS^n, a rapid method for direct detection and characterization of alkaloids from an ethanolic extract of RAS was described.

关键词： Electrospray ionization tandem mass spectrometry( ESI-MS^n) Norditerpenoid alkaloid Aconitum sinomantanum Nakai