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MASS　CONSERVATION　BEHAVIOR　OF　WAVE　EQUATION　MODEL　FOR　SOLVING　SHALLOW　WATER　EQUATION

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Journal of Hydrodynamics 1995年第4期7卷 1-12页

作者： Wu Jian-kang(huazhong University of science and technology,wuhan 430074,P.R.china) huazhong Univ of science and Technology Wuhan China

Wave equation model(WEM)first developed by Lynch and Gray [2]is one of accurate and effective numerical methods to resolve shallow water *** paper shows the numerical consistency of the second- order wave equation and the first- order continuity equation, analyzes the error between them. This paper also shows that the numerical friction factor τo appearing in wave equation is of key importance to the numerical solutions and mass conservation of wave equation *** calculations of M2 tidal waves in rectangular harbor and a quarter annular harbor are made to demonstrate that it is possible to find a proper numerical friction factor τowith which accurate solutions and satisfactory mass conservation can be achieved by wave equation model.

关键词： numerical calculation tidal waves harbor

Forecasting Loss of Ecosystem Service Value Using a BP Network: A Case Study of the Impact of the South-to-north Water Transfer Project on the Ecological Environmental in Xiangfan, Hubei Province, china

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Biomedical and Environmental sciences 2003年第4期16卷 379-391页

作者： YUN-FENG CHEN, JING-XUAN ZHOU, JIE XIAO, AND YAN-PING LIEnvironmental science and Engineering college, huazhong University of science and technology, wuhan 430074, Hubei, china Environmental science and Engineering college Huazhong University of Science and Technology Wuhan 430074 Hubei Chin

Objective To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific countermeasures. Methods A three-layer BP network was built to simulate topology and process of the eco-economy system of Xiangfan. Historical data of ecological environmental factors and socio-economic factors as inputs, and corresponding historical data of ecosystem service value (ESV) and GDP as target outputs, were presented to train and test the network. When predicted input data after 2001 were presented to trained network as generalization sets, ESVs and GDPs of 2002, 2003, 2004... till 2050 were simulated as output in succession. Results Up to 2050, the area would have suffered an accumulative total ESV loss of RMB 104.9 billion, which accounted for 37.36% of the present ESV. The coinstantaneous GDP would change asynchronously with ESV, it would go through an up-to-down process and finally lose RMB89.3 billion, which accounted for 18.71% of 2001. Conclusions The simulation indicates that ESV loss means damage to the capability of socio-economic sustainable development, and suggests that artificial neural networks (ANNs) provide a feasible and effective method and have an important potential in ESV modeling.

关键词： Artificial neural network BP Ecosystem service value South-to-north Water Transfer Project

INHERITANCE OF PRECIPITATED V_4C_3 IN MARTENSITIC TRANSFORMATION

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 82-88页

作者： XIE Changsheng SUN Peizhen ZHAO Jiansheng SUN Desheng huazhong University of science and technology,wuhan,china huazhong Univ of science and Technology Wuhan China

The inheritance phenomenon of precipitated V_4C_3 in martensitic transformation has been in- vestigated by means of electron diffraction and matrix analysis.A crystallographic orientation relation among austenite,martensite and V_4C_3 carbide was found to be. (010)_A∥( 10)_M∥(010)_(v_4c_3), [10 ]∥[11 ]_M [10 ]_(v_4c_3) The V_4C_3 first precipitated in austenite,and then was inherited to *** cer- tain orientation relation was kept between V_4C_3 and martensite,the interfacial structural ana- lysis pointed out that the biphase interfacial energy is higher than that determined by Baker-Nutting relation,thus it is *** the V_4C_3 precipitated along the crystalline defects in austenite,they could be inherited to martensite.

关键词： V_4C_3 transformation inheritance orientation

Crystallization and Electrical Properties of (Ba_(0.4)Pb_(0.3))Sr_(0.3)TiO_3 Thin Film by Pulsed Laser Deposition

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Journal of wuhan University of technology(Materials science) 2007年第4期22卷 634-637页

作者：杨卫明 Department of Electronic science and technology Huazhong University of Science and Technology

（Ba0.4Pb0.3）Sr0.3TiO3 thin films were fabricated via pulsed laser deposition （PLD） technique on Pt/TiO2/SiO2/Si substrate. The crystallization of the films was characterized by XRD and FSEM, and the experimental results suggested deposition parameters, especially the deposition temperature was the key factor in forming the perovskite structure. The dielectric properties of the film deposited with optimized parameters were studied by an Agilent 4294A impedance analyzer at 1 MHz. The dielectric constant was 772, and the loss tangent was 0.006. In addition, the well-shaped hysteresis loop also showed that the film had a well performance in ferroelectric. The saturated polarization P, remnant polarization Pr and coercive field E were about 4.6 μC/cm2, 2.5 μC/cm2 and 23 kV/cm （the coercive voltage is 0.7 V）, respectively. It is suggested the film should be a promising candidate for microwave applications and nonvolatile ferroelectric random access memories （NvFeRAMs）.

关键词： (Ba0.4Pb0.3)Sr0.3TiO3 thin film PLD dielectric properties ferroelectric properties

Terahertz radiation sources based on free electron lasers and their applications

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science china(Information sciences) 2012年第1期55卷 1-15页

作者： TAN Ping1,HUANG Jiang2,LIU KaiFeng2,XIONG YongQian2&FAN MingWu1,2 1Department of Electronic and Information Engineering,huazhong University of science and technology,wuhan 430074,china 2college of Electrical and Electronic Engineering,State Key Laboratory of Advanced Electromagnetic Engineering and technology,huazhong University of science and technology,wuhan 430074,china 1. Department of Electronic and Information Engineering Huazhong University of Science and Technology Wuhan 430074 China2. College of Electrical and Electronic Engineering State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan 430074 China

The tunability,high power and flexible picoseconds-pulse time structure of terahertz(THz)radiation make the THz free-electron laser(FEL)a very attractive THz source of coherent *** paper focuses on the development and perspectives of THz radiation sources based on the *** principles of the low gain THz FEL oscillator,the SASE THz FEL amplifier and the supperradiant THz FEL are reviewed briefly,and the key technologies of THz FEL,such as injector,accelerator,undulator and optical cavity,are discussed,*** current status of and future prospects for THz radiation sources based on the FEL are emphasized in this *** research and development have shown bright future in free-electron laser(FEL)THz radiation *** potential applications can be carried out in the field of imaging,material research,biology medicine,communication,diagnostics and many others.

关键词： terahertz source terahertz applications free electron laser

Structure and Magnetic Properties of Ni-doped ZnO Powder

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Journal of wuhan University of technology(Materials science) 2010年第5期25卷 770-773页

作者：高放赵俊 Department of Electronic science and technology Huazhong University of Science and Technology

Ni-doped ZnO nanopowder （Zn0.98Ni0.2O） was synthesized by improved coprecipitation method. The average particle size of the powder was estimated to be 50 nm. The powder was then processed by thermal treatment. Samples were annealed at 1 073, 1 273, and 1 473 K, respectively. The solubility of NiO in ZnO and the lattice parameters of ZnO both increased with the temperature. The magnetic property of the doped samples was examined, and hysteresis loops were got. The results showed all the samples were ferromagnetic, while powder processed at 1 273 K for 4 h got a highest saturation magnetization （Ms） of 0.0457 emu/g. Also, magnetic properties were related to the grain size of the powder.

关键词： ferromagnetism diluted magnetic semiconductor Ni-doped ZnO coprecipitation solid state reaction

Nano-flower spherical SnS2 combined with a special lithium storage mechanism as a multifunctional separator for lithium-sulfur batteries contributes to ultra-high initial discharge specific capacity

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science china(Technological sciences) 2024年第2期67卷 509-519页

作者： LIU huazhong XIONG YaPing HUANG MouZhi CHEN ZongMin YANG Xiao ZHANG Ze YANG ZhenYu CAI JianXin School of Chemistry&Chemical Engineering Nanchang UniversityNanchang 330031China

The critical factors that limit the electrochemical performance of lithium-sulfur(Li-S)batteries are mainly the“shuttle effect”of polysulfides and the slow redox reaction between lithium polysulfides(LiPSs).Herein,a nano-sphere-type material selfassembled from tin disulfide nanosheets is designed and applied to the Li-S cell separator in this *** SnS_(2)@PP modified separator not only acts as a dual restriction for LiPSs by chemisorption and physical *** the same time,it improves the catalytic activity of the redox reaction between *** SnS_(2)has extremely high electrochemical ***,a portion of the lithium ions can be inserted into SnS_(2)to form Li_(x)SnS_(2)and contribute to the capacity during the first discharge of the *** addition,Li_(x)SnS_(2)possesses a high degree of stability,and it does not undergo further de-alloying reactions even at the high potential of the Li-S *** benefit is that the steady-state Li_(x)SnS_(2)acts as a lithium-containing *** can form special Li^(+)channels on the surface of the separator,thus greatly improving the efficiency of Li+*** results showed that the SnS_(2)@PP-based cell exhibited extremely high initial discharge specific capacity(1477 m Ah g^(-1)at 0.1 C)and excellent rate performance(631 m Ah g^(-1)at 5 C).Even after 1000 cycles at 2 C,the cell exhibited a low decay rate of 0.06%per cycle on *** addition,the superior electrochemical performance was obtained even with a high sulfur loading of 5.1 mg cm^(-2)and low electrolyte of E/S=8μL mg^(-1).

关键词： Li-S batteries modified separators polysulfides catalytic conversion high electrochemical activity

Synthesis of cystine C_(60) derivative and its protective effects on hydrogen peroxide-induced apoptosis in PC12 cells

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Chinese Chemical Letters 2007年第2期18卷 145-148页

作者： Zhen Hu, Hai Ping Xing, Zhou Zhu, Wei Wang, Wen Chao Guan Department of Chemistry, huazhong University of science and technology, wuhan 430074, china Department of Neurology, Tongji Hospital, Tongji Medical college, wuhan 430030, china [a]Department of Chemistry Huazhong University of Science and Technology Wuhan 430074 China [b]Department of Neurology Tongji Hospital Tongji Medical College Wuhan 430030 China

Oxidative stress has been considered as a major cause of cellular injuries in a variety of clinical abnormalities, especially prominent in neural diseases. One of the usable ways to prevent the reactive oxygen species (ROS)-mediated cellular injury is dietary or pharmaceutical augmentation of some free radical scavenger. Water-soluble amino-fullerene is a novel compound that behaves as a free radical scavenger with excellent biology consistent. In the present study, we have synthesized and characterized a novel cystine C60 derivative for the first time, and investigated the effects on hydrogen peroxide-induced oxidative stress and apoptotic death in cultured rat pheochromocytoma (PC12) cells. PC12 cells treated with hydrogen peroxide underwent apoptotic death as determined by MTT, PI/Hoechst 33342 staining and flow cytometry analysis. These results suggested that cystine C60 derivative has the potential to prevent oxidative stress-induced cell death and has no evident toxicity.

关键词： Cystine C_(60) derivative Reactive oxygen species H_2O_2 Apoptosis PC 12 cells

Inhibitory Effect of HCPT on Expression of HIF-1α and Downstream Genes in Hypoxic Human Cervical SiHa Cancer Cells

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Journal of huazhong University of science and technology(Medical sciences) 2007年第5期27卷 586-589页

作者：施薇于世英 Cancer Center Tongji Hospital Tongji Medical College Huazhong University of Science and Technology

The hypoxic model to simulate hypoxic microenvironment in solid tumors was established and the effect of hydrocamptothecin （HCPT） on the hypoxia-induced over-expression of HIF-1α and VEGF genes was explored. Human cervical cancer SiHa cells were cultured in vitro under hypoxic conditions （37℃, 5% CO2, 1%O2） and treated with different concentrations of HCPT for 24 h. The mRNA and protein expression levels of HIF-1α, VEGF and Glutl in SiHa cells were detected by semi-quantitative RT-PCR and Western blot respectively. Normoxic control groups were exposed to normoxic conditions for 24 h. Under normoxic conditions, HCPT had no obvious effects on the HIF-1α and VEGF gene expression. Hypoxia induced the up-regulation of HIF-1α protein and downstream VEGF gene, and HCPT showed a dose-dependently inhibitory effect on the hypoxia-induced over-expression of HIF-1α protein and VEGF gene expression in SiHa cells, whereas HCPT had no significant effect on the HIF-1α mRNA expression. No difference in HCPT cytotoxic- ity was observed between hypoxic groups and normoxic control groups. It was suggested that HCPT could inhibite the expression of HIF-1α protein and downstream VEGF gene in hypoxic SiHa cells in a dose-dependent manner, and the inhibitory effect was not related with HCPT cytotoxicity.

关键词： hydrocamptothecin HIF-1α VEGF cervical cancer