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Effects of Bahia Grass Cover and Mulch on Runoff and Sediment Yield of Sloping Red Soil in Southern china

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Pedosphere 2011年第2期21卷 238-243页

作者： LI Xin-Hu ZHANG Zhan-Yu YANG Jie ZHANG Guo-Hua WANG Bin College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 (China) Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil Hohai university Nanjing 210098 (China) Jiangxi Institute of Soil and Water Conservation Nanchan9 330029 (China) china Irrigation and Drainage Development Center Beijing 100054 (China) College of Water Conservancy and Building Engineering Northeast Agricultural University Harbin 150030 (China)

Rainfall,runoff (surface runoff,interflow and groundwater runoff) and soil loss from 5 m × 15 m plots were recorded for 5 years (2001-2005) in an experiment with three treatments (cover,mulch and bare ground) on sloping red soil in southern *** runoff and erosion from the Bahia grass (Paspalum notatum Flugge) cover plot (A) and mulch plot (B) during the 5 years were low,despite the occurrence of potentially erosive *** contrast,the bare plot (C) had both the highest surface runoff coefficient and the highest sediment *** were significant differences in interflow and surface runoff and no significant difference in groundwater runoff among *** runoff coefficients and duration of interflow and groundwater runoff were in the order plot B > plot A > plot *** of Bahia grass cover were excellent,indicating that the use of Bahia grass cover can be a simple and feasible practice for soil and water conservation on sloping red soil in the region.

关键词： groundwater runoff interflow lysimeter soil properties surface runoff

Negative refraction in two-dimensional photonic crystals

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Progress in Natural Science:Materials International 2006年第10期16卷 1027-1032页

作者： REN Xiaobin, REN Kun, FENG Zhifang, FENG Shuai and REN Cheng ( School of Physics Science and Information Technology, Liaocheng university, Liaocheng 252059, china beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, beijing 100080, china) [a]School of physics Science and Information Techonolgy Liaocheng University Liaocheng China [b]beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China

Recent progress made in research on negative refraction in two-dimensional photonic crystals is reviewed. Special attentions are paid to the research results of our group. We explore the underlying mechanism governing the occurrence of negative refraction in periodic and quasiperiodic photonic crystals. These results may be useful references for the application of photonic crystals. The perspectives of future research on negative refraction are briefly predicted.

关键词： negative refraction photonic crystals superlens subwavelength imaging equifreqnency surface.

SYNTHESIS OF TiN BY MICROWAVE CARBOTHERMAL REDUCTION OF TiO_2

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Acta Metallurgica Sinica(English Letters) 1998年第4期11卷 291-295页

作者： B.H Liu Y Zhang S.X. Ouyang and H.C. Gu (Research Institute of Technical Chemical Physics, East china university of Science and Technology,Shanghai 200237, china)(department of Materials Physics, university of Science and Technology beijing, beijing 10 East china Univ of Science and Technology Shanghai China

Titanium nitride powder was synthesized by microwave carbothermal reduction of titanium oxide. The mechanism and thermal dynamics of the reaction process were studied. The results show that the microwave carbothermal reduction technology has unique advantages over the conventional reduction methods. It can not only lower the reaction temperature, shorten the synthesis cycle, but also refine the product particles,as well as improving the reactivity of the powder.

关键词： TiN microwave carbothermal reduction

Microstructure and Mechanical Properties of Heat-treated GeSb_2Te_4 Thin Films

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Journal of Wuhan university of Technology(Materials Science) 2007年第2期22卷 196-200页

作者：丁建宁解国新 Micro/Nano Science & Technology Center Jiangsu University State Key Laboratory of Tribology Tsinghua University

The effect of annealing on microstructure, adhesive and frictional properties of GeSb2Te4 films were experimentally studied. The GeSb2Te4 films were prepared by radio frequency （RF） magnetron sputtering, and annealed at 200℃ and 340℃ under vacuum circumstance, respectively. The adhesion and friction experiments were mainly conducted with a lateral force microscope （LFM） for the GeSb2Te4 thin films before and after annealing. Their morphology and phase structure were analyzed by using atomic force microscopy （AFM） and X-ray Diffraction （XRD） techniques, and the nanoindention was employed to evaluate their hardness values. Moreover, an electric force microscope （EFM） was used to measure the surface potential. It is found that the deposited GeSb2Te4 thin film undergoes an amorphous-to-fcc and fcc-to-hex structure transition; the adhesion has a weaker dependence on the surface roughness, but a certain correlation with the surface potential of GeSb2Te4 thin films. And the friction behavior of GeSb2Te4 thin films follows their adhesion behavior under a lower applied load. However, such a relation is replaced by the mechanical behavior when the load is relatively higher. Moreover, the GeSb2Te4 thin film annealed at 340℃ presents a lubricative property.

关键词： GeSb2Te4 films annealing microstructure mechanical properties friction

MATHEMATICAL MODELLING OF FLOW PHENOMENA IN METAL BATH COVERED WITH MOLTEN SLAG

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Acta Metallurgica Sinica(English Letters) 1990年第12期3卷 370-376页

作者： QU Ying YANG Jian XU Baomei university of Science and Technology beijing,beijing,china

By use of the two-component LDA and high speed camera,the water model of the flow field in metal bath under molten slag layer has been *** the basis of experimental results,the flow boundary conditions of liquid metal at the slag-metal interface of a gas injecting bath were *** flow field and the turbulent parameters of the metal bath covered with slag were solved by the vorticity-stream function *** results reveal that the flow velocity, turbulent energy and circulating rate of the melt under slag are lower than that of without *** one “dead zone” of the lowest turbulent energy is formed in the top layer under cover of slag near the ladle linning.

关键词： flow field metal bath injection metallurgy mathematical modelling

Emergency access mechanism in IEEE 802.15.4 for wireless body area sensor networks

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The Journal of china Universities of Posts and Telecommunications 2009年第6期16卷 24-31页

作者： GUO Yan-yan,KANG Gui-xia,CAO Yu,ZHANG Ping Key Laboratory of Universal Wireless Communications,Ministry of Education,beijing university of Posts and Telecommunications,beijing 100876,china [a] Key Laboratory of Universal Wireless Communications Ministry of Education beijing university of Posts and Telecommunications beijing 100876 china

IEEE 802.15.4 protocol has attracted much attention in research and industrial communities as candidate technology for wireless body area sensor networks（WBASNs）.IEEE 802.15.4 supports the exclusive use of a wireless channel through guaranteed time slot（GTS）.However,on one hand,bandwidth underutilization rate may be lower because of the variance between the guaranteed bandwidth and the arrival *** the other hand,the waiting time for transmitting emergency notification is getting longer when the GTSs assigned to the nodes increase in *** solve these problems,in this article,a new scheme is proposed to reduce transmission delay for the alarm notification in emergent *** results are presented to validate the efficiency of the proposed scheme by comparing it with the medium access control（MAC） protocol of IEEE 802.15.4.

关键词： WBASN GTS IEEE 802.15.4 emergency mechanism

Optimization of Processing Parameters for Laser Powder Deposition using Finite Element Method

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Journal of Wuhan university of Technology(Materials Science) 2010年第5期25卷 832-837页

作者：付垚 State Key Laboratory of Non-ferrous Metals and Processes General Research Institute for Non-ferrous Metals

In order to investigate the effects of powder materials and processing parameters on thermal and stress field during laser powder deposition （LPD）, a finite element model was developed with the help of ANSYS software. The finite element model was verified by the comparison between the experimental results and computed results. Then LPD processes with different powder materials and processing parameters were simulated by using the FE model. The results show that less difference of thermal conductivity and thermal expansion coefficient between powder material and substrate material produces lower residual stress; higher laser power, laser scanning speed and smaller laser beam diameter can lead higher peak temperature and higher residual stress. The research opens up a way to rational selection of the powder materials and processing parameters for ensured quality.

关键词： laser powder deposition thermal field stress field powder material processing parameters

Overexpression of heat-shock protein 20 in rat heart myogenic cells confers protection against simulated ischemia/reperfusion injury

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Acta Pharmacologica Sinica 2005年第9期26卷 1076-1080页

作者： Yan-hui ZHU Xian WANG~2 department of Physiology and Pathophysiology,Basic Medical College,Key Laboratory of Molecular Cardiovascular Biology,Ministry of Education,Peking university,beijing 100083,china departmentofPhysiologyandPathophysiology BasicMedicalCollegeKeyLaboratoryofMolecularCardiovascularBiologyMin

Aim:To explore whether overexpression of the small heat shock protein HSP20 inrat cardiomyocytes protects against simulated ischemia/reperfusion(SI/R)***:Recombinant adenovirus expressing HSP20 was used to infect rat H9c2cardiomyocytes at high efficiency,as assessed by green fluorescent protein.H9c2cells were subjected to SI/R stress;survival was estimated through assessment oflactate dehydrogenase and cell apoptosis through caspase-3 ***:Overexpression of HSP20 decreased lactate dehydrogenase release by 21.5% andcaspase-3 activity by 58.8%.Pretreatment with the protein kinase C inhibitor Ro-31-8220(0.1 μmol/L)for 30 min before SI/R canceled the protective effect of *** selective mitochondrial K+awP channel inhibitor 5-hydroxydecanoate(100 μmol/L)had a similar ***,the non-selective K~+ATPchannel inhibitorglibenclamide(100 μmol/L)had no significant ***:These dataindicate that the protective effect of HSP20 in vitro is primarily due to reducednecrotic and apoptotic death of cardiomyocytes,possibly via the protein kinaseC/mitochondrial K~+ATP pathway.

关键词： reperfusion injury adenovirus apoptosis necrosis heat-shock proteins

Multi-Layered Low-Angle Ductile Detachment System in Dabie-Sulu UHPM and HPM Belts, china

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Journal of Earth Science 1999年第3期18卷 187-193页

作者： Suo Shutian Zhong Zengqiu(Faculty of Earth Sciences, china university of geosciences, Wuhan 430074) Faculty of Earth Sciences China University of Geosciences Wuhan 430074

The present-day observed crustal-scale tectonic style of ultrahigh-pressure metamorphic (UH-PM) and high-pressure metamorphic (HPM ) belts in the Dabie-Sulu region was dominantly formedby extensional processes, postdating the Triassic collision between the Sino-Korean and Yangtze cratons. The extensional structures overprinting the previous structures related to contraction that produced the thickened continental crust of the UHPM and HPM belts, in particular display the typical features of a Cordilleran-type metamorphic core complex, in which at least four regionalscale, low-angle ductile shear zones that constitute a detachment system, are recognized in the Dabie region. In the Sulu region, the extensionaI structures show in the form of small-scale domes or a regional-scale SE-dipping pseudo-monocline. The geometry and the kinematics of tbe detachment zones are briefly described and their significance for the exhumation of UHPM and HPM rocks is discussed. It is iniliated that the subhorizontal crustal-scale extensional flow in the middle-lower crust, under amphibolite- to greenschist-facies conditions, was an important tectonothermal process at 200- 170 Ma and the exhumation or the UHPM and HPM rocks was achieved at least in part along multi-layered detachment zones. The regional detachment system has been the main factor enabling UHPM and HPM rocks to be brought from middle-lower crustal levels to middle-upper crustal levels.

关键词： detachment system UHPM and HPM rocks exhumation ductile shear zone,Dabie massif Dabie-Sulu region