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Effects of moss-dominated biocrusts on soil detachment by overland flow in the Three Gorges Reservoir Area of China

Journal of Mountain Science 2020年第10期17卷 2418-2431页

作者： ZHANG Guan-hua DING Wen-feng PU jian LI jian-ming QIAN feng SUN Bao-yang Soil and Water Conservation Department Changjiang River Scientific Research InstituteWuhan430010China Research Center on Mountain Torrent&Geologic Disaster Prevention of Ministry of Water Resources Wuhan430010China

Biological soil crusts(biocrusts)are important landscape components that exist in various climates and *** roles of biocrusts in numerous soil processes have been predominantly recognized in many dryland regions ***,little is known about their effects on soil detachment process by overland flow,especially in humid *** study quantified the effects of moss-dominated biocrusts on soil detachment capacity(Dc)and soil erosion resistance to flowing water in the Three Gorges Reservoir Area which holds a subtropical humid *** factors driving soil detachment variation and their influencing mechanism were analyzed and *** designed five levels of coverage treatments(1%–20%,20%–40%,40%–60%,60%–80%,and 80%–100%)and a nearby bare land as control in a mossdominated *** soil samples were taken and subjected to water flow scouring in a hydraulic flume under six shear stresses ranging from 4.89 to 17.99 *** results indicated that mean Dc of mosscovered soil varied from 0.008 to 0.081 kg m^-2 s^-1,which was 1.9 to 21.0 times lower than that of bare soil(0.160 kg m^-2 s^-1).Rill erodibility(Kr)of mosscovered soil ranged from 0.0095 to 0.0009 s m^-1,which was 2 to 20 times lower than that of bare soil(0.0187 s m^-1).Both relative soil detachment rate and Kr showed an exponential decay with increasing moss coverage,whereas the critical shear stress(τc)for different moss coverage levels did not differ *** coverage,soil cohesion,and sand content were key factors affecting Dc,while moss coverage and soil bulk density were key factors affecting Kr.A power function of flow shear stress,soil cohesion,and moss coverage fitted well to estimate Dc(NSE=0.947).Our findings implied that biocrusts prevented soil detachment directly by their physical cover and indirectly by soil properties *** could be rehabilitated as a promising soil conservation measure during ecological recovery to enhance so

关键词： Soil detachment Soil erosion resistance Rill erodibility Biological soil crusts yangtze River

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Adsorption of Ag on M-doped graphene:First principle calculations

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 487-494页

作者： Min Hu Zhou Fan jian-yi Liu Kun Zhang yang Wang Chun-feng yang School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering Southwest Petroleum UniversityChengdu 610500China Journal Center Southwest Petroleum UniversityChengdu 610500China

Graphene is an ideal reinforcing phase for a high-performance composite filler,which is of great theoretical and practical significance for improving the wettability and reliability of the ***,the poor adsorption characteristics between graphene and the silver base filler significantly affect the application of graphene filler in the brazing *** is a great challenge to improve the adsorption characteristics between a graphene and silver base *** solve this issue,the adsorption characteristic between graphene and silver was studied with first principle *** effects of Ga,Mo,and W on the adsorption properties of graphene were *** are three possible adsorbed sites,the hollow site(H),the bridge site(B),and the top site(T).Based on this research,the top site is the most preferentially adsorbed site for Ag atoms,and there is a strong interaction between graphene and Ag *** element doping enhances local hybridization between C or metal atoms and ***,compared with other doped structures(Ga and Mo),W atom doping is the most stable adsorption structure and can also improve effective adsorption characteristic performance between graphene and Ag.

关键词： graphene filler first principle calculations adsorption characteristic

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Analysis of Modified Williamson-Hall Plots on GaN Layers

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Chinese Physics Letters 2011年第1期28卷 145-148页

作者： LIU jian-Qi QIU Yong-Xin WANG jian-feng XU Ke yang Hui Platform for Characterization & Test Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215125 Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 Graduated University of Chinese Academy of Sciences Beijing 100049

Williamson Hall （W-H） analysis is often used to separate the lateral coherence length （LCL） broadening and dislocation broadening＂ on the ω-sean with a Lorentzian distribution. However, besides the LCL broadening and dislocation broadening, curvature also can broaden the w-scan peak. Usually, the w-scan can be described by a Pseudo-Voigt （P-V） function more precisely than a Lorentzian function. Based on the P-V fit peak profile, we modify the W-H plots. Both LCL broadening and curvature broadening can be eliminated from （OOl） ω-scans plots simultaneously, and a reliable tilt can be obtained. This method is a good complementary for the existing method, but is more convenient. Although we focuse on GaN layers, the results are applicable to a wide range of other materials having mosaic structures.

关键词： Surfaces interfaces and thin films Condensed matter: structural mechanical & thermal

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Effects of Haobie yangyin Ruanjian Decoction on hepatic fibrosis induced by carbon tetrachloride in rats

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World Journal of Gastroenterology 2010年第12期16卷 1458-1464页

作者： yang, feng-Rui Fang, Bu-Wu Lou, jian-Shi Tianjin Med Univ Dept Pharmacol Tianjin 300070 Peoples R China

AIM:To explore the anti-fibrotic effect of Haobie yangyin Ruanjian Decoction(HYRD)on CCl4-induced hepatic fibrosis in rats and its modulation on the transforming growth factor(TGF)β-Smad signaling ***:Fifty-six healthy Wistar rats were randomly divided into five groups:normal control group(n=6),CCl4-induced hepatic fibrosis group(n=14) and three treatment groups(the treated rats received HYRD via oral administration at daily dosages of 8.2,2.5 and 0.82 g/kg,respectively)of HYRD(n=12,respectively).Experimental hepatic fibrosis was induced by subcutaneous injection of carbon tetrachloride solution(CCl4 dissolved in peanut oil,4:6,V/V)with 0.5 mL/100 g body weight for the first time,and then 0.3 mL/100 g body weight twice a week for 8 *** the former 2 wk,rats were raised by feedstuffⅠ(80% corn meal,20%lard,0.5%cholesterol).After 2 wk,they were raised by feedstuffⅡ(corn meal and 0.5% cholesterol).Except for the control group,30%alcohol solution was given orally to each rat every other day from the beginning,1 mL for each *** function parameters and hepatic hydroxyproline content were detected by *** levels of hyaluronic acid(HA),typeⅣcollagen(CIV),typeⅢprecollagen(PCⅢ)and laminin(LN)were assayed with *** of collagen was observed with hematoxylin-eosin staining and collagen *** expression of TGFβ1 and Smad3 were detected with real-time reverse transcriptase-polymerase chain reaction and Western blotting,***:The serum levels of alanine transaminase and aspartate transaminase were increased in the model group compared with the control group(P<0.01),and they were decreased in the three treatment groups compared with the model *** serum levels of total protein and albumin were decreased in the model group and increased in the three treatment *** hepatic hydroxyproline content and serum levels of PCⅢ,HA,LN and CIV were markedly increased in the model group compared with the con

关键词： Haobie yangyin Ruanjian Decoction Hepatic fibrosis Transforming growth factorβ-Smad signaling Rat model Carbon tetrachloride

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Comparison of AC breakdown characteristics on insulation paper (pressboard) immersed by three-element mixed insulation oil and mineral oil

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High Voltage 2020年第3期5卷 298-305页

作者： Dawei feng jian Hao Lijun yang Ruijin Liao Xin Chen jian Li State Key Laboratory of Power Transmission Equipment and System Security and New Technology School of Electrical EngineeringChongqing UniversityChongqing 400044People's Republic of China

Insulation oil is an important dielectric in power devices,and many studies on mixed insulation oil have been conducted in recent years to improve the performance of insulation *** replace mineral oil directly,the authors previously developed a novel three-element mixed insulation oil successfully;the main parameters of which satisfy the IEC 60296-2012 standard for mineral *** the present study,the AC breakdown properties of insulation paper(pressboard)immersed by the new mixed oil and naphthenic mineral oil were *** both insulation oils,the increase in temperature cannot significantly reduce the breakdown strength of oil-immersed insulation paper(pressboard)at a low moisture content,and the increment of moisture content cannot reduce the breakdown voltage at a low temperature(25℃).The breakdown voltage decreases only when the two factors increase *** the mixed and mineral oils,the AC breakdown voltage of oilimmersed paper(pressboard)with different thicknesses has significant *** mineral oil has a high breakdown voltage for the thin insulation paper,whereas the mixed oil has a high breakdown voltage when the thickness of the insulation paper(pressboard)exceeds 0.2 *** phenomenon is mainly caused by the breakdown field strength that varies with the increase of dielectric thickness and the different change trends of paper(pressboard)immersed with the mixed and the mineral ***,the stack of thin multilayer insulation paper enables the mixed oil-immersed paper to have a higher breakdown strength than the mineral oil-immersed *** the AC breakdown voltage of oil-immersed pressboard with an oil-gap structure,the mixed oil is comprehensively superior to the mineral oil due to its larger relative permittivity.

关键词： insulation immersed breakdown

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Pilot power based rate control in CDMA 2000 1x EV-DO Rev-A

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 118-122页

作者： LIU Xiao-feng GU jian yang Hong-wen Wireless communication Center Beijing University of Posts andTelecommunications Beijing 100876 China

This article proposes a new algorithm to improve the rate control efficiency of enhanced reverse link medium access control （RLMAC） in the code division multiple access （CDMA） 1x EV-DO release A（Rev. A） system. The new algorithm brings reverse access terminal （AT） pilot power to the RLMAC rate control procedure and makes it easier for a low pilot power user to increase its data rate when the system is slightly loaded and harder to decrease its date rate when the system is heavily loaded. Numerical results of system level simulations show that the new algorithm can bring higher system throughput, lower AT transmission power, and lower system load.

关键词： RLMAC CDMA 1x EV-DO pilot power rate control

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石墨烯改性方法对树脂基炭刷载流磨损性能影响研究

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炭素 2016年第4期 19-27,42页

作者：宋腾辉涂川俊邓联谱熊建林冯鹏洋张剑宇湖南大学材料科学与工程学院长沙410082 长沙奥博碳制品有限公司长沙410152

本文采用直接混合和液态混合两种不同工艺制备了石墨烯改性树脂基炭刷材料,对炭刷材料进行物理性能和载流磨损性能测试,采用SEM、EDS等方法对炭刷材料磨损面形貌及成分进行表征。结果表明:石墨烯的加入能够有效的提高炭刷材料的抗磨性能... 详细信息

本文采用直接混合和液态混合两种不同工艺制备了石墨烯改性树脂基炭刷材料,对炭刷材料进行物理性能和载流磨损性能测试,采用SEM、EDS等方法对炭刷材料磨损面形貌及成分进行表征。结果表明:石墨烯的加入能够有效的提高炭刷材料的抗磨性能,采用直接混合2wt%石墨烯和液态混合1wt%石墨烯制备炭刷材料载流磨损率分别降低28/和38%。直接混合法加入石墨烯提高了炭刷强度,减少了磨屑的产生,石墨烯能够调节炭刷磨损面,提高炭刷材料的润滑性能,降低磨抿液态混合法加入石墨烯增强了炭刷材料的韧性,有助于炭刷表面复合润滑膜的形成,避免了磨屑产生,有效降低磨损。

关键词：石墨烯树脂炭刷载流磨损减磨抗磨

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军队院校任职教育实验教学改革的思考

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教育教学论坛 2017年第9期 114-115页

作者：黄靖徐建霖杨锋甄洪斌罗宁昭海军工程大学电气工程学院湖北武汉430033

加强任职教育实验教学,对深入推进任职教育改革,有效提高岗位任职实践能力培养的效果水平和,具有十分重要的意义。本文以任职教育与学历教育实验教学的区别出发,深入分析了任职教育实验教学的特点,并在此基础上,就如何搞好任职教育实验... 详细信息

加强任职教育实验教学,对深入推进任职教育改革,有效提高岗位任职实践能力培养的效果水平和,具有十分重要的意义。本文以任职教育与学历教育实验教学的区别出发,深入分析了任职教育实验教学的特点,并在此基础上,就如何搞好任职教育实验教学改革从任职教育实验课程体系改革、综合考评方法设计和教员队伍建设等方面提出针对性建议。

关键词：任职教育实验教学课程体系

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Understanding Structural Evolution in the Synthesis of Advanced Energy Materials

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Chinese Journal of Structural Chemistry 2020年第1期39卷 26-30,1页

作者： ZHANG Ming-jian CHEN Yu-Sheng PAN feng REN yang School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen 518055China Center for Advanced Radiation Source(ChemMatCARS) the University of ChicagoArgonneIllinois 60439United States X-ray Science Division Argonne National LaboratoryArgonneIL 60439United States

Developing a variety of in situ characterization techniques to unravel the structural/chemical evolution during the synthesis of various advanced energy materials for studying the relationship among those experimental conditions and the structure is the key to implement the controllable synthesis of battery *** perspective summarizes the recent studies into structural evolution during in situ synthesis of various advanced energy materials by synchrotron X-ray diffraction technique and forecasts the more extensive applications in the future.

关键词： structure evolution synthesis advanced energy materials in situ synchrotron X-ray diffraction

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Ligand-accelerated, branch-selective oxidative cyanation of alkenes

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Science Bulletin 2018年第22期63卷 1479-1484页

作者： Jun yang Huan Li jian Qin Fan Song jian Zhang feng-Ling Qing Lingling Chu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Chemistry Chemical Engineering and Biotechnology Center for Advanced Low-Dimension Materials Donghua University Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

A ligand-accelerated, branch-selective oxidative cyanation of alkenes has been developed in the presence of catalytic Cu_*** styrenes and aliphatic alkenes with directing groups are well tolerated in this inexpensive *** mild condition allows for a good tolerance of functional groups, enabling facile access to a diverse array of simple and complex branched vinyl *** wide synthetic utility of this methodology has been further demonstrated via the efficient scaleup in both batch and continuous flow processes.

关键词： Vinyl nitrile Cyanation Branch-selective Alkene Copper catalysis

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