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Integration of supertetrahedral cluster with reduced graphene oxide sheets for enhanced photostability and photoelectrochemical properties

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Science China Chemistry 2013年第4期56卷 423-427页

作者： HOU yang wu Tao WANG Le feng PingYun Department of Chemistry University of California

Supertetrahedral zinc-gallium-tin sulfide cluster modified with reduced graphene oxide protective layer was first synthesized, which exhibited an excellent photoelectrochemical performance and enhanced stability in co... 详细信息

关键词： supertetrahedral cluster OCF-40-ZnGaSnS reduced graphene oxide protective layer photoelectrochemical activity

Relationship Between the Formation of Clusters in Electrorheological Fluids and Their Fractal Dimension

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Chinese Physics Letters 1995年第8期12卷 501-504页

作者： wu feng TANG Xinlu yang Yuegui WANG Xiaohong Department of Modern Mechanics University of Science and Technology of ChinaHefei 230026

In this paper,the scaling properties of aggregation of particles in electrorheological fluids(ERF)are *** is found that the cluster size is related to both the space dimension and its fractal dimension,*** structure of *** analyzing the experimental data and the results of computer simulations we have shown that the fractal dimension of the particle clusters in ERF is one for 2-dimensional space and 5/4 for 3-dimensional space.

关键词： cluster. space. dimension

A novel and efficient strategy involving a CuI catalyzed cascade reaction to synthesize acenaphtho[1,2-b]quinoline derivatives

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Chinese Chemical Letters 2016年第3期27卷 349-352页

作者： Hong-Kun yang Yuan-feng Tong Song wu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical College

A novel and efficient approach for the straightforward synthesis of biologically significant acenaphtho[1,2-b]quinoline derivatives in good yields utilizing CuI as a catalyst with a broad array of substrates has been developed. The strategy features as a CuI-catalyzed cascade reaction involving the formation of two new C–C bonds and one new C–N bond with high atom economy. A proposed mechanism for the reaction is described.

关键词： Cascade reaction CuI Substituted anilines Phenylethynyl-1-naphthaldehydes Acenaphtho[1 2-b]quinolones

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

5083铝合金在淡海水交替自然环境中的腐蚀行为研究

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装备环境工程 2017年第2期14卷 40-45页

作者：陈翔峰杨博均吴波姚敬华任润桃海洋腐蚀与防护国防科技重点实验室福建厦门361101 中船重工七二五研究所厦门分部福建厦门361101

目的研究5083铝合金在淡海水交替自然环境下的耐蚀性能。方法参照GB/T 5776,分别在淡海水交替、海水及淡水自然环境中开展5083铝合金2年的耐浸泡试验。采集每周期试验样品的腐蚀数据,并进行5083铝在三种自然水环境下的耐蚀性能比对。采... 详细信息

目的研究5083铝合金在淡海水交替自然环境下的耐蚀性能。方法参照GB/T 5776,分别在淡海水交替、海水及淡水自然环境中开展5083铝合金2年的耐浸泡试验。采集每周期试验样品的腐蚀数据,并进行5083铝在三种自然水环境下的耐蚀性能比对。采用腐蚀电位、交流阻抗等电化学方法,对其耐蚀性能进行评价。结果 5083铝在淡海水交替自然环境下腐蚀严重,腐蚀速率是海水环境下的5.3倍,是淡水环境下的15.8倍。点蚀密度最大,平均点蚀深度是海水环境下的2.6倍,是淡水环境下的1.7倍。结论 5083铝在淡海水交替自然环境下的耐蚀性差,并从电化学试验结果上得到很好的验证。

关键词： 5083铝合金淡海水交替电化学腐蚀

Study of total variation diminishing (TVD) slope limiters in dam-break flow simulation

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Water Science and Engineering 2018年第1期11卷 68-74页

作者： feng-peng Bai Zhong-hua yang wu-gang Zhou State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

A two-dimensional （2D） dam-break flow numerical model was developed based on the finite-volume total variation diminishing （TVD） and monotone upstream-centered scheme for conservation laws （MUSCL）-Hancock scheme, which has second-order accuracy in both time and space. A Harten-Lax-van Leer-contact （HLLC） approximate Riemann solver was used to evaluate fluxes. The TVD MUSCL-Hancock numerical scheme utilizes slope limiters, such as the minmod, double minmod, superbee, van Albada, and van Leer limiters, to prevent spurious oscillations and maintain monotonicity near discontinuities. A comparative study of the impact of various slope limiters on the accuracy of the numerical flow model was conducted with several dam-break examples including wet and dry bed cases. The numerical results of the superbee and double minmod limiters agree better with the theoretical solution and have higher accuracy than other limiters in one-dimensional （1D） space. The ratio of the downstream water depth to the upstream water depth was used to select the proper slope limiter. For the 2D numerical model, the superbee limiter should not be used, owing to significant numerical dispersion.

关键词： Dam-break flow TVD MUSCL-Hancock scheme Slope limiter Numerical accuracy Spurious oscillation

Effects of physical soil crusts on infiltration and splash erosion in three typical Chinese soils

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International Journal of Sediment Research 2014年第4期29卷 491-500页

作者： Chong-feng BU Shu-fang wu Kai-bao yang Northwest A&F University State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources College of Water Resources and Architectural Engineering Northwest A&F University College of Natural Resources and Environment Northwest A&F University

Physical soil crusts likely have significant effects on infiltration and soil erosion,however,little is known on whether the effects of the crusts change during a rainfall ***,there is a lack of discussions on the differences among the crusting effects of different soil *** objectives of this study are as follows:（i） to study the effects of soil crusts on infiltration,runoff,and splash erosion using three typical soils in China,（ii） to distinguish the different effects on hydrology and erosion of the three soils and discuss the primary reasons for these differences,and（iii） to understand the variations in real soil shear strength of the three soils during rainfall events and mathematically model the effects of the crusts on soil *** study showed that the soil crusts delayed the onset of infiltration by 5 to 15 min and reduced the total amount of infiltration by 42.9 to 53.4%during rainfall *** a purple soil and a loess soil,the initial crust increased the runoff by 2.8%and 3.4%,respectively,and reduced the splash erosion by 3.1%and 8.9%,*** a black soil,the soil crust increased the runoff by 42.9%and unexpectedly increased the splash erosion by 95.2%.In general,the effects of crusts on the purple and loess soils were similar and negligible,but the effects were significant for the black *** soil shear strength decreased dynamically and gradually during the rainfall events,and the values of crusted soils were higher than those of incrusted soils,especially during the early stage of the *** models were developed to describe the effects of soil crusts on the splash erosion for the three soils as follows:purple soil,F;=0.002?-0.384;black soil,F;=-0.022?+ 3.060;and loess soil,F;.= *** with the equation R;=F;·(R;-1).the splash erosion of the crusted soil can be predicted over time.

关键词： Physical soil crusts Hydrology Splash erosion Effects Shear strength

Catalytic Asymmetric Synthesis of Axially Chiral 3,3'-Bisindoles by Direct Coupling of Indole Rings

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Chinese Journal of Chemistry 2022年第18期40卷 2151-2160页

作者： feng-Tao Sheng Shuang yang Shu-Fang wu Yu-Chen Zhang feng Shi School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhouJiangsu221116 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China

Comprehensive Summary A new strategy for the enantioselective synthesis of axially chiral 3,3'-bisindoles was devised by the direct coupling of two indole *** strategy makes use of the C3-umpolung reactivity of 2-indolylmethanols,which enables the catalytic asymmetric addition reaction of 2-indolylmethanols with rationally designed 2-substituted indoles,thus constructing axially chiral 3,3'-bisindole scaffolds in overall excellent yields(up to 98%)with high enantioselectivities(up to 96:4 er).This approach not only has overcome the challenges in constructing axially chiral five-five-membered heterobiaryls,but also represents a new application of the C3-umpolung reactivity of 2-indolylmethanols in asymmetric *** importantly,this class of axially chiral 3,3'-bisindoles can undergo a variety of post-functionalizations to give axially chiral 3,3'-bisindole-based organocatalysts,which have found their preliminary applications in asymmetric catalysis.

关键词： Asymmetric catalysis Atroposelectivity Axial chirality Organocatalysis Enantioselectivity

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电线电缆绝缘电阻测量及影响因素分析

工程建设与设计 2017年第20期 37-39页

作者：乔文玮冯国五杨恒勇夏迪星江苏华能电缆股份有限公司江苏高邮225613

在电力的运行过程中,电线电缆的绝缘电阻决定着其自身的绝缘等级,通过测量电线电缆的电阻值可以准确地判断出其绝缘程度,并根据不同的情况进行科学的安排,但是测量电线电缆的电阻受到许多因素的影响,论文通过多方面的分析,提出相应的解... 详细信息

在电力的运行过程中,电线电缆的绝缘电阻决定着其自身的绝缘等级,通过测量电线电缆的电阻值可以准确地判断出其绝缘程度,并根据不同的情况进行科学的安排,但是测量电线电缆的电阻受到许多因素的影响,论文通过多方面的分析,提出相应的解决措施。

关键词：电线电缆绝缘电阻测量影响因素