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Antimicrobial activities of methanolic extract of Carissa opaca roots and its fractions and compounds isolated from the most active ethyl acetate fraction

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Asian Pacific Journal of Tropical Biomedicine 2015年第7期5卷 533-537页

作者： Dildar Ahmed Ramsha Saeed Nasir Shakeel Khaizran Fatima Aneela Arshad Department of Chemistry Forman Christian College (A Chartered University) Microbiology lab Pharmagen Lahore Pakistan

Objective: To study the antibacterial and antifungal activities of methanolic extract of roots of Carissa opaca and its fractions in hexane, chloroform, ethyl acetate, n-butanol and water, and the isolated ***: The zones of inhibition of the samples against test microorganisms were determined by agar well diffusion method. Minimum inhibitory concentrations of the samples were determined by agar well dilution method. Test microorganisms included four standard bacteria [Bacillus subtilis ATCC 6633(B. subtilis), Escherichia coli ATCC 8739(E. coli), Pseudomonas aeruginosa ATCC 9027(P. aeruginosa), and Staphylococcus aureus ATCC 6538], two standard fungi [Candida albicans ATCC 10231(C. albicans)] and Aspergillus niger, and six clinical isolates(B. subtilis, E. coli, P. aeruginosa, Staphylococcus aureus, Salmonella typhi and Enterobacter cloacae). The most active fraction was investigated to isolate compounds. The chemical compounds isolated from the ethyl acetate fraction were identified by gas chromatography-mass spectrometer, high performance liquid chromatography and liquid chromatography-mass ***: E. coli, P. aeruginosa, and C. albicans were the most susceptible. Less polar fractions exhibited stronger efficacy than polar ones, and ethyl acetate fraction proved to be the most potent. Zones of inhibition of hexane, chloroform and ethyl acetate fractions, and amoxil against C. albicans were 19.96, 22.01, 23.10 and 19.20 mm, respectively. Ethyl acetate faction was the most toxic to all the test microorganisms, with minimum inhibitory concentrations of 8.0, 7.8 and 7.78 μg/m L against P. aeruginosa, C. albicans and B. subtilis, respectively. Isolated compounds, limonene, 2'-hydroxyacetophenone, vanillin, naphthalenone, 2,3,3-trimethyl-2-(3-methylbuta-1,3-dienyl)-6-methylenecyclohexanone, 2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester, β-sitosterol, vitamin E, rutin, quercetin, lupeol, epigallocatechin, showed considerable antimicrobia

关键词： Carissa opaca Antibacterial Antifungal Bioactive compounds

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Analytical-BEM coupling method for fast 3-D interconnect resistance extraction

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Frontiers of Electrical and Electronic Engineering in China 2006年第2期1卷 239-243页

作者： WANG Xi-ren YU Wen-jian WANG Ze-yi EDA lab Dept.Computer Science and technologyTsinghua UniversityBeijing 100084China

Deep submicron process technology is widely being used and interconnect structures are becoming more and more *** means that the resistance calculation based on two-dimensional models can no longer provide sufficiently accurate *** paper presents a three-dimensional resistance calculation method called the combined analytical formula and boundary element method(ABEM).The method cuts selected interconnecting lines then it calculates the resistances of straight sections using an analytical formula and the resistances of the other sections using the boundary element method(BEM).The resistances of the different sub-regions are combined to calculate the resistance of the entire *** on actual layouts show that compared with the commercial software Raphael based on finite difference method,the proposed method is 2-3 orders of magnitude *** ABEM method uses much less memory(about 0.1%-1%),and is more accurate than Raphael with default mesh *** results illustrate that the proposed method is efficient and accurate.

关键词： Very large scale integration Interconnecting resistance 3-D extraction Analytical formula BEM

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In situ compression and X-ray computed tomography of flow battery electrodes

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Journal of Energy Chemistry 2018年第5期27卷 1353-1361页

作者： Rhodri Jervis Matt D.R.Kok Tobias P.Neville Quentin Meyer Leon D.Brown Francesco Iacoviello Jeff T.Gostick Dan J.L.Brett Paul R.Shearing Electrochemical Innovation lab Department of Chemical Engineering University College London Department of Chemical Engineering McGill University Porous Media Engineering and Analysis lab Department of Chemical Engineering University of Waterloo

Redox flow batteries offer a potential solution to an increase in renewable energy generation on the grid by offering long-term, large-scale storage and regulation of power. However, they are currently un- derutilised due to cost and performance issues, many of which are linked to the microstructure of the porous carbon electrodes used. Here, for the first time, we offer a detailed study of the in situ effects of compression on a commercially available carbon felt electrode. Visualisation of electrode structure us- ing X-ray computed tomography shows the non-linear way that these materials compress and various metrics are used to elucidate the changes in porosity, pore size distribution and tortuosity factor under compressions from 0%-90%.

关键词： Redox flow battery X-ray computed tomography Compression Carbon felt RFB

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Aspects of Antithrombotic Effect of HMG-CoA Reductase Inhibitors

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血栓与止血学 2005年第1期11卷 3-4页

作者：贺石林 Hemostasis Physiology lab

Statins, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors are widely used for the treatment of hypercholesteremia and have showed remarkable activity in preventing cardiovascular morbidity and mortality. Recent studies demonstrated that statins have significant antithrombotic effect in addition to cholesterollowering action. Although the efficacy of statins for reducing cardiovascular events has historically been ascribed to their inhibitory activity on cholesterol synthesis, the degree of low-density lipoprotein cholesterol reduction by statins generally does not correlate with the magnitude of coronary risk reduction.

关键词：抗血栓形成还原酶抑制剂预防治疗

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Mining the rank of universities with Wikipedia

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Science China(Information Sciences) 2019年第10期62卷 200-202页

作者： Zongjian LI Cong LI Xiang LI Adaptive Networks and Control lab Department of Electronic EngineeringFudan University Research Center of Smart Networks and Systems School of Information Science EngineeringFudan Univeristy

Dear editor,Wikipedia is a free-access and web-based multilingual encyclopedia that voluntaries from all around the world can write and edit. Previous studies on Wikipedia mainly focused on its collaborative systems, i.e., edit patterns [1, 2]. Besides the relation network of editors in Wikipedia, the articles of Wikipedia form a large-scale complex network, the Wikipedia article reference network(WARN). Articles are regarded as nodes, which

关键词： red net No Mining the rank of universities with Wikipedia

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用于高效电磁波吸收的3D打印超材料

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Science China Materials 2023年第4期66卷 1283-1312页

作者：周睿于震吴蓁蓁曲畅宋燕邢瑞哲孔杰 Shaanxi Key lab of Macromolecular Science and Technology MOE Key Lab of Materials Physics and Chemistry in Extraordinary ConditionsSchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

由人工结构组成的超材料具有传统材料不具备的卓越性能.通过设计和排列具有特殊物理性质的单元结构可制备用于高效电磁波吸收的吸波超材料.这些亚波长尺度的单元结构是吸波超材料超越传统材料性能极限的基础,因此制造工艺的匹配尤为重要... 详细信息

由人工结构组成的超材料具有传统材料不具备的卓越性能.通过设计和排列具有特殊物理性质的单元结构可制备用于高效电磁波吸收的吸波超材料.这些亚波长尺度的单元结构是吸波超材料超越传统材料性能极限的基础,因此制造工艺的匹配尤为重要.快速发展的3D打印技术在制造具有复杂结构的材料方面展现出巨大的优势和潜力,为研究和制备吸波超材料提供了一种简单、快速、高效的方法.在这篇综述中,我们介绍了吸波超材料的概念和发展,重点介绍了利用3D打印技术制造吸波超材料的研究现状.此外,还简要介绍了超材料的典型应用,讨论了当前超材料发展的不足和3D打印技术制备吸波超材料的局限性,并提出了超材料和3D打印技术结合的发展前景.

关键词：电磁波吸收单元结构超材料典型应用制造工艺性能极限发展前景亚波长

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Thermally activated flux flow,vortex-glass phase transition and the mixed-state Hall effect in 112-type iron pnictide superconductors

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Science China(Physics,Mechanics & Astronomy) 2018年第12期61卷 45-52页

作者： XiangZhuo Xing ZhanFeng Li XiaoLei Yi JiaJia Feng ChunQiang Xu Nan Zhou Yan Meng YuFeng Zhang YongQiang Pan LingYao Qin Wei Zhou HaiJun Zhao ZhiXiang Shi School of Physics and Key laboratory of MEMS of the Ministry of Education Southeast UniversityNanjing 211189China Advanced Functional Materials lab and Department of Physics Changshu Institute of TechnologyChangshu 215500China

The transport properties in the mixed state of high-quality Ca_(0.8)La_(0.2)Fe_(0.98)Co_(0.02)As_2single crystal,a newly discovered 112-type iron pnictide superconductor,are comprehensively studied by magneto-resistivity *** field-dependent activation energy,U_0,is derived in the framework of thermally activated flux flow(TAFF)theory,yielding a power law dependence U_0～H~αwith a crossover at a magnetic field around 2 T in both H⊥ab and H//ab,which is ascribed to the different pinning ***,we have clearly observed the vortex phase transition from vortex-glass to vortex-liquid according to the vortex-glass model,and vortex phase diagrams are constructed for both H⊥ab and H//***,the results of mixed-state Hall effect show that no sign reversal of transverse resistivityρ_(xy)(H)is detected,indicating that the Hall component arising from the vortex flow is in theories or experiments previously reported on some high-T_ccuprates.

关键词： thermally activated flux flow vortex-glass transition mixed-state Hall effect 112-type iron pnictide superconductors

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Preparation and Characterization of Chitosan/β-GP Membranes for Guided Bone Regeneration

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Journal of Wuhan University of Technology(Materials Science) 2011年第2期26卷 242-246页

作者：崔军徐欣孙康宁 Department of Dental Implant Center School of StomatologyShandong University Shandong Provincial Key lab Dral Biomedicine School of Materials Science and Engineering Shandong University

Bioabsorbable chitosan/β-glycerol phosphate （CS/β-GP） composite membranes were fabricated through a relatively PH neutral and mild sol-gel process for guided bone regeneration （GBR）.Their structural properties,morphology,and tensile strength were *** and XRD analyses indicated that there were chemical bonds between the CS andβ-*** analysis revealed that the CS/β-GP composite membranes had a porous structure both at the surface and in *** though the incorporation ofβ-GP in the CS matrix decreased the initial tensile strength of the membrane,the CS/β-GP membranes were still fit for GBR application with their tensile strength of roughly *** concentration ofβ-GP was proportional to the pore size and thickness but was inversely proportional to the tensile strength of the CS/β-GP *** present findings indicate that,based on its characteristics,the CS/β-GP composite membrane is a potential bioresorbable membrane for use in guided bone regeneration.

关键词： chitosan β-glycerol phosphate guided bone regeneration membrane thermo-sensitive hydrogel

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The Influence of Element Diffusion at the Sediment-Water Interface on the Basic Chemical Composition of Overlying Water Mass in Lake Lugu, China

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Chinese Journal Of Geochemistry 1996年第3期15卷 285-288页

作者：吴丰昌方国江蔡玉蓉 State Key lab. of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang

Little work has been done on the influence of sediments on the basic chemical composition of overlying water mass. This paper deals with the vertical profile of the basic constituents such as Ca2 +, K +, Na+, and HCO3, as well as of pH in the overlying water mass and sediment porewater of Lake Lugu-a semi-closed, deep lake in Yunnan Province. The results revealed that those basic constituents may diffuse and transport from bottom sediments to overlying water mass through porewater. In the paper are also quantitatively evaluated the diffusive fluxes and the extent of their influence on overlying water mass, indicating that the lake sediment-water interface diffusion plays an important role in controling the basic chemical composition of water in the whole lake.

关键词：元素扩散沉积物-水界面湖泊云南 PH值表面化学泸沽湖钙离子钾离子水团

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Tribological Mechanism of Graphene and Ionic Liquid Mixed Fluid on Grinding Interface under Nanofluid Minimum Quantity Lubrication

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 79-96页

作者： Dexiang Wang Yu Zhang Qiliang Zhao Jingliang Jiang Guoliang Liu Changhe Li School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdaoChina Key lab of Industrial Fluid Energy Conservation and Pollution Control(Qingdao University of Technology) Ministry of EducationQingdaoChina

Graphene has superhigh thermal conductivity up to 5000 W/(m·K),extremely thin thickness,superhigh mechanical strength and nano-lamellar structure with low interlayer shear strength,making it possess great potential in mini-mum quantity lubrication(MQL)***,ionic liquids(ILs)have higher thermal conductivity and better thermal stability than vegetable oils,which are frequently used as MQL grinding *** ILs have extremely low vapor pressure,thereby avoiding film boiling in *** excellent properties make ILs also have immense potential in MQL ***,the grinding performance of graphene and ionic liquid mixed fluid under nano-fluid minimum quantity lubrication(NMQL),and its tribological mechanism on abrasive grain/workpiece grinding interface,are still *** research firstly evaluates the grinding performance of graphene and ionic liquid mixed nanofluids(graphene/IL nanofluids)under NMQL *** evaluation shows that graphene/IL nanofluids can further strengthen both the cooling and lubricating performances compared with MQL grinding using ILs *** specific grinding energy and grinding force ratio can be reduced by over 40%at grinding depth of 10μ***-piece machined surface roughness can be decreased by over 10%,and grinding temperature can be lowered over 50℃at grinding depth of 30μ*** at the unclear tribological mechanism of graphene/IL nanofluids,molecular dynamics simulations for abrasive grain/workpiece grinding interface are performed to explore the formation mechanism of physical adsorption *** simulations show that the grinding interface is in a boundary lubrication *** molecules absorb in groove-like fractures on grain wear flat face to form boundary lubrication film,and graphene nanosheets can enter into the grinding interface to further decrease the contact area between abrasive grain and *** with MQL grinding,the average tangential grinding force of graphene/IL nanof

关键词： Grinding Nanofluid minimum quantity lubrication Graphene Tribological mechanism

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