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High-permeance crosslinked PTMsP thin-film composite membranes as supports for CO_2 selective layer formation

Green Energy & Environment 2016年第3期1卷 235-245页

作者： stepan D.Bazhenov Ilya L.Borisov Danila s.Bakhtin Anastasia N.Rybakova Valery s.Khotimskiy sergey P.Molchanov Vladimir V.Volkov A.V.Topchiev Institute of Petrochemical synthesis RAS

In the development of the composite gas separation membranes for post-combustion CO_2 capture, little attention is focused on the optimization of the membrane supports, which satisfy the conditions of this technology. The primary requirements to the membrane supports are concerned with their high CO_2 permeance. In this work, the membrane supports with desired characteristics were developed as high-permeance gas separation thin film composite(TFC) membranes with the thin defect-free layer from the crosslinked highly permeable polymer, poly[1-(trimethylsilyl)-1-propyne](PTMsP). This layer is insoluble in chloroform and can be used as a gutter layer for the further deposition of the CO_2-selective materials from the organic solvents. Crosslinking of PTMsP was performed using polyethyleneimine(PEI) and poly(ethyleneglycol) diglycidyl ether(PEGDGE) as crosslinking agents. Optimal concentrations of PEI in PTMsP and PEGDGE in methanol were selected in order to diminish the undesirable effect on the final membrane gas transport characteristics. The conditions of the kiss-coating technique for the deposition of the thin defect-free PTMsP-based layer, namely, composition of the casting solution and the speed of movement of the porous commercial microfiltration-grade support, were optimized. The procedure of post-treatment with alcohols and alcohol solutions was shown to be crucial for the improvement of gas permeance of the membranes with the crosslinked PTMsP layer having thickness ranging within 1-2.5 μm. The claimed membranes showed the following characteristics: CO_2 permeance is equal to 50—54 m^3(sTP)/(m^2 h bar)(18,500—20,000 GPU), ideal CO_2/N_2 selectivity is 3.6-3.7, and their selective layers are insoluble in chloroform. Thus, the developed highpermeance TFC membranes are considered as a promising supports for further modification by enhanced CO_2 selective layer formation.

关键词： Thin-film composite membrane Gas permeance PTMsP Crosslinking Carbon dioxide capture

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The effect of carbon nanotubes and polypropylene fibers on bond of reinforcing bars in strain resilient cementitious composites

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Frontiers of structural and Civil Engineering 2016年第2期10卷 214-223页

作者： souzana P. TAsTANI Maria s. KONsTA-GDOUTOs, stavroula J. PANTAZOPOULOU Victor BALOPOULOs Department of Civil Engineering Democritus University oJ Thrace Vas. Sofias Street #12 Xanthi 67100 Greece

stress transfer between reinforcing bars and concrete is engaged through rib translation relative to concrete, and comprises longitudinal bond stresses and radial pressure. The radial pressure is equilibrated by hoop tension undertaken by the concrete cover. Owing to concrete＇s poor tensile properties in terms of strength and deformability, the equilibrium is instantly released upon radial cracking of the cover along the anchorage with commensurate abrupt loss of the bond strength. Any improvement of the matrix tensile properties is expected to favorably affect bond in terms of strength, resilience to pullout slip, residual resistance and controlled *** aim of this paper is to investigate the local bond of steel bars developed in adverse tensile stress conditions in the concrete cover. In the tests, the matrix comprises a novel, strain resilient cementitious composite （sRCC） reinforced with polypropylene fibers （PP） with the synergistic action of carbon nano-tubes （CNT）. Local bond is developed over a short anchorage length occurring in the constant moment region of a four-point bending short beam. Parameters of investigation were the material structure （comprising a basic control mix, reinforced with CNTs and/or PP fibers） and the age of testing. Accompanying tests used to characterize the cementitious material were also conducted. The test results illustrate that all the benefits gained due to the synergy between PP fibers and CNTs in the matrix, namely the maintenance of the multi-cracking effect with time, the increased strength and deformability as well as the highly increased material toughness, were imparted in the recorded bond response. The local bond response curves thus obtained were marked by a resilient appearance exhibiting sustained strength up to large levels of controlled bar-slip; the elasto-plastic bond response envelope was a result of the confining synergistic effect of CNTs and the PP fibers, and it occurred even without bar yielding.

关键词： carbon nanotubes strain resilient cementitious composite polypropylene fibers tensile bending bond

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Migration departure strategies of shorebirds at a final pre-breeding stopover site

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Avian Research 2018年第3期9卷 188-197页

作者： Kun Tan Chi-Yeung Choi Hebo Peng David s.Melville Zhijun Ma Ministry of Education Key Laboratory for Biodiversity science and Ecological Engineering Institute of Biodiversity ScienceFudan UniversityShanghai 200433China Centre for Integrative Ecology Deakin UniversityGeelongVICAustralia NIOZ Royal Netherlands Institute for sea Research Department of Coastal Systems and Utrecht UniversityP.O.Box 591790 AB Den BurgTexelThe Netherlands Global Flyway Ecology Conservation Ecology GroupGroningen Institute for Evolutionary Life Sciences(GELIFES)University of GroningenP.O.Box 111039799 CC GroningenThe Netherlands Nelson New Zealand

Background: Departure decisions and behaviors of migratory birds at stopover sites are expected to maximize fit?ness by trade?offs among avoiding predators, optimizing refueling(energy) capacity, and matching other life?history events. We predict that species with different body sizes and migratory destinations will exhibit different behaviors when departing from the same stopover site. We also predict that with strong time constraint at the final pre?breed?ing stopover site, departure decisions may be less sensitive to exogenous factors, such as wind condition, compared to other stopover or nonbreeding ***: We recorded migratory departures of four shorebird species, i.e. Eurasian Curlew(Numenius arquata), bar?tailed Godwit(Limosa lapponica), Great Knot(Calidris tenuirostris), and Grey Plover(Pluvialis squatarola), at Yaluji?ang Estuary Wetlands in China, a final pre?breeding stopover site in the northern Yellow sea, from 2011 to 2014. We compared flock sizes, departure time and departure directions between species, and investigated the effects of tide and weather conditions(rain and ground wind speed and direction) on the departure decision of ***: We found that larger species departed in smaller flocks and were more variable in daily departure time. Departure trajectory of all four species appeared to be influenced by coastal topography. With the east–west coast?line and intertidal mudflat on the south, birds exhibited westward or eastward deflection from the shortest migra?tory routes. bar?tailed Godwit was the only species that deviated to the southeast and did not climb over the land. Birds avoided departure during precipitation, while their departure was not related to ground wind benefit or tidal ***: Body size among species, which influences their vulnerability to predators, might be important in shaping shorebird departure strategies. Diverse departure directions could be the result of different wind use tac?tics i

关键词： Migration Departure decision Departure behavior shorebird stopover Wader East Asian-Australasian Flyway

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Induction motors variable speed drives diagnosis through rotor resistance monitoring

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Frontiers in Energy 2012年第4期6卷 420-426页

作者： K. YAHIA s. ZOUZOU F. BENCHABANE GEB Laboratory Department of Electrical Engineering University ofBiskra BP 145 Biskra Algeria MsE Laboratory Department of Electrical Engineering University ofBiskra BP 145 Biskra Algeria

Induction motor driven by vector control method makes high performance control of torque and speed possible. The decoupling of flux and electromag netic torque obtained by field orientation depends on the precision and the accuracy of the estimated states. Rotor asymmetries lead to perturbations of air gap flux patterns in induction machines. These perturbations in flux compo nents affect the electromagnetic torque, as well as stator currents and voltages. This paper first investigates the control of the induction motor using an extended Kalman filter （EKF） for a direct fieldoriented control. It then studies the broken rotor bars （BRBs） fault by the monitoring the rotor resistance. The hypothesis on which the detection is based is that the apparent rotor resistance of the motor will increase when a rotor bar breaks. The rotor resistance is estimated and value to detect BRBs fault. compared with its nominal The EKF estimates the rotor flux, speed and rotor resistance on line by using only measurements of the stator voltages and currents. simula tion results show the effectiveness of the proposed method in the cases of load torque perturbation and speed reversion.

关键词： induction motor vector control broken rotorbars (BRBs) diagnostic extended Kalman filter (EKF)

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Wave Interaction with an Emerged Porous Media

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Advances in Applied Mathematics and Mechanics 2014年第5期6卷 680-692页

作者： I.Magdalena s.R.Pudjaprasetya L.H.Wiryanto Industrial&Financial Mathematics Research Group Faculty of Mathematics and Natural SciencesInstitut Teknologi BandungIndonesiaJalan Ganesha 10BandungWest JavaIndonesia

In this paper,we study wave interaction with an emerged porous *** governing equation is shallow water equations with a friction term of the linearized Dupuit-Forcheimer’s *** the continuity of surface and horizontal flux,we derived the wave reflection and transmission coefficient *** are similar with the corresponding formulas of the submerged solid bar *** solve the equations numerically using finite volume method on a staggered *** numerical wave reduction in the porous media confirms the analytical wave transmission curve.

关键词： Emerged porous media shallow water equation wave transmission coefficient wave reflection coefficient

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施工高温作用后CFRP板增强桥梁疲劳损伤及寿命预测（英文）

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中国公路学报 2016年第6期29卷 221-231页

作者：袁鑫 DABNATH s K 郑伟苏州科技大学土木工程学院江苏苏州215011 东南大学土木工程学院江苏南京210096 达卡工程技术大学土木工程学院苏州中固建筑科技有限公司江苏苏州215152

为了探讨碳纤维增强塑料(CFRP)板在沥青摊铺高温环境下加固国外大桥中的疲劳损伤机理及寿命预测,首先介绍Bangabandhu大桥在孟加拉国亚热带湿热环境温度下进行沥青玛蹄脂新桥面铺装的高温加固环境,然后通过钢筋、混凝土和CFRP板应变等... 详细信息

为了探讨碳纤维增强塑料(CFRP)板在沥青摊铺高温环境下加固国外大桥中的疲劳损伤机理及寿命预测,首先介绍Bangabandhu大桥在孟加拉国亚热带湿热环境温度下进行沥青玛蹄脂新桥面铺装的高温加固环境,然后通过钢筋、混凝土和CFRP板应变等参数研究大桥箱梁桥顶板增强梁疲劳裂纹演化、荷载-挠度曲线变化规律及CFRP板应力情况,对梁体抗裂性、刚度和疲劳损伤累积进行分析;最后,根据疲劳裂纹扩展规律和破坏模式,结合试验结果,采用相应的断裂力学分析模型,引入裂纹尖端的应力强度因子计算公式,对试件进行疲劳主裂纹扩展研究。研究结果表明:在沥青摊铺高温作用下,CFRP板仍可以有效抑制混凝土的开裂和裂缝发展,经过CFRP板加固的钢筋混凝土试验梁疲劳寿命有一定提高,经过沥青摊铺高温作用后的CFRP板加固试验梁仍可满足200万次疲劳试验加载。通过da/dN-ΔK曲线和裂纹扩展速率进行疲劳寿命预测发现,该方法计算出的理论疲劳寿命与实际的疲劳寿命基本吻合。

关键词：桥梁工程 CFRP板疲劳试验损伤累积寿命预测施工高温桥梁增强

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Revalorization of CO2 for methanol production via ZnO promoted carbon nanofibers based Cu-ZrO2 catalytic hydrogenation

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Journal of Energy Chemistry 2019年第12期28卷 68-76页

作者： Israf Ud Din Maizatul s.shaharun A.Naeem s Tasleem Pervaiz Ahmad Department of Chemistry College of Science and HumaniriesPrince Sarttam bin Abdulaziz UniversityAl-kharjSaudi Arabia Department of Fundamental and Applied sciences Universiti Teknologi PETRONASMalaysia National Centre of Excellence in Physical Chemistry University of PeshawarPakistan Chemistry Department Kohat University of Science and TechnologyKohatPakistan Department of Physics University of Azad Jammu&Kashmir13100 MuzaffarabadPakistan

A series of novel carbon nanofibers(CNFs)based Cu-ZrO2 catalysts were synthesized by deposition precipitation *** investigate the influence of promoter,catalysts were loaded with 1,2,3 and 4 wt%ZnO and characterized by ICP-OEs,HRTEM,BET,N2O chemisorption,TPR,XPs and CO2-TPD *** results revealed that physicochemical properties of the catalysts were strongly influenced by incorporation of ZnO to the parent *** surface area(sCu)and dispersion(DCu)were slightly decreased by incorporation of ZnO ***,sCuand DCuwere remarkably decreased when ZnO content was exceeded beyond 3 wt%.The catalytic performance was evaluated by using autoclave slurry reactor at a pressure and temperature of 30 bar and 180℃,*** promotion of CuZrO2/CNFs catalyst with 3 wt%of ZnO enhanced methanol synthesis rate from 32 to 45 g kg^-1 h^-***,with the ZnO promotion the selectivity to methanol was enhanced to 92%compared to 78%of the un-promoted Cu-ZrO2/CNFs catalyst at the expense of a lowered CO2 *** addition,the catalytic activity of this novel catalyst system for CO2 hydrogenation to methanol was compared with the recent literature data.

关键词： Methanol synthesis slurry reactor Promoter effect Chemisorption studies CNFs CO2 conversion

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Experimental and Theoretical study of the Effect of Moisture on Methane Adsorption and Desorption by Activated Carbon at 273.5 K

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Journal of Natural Gas Chemistry 2007年第1期16卷 22-30页

作者： s.Farzad V.Taghikhani C.Ghotbi B.Aminshahidi E.Nemati Lay Department of Chemical and Petroleum Engineering Sharif University of TechnologyTehranIran

Adsorption and desorption of methane by activated carbon （AC） at constant temperature and at various pressures were investigated. The effect of moisture was also studied. A volumetric method was used, up to 40 bar, at a temperature of 273.5 K. Results of a dry AC sample were compared with those obtained from a moist sample and two different ACs with different physical and surface properties were used. As expected, the results showed that the existence of moisture, trapped in the AC pores, could lead to a decrease in the amount of methane adsorbed and a decrease in the amount of methane delivered during desorption. To model the experimental results, a large variety of adsorption isotherms were used. The regressed parameters for the adsorption isotherms were obtained using the experimental data generated in the present study. The accuracy of the results obtained from the different adsorption isotherms was favorably compared.

关键词： activated carbon adsorption adsorption properties thermodynamic analysis

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Calculation of solidification Process of Continuous Cast bar

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Journal of Harbin Institute of Technology(New series) 2014年第5期21卷 112-118页

作者： A I Golodnov R K Mysik A V sulitsin s V Brusnitsyn I A Gruzdeva Ural Federal University

In this paper,it presents the results of calculation of solidification process of copper continuous cast bar by cross section size 120 mm × 70 mm with application of Pro Cast 2010 software. The estimation of mould design effect on solidification process of continuos copper cast bar is completed at various speeds of *** of liquid metal cavities and temperature allocations in the cast bar at various casting speeds are *** analysis of received liquid metal cavity profiles shows that a new mold construction allows significantly decrease of the length of the liquid metal cavity during continuous copper casting at HAZELETTcasting machine and the increase of maximum casting speed from 10 to 11 m / min. Adequacy of the results of copper continuous cast bar solidification process calculation is confirmed by the experimental data.

关键词： continuous casting copper cast bar water cooling mold liquid metal cavity heat emission coefficient calculation of solidification process

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恩纳霜所致接触性荨麻疹

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世界核心医学期刊文摘（皮肤病学分册） 2005年第5期1卷 24-25页

作者： Waton J. Boulanger A. Trechot P.H. A.bar-baud serv.de 崔荣 Prof.Dermatol.Venereologle Hop.Maringer Villemin FournierC.H.U.Nancy36Quai de la Bataille54000-NancyFrance

We report the first case of immediate-type hypersensitivity caused by Emla. c ream. A 55-year-old woman, after using Emlacream, went on to develop urticar ia. An open test was positive to Emlacream. Patch tests and prick tests were p erformed with Emlacream, the components of Emlacream (lidocaine, prilocaine and castor oil) and other local anaesthetic s. The patch test with lidocaine and the prick test with Emlacream were both p ositive. An intradermal test and subcutaneous administration of 3 anaesthetics t hat had negative patch tests and prick tests were performed and well tolerated,a llowing their use. In the literature, anaphylactic reactions to lidocaine inject ions, delayed-type hypersensitivity after lidocaine subcutaneous injections and contact dermatitis from Emlacream have all been described. This first case of contact urticaria from Emlacream was due to lidocaine and did not show any cr oss-reaction with other local anaesthetics.

关键词：接触性荨麻疹恩纳斑贴试验皮内试验针刺试验多卡因局部麻醉药开放试验迟发型超敏反应文献报道

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