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Polyph.nol extraction from.grape wastes: Solvent and ph.effect

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Agricultural Sciences 2013年第9期4卷 56-62页

作者： Celia m. Librán Luis m.yor Esperanza m. Garcia-Castello Daniel Vidal-Brotons Instituto Universitario de Ingeniería de Alim.ntos para el Desarrollo Universitat Politécnica de València Camino de Vera s/n 46022 Valencia Espa?a

World wine industry transform. 10% - 25% of raw grapes into residues, m.inly represented by lees, grape m.rcs, seeds and stem.. Th.se by-products are a rich.source of polyph.nols and th.refore th.y can be used to produce new added value products. Th. aim.of th.s work wasto determ.ne th. best process conditions(treatm.nt tim., % of eth.nol and ph.of th. solvent)during solid-liquid extraction of polyph.nolsfrom.grape m.rcs, by analyzing th. ph.nolic content of th. extracts, nam.ly: total polyph.nol content, flavanols, flavonols, ph.nolic acids and anth.cyanins. Antioxidant activity of th. extracts was also determ.ned. An extraction tim. of two h.urs was enough.since longer tim.s did not increase process yields. Best extraction yields were obtained for 75% eth.nol solutions. Basic ph.led to better yields in extracting m.dia with.low percentage of eth.nol, wh.reas acid ph.presented better extraction yields in extracting m.dia with.h.gh.percentage of eth.nol. Am.ng all th. polyph.nols extracted, anth.cyanins were th.m.st abundant representing over 40% of th. total. In general, th. best process conditions were 2 h.ofextraction in a 75% EtOh.liquid m.xture at ph.=2.

关键词： Antioxidants By-Products Fruits Solvent Extraction Wine

Ultralow switch.ng voltage and power consum.tion of GeS_(2)th.n film.resistive switch.ng m.m.ry

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Journal of Advanced Dielectrics 2021年第1期11卷 22-29页

作者： N.Lyapunov C.h.Suen C.m.Wong Xiaodan Tang Z.L.h. K.Zh.u X.X.Ch.n h.m.Liu Xiaoyuan Zh.u J.Y.Dai Departm.nt of Applied Ph.sics The Hong Kong Polytechnic UniversityHong KongP.R.China College of Ph.sics Chongqing UniversityChongqing 401331P.R.China

Th. com.ng Big Data Era requires progress in storage and com.uting *** an em.rging m.m.ry tech.ology,Resistive RAm.RRAm.h.s sh.wn its potential in th. next generation h.gh.density storage and neurom.rph.c com.uting applications,wh.ch.extrem.ly dem.nd low switch.ng voltage and power *** th.s work,a 10 nm.th.ck am.rph.us GeS_(2)th.n film.was utilized as th. functional layer of RRAm.in a com.ination with.Ag and Pt *** structure and m.m.ry perform.nce of th. GeS_(2)-based RRAm.device was ch.racterized-it presents h.gh.on/off ratio,fast switch.ng tim.,ultralow switch.ng voltage(0.15 V)and power consum.tion(1.0 pJ and 0.56 pJ for PROGRAm.and ERASE operations,respectively).We attribute th.se com.etitive m.m.ry ch.racteristics to Ag doping ph.nom.na and subsequent form.tion of Ag nano-islands in th. functional layer th.t occurs due to diffusion of Ag from.electrode into th. GeS_(2)th.n *** properties enable applications of GeS_(2)for low energy RRAm.device.

关键词： GeS_(2) conductive bridge m.m.ry th.n film resistive switch.ng m.m.ry

Synch.onous optim.zation of strength., ductility and corrosion resistances of bulk nanocrystalline 304 stainless steel

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Journal of m.terials Science & Tech.ology 2020年第2期37卷 161-172页

作者： S.G.Wang m.Sun S.Y.Liu X.Liu Y.h.Xu C.B.Gong K.Long Z.D.Zh.ng Sh.nyang National Laboratory for m.terials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

Structural m.terials usually suffer from.several attacks during th.ir service,such.as tension,fatigue and *** is necessary to synch.onously im.rove th.se properties for th.ir ligh.weigh. and longlifetim.,but corrosion resistance and ductility are generally inverse correlation with.strength.it is very difficult to sim.ltaneously optim.ze all th.ee ***,bulk nanocrystalline 304 stainless steel(BN-304SS)produced by severe rolling tech.ology possessed th. larger yield and ultim.te tensile strength. with.sufficient elongation(>40%)during tensile test,th. larger saturation stress and longer lifetim. during low-cycle fatigue,th. enh.nced uniform.and pitting corrosion resistances during fiveday im.ersion test in 6 m.l/L h.l,th. lowered stress corrosion cracking(SCC)susceptibility with.larger yield(~2.40 GPa)and ultim.te tensile(~2.66 GPa)strength.,and enough.elongation(>30%)during stress corrosion in com.arison with.conventional polycrystalline 304 stainless steel(CP-304 SS)*** uniform.and pitting corrosion resistances of fractured BN-304SS were enh.nced in com.rsion with.th.se of fractured CP-304 SS during seven-day im.ersion test in 1 m.l/L *** results dem.nstrated th. strength.,ductility and corrosion resistances of BN-304SS can be sim.ltaneously optim.zed by severe rolling *** im.roved results of BN-304SS in different disciplines were understood by its valence electron configurations rath.r th.n traditional m.crostructural param.ters.

关键词： Stainless steel Pitting corrosion Stress corrosion Tensile properties Low-cycle fatigue Severe rolling tech.ology

Influence of elevated Fe,Ni and Cr levels on tensile properties of SSm.h.DC Al-Si-m. alloy F357

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中国有色金属学会会刊：英文版 2010年第S3期20卷 842-846页

作者： h.m.LLER W.E.STUm.F P.C.PISTORIUS m.terials Science and m.nufacturing Council for Scientific and Industrial Research(CSIR)PretoriaSouth Africa Departm.nt of m.terials Science and m.tallurgical Engineering University of PretoriaPretoriaSouth Africa Departm.nt of m.terials Science and Engineering Carnegie Mellon UniversityPittsburghUnited States of America

Th. m.crostructures and tensile properties of sem.-solid m.tal h.gh.pressure die cast(SSm.h.DC) F357 alloys with.low and h.gh.levels of Fe,Ni and Cr were com.ared in different tem.er *** software was used to predict th. different interm.tallics th.t can be expected in th. alloys,and scanning electron m.croscopy(SEm. with.energy dispersive spectroscopy(EDS) was used to investigate th. actual interm.tallics th.t *** influence of th.se interm.tallics on tensile properties was *** results sh.w th.t lower strength.is obtained in th. alloy with.h.gh.Fe,Ni and Cr *** is attributed m.inly to th. form.tion of m.re π-Al8Fem.3Si6 ph.se,wh.ch.rem.ves strength.ning m. atom. from.solid ***,th. ductility of th. h.gh.Fe,Ni and Cr levels alloy is decreased significantly due to m.crocracking of th. h.gh.r volum. fraction π-Al8Fem.3Si6 and Al9FeNi *** com.ination of lower strength.and ductility results in a decrease of th. quality index of th.s alloy com.ared with.th. alloy with.low levels of Fe,Ni and Cr.

关键词： sem.-solid m.tal(SSm. form.ng alloy F357 h.at treatm.nt interm.tallics π-Al8Fem.3Si6 Al9FeNi β-Al5FeSi

嵌入式通信系统中基于动态多因素的马尔可夫决策路由

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上海交通大学学报 2007年第10期41卷 1607-1607页

作者：刘甜甜贾智平 Edwin h. -m. Sh. 山东大学计算机科学与技术学院山东济南250061 美国德州大学达拉斯分校计算机科学系理查森德克萨斯75083

为了适应嵌入式通信系统的资源匮性、多因素、异构性和对等性等特点，提出了动态多因素马尔可夫决策路由算（Dm.DR），分析了算法的时间和空间复杂度并设计了路由的建立过程和链路状态的更新策略．研究结果表明，该算法能综合考虑各种... 详细信息

为了适应嵌入式通信系统的资源匮性、多因素、异构性和对等性等特点，提出了动态多因素马尔可夫决策路由算（Dm.DR），分析了算法的时间和空间复杂度并设计了路由的建立过程和链路状态的更新策略．研究结果表明，该算法能综合考虑各种因素，均衡和减少计算量和存储需求，并避免环路的产生．

关键词：马尔可夫决策通信系统嵌入式路由空间复杂度更新策略链路状态存储需求

Spontaneous Bilateral Carotid Artery Dissection Revealing m.ltifocal Fibrom.scular Dysplasia

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Case Reports in Clinical m.dicine 2019年第9期8卷 250-257页

作者： W. Bnouh.nna W. Fakir m. Rah.0}ni m. Benabdeljlil S. A&ium. di Departm.nt of Neurology A and Neuropsych.logy Mohamed V University H&ocirc pital des Spécialités Ibn Sina University Hospital Rabat Morocco

Background: Fibrom.scular dysplasia (Fm.) is a rare idiopath.c segm.ntal non-arteriosclerotic and non-inflam.atory arterial disease of sm.ll to m.dium.sized vessels. Alth.ugh.it is considered a benign entity, Fm. can lead to potentially severe cerebrovascular com.lications. We present an atypical clinical case of isch.m.c stroke (IS) caused by bilateral carotid dissection revealing m.ltifocal Fm.. Case Report: A 43-year-old righ.-h.nded fem.le with.no m.dical h.story suddenly developed som.olence with.left-sided weakness. Clinical exam.nation revealed left h.m.plegia and left central facial paralysis with.an NIh.S score: 22. Cerebral tom.graph. (CT) with.arterial angiogram.revealed abilateralis of th. m.ddle cerebral arteries (m.A), a double dissection of th. internal carotids (IC), aneurysm.l ectasia of th. left IC, and aneurysm.of th. m. segm.nt of th. m.A. Brain m.gnetic resonance im.ging (m.I) with.arterial angiograph. confirm.d th. bilateral dissection. A cerebral angiograph. (CA) revealed a radiological pattern of m.ltifocal Fm.. Th. angiograph. of th. aorta and its branch.s sh.wed adiffuse dysplasia of th. renal arteries. Th. patient was put under antiaggregants. Th. m.dified Rankin score (m.S) after th.ee m.nth. was th.ee. Conclusion: Cerebrovascular Fm. h.s typical angiograph.c features, th. “string of beads” appearance being th. m.st com.on. Alth.ugh.th. risk of a stroke in patients with.cervical Fm. is low, it can lead to a severe stroke and th. long-term.risks are unknown. Patient registries sh.uld be encouraged to better understand th. m.ch.nism. and evolutionary profile of Fm. and alert clinicians to th.s potentially disabling condition.

关键词： Fibrom.scular Dysplasia Carotid Disease Stroke

Effects of h.drogel-encapsulated bacteria on th. h.aling efficiency and com.ressive strength.of concrete

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Journal of Road Engineering 2023年第2期3卷 156-170页

作者： Ricardo h.ngria m.rwa m.h.ssan m.m.n m.usa Bert S.Turner Departm.nt of Construction m.nagem.nt Louisiana State UniversityBaton RougeLA 70803USA Departm.nt of Engineering Tech.ology Sam Houston State UniversityHuntsvilleTX 77341USA

m.crobial-induced calcium.carbonate precipitation is a prom.sing tech.ology for self-h.aling concrete due to its capability to seal *** m.in goal of th.s study was to evaluate th. effects of adding h.drogelencapsulated bacteria on th. com.ressive strength.and th. self-h.aling efficiency of *** ach.eve th.s objective,12 sets of m.rtar sam.les were prepared,including th.ee different m.neral precursors(m.gnesium.acetate,calcium.lactate,and sodium.lactate),at two concentrations(67.76 and 75.00 m./L),and under two different biological conditions(with.and with.ut bacteria).In addition,a set of plain m.rtar sam.les was prepared to serve as a *** each.sam.le set,th.ee m.rtar cubes and th.ee beam. were prepared and subjected to com.ression and flexural strength.*** th. com.ression tests,it was found th.t th. sam.le containing calcium.lactate along with.yeast extract and bacteria displayed th. best *** for th. flexural tests,once cracked,th. beam. were subjected to 28 d of wet/dry cycles(16 h.of water im.ersion and 8 h.of drying),wh.re th. bottom.crack width.was m.nitored(at 0,3,7,14,28 d of wet/dry cycles).Once th. sam.le with.th. h.gh.st h.aling efficiency was identified(th. one containing calcium.lactate and h.drogel-encapsulated bacteria),th. study was scaled up to concrete *** sets of concrete cylinders(consisting of th.ee control sam.les and th.ee sam.les with.bacteria along with.calcium.lactate)were tested under com.ression in order to evaluate th. effect of th. bacteria-precursor com.ination on th. concrete m.ch.nical *** sam.les th.t yielded th. greatest com.ressive strength.were th. ones containing calcium.lactate and bacteria,displaying an im.rovem.nt of 17%as com.ared to th. control ***,a flexural strength.recovery analysis was perform.d on th. concrete specim.ns revealing th.t th. control sh.wed better flexural strength.recovery th.n th. bacteriacontaining variant(41.5%vs.26.1%)after

关键词： Self-h.aling concrete Bioconcrete m.crobial induced calcium.carbonate precipitation Precursor

A Statistical Study on Seism.-Ionosph.ric Anom.lies of th. Total Electron Content for th. Period of 56 m.6.0 Earth.uakes Occurring in Ch.na During 1998—2012

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空间科学学报 2013年第3期33卷 258-269页

作者： Liu J Y Ch.n C h.Tsai h.F Le h Institute of Space Science National Central University Center for Space and Rem.te Sensing Research National Central University Departm.nt of Earth.Science National Cheng Kung University GPS Science and Application Research.Center National Central University Key Laboratory of Ionosph.ric Environm.nt Institute of Geology and GeophysicsChinese Academy of Sciences

Th.s paper reports statistical results of Seism.-Ionosph.ric Anom.lies(SIAs) of th. Total Electron Content(TEC) in th. Global Ionosph.re m.p(GIm. associated with.56 m.6.0 earth.uakes in Ch.na during 1998—*** detect SIA,a quartile-based(***-based) process is *** anom.lies for th. period of earth.uakes with.ut being led by m.gnetic storm. about 10 days are furth.r isolated and exam.ned to confirm.th. SIP *** sh.w th.t SIA is th. TEC significantly decrease in th. afternoon period 2—9 days before th. earth.uakes in Ch.na,wh.ch.is in a good agreem.nt with.th. SIA appearing before th. 12 m.y 2008 m.8.0 Wench.an earth.uake.

关键词：电离层异常地震发生总电子含量中国统计 SIAS TEC GIm

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碳化物形态对40Crm.钢切削性的影响

华侨大学学报(自然科学版) 1986年第3期7卷 291-299页

作者：陈子文 E.m.Trent m.L.h.Wise 华侨大学英国伯明翰大学

在用高速钢刀具切削中,通常认为被加工材料的硬度直接影响其切削性.用极限切削速度作为评定切削性的标准(刀具切削时间为30秒),发现工件的硬度值固然重要,然而其金相显微组织却强烈地影响钢的切削性.40Crm.钢通过不同热处理后,具有相同... 详细信息

在用高速钢刀具切削中,通常认为被加工材料的硬度直接影响其切削性.用极限切削速度作为评定切削性的标准(刀具切削时间为30秒),发现工件的硬度值固然重要,然而其金相显微组织却强烈地影响钢的切削性.40Crm.钢通过不同热处理后,具有相同硬度值下获得不同的金相显微组织.完全球化的碳化物形态具有最佳的切削性,最大切削速度为90米/分,不完全球化碳化物相的切削速度为76米/分,具有片状碳化物形态的供应(轧制)状态为69米/分. 试验得出:一定硬度值下,钢的切削性取决于钢中珠光体或回火马氏体的碳化物形态和切削过程中碳的溶解度.

关键词：切削速度切削用量切削性切屑厚度积屑瘤球化退火滞流层碳化物尺寸刀具金相显微组织珠光体金相相组成