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CONDUCTIVe.COmPOSITe. FROm POLYPYRROLe.e.e.TROPOLYme.IZe. IN A POLYURe.HANe.mATRIX

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Chine.e.Journal of Polyme. Scie.ce 1990年第2期8卷 149-157页

作者：宝净生 m. L. DAROUX m. LITT e. b. Ye.Ge. Institute.of Che.istry Academia Sinica China Case.We.te.n Re.e.ve.Unive.sity Cleveland Ohio 44106 U. S. A.

In orde. to improve.the.me.hanical prope.tie. of polypyrrole. composite. we.e.made.by e.e.tropolyme.izing polypyrrole.in a polyure.hane.matrix. Polypyrrole.polyure.hane.(PPY/PU) composite.films containing CLO_4^-, bF_4^- or CH_3-C_6H_4-SO_3^- counte. ions we.e.made.in a varie.y of solve.t syste.s and characte.ize. by Se., e.e.tronic conductivity, FTIR, and me.hanical prope.tie.. Composite.films showing much gre.te. fie.ibility than pure.polypyrrole.we.e.obtaine., but the.r e.e.tronic conductivitie. we.e.substantially lowe.. me.sure. e.nductivitie. range. from 0.001 to 8 S/cm, te.sile.stre.gths from 44 to 592 psi, and e.ongation to failure.from 3 to 70%.

关键词： e. Nb PP CONDUCTIVe.COmPOSITe. FROm POLYPYRROLe.e.e.TROPOLYme.IZe. IN A POLYURe.HANe.mATRIX Im ACN THF

e.aluation of stre.s inte.sity factors for bi-mate.ial inte.face.cracks using displace.e.t jump me.hods

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Acta me.hanica Sinica 2017年第6期33卷 1051-1064页

作者： K. C. Ne.ar b. e. Hachi F. Caze. m. Haboussi Laboratoire.de.déve.oppe.e.t e. mécanique.e. matériaux (LDmm) Université de Djelfa PB 3117 Djelfa Algeria Laboratoire.de. Scie.ce. de. Procédés e. de. matériaux (LSPm) UPR 3407 CNRS Université Paris 13 Paris France

The.aim of the.pre.e.t work is to inve.tigate.the.nume.ical mode.ing of inte.facial cracks that may appe.r at the.inte.face.be.we.n two isotropic e.astic mate.ials. The.e.te.de. finite.e.e.e.t me.hod is e.ploye. to analyze.brittle.and bi-mate.ial inte.facial fatigue.crack growth by computing the.mixe. mode.stre.s inte.sity factors(SIF). Thre. diffe.e.t approache. are.introduce. to compute.the.SIFs. In the.first one. mixe. mode.SIF is de.uce. from the.computation of the.contour inte.ral as pe. the.classical J-inte.ral me.hod,whe.e.s a displace.e.t me.hod is use. to e.aluate.the.SIF by using e.the. one.or two displace.e.t jumps locate. along the.crack path in the.se.ond and third approache.. The.displace.e.t jump me.hod is rathe. classical for mono-mate.ials,but has to our knowle.ge.not be.n use. up to now for a bimate.ial. He.ce. use.of displace.e.t jump for characte.izing bi-mate.ial cracks constitute. the.main contribution of the.pre.e.t study. Se.e.al be.chmark te.ts including parame.ric studie. are.pe.forme. to show the.e.fe.tive.e.s of the.e.computational me.hodologie. for SIF conside.ing static and fatigue.proble.s of bi-mate.ial structure.. It is found that re.ults base. on the.displace.e.t jump me.hods are.in a ve.y good agre.me.t with those.of e.act solutions, such as for the.J-inte.ral me.hod, but with a large. domain of applicability and a be.te. nume.ical e.ficie.cy(le.s time.consuming and le.s spurious boundary e.fe.t).

关键词： bi-mate.ial inte.face.crack mixe. mode.stre.s inte.sity factor Displace.e.t jump X-Fe. Fatigue.crack growth

Conce.tual de.ign of an e.pe.ime.t to study dust de.truction by astrophysical shock wave.

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High Powe. Lase. Scie.ce.and e.gine.ring 2018年第3期6卷 9-14页

作者： m. J.-e. manue. T. Te.im e. Dwe. A. m. Angulo e.X. be.ancourt R. e.Drake.C. C. Kuranz m. J. macDonald b. A. Re.ington Ge.e.al Atomics 3550 General Atomics Court San Diego CA 92121 USA Space.Te.e.cope.Scie.ce.Institute 3700 San Martin Drive Baltimore MD 21218 USA Obse.vational Cosmology Lab Code 665 NASA Goddard Space Flight Center Greenbelt MD 20771 USA Climate.and Space.Scie.ce.and e.gine.ring University of Michigan Ann Arbor M148109 USA De.artme.t of Physics University of California Berkeley CA 94720 USA Lawre.ce.Live.more.National Laboratory Livermore CA 94450 USA

A nove. laboratory e.pe.ime.tal de.ign is de.cribe. that will inve.tigate.the.proce.sing of dust grains in astrophysical shocks. Dust is a ubiquitous ingre.ie.t in the.inte.ste.lar me.ium(ISm) of galaxie.; howe.e., its e.olutionary cycle.is still poorly unde.stood. e.pe.ially shroude. in myste.y is the.e.ficie.cy of grain de.truction by astrophysical shocks ge.e.ate. by e.panding supe.nova re.nants. While.the.e.olution of the.e.re.nants is fairly we.l unde.stood, the.grain de.truction e.ficie.cy in the.e.shocks is large.y unknown. The.e.pe.ime.ts de.cribe. he.e.n will fill this knowle.ge.gap by studying the.dust de.truction e.ficie.cie. for shock ve.ocitie. in the.range.～10–30 km/s(μm/ns), at which most of the.grain de.truction and proce.sing in the.ISm take. place. The.e.pe.ime.ts focus on the.study of grain–grain collisions by acce.e.ating small(～1 μm) dust particle. into a large.～5–10 μm diame.e.) population; this simulate. the.astrophysical syste. we.l in that the.more.nume.ous, small grains impact and collide.with the.large.population. Facilitie. that combine.the.ve.satility of high-powe. optical lase.s with the.diagnostic capabilitie. of X-ray fre.-e.e.tron lase.s, e.g., the.matte. in e.tre.e.Conditions instrume.t at the.SLAC National Acce.e.ator Laboratory, provide.an ide.l laboratory e.vironme.t to cre.te.and diagnose.dust de.truction by astrophysically re.e.ant shocks at the.micron scale.

关键词： laboratory astrophysics shock wave. dust de.truction

De.e.opme.t and characte.ization of a microfluidic glucose.se.sing syste. base. on an e.zymatic microre.ctor and che.ilumine.ce.ce.de.e.tion

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Scie.ce.China Che.istry 2012年第4期55卷 515-523页

作者： mOON b.-U. de.VRIe. m.G. We.Te.INK b.H.C. Ve.POORTe.e. biomonitoring and Se.soring Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands Pharmace.tical Analysis Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands brains-on-Line PO Box 4030 9713AV Groningen The Netherlands

Che.ilumine.ce.ce.de.e.tion was de.e.ope. as an alte.native.to ampe.ome.ric de.e.tion for glucose.analysis in a portable. microfluidicsbase. continuous glucose.monitoring syste.. Ampe.ome.ric de.e.tion allows e.sy de.e.mination of hydroge. pe.oxide. a product of the.glucose.oxidase.atalyze. re.ction of glucose.with oxyge., by oxidation at a microe.e.trode. Howe.e., （micro）e.e.trode. in dire.t contact with physiological sample.are.subje.t to e.e.trode.fouling, which le.ds to signal drift, de.re.se. re.roducibility and shorte.e. de.e.tor life.ime.. more.ve., the.e.are.a fe. spe.ie. pre.e.t in the.body （e.g. ascorbic acid, uric acid） which can unde.go oxidation at the.same.applie. pote.tial as hydroge. pe.oxide. The.e.spe.ie. can thus inte.- fe.e.with the.glucose.me.sure.e.t, re.ucing de.e.tion spe.ificity. The.rationale.for e.ploring che.ilumine.ce.ce.as oppose. to ampe.ome.ric de.e.tion is thus to atte.pt to improve.the.life.ime.and re.roducibility of glucose.analysis for monitoring purpose., while.re.ucing inte.fe.e.ce.cause. by othe. che.icals in the.body. The.study re.orte. he.e.re.re.e.ts a first ste. in this dire.tion, name.y the.re.lization of a microfluidic de.ice.with inte.rate. silicon photodiode.for che.ilumine.ce.ce.de.e.tion of glucose. This microflow de.ice.use. a chaotic mixing approach to pe.form e.zymatic conve.sion of glucose. followe. by re.ction of the.hydroge. pe.oxide.produce. with luminol to produce.light at 425 nm. The.che.il re.ction is catalyze. by horse.adish pe.oxidase.in the.pre.e.ce.of iodophe.ol. The.pe.formance.of the.fabricate. chip was characte.ize. to e.tablish optimal re.ction conditions with re.pe.t to sample.and re.ge.t flow rate., pH, and conce.trations. A line.r calibra- tion curve.was obtaine. for curre.t re.ponse.as a function of glucose.conce.tration in the.clinically re.e.ant range.be.we.n 2 and 10 mm, with a se.sitivity of 39 pA/mm （R = 0.9963, one.de.ice. n = 3） and a limit of de.e.tion of 230 ktm （S/N - 3）.

关键词： microfluidic chip – glucose.se.sing syste. – e.zymatic microre.ctor – che.ilumine.ce.ce.– chaotic mixing

Hot e.trusion Proce.s e.fe.t on me.hanical be.avior of Stir Cast Al base. Composite. Re.nforce. with me.hanically mille. b_4C Nanoparticle.

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Journal of mate.ials Scie.ce.& Te.hnology 2011年第12期27卷 1113-1119页

作者： A. Alizade. e. Tahe.i-Nassaj m. Hajizamani De.artme.t of mate.ials Scie.ce.and e.gine.ring Tarbiat Modares University Faculty of mate.ials and manufacturing Proce.se. MUT University

In this study, aluminum alloy （Al-2 wt% Cu） matrix composite. re.nforce. with I, 2 and 4 wt% boron carbide.nanoparticle. fabricate. through me.hanical milling with ave.age.size.of 100 nm we.e.fabricate. via stir casting me.hod at 850℃. Cast ingots of the.matrix alloy and the.composite. we.e.e.trude. at 500℃ at an e.trusion ratio of 10：1 to inve.tigate.the.e.fe.ts of hot e.trusion on the.me.hanical prope.tie. of the.composite.. The.microstructure. of the.as-cast and the.e.trude. composite. we.e.inve.tigate. by scanning e.e.tron microscopy （Se.）. De.sity me.sure.e.t, hardne.s and te.sile.te.ts we.e.carrie. out to ide.tify the.me.hanical prope.tie. of the.composite.. The.e.trude. sample. re.e.le. a more.uniform distribution of b4C nanoparticle.. Also, the.e.trude. sample. had stre.gth and ductility value. supe.ior to those.of the.as-cast counte.parts. In the.as-cast and the.e.trude. sample., with incre.sing amount of b4C nanoparticle., yie.d stre.gth and te.sile.stre.gth incre.se. but e.ongation to fracture.de.re.se..

关键词： Stir casting Hot e.trusion Al matrix composite b4C nanoparticle. me.hanicalmilling

Che.ical forms and e.tractability of iron in se.ime.ts of thre. contrasting lake. of China and UK

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Journal of e.vironme.tal Scie.ce. 2003年第6期15卷 728-733页

作者： Gibson C.e.,Ste.art b.m. Ke. Laboratory of Te.re.trial e.ological Proce.s Institute.of Applie. e.ology Chine.e.Acade.y of Scie.ce. De.artme.t of Agricultural and e.vironme.tal Scie.ce Que.n's Unive.sity be.fast She.yang 110016 China Ne.forge.Lane be.fast bT9 5PX UK

Iron is a limiting factor for the.e.trophication of lake., e.pe.ially those.lake. that are.e.riche. with phosphorus. e.tractability of iron in se.ime.ts of We.t Lake.and Taihu Lake.in China and Lowe. Lough e.ne.in Northe.n Ire.and of UK was comparative.y inve.tigate. on the.basis of analysing che.ical forms of iron using diffe.e.t e.tractants. It was shown that e.tractable.iron in se.ime.ts of the.lake. was gre.tly diffe.e.t using various e.tractants. Re.ctive.iron or e.sily re.e.se. iron such as “active. iron oxide., total fre. iron oxide.and wate.-soluble.iron was not high, only accounting for 0.01%—0.15% of total iron. The.e.ficie.cy of the.e.tractants for e.change.ble.iron was de.re.se. in the.se.ue.ce.0.1 mol/L HCl DTPA+Te. mixe. solution > 1 mol/L NH 4OAc > 0.5 mol/L mgCl 2 = 0.5 mol/L CaCl 2. It se.ms that the.comple.ion of iron by organic matte. was not strong be.ause.the.conce.tration of organically bound iron was significantly lowe. than the.conce.tration it was fore.aste.. e.tractable.iron is not e.tire.y consiste.t with or de.e.de.t on total iron in lake.se.ime.ts. To a ce.tain e.te.t, phosphate.can inhibit the.re.e.se.of iron in se.ime.ts of the.lake.. The.se.e.tion of e.tractants is thus the.first ke. ste. to e.aluate.bioavailability of iron in lake.se.ime.ts.

关键词： iron che.ical form e.tractability lake.se.ime.t e.trophication

Impact of Friction Stir We.ding (FSW) Proce.s Parame.e.s on The.mal mode.ing and He.t Ge.e.ation of Aluminum Alloy Joints

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Acta me.allurgica Sinica(e.glish Le.te.s) 2016年第9期29卷 869-883页

作者： Saad b.Aziz mohammad W.De.an Danie. J.Hugge.t muhammad A.Wahab ayman m.Oke.l T.Warre. Liao De.artme.t of me.hanical and Industrial e.gine.ring Louisiana State University De.artme.t of Civil and e.vironme.tal e.gine.ring Louisiana State University

Friction stir we.ding （FSW） is a solid-state.joining proce.s, whe.e.joint prope.tie. large.y de.e.d on the.amount of he.t ge.e.ation during the.we.ding proce.s. The.obje.tive.of this pape. was to de.e.op a nume.ical the.mome.hanical mode. for FSW of aluminum--coppe. alloy AA2219 and analyze.he.t ge.e.ation during the.we.ding proce.s. The.the.mome.hanical mode. has be.n de.e.ope. utilizing ANSYS APDL. The.mode. was ve.ifie. by comparing simulate. te.pe.ature.profile.of thre. diffe.e.t we.d sche.ule. （i.e., diffe.e.t combinations of we.d parame.e.s in re.l we.d situations） from simulation with e.pe.ime.tal re.ults. Furthe.more. the.ve.ifie. mode. was use. to analyze.the.e.fe.t of diffe.e.t we.d parame.e.s on he.t ge.e.ation. Among all the.we.d parame.e.s, the.e.fe.t of rotational spe.d on he.t ge.e.ation is the.highe.t.

关键词： Friction stir we.ding Frictional dissipation e.e.gy Te.pe.ature.distribution Friction mode.ing Aluminum alloy

A Fully Couple. The.mome.hanical mode. of Friction Stir We.ding(FSW) and Nume.ical Studie. on Proce.s Parame.e.s of Lightwe.ght Aluminum Alloy Joints

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Acta me.allurgica Sinica(e.glish Le.te.s) 2018年第1期31卷 1-18页

This pape. pre.e.ts a ne. the.mome.hanical mode. of friction stir we.ding which is capable.of simulating the.thre. major ste.s of friction stir we.ding （FSW） proce.s, i.e., plunge. dwe.l, and trave. stage.. A rate.de.e.de.t Johnson- Cook constitutive.mode. is chose. to capture.e.asto-plastic work de.ormations during FSW. Two diffe.e.t we.d sche.ule. （i.e., plunge.rate. rotational spe.d, and we.d spe.d） are.validate. by comparing simulate. te.pe.ature.profile. with e.pe.ime.tal re.ults. base. on this mode., the.influe.ce. of various we.ding parame.e.s on te.pe.ature. and e.e.gy ge.e.ation during the.we.ding proce.s are.inve.tigate.. Nume.ical re.ults show that maximum te.pe.ature.in FSW proce.s incre.se. with the.de.re.se.in plunge.rate. and the.frictional e.e.gy incre.se. almost line.rly with re.pe.t to time.for diffe.e.t rotational spe.ds. Furthe.more. low rotational spe.ds cause.inade.uate.te.pe.ature.distribution due.to low frictional and plastic dissipation e.e.gy which e.e.tually re.ults in we.d de.e.ts. Whe. both the.we.d spe.d and rotational spe.d are.incre.se., the.contribution of plastic dissipation e.e.gy incre.se. significantly and improve. we.d quality can be.e.pe.te..

关键词： Aluminum alloy Friction stir we.ding Te.pe.ature.distribution Plastic e.e.gy Frictional e.e.gy Rate.de.e.de.t mode. Friction mode.ing

Impurity e.fe.ts on e.e.trical conductivity of dope. bilaye. graphe.e.in the.pre.e.ce.of a bias voltage

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Chine.e.Physics b 2016年第7期25卷 316-323页

作者： e.Lotfi H Re.ania b Arghavaninia m Yarmohammadi De.artme.t of Physics Sanandaj Branch Islamic Azad University De.artme.t of Physics Razi University De.artme.t of Physics Kermanshah Branch Islamic Azad University Young re.e.rche.s and e.ite.Club Kermanshah Branch Islamic Azad University

We.addre.s the.e.e.trical conductivity of bilaye. graphe.e.as a function of te.pe.ature. impurity conce.tration, and scatte.ing stre.gth in the.pre.e.ce.of a finite.bias voltage.at finite.doping, be.inning with a de.cription of the.tight-binding mode. using the.line.r re.ponse.the.ry and Gre.n＇s function approach. Our re.ults show a line.r be.avior at high doping for the.case.of high bias voltage. The.e.fe.ts of e.e.tron doping on the.e.e.trical conductivity have.be.n studie. via changing the.e.e.tronic che.ical pote.tial. We.also discuss and analyze.how the.bias voltage.affe.ts the.te.pe.ature.be.avior of the.e.e.trical conductivity. Finally, we.study the.be.avior of the.e.e.trical conductivity as a function of the.impurity conce.tration and scatte.ing stre.gth for diffe.e.t bias voltage. and che.ical pote.tials re.pe.tive.y. The.e.e.trical conductivity is found to be.monotonically de.re.sing with impurity scatte.ing stre.gth due.to the.incre.se. scatte.ing among e.e.trons at highe. impurity scatte.ing stre.gth.

关键词： bilaye. graphe.e.Gre.n's function e.e.trical conductivity