检索结果-南通市图书馆

j.urn.l of Materials Scien.e & Techn.logy 2022年第2期97卷 264-271页

作者： young-Kyun.Kim Kee-Ahn.Lee Departmen. of Materials Scien.e an. En.in.erin. Inha UniversityIncheon 22212Republic of Korea

Cold spray(CS)which has recen.ly become a promisin. additive man.facturin.(AM)techn.logy,was used to fabricate ultra-stron. pure *** addition.the effects of carrier gas species on.the microstructural characteristics,mechan.cal properties an. deformation.mechan.sms were systemically *** CSAM copper man.factured with n.(2) carrier gas reveals a heterogen.ous bimodal microstructure con.istin. of ultra-fin. grain. at the particle in.erface an. relatively coarse grain. in.in.er *** He carrier gas,a homogen.ous grain.structure con.istin. of ultra-fin. grain. in.most areas was *** tests showed that n.(2) an. He carrier gasses en.bled ultra-high yield stren.ths of 340 an.415 MPa,*** values are comparable to severely plastic deformed copper,which has extremely low ductility an. shape *** the other han.,both samples showed a strain.soften.n. phen.men.n.that does n.t common.y occur at room *** deformation.microstructures revealed that dyn.mic recovery(DRV)an. dyn.mic recrystallization.DRX)phen.men. were gen.rated despite bein. deformed at room *** on.the above fin.in.s,the overall deformation.mechan.sms accordin. to the carrier gas species in.the CSAM copper man.facturin. process were ***,the work harden.n. an. soften.n. behaviors of CSAM Cu are predicted by usin. a con.titutive equation.

关键词： Cold spray additive man.facturin. Carrier gas Pure Cu Mechan.cal properties Deformation.behavior

Precambrian.supercon.in.n.s,glaciation.,atmospheric oxygen.tion.metazoan.evolution.an. an.impact that may have chan.ed the secon. half of Earth history

在线全文

学校读者我要写书评

暂无评论

Geoscien.e Fron.iers 2013年第3期4卷 247-261页

作者： Gran. M.young Departmen. of Earth Scien.es Western University1151 Richmond Street NLondonOntarioCanada N6A 5B7

In.more than.4 Ga of geological evolution. the Earth has twice gon. through extreme climatic perturba- tion., when.exten.ive glaciation. occurred, together with altern.tin. warm periods which were accom- pan.ed by atmospheric oxygen.tion. The younger of these two episodes of climatic oscillation.preceded the Cambrian.＂explosion. of metazoan.life forms, but similar extreme climatic con.ition. existed between.about 2.4 an. 2.2 Ga. Over lon. time periods, chan.in. solar lumin.sity an. man.le temperatures have played importan. roles in.regulatin. Earth＇s climate but both periods of climatic upheaval are associated with supercon.in.n.s. En.an.ed weatherin. on.the orogen.cally an. thermally buoyed supercon.in.n.s would have stripped CO2 from the atmosphere, in.tiatin. a coolin. tren. that resulted in.con.in.n.al glaciation. Ice cover preven.ed weatherin. so that CO2 built up on.e more, causin. collapse of the ice sheets an. usherin. in.a warm climatic episode. This n.gative feedback loop provides a plausible explan.tion.for multiple glaciation. of the Early an. Late Proterozoic, an. their in.imate association.with sedimen.ary rocks formed in.warm climates. Between.each glacial cycle n.trien.s were flushed in.o world ocean., stimulatin. photosyn.hetic activity an. causin. oxygen.tion.of the atmosphere. Accommodation.for man. an.ien. glacial deposits was provided by riftin. but escape from the climatic cycle was predicated on.break- up of the supercon.in.n., when.flooded con.in.n.al margin. had a moderatin. in.luen.e on.weatherin.. The geochemistry of n.oproterozoic cap carbon.tes carries a stron. hydrothermal sign.l, suggestin. that they precipitated from deep sea waters, overturn.d an. spilled on.o con.in.n.al shelves at the termin.tion.of glaciation.. Paleoproterozoic （Huron.an. carbon.tes of the Espan.la Formation.were probably formed as a result of pon.in. an. evaporation.in.a hydrothermally in.luen.ed, restricted rift settin.. Why did metazoan.evolution.n.t take off a

关键词： Proterozoic supercon.in.n.s Glaciation. Impacts Oxygen.tion.Metazoa

Effect of Particulate Rein.orcemen. on.the Mechan.cal Properties of Al2024-WC MMCs

在线全文

学校读者我要写书评

暂无评论

j.urn.l of Min.rals an. Materials Characterization.an. En.in.erin. 2015年第6期3卷 469-476页

作者： K. Pun.th Gowda j. n. Prakash Shivashan.are Gowda B. Satish Babu Departmen. of Mechan.cal En.in.erin. East West Institute of Technology Bengaluru India St j.hn. College of En.in.erin. an. Techn.logy Yemmiganur India Swarn.n.hra In.titute of En.in.erin. & Techn.logy Narasapur India

The presen. work reveals the study of mechan.cal properties of Al2024-Tun.sten.carbide MMCs con.ain.n. tun.sten.carbide (WC) particulates. The rein.orcin. particulates in.the Al2024 alloy were varied from 0% to 5% by weight. The vortex method of cast production.was employed to fabricate the MMCs, in.which the rein.orcemen. was poured in.o the vortex created by stirrin. the molten.metal by mean. of a mechan.cal agitator. The composite so produced was subj.cted to a series of mechan.cal tests. The results of this study revealed that as the tun.sten.carbide particle con.en. was in.reased, there were sign.fican. in.reases in.the ultimate ten.ile stren.th, hardn.ss an. young’s modulus, compressive stren.th, accompan.ed by a reduction.in.its ductility. An.attempt is made in.the paper to provide explan.tion. for these phen.men..

关键词： Alumin.um 2024 Alloys Tun.sten Carbide Stir Castin. Mechan.cal Properties

Ex vivo evaluation.of IVUS-VH imagin. an. the role of plaque structure on.peripheral artery disease

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Medicin. in.n.vel Techn.logy an. Devices 2020年第4期8卷 22-30页

作者： christopher n.ble Ken. Carlson.Erica n.uman. Bradley Lewis Dan.Dragomir-Daescu Amir Lerman.Ahmet Erdemir Melissa young Departmen. of Cardiovascular Medicin. Mayo ClinicRochesterMNUSA Departmen. of Physiology an. Biomedical En.in.erin. Mayo ClinicRochesterMNUSA Departmen. of Biomedical En.in.erin. an. Computation.l Biomodelin.(CoBi)Core Lerner Research InstituteCleveland ClinicClevelandOHUSA Division.of Biomedical Statistics an. In.ormatics Mayo ClinicRochesterMNUSA

Peripheral artery disease(PAD)results from the buildup of atherosclerotic plaque in.the arterial wall,can.progress to severe ischemia an. lead to tissue n.crosis an. limb *** evaluated a mean. of assessin. PAD mechan.cs ex vivo usin. ten.human.peripheral arteries with ***-in.lation.testin. was performed at six physiological pressure in.ervals ran.in. from 10 to 200 *** vessels were imaged with IVUS-VH to determin. plaque composition.an. chan.e in.vessel structure with *** an.lysis was performed to determin. which plaque structures an. distribution. of these structures had the greatest in.luen.e on.wall *** foun. that fibrous plaque,n.crotic core,an. calcification.had a statistically sign.fican. effect on.all variables(pn.e of large con.en.ration. of fibrous plaque was lin.ed to reduced vessel complian.e an. ellipticity,which could lead to sten. fractures an. *** the plaque distribution.we foun. that clustered n.crotic core in.reased overall complian.e while clustered calcification.decreased overall *** effect of plaque distribution.on.vessel wall deformation.must be con.idered equally importan. to plaque con.en.ration.

关键词： In.rasvascular ultrasoun. Virtual histology Peripheral artery disease Pressure-in.lation.testin. Atherosclerosis

Kin.tic an. Microstructural An.lyses of Chromia Formin. Alloys durin. Cyclic Oxidation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国腐蚀与防护学报 2009年第4期29卷 315-315页

作者： n.K.OTHMAn.D.j.young School of Materials Scien.e & En.in.erin. University of New South WalesSydney 2052 Australia

Three Fe-Cr model alloys(Cr:9,17,an. 25 wt%) were subj.cted to cyclic oxidation.in.Ar-10%H_2-5%H_2O(p_(o_2)=3.6×10^(-22) atm),Ar-20%O_2 an. Ar-20%O_2-5%H_2O atmospheres at 700℃.In.gen.ral,in.reasin. alloy chromium levels reduced the oxidation.*** high p_(o_2),in.the absen.e of water vapour,the 9%Cr alloy exhibited breakaway oxidation.at the begin.in. of the ***, for chromium levels≥17%,n. breakaway oxidation.occurred,an. the weight gain.was very *** water vapour to Ar-20%O_2 accelerated the oxidation.of alloys con.ain.n. 17%Cr or ***,this acceleratin. effect was n.t eviden. for high chromium *** low p_(o_2),breakaway oxidation.of alloys with chromium con.en.ration.17%occurred after 300 cycles *** chromium con.en. alloys did n.t un.ergo sign.fican. *** an.lysis showed that for low chromium con.en. alloys(Cr≤17%), spin.l an. wustite were formed in.the low p_(o_2) gas,while in.the high p_(o_2) gas,hematite,magn.tite an. spin.l were *** the case of high chromium alloys,on.y Cr_2O_3 was *** examin.tion.showed that the spin.l was presen. in.the form of in.ern.l precipitates.A den.e chromia layer was observed at alloy chromium levels above 25%.The reason. for the differen.e in.oxidation.behaviour at differen. oxygen.poten.ials,an. the effect of water vapour are discussed in.con.ection.with the microstructure of the oxides.

关键词：镁合金氧化腐蚀防护

Multi-mode diagn.sis of a gas turbin. en.in. usin. an.adaptive n.uro-fuzzy system

在线全文

学校读者我要写书评

暂无评论

Chin.se j.urn.l of Aeron.utics 2018年第1期31卷 1-9页

作者： Houman.HAn.CHI j.e LIU christopher MECHEFSKE n.tion.l Research Base of In.elligen. Man.facturin. Service Chongqing Technology and Business University Chongqing 400067 China Departmen. of Mechan.cal an. Materials En.in.erin. Queen's University Kingston ON K7L 3N6 Canada Departmen. of Mechan.cal an. Aerospace En.in.erin. Carleton University Ottawa ON K1S 5B6 Canada

Gas Turbin. En.in.s （GTEs） are vastly used for gen.ration.of mechan.cal power in.a wide ran.e of application. from airplan. propulsion.systems to station.ry power plan.s. The gaspath compon.n.s of a GTE are exposed to harsh operatin. an. ambien. con.ition., leadin. to several degradation.mechan.sms. Because GTE compon.n.s are mostly in.ccessible for direct measure- men.s an. their degradation.levels must be in.erred from the measuremen.s of accessible parameters, it is a challen.e to acquire reliable in.ormation.on.the degradation.con.ition. of the parts in.differen. fault modes. In.this work, a data-driven.fault detection.an. degradation.estima- tion.scheme is developed for GTE diagn.stics based on.an.Adaptive n.uro-Fuzzy In.eren.e System （An.IS）. To verify the performan.e an. accuracy of the developed diagn.stic framework on.GTE data, an.en.emble of measurable gas path parameters has been.gen.rated by a high-fidelity GTE model un.er （a） diverse ambien. con.ition. an. con.rol settin.s, （b） every possible combin.tion.of degradation.symptoms, an. （c） a broad ran.e of sign.l to n.ise ratios. The results prove the competen.y of the developed framework in.fault diagn.stics an. reveal the sen.itivity of diagn.stic results to measuremen. n.ise for differen. degradation.symptoms.

关键词： Fault detection Multi-mode diagn.sis Measuremen. n.ise Real-time diagn.sis

ABCD^(2) risk score does n.t predict the presen.e of cerebral microemboli in.patien.s with hyper-acute symptomatic critical carotid artery sten.sis

在线全文

学校读者我要写书评

暂无评论

Stroke & Vascular n.urology 2017年第2期2卷 41-46页

作者： Mahmud Saedon.Charles E Hutchin.on.christopher H E Imray Don.ld R j.Sin.er Warwick Medical School University of WarwickCoventryUK Un.versity Hospitals Coven.ry Warwickshire n.S Trust CoventryUK Fellowship of Postgraduate Medicin. LondonUK Yale School of Medicin. New HavenConnecticutUSA

In.roduction.ABCD^(2) risk score an. cerebral microemboli detected by tran.cran.al Doppler(TCD)have been.separately shown.to the predict risk of recurren. acute *** studied whether ABCD2 risk score predicts cerebral microemboli in.patien.s with hyper-acute symptomatic carotid artery *** an. methods:We studied 206 patien.s presen.in. within.2 weeks of tran.ien. ischaemic attack or min.r stroke an. foun. to have critical carotid artery sten.sis(≥50% ).86 patien.s(age 70±1(SEM:years),58 men.83 Caucasian.had eviden.e of microemboli;72(84% )of these un.erwen. carotid en.arterectomy(CEA).120 patien.s(age 72±1 years,91 men.113 Caucasian.did n.t have microemboli detected;102(85% )of these un.erwen. *** were an.lysed usin. X2 an. Man.–Whitn.y U tests an. receiver operatin. characteristic(ROC)***:140/206(68% :95% CI 61.63 to 74.37)patien.s with hyper-acute symptomatic critical carotid sten.sis had an.ABCD2 risk score≥*** was n. sign.fican. differen.e in.the n.CE red flag criterion.for early assessmen.(ABCD^(2) risk score≥4)for patien.s with cerebral microemboli versus those without microemboli(59/86 vs 81/120 patien.s:OR 1.05 ABCD2 risk score≥4(95% CI 0.58 to 1.90,p=0.867)).The ABCD2 risk score wasn.27 of 86(31% :95% CI 21 to 41)embolisin. patien.s an. in.39 of 120(31% :95% CI 23 to 39)without cerebral *** adj.stin. for pre-n.urological even. an.iplatelet treatmen.(APT),area un.er the curve(AUC)of ROC for ABCD2 risk score showed n. prediction.of cerebral microemboli(n. pre-even. APT,n.57:AUC 0.45(95% CI 0.29 to 0.60,p=0.531);preeven. APT,n.147:AUC 0.51(95% CI 0.42 to 0.60,p=0.804)).Con.lusion.:The ABCD2 score did n.t predict the presen.e of cerebral microemboli or carotid disease in.over on.-quarter of patien.s with symptomatic critical carotid artery *** the basis of n.CE guidelin.s(refer early if ABCD2≥4),assessmen. of high stroke risk based on.ABCD2 scorin. may lead to in.ppropriate delay in.urgen. treat

关键词： patien.s cerebral emboli

Germin.tion.respon.e of desert an.uals to shrub facilitation.is species specific but n.t ecotypic

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urn.l of Plan. Ecology 2017年第2期10卷 364-374页

作者： Aman.a R.Liczn.r Diego A.Sotomayor Alessan.ro Filazzola christopher j.Lortie Departmen. of Biology York University4700 Keele St.TorontoOntario M3J1P3Canada Departmen. of Geography York University4700 Keele St.TorontoOntario M3J1P3Canada

Aims Positive plan. in.eraction. can.promote higher species den.ity of ben.ficiary species in.***,there is limited eviden.e examin.n. the trait sets of seeds from ben.ficiary *** this study,we examin.d the hypothesis that shrubs(ben.factors)in.lu-en.e the germin.tion.of desert an.uals(ben.ficiaries)an. promote ecotypic differen.iation.by gen.ratin. distin.t microhabitats through abiotic stress *** followin. prediction. were tested usin. growth chambers an. field-collected seeds:(i)seed mass an. viability will be greater an. less variable for seeds collected from within.shrub un.erstory relative to seeds from open.microhabitats,(ii)germin.tion.of seeds from shrub an. open.microhabitats will be greatest un.er simulated home(source)con.ition.,(iii)seeds from the shrub microhabitat will adaptively accelerate their germin.tion.rate when.germin.ted in.simulated home(source)microhabitats relative to their simulated away(reciprocal)*** Seeds an. their associated matern.l plan.s were collected from four an.ual species foun. within.a shrub un.erstory(Larrea triden.tata)an. open.microhabitats in.the Moj.ve Desert of Californ.a(35.30ºn.117.26ºW,793 m.a.s.l.),an. then.reciprocally germi-n.ted in.growth chambers simulatin. both microclimatic *** germin.tion.an. germin.tion.rate was measured every 4-5 days for 42 *** Fin.in.s There was n. sign.fican. differen.e in.the mean.or coefficien. of variation.for seed mass an. viability between.the shrub an. open.*** source of the seeds did n.t sign.fican.ly impact the cumulative germin.tion.an. there was n. accelerated rate of germin.tion.within.poten.ial species ecotypes thereby suggestin. n. ecotypic *** germin.tion.was sign.fi-can.ly higher within.the shrub-simulated microhabitat for three out of the four species *** germin.tion.an. germin.-tion.rate were sign.fican.ly differen. between.***,shrubs

关键词： ecotypes facilitation germin.tion seeds viability

Applyin. reticular syn.hesis to the design.of Cu-based MOFs with mechan.cally in.erlocked lin.ers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

n.n. Research 2021年第2期14卷 417-422页

作者： Alexan.er j.Stirk Ben.amin.H.Wilson.christopher A.O’Keefe Hazem Amame Kelon. Zhu Robert W.Schurko Stephen.j.Loeb Departmen. of Chemistry an. Biochemistry University of WindsorWindsorOntarioN9B 3B4Canada Departmen. of Chemistry The University of JordanAmman11942Jordan School of Chemistry Sun Yat-Sen UniversityGuangzhou 510275China Departmen. of Chemistry an. Biochemistry Florida State UniversityTallahasseeFlorida 32306-4390USA

The con.ept of“robust dyn.mics”describes the in.orporation.of mechan.cally in.erlocked molecules(MIMs)in.o metal-organ.c framework(MOF)materials such that large amplitude motion.(e.g.,rotation.or tran.lation.of a macrocycle)can.occur in.ide the free volume pore of the *** aid in.the preparation.of such materials,reticular syn.hesis was used herein.to design.rigid molecular buildin. blocks with predetermin.d ordered structures startin. from the well-kn.wn.MOF *** lin.ers were syn.hesized that have a T-shape,based on.a triphen.len. tetra-carboxylate strut,an. their in.orporation.in.o Cu(II)-based MOFs was *** sin.le-crystal structures of three n.w MOFs,UWCM-12(fof),β-UWCM-13(loz),UWCM-14(lil),with n.ked T-shaped lin.ers were determin.d;β-UWCM-13 is the first reported example of the loz topology.A fourth MOF,UWDM-14(lil)is an.logous to UWCM-14(lil)but con.ain. a[2]rotaxan. ***-temperature,^(2)H solid-state n.R was used to probe the dyn.mics of a 24-membered macrocycle threaded on.o the MOF skeleton.

关键词： reticular chemistry metal-organ.c frameworks mechan.cally in.erlocked molecules rotaxan.

Double-sided friction.stir weldin. of n.tron.c-40 stain.ess steel for application.in.tokamak devices

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urn.l of Materials Scien.e & Techn.logy 2023年第28期159卷 170-183页

作者： Supreeth Gaddam Ravi San.ar Haridas Deepthi Tamman. Charlie San.bria christopher j.Lammi Dian. Berman.Raj.v S.Mishra Cen.er for Friction.Stir Processin. Department of Materials Science and EngineeringUniversity of North TexasDentonTX76207USA Advan.ed Materials an. Man.facturin. Processes In.titute University of North TexasDentonTX76207USA Departmen. of Mechan.cal En.in.erin. University of North TexasDentonTX76207USA Common.ealth Fusion.Systems CambridgeMAUSA

n.trogen.con.ain.n. austen.tic stain.ess steels(n.ASS)are widely utilized to fabricate various structural compon.n.s in.tokamak type fusion.reactors owin. to their suitable mechan.cal an. fun.tion.l *** compon.n.s are exposed to a ran.e of temperatures(4-500 K)an. in.eract closely with the magn.tic fields that are used to con.rol an. con.ain.the plasma within.the tokamak ***-40(n.0)or XM-11 stain.ess steel is on. such n.ASS used for fabricatin. structural compon.n.s in.the mag-n.tic an. vacuum vessel systems in.tokamak *** of most of the larger compon.n.s in.the magn.tic an. vacuum vessel systems typically in.olves some type of fusion.based weldin. *** study presen.s a double-sided friction.stir weldin.(FSW)approach as an.altern.tive to fusion.weldin. processes to j.in.12 mm thick n.0 plates to obtain.j.in.s with a low fraction.ofδferrite(a detrimen.tal ferromagn.tic phase),high j.in. efficien.y,n. sen.itization.an. loss of hardn.ss in.the heat affected zon.,an. min.mal n.trogen.desorption.from the weld *** double-sided FSW approach yielded superior weldmen.s when.compared to similar j.in.s accomplished by fusion.weldin. for application.in.tokamak devices.

关键词： Friction.stir weldin. n.tron.c-40 stain.ess steel XM-11 stain.ess steel Magn.tic an. vacuum vessel systems Tokamak devices