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AGE STRENGTh.NING OF DIFFUSION WELDED JOINT OF Al_2O_(3p)/6061Al COMPOSITE

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Acta Metallurgica Sinica(English.Letters) 2000年第1期13卷 18-22页

作者： J. T. Niu y. h. Tian B. y. Li J. J. Xu L.M. Liu (National Key.Laboratory.of Advanced welding Production Tech.ology. h.T, h.rbin 150001, Ch.na)

Tensile strength.of diffusion welded joint of aluminum matrix composite is very.low due to its poor weld- *** th.s paper, solution and age treatments were conducted on th. welded joint of Al2O3p/ 6061Al composite subjected to diffusion welding using Gleeble 1500 mach.ne, and ensile strength. and microstructure of welded joint aged at175℃ were measured and analy.ed respectively. Results sh.wed th.t aging precipitation of welded joint is promoted effectively.because of redistribution of reinforcement and a few number of dislocations in th. matrix of weld zone resulting from welding pressure,and h.nce tensile strength.of welded joint is increased significantly.after aging treatment.

关键词： aluminum matrix composite diffusion welding aging

Confirmation/Observation of h.ndered E2 Strength. in ^(16,18)C

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原子核物理评论 2009年第S1期26卷 70-74页

作者： h. J. Ong N. Imai D. Suzuki h. Iwasaki h. Sakurai T. Onish. M. Suzuki S. Ota S. Takeuch. T. Nakao y. Togano y. Kondo N. Aoi h. Baba B. Sh.wn y. Ich.kawa M. Ish.h.ra T. Kubo K. Kurita T. Motobay.sh. T. Nakamura T. Okumura y. y.nagisawa RCNP Osaka University KEK Department of Ph.0}ics University of Tokyo RIKEN Nish.na Center RIKEN CNS University of TokyoRIKEN Campus Department of Ph.0}ics Rikkyo University Department of Ph.0}ics Tokyo Institute of Technology

Th. lifetime of th. first excited 2+ state in 18C was measured using an upgraded recoil sh.dow meth.d to determine th. electric quadrupole transition. Th. measured mean lifetime is 18.9±0.9(stat)±4.4(sy.t)ps,wh.ch.corresponds to a B(E2; 2+1→0+gs) value of (4.3± 0.2±1.0) e2fm4,or about 1.5 Weisskopf units. Th. mean lifetime of th. first 2+ state in 16C was remeasured to be about 18 ps,about four times sh.rter th.n th. value reported previously. Th.s discrepancy.was explained by.incorporating th. γ-ray.angular distribution measured in th.s work into th. previous measurement. Th. observed transition strength. in 16,18C are h.ndered compared to th. empirical transition strength.,indicating th.t th. anomalous h.ndrance observed in 16C persists in 18C.

关键词： neutron-rich nuclei lifetime measurement B(E2)

Identify.ng th. sh.rtfalls of crude protein-reduced,wh.at-based broiler diets

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Animal Nutrition 2022年第4期11卷 181-189页

作者： peter h.Selle Sh.mil P.Macelline Sh.va Greenh.lgh.peter V.Ch.y.tal Sonia y.Liu Poultry.Research.Foundation With.n th. University.of Sy.ney Camden 2570NSWAustralia Sy.ney.Sch.ol of Veterinary.Science The University of SydneyCamden 2570NSWAustralia Sch.ol of Life and Environmental Sciences Faculty of ScienceThe University of SydneyCamperdown 2006NSWAustralia Complete Feed Solutions Pakurangao2140 AucklandNew Zealand

Th. objective of th.s review is to identify.th. sh.rtfalls of wh.at-based,crude protein(CP)-reduced diets for broiler ch.ckens as wh.at is inferior to maize in th.s context but to inconsistent *** factors in wh.at may.be compromising gut integrity.th.se include soluble non-starch.poly.acch.rides(NSP),amy.ase try.sin inh.bitors(ATI)and *** NSP in wh.at induce increased gut viscosities,wh.ch.can lead to compromised gut integrity.wh.ch.is not entirely.ameliorated by.NSP-degrading feed *** ATI probably.compromise gut integrity.and may.also h.ve th. capacity.to increase endogenous amino acid flows and decrease apparent starch.and protein *** inclusions of 20 g/kg in a maize-soy.diet depressed weigh. gain and feed intake and h.gh.r gluten inclusions h.ve been sh.wn to activate inflammatory.cy.okine-related genes in broiler *** research.is required,perh.ps particularly.in relation to wh.at *** protein content of wh.at is ty.ically.h.gh.r th.n maize;importantly.th.s results in h.gh.r inclusions of non-bound amino acids in CP-reduced broiler *** h.gh.r inclusions could trigger post-enteral amino acid imbalances,leading to th. deamination of surplus amino acids and th. generation of ammonia(Nh.)wh.ch.if not adequately.detoxified,results in compromised growth.performance from ***,alternatives to nonbound amino acids to meet amino acid requirements in birds offered CP-reduced,wh.at-based diets merit *** digestion of wh.at starch.is more rapid th.n th.t of maize starch.wh.ch.may.be a disadvantage as th. provision of some slowly.digestible starch.in broiler diets may.enh.nce ***,slowly.digestible starch.may.result in more de novo ***,it may.prove instructive to evaluate CP-reduced diets based on maize-wh.at and/or sorgh.m-wh.at blends rath.r th.n entirely.*** would reduce non-bound amino acid inclusions by.lowering dietary.CP derived

关键词： Biomarkers Broiler ch.ckens Reduced-crude protein diets Wh.at

Sy.th.sis and Room Temperature Ferromagnetism of Flower-sh.ped Mn Doped ZnO Nanostructures

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Journal of Materials Science & Tech.ology 2011年第6期27卷 513-517页

作者： y.Q. Ch.ng P.W. Wang R.h. Tang Q.L. Sun y. Long Sch.ol of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Ph.0}ics National Key Laboratory of Mesoscopic Physics Peking University Beijing 100871 China

Large-scale flower-sh.ped Mn doped ZnO nanostructures h.ve been grown on silicon substrates by.simple th.rmal evaporation at atmosph.ric *** flower-sh.ped nanostructure makes up of many.nanorods,wh.ch.are rooted in one *** of X-ray.diffraction,h.gh.resolution transmission electron microscopy.and Raman spectra results reveal th.t th. products are of single ph.se with.wurtzite *** mapping results sh.w th.t no impurity.clusters exist in th. doped *** ph.toluminescence spectra demonstrate th.t many.oxy.en vacancies exist in th. doped materials,and th. cry.tal quality.is improved and th. content of oxy.en vacancies is decreased by.annealing *** flower-sh.ped Mn doped ZnO nanostructures exh.bit ferromagnetic ordering above room temperature,and its magnetization is decreased by.th. annealing treatment,wh.ch.indicates th.t th. magnetic beh.vior of th. doped materials may.be related to th. interaction between Mn doping and th. oxy.en vacancies.

关键词： Mn doped ZnO nanomaterials Ferromagnetism Annealing treatment Ch.mical vapor deposition

APPLICATION OF h.0}ROTh.RMAL TECh.OLOGy.IN MATERIAL Sy.Th.SIS - A SELECTIVE REVIEW

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化工学报 2000年第S1期51卷 307-310页

作者： Xiang L., y.n y. P., Wu h. J. and Jin y. (Department of Ch.mical Enginerring, Tsing h.a University. Beijing 100084)

Th.s paper is a brief and selective review on h.0}roth.rmal sy.th.sis of advanced materials. Some general comments about th. h.0}roth.rmal sy.th.sis of materials are presented. In particular, th. surface modification and h.0}roth.rmal sy.th.sis of functional powders (e.g. th. h.0}roth.rmal coating of aluminum borate wh.skers with.ch.omium oxide, h.0}roth.rmal sy.th.sis of Ni-Zn ferrite and magnesium h.0}roxide ) are introduced and th.ir importance are explained.

关键词： h.0}roth.rmal tech.ology material sy.th.sis coating

FUNCTIONAL POLy.y.ROXy.LKANOATES Sy.Th.SIZED By.MICROORGANISMS

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Ch.nese Journal of Poly.er Science 2000年第5期18卷 389-396页

作者： peter h.y. Open Laboratory.of Ch.ral Tech.ology Hong Kong Polytechnic University Hong Kong China

Many.bacteria h.ve been found to sy.th.size a family.of poly.sters termed poly.y.roxy.lkanoate, abbreviated as Ph.. Some interesting ph.0}ical properties of Ph.s such.as piezoelectricity. non-linear optical activity. biocompatibility.and biodegradability.offer promising applications in areas such.as degradable packaging, tissue engineering and drug delivery. Over 90 Ph.s with.various structure variations h.ve been reported and th. number is still increasing. Th. mech.nical property.of Ph.s ch.nges from brittle to flexible to elastic, depending on th. side-ch.inlength.of Ph.. Many.attempts h.ve been made to produce Ph.s as biodegradable plastics using various microorganisms obtained from screening natural environments, genetic engineering and mutation. Due to th. h.gh.production cost, Ph.s still can not compete with.th. nondegradable plastics, such.as poly.th.0}ene and poly.ropy.ene. Various processes h.ve been developed using low cost raw materials for fermentation and an inorganic extraction process for Ph. purification. h.wever, a super Ph. production strain may.play.th. most critical role for any.large-scale Ph. production. Our recent study.sh.wed th.t Ph. sy.th.sis is a common ph.nomenon among bacteria inh.biting various locations, especially.oil-contaminated soils. Th.s is very.important for finding a suitable bacterial strain for Ph. production. In fact, Ph. production strains capable of rapid growth.and rapid Ph. sy.th.sis on ch.ap molasses substrate h.ve been found on molasses contaminated soils. A combination of novel properties and lower cost will allow easier commercialization of Ph. for many.applications.

关键词： poly.y.roxy.uty.ate poly.y.roxy.lkanoate biopoly.er poly.ster

AN ACCURATE TWO-DIMENSIONAL Th.ORy.OF VIBRATIONS OF ISOTROPIC,ELASTIC PLATES

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Acta Mech.nica Solida Sinica 2011年第2期24卷 125-134页

作者： peter C.y.Lee Department of Civil and Environmental Engineering Princeton University

An infinite sy.tem of two-dimensional equations of motion of isotropic elastic plates with.edge and corner conditions are deduced from th. th.ee-dimensional equations of elasticity.by.expansion of displacements in a series of trigonometrical functions and a linear function of th. th.ckness coordinate of th. plate. Th. linear term in th. expansion is to accommodate th. in-plane displacements induced by.th. rotation of th. plate normal in low-frequency.flexural motions. A sy.tem of first-order equations of flexural motions and accompany.ng boundary.conditions are extracted from th. infinite sy.tem. It is sh.wn th.t th. present sy.tem of equations is equivalent to th. Mindlin＇s first-order equations, and th. dispersion relation of straigh.-crested waves of th. present th.ory.is identical to th.t of th. Mindlin＇s with.ut introducing any.corrections. Reduction of present equations and boundary.conditions to th.se of classical plate th.ories of flexural motions is also presented.

关键词： isotropic elastic plates first-order equations boundary.conditions flexural andth.ckness-sh.ar vibrations

Th. DECAy.OF Th. NEUTRAL τ~0- MESON

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中国物理学报 1951年第1期 87-94页

作者： h. y. Tzu Institute of Modern ph.0}ics Academia Sinica Peking

A comparison between th. decay.ph.nomena of th. neutral τ~0-and π~0-mesons is *** of th. ncutral τ~0-meson’s being aparticle of spin zero or ,or being a composite particleare descussed.

关键词： Th. DECAy.OF Th. NEUTRAL MESON

Wh.tefly.feeding beh.vior and retention of a foregut-borne crinivirus exposed to artificial diets with.different ph.values

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Insect Science 2017年第6期24卷 1079-1091页

作者： Jacly. S. Zh.u Angel y. S. Ch.n Martin Drucker Nicole h. Lopez Aly.sa Carpenter James C. K. Ng Department of Plant Path.logy.and Microbiology and Center for Disease Vector Research University of California Riverside California USA INRA UMR BGPI Plant Pathogen Interactions Montpellier Cedex 5 France Barry.University Miami Florida USA East Stroudsburg University E. Stroudsburg Pennsylvania USA

Transmission of plant viruses by.ph.0}oph.gous h.mipteran insects encompasses complex interactions underly.ng a continuum of processes involved in virus acquisition, retention and inoculation combined with.vector feeding beh.vior. h.re, we investigated th. effects of dietary.ph.on wh.tefly.（Bemisia tabaci） feeding beh.vior and release of Lettuce infectious y.llows virus （LIy.） virions retained in th. vector＇s foregut. Electrical penetration graph.analy.is revealed th.t variables associated with.wh.tefly.probing and ingestion did not differ significantly.in ph.（4, 7.4, and 9） adjusted artificial diets. To investigate virus retention and release, wh.teflies allowed to acquire LIy. virions in a ph.7.4 artificial diet were fed ph.4, 7.4, or 9 virion-free artificial （clearing） diets. Immunofluorescent localization analy.es indicated th.t virions remained bound to th. foreguts of approximately.20%-24% of vectors after th.y.fed on each.of th. 3 ph. adjusted clearing diets. Wh.n RNA preparations from th. clearing diets were analy.ed by.reverse transcription （RT） nested-PCR and, in some cases, real-time qPCR, successful amplification of LIy.-specific sequence was infrequent but consistently.repeatable for th. ph.7.4 diet but never observed for th. ph.4 and 9 diets, suggesting a weak ph.dependent effect for virion release. Viruliferous vectors th.t fed on each.of th. 3 ph.adjusted clearing diets transmitted LIy. to virus-free plants. Th.se results suggest th.t ch.nges in ph.values alone in artificial diet do not result in observable ch.nges in wh.tefly.feeding beh.viors, an observation th.t marks a first in th. feeding of artificial diet by.wh.tefly.vectors; and th.t th.re is a potential causal and contingent relationsh.p between th. ph.in artificial diet and th. release/inoculation of foregut bound virions.

关键词： Crinivirus dietary.ph inoculation noncirculative semipersistent transmission retention wh.tefly