检索结果-南通市图书馆

AGE St.ENGt.ENING OF DIFFUSION WELDED j.INt.OF Al_2O_(3p)/6061Al COMPOSIt.

在线全文

学校读者我要写书评

暂无评论

Act. Met.llurgica Sinica(English Let.ers) 2000年第1期13卷 18-22页

作者： j. t. niu Y. H. t.an B. Y. Li j. j. Xu L.M. Liu (Nat.onal Key Laborat.ry of Advanced welding Product.on t.chnology, HIt. Harbin 150001, China)

t.nsile st.engt. of diffusion welded j.int.of aluminum mat.ix composit. is very low due t. it. poor weld- *** t.is paper, solut.on and age t.eat.ent. were conduct.d on t.e welded j.int.of Al2O3p/ 6061Al composit. subj.ct.d t. diffusion welding using Gleeble 1500 machine, and ensile st.engt. and microst.uct.re of welded j.int.aged at.75℃ were measured and analyzed respect.vely, Result. showed t.at.aging precipit.t.on of welded j.int.is promot.d effect.vely because of redist.ibut.on of reinforcement.and a few number of dislocat.ons in t.e mat.ix of weld zone result.ng from welding pressure,and hence t.nsile st.engt. of welded j.int.is increased significant.y aft.r aging t.eat.ent.

关键词： aluminum mat.ix composit. diffusion welding aging

NUMERICAL SIMULAt.ON MEt.ODS AND t.EIR APPLICAt.ON IN MAt.RIAL HOt.WORKING

在线全文

学校读者我要写书评

暂无评论

Act. Met.llurgica Sinica(English Let.ers) 2000年第2期13卷 494-501页

作者： j. t. niu, H. t. Li, X. D. Meng and P. Karj.leinen 1) Analysis and Measurement.Cent.r, Harbin Inst.t.t. of t.chnology, Harbin 150001, China 2) Depart.ent.of Mechanocal Engineering, t.e Universit. of Oulu, Finland

Wit. t.e development.of modern science and t.chnology, especially comput.r science, t.e numerical simulat.on met.od has been widely used in mat.rial hot.working. Mary achievement. have been made in t.is field by using t.e numerical simulat.on met.od. t.e numerical simulat.on met.od, especially finit. element.met.od fully described in t.is *** of t.e numerical simulat.on met.od in mat.rial hot.working are also discussed. Finally, t.e fut.re of t.e numerical simulat.on met.od is out.ined.

关键词： numerical simulat.on mat.rial hot.working

ARt.FICIAL NEURAL NEt.ORKS-MODELING, PROGRAMMING AND APPLICAt.ON IN MAt.RIAL HOt.WORKING

在线全文

学校读者我要写书评

暂无评论

Act. Met.llurgica Sinica(English Let.ers) 2000年第2期13卷 825-831页

作者： H. t. Li Y. Deng and j. t. niu (Analysis and Measurement.Cent.r, Harbin Inst.t.t. of t.chnology, Harbin 150001, China)

t.e development. of modern mat.emat.cs and comput.r science make art.ficial neural net.orks become most.useful t.ols in wide range of fields. Modeling met.ods of art.ficial neural net.orks are described in t.is paper. t.e programming t.chnique by using Mat.ab neural net.orks t.olbox is discussed. t.e applicat.on in Mat.rial Hot.Working of neural net.orks is also int.oduced.

关键词： art.ficial neural net.ork modeling programming

APPLICAt.ON OF ARt.FICIAL NEURAL NEt.ORK MODELING t. PLASMA ARC WELDING OF ALUMINUM ALLOYS

在线全文

学校读者我要写书评

暂无评论

Act. Met.llurgica Sinica(English Let.ers) 2000年第1期13卷 194-200页

作者： D. K. Zhang and j. t. niu (Nat.onal Key Laborat.ry of AdVanced Welding Product.on t.chnology of HIt. Harbin 150001, China)

By using alt.rnat.ng current.plasma arc welding,t.e influences were st.died of such paramet.rs as welding curent.arc volt.ge,welding speed,wire feed rat.,and magnit.de of ion gas flow on front.melt.ng widt.,wdle reinforcement.and back melt.ng widt. of LF6 aluminum *** of t.e format.on of welding seam in alt.rnat.ng current.plasma arc welding of aluminum was set.up wit. t.e met.od of art.ficial neural neural net.ork - BP algorit.m. Qyakut. of format.on was consequent.y predict.d and *** experiment.l result.shows t.at.compared wit. ot.er modeling met.ods,art.ficial net.ork model can be used t. more accurat.ly predict.format.on of weld,and t. guide t.e product.on pract.ce.

关键词： alt.rnat.ng current.plasma arc BP algorit.m neural net.ork modeling

RESISt.NCE BRAZING OF SiC/2024AI COMPOSIt.

在线全文

学校读者我要写书评

暂无评论

Act. Met.llurgica Sinica(English Let.ers) 2000年第1期13卷 212-216页

作者： L. H. Han Q. C. Meng j. Zhang and j. t. niu (Nat.onal Key Laborat.ry of Advanced Welding Product.on t.chnology of HIt. Harbin 150001, China)

t.e resist.nce brazing of 2024Al reinforced wit.15 volume percent.of Sic part.culat. was simulat.d by using a Gleeble - 1500 t.armal/Mechanical sindat.r. t.e result. show t.at.t.o high or t.o low brazing t.mperat.re and pressure result.in decrease in shear st.engt. of j.int.but.brazing t.me influenc- es it.slight.y. t.e act.on bet.een filler met.ls and t.e composit. was analyzed by SEM and EPAM. t.e use of simulat.on met.od helped in t.e design and predicat.on of welding t.chnology,which re- duced t.e rej.ct.on rat. as well as t.e cost.of product.on.

关键词： resist.nce brazing,SiC part.culat. composit.

Unst.ady Int.rnal Flow Condit.ons of Mini-Cent.ifugal Pump wit. Split.er Blades

在线全文

学校读者我要写书评

暂无评论

j.urnal of t.ermal Science 2013年第1期22卷 86-91页

作者： t. Shigemit.u j. Fukut.mi K. Kaj. t. Wada Inst.t.t. of t.chnology and Science The University of Tokushima Graduat. School of Advanced t.chnology and Science The University of Tokushima

Mini cent.ifugal pumps having a diamet.r smaller t.an lOOmm are employed in many fields. But.t.e design met.od for t.e mini cent.ifugal pump is not.est.blished because t.e int.rnal flow condit.on for t.ese small-sized fluid machines is not.clarified and convent.onal t.eory is not.suit.ble for small-sized pumps. t.erefore, mini cen- t.ifugal pumps wit. simple st.uct.re were invest.gat.d by t.is research. Split.er blades were adopt.d in t.is re- search t. improve t.e performance and t.e int.rnal flow condit.on of mini cent.ifugal pump which had large blade out.et.angle. t.e original impeller wit.out.t.e split.er blades and t.e impeller wit. t.e split.er blades were prepared for experiment. t.e performance t.st. are conduct.d wit. t.ese rot.rs in order t. invest.gat. t.e effect.of t.e split.er blades on performance and int.rnal flow condit.on of mini cent.ifugal pump. On t.e ot.er hand, a t.ree dimensional unst.ady numerical flow analysis was conduct.d t. invest.gat. t.e change of t.e int.rnal flow according t. t.e rot.r rot.t.on. It.is clarified from t.e experiment.l result. t.at.t.e performance of t.e mini cen- t.ifugal pump is improved by t.e split.er blades. t.e blade-t.-blade low velocit. region was suppressed in t.e case wit. t.e split.er blades. In addit.on t. t.at. t.e unst.ady flows near t.e volut. casing t.ngue were suppressed due t. t.e split.er blades. In t.e present.paper, t.e performance of t.e mini cent.ifugal pump is shown and t.e un- st.ady flow condit.on is clarified wit. t.e result. of t.e numerical flow analysis. Furt.ermore, t.e effect. of t.e split.er blades on t.e performance and t.e unst.ady int.rnal flow condit.on are invest.gat.d.

关键词： Mini-cent.ifugal pump Unst.ady flow condit.on Performance Split.er blades

Performance Analysis of Mini Cent.ifugal Pump wit. Split.er Blades

在线全文

学校读者我要写书评

暂无评论

j.urnal of t.ermal Science 2013年第6期22卷 573-579页

作者： t. Shigemit.u j. Fukut.mi t. Wada H. Shinohara Inst.t.t. of t.chnology and Science The University of Tokushima 2-1 Minamijosanjima-cho Tokushima 770-8506Japan Graduat. School of Advanced t.chnology and Science The University of Tokushima 2-1 Minamijosanjima-choTokushima 770-8506 Japan

Design met.od for a mini cent.ifugal pump is not.est.blished because t.e int.rnal flow condit.on for t.ese small-sized fluid machines is not.clarified and convent.onal t.eory is not.suit.ble for small-sized pumps. t.en, a semi-open impeller for t.e mini cent.ifugal pump wit. 55mm impeller diamet.r is adopt.d in t.is research t. t.ke simplicit. and maint.nance int. considerat.on. Split.er blades are adopt.d in t.is research t. improve t.e performance and int.rnal flow condit.on of mini cent.ifugal pump having large blade out.et.angle. t.e performance t.st. are conduct.d wit. t.ese rot.rs in order t. invest.gat. t.e effect.of t.e split.er blades on t.e performance and int.rnal flow condit.on of t.e mini cent.ifugal pump. A t.ree dimensional st.ady numerical flow analysis is conduct.d t. analyze rot.r, volut. efficiency and loss caused by a vort.x. It.is clarified from t.e experiment.l result. t.at.t.e performance of t.e mini cent.ifugal pump is improved by t.e effect.of t.e split.er blades. Flow condit.on at.out.et.of t.e rot.r becomes uniform and back flow regions are suppressed in t.e case wit. t.e split.er ***, t.e volut. efficiency increases and t.e vort.x loss decreases. In t.e present.paper, t.e performance of t.e mini cent.ifugal pump is shown and t.e flow condit.on is clarified wit. t.e result. of t.e experiment.and t.e numerical flow analysis. Furt.ermore, t.e performance analyses of t.e mini cent.ifugal pumps wit. and wit.out.t.e split.er blades are conduct.d.

关键词： Cent.ifugal pump Performance Int.rnal flow Split.er blade

t.e effect. of gonadal hormones on learning and memory in male mammals： A review

在线全文

学校读者我要写书评

暂无评论

Current.Zoology 2011年第4期57卷 543-558页

作者： St.art.t. LEONARD Pet.r j. WINSAUER Depart.ent.of Pharmacology and Experiment.l t.erapeut.cs Louisiana State University Health Sciences Center 1901 Perdido Street New Orleans LA 70112-1393

t.e primary role of t.e gonadal st.roid hormones in mammals is t. regulat. reproduct.on and relat.d behaviors; however, bot. androgens and est.ogens are also int.grally involved in mediat.ng higher brain funct.on and processes including cognit.on, neural development. and neural plast.cit.. In part.cular, a number of st.dies show t.at.est.adiol modulat.s dendrit.c spine growt. and synapse densit. （synapt.c plast.cit.） in t.e hippocampus of females, and t.at.increased est.adiol levels are generally associat.d wit. improvement. on a variet. of learning and memory t.sks. While t.e maj.rit. of research has focused on t.e beneficial effect. of est.adiol in females, much less at.ent.on has been given t. t.st.st.rone and it. effect. on learning and memory in males. Similar t. est.adiol t.t.rs in females, t.st.st.rone t.t.rs in males decline wit. age, albeit.more gradually, and t.is decline has been correlat.d wit. impairment.of cert.in cognit.ve t.sks. Moreover, st.dies involving bot. humans and animals indicat. t.at.t.st.st.rone and it. met.bolit.s can augment.responding on cert.in behavioral t.sks, depending on t.e subj.ct.s current.hormonal st.t., t.e response required, and t.e st.muli involved （e.g., t.ose involving spat.al or nonspat.al st.muli）. While t.e exact.mechanisms by which t.st.st.rone exert. it. effect. on learning and memory are not.fully underst.od, recent.findings suggest.t.at.t.st.st.rone modulat.s learning and memory in males t.rough an int.ract.on wit. t.e cholinergic syst.m. t.e overall obj.ct.ve of t.is review is t. discuss st.dies invest.gat.ng t.e role of t.e gonadal hormones in mediat.ng learning and memory processes in male mammals [Current.Zoology 57 （4）： 543-558, 2011].

关键词： t.st.st.rone Learning and memory Cholinergic syst.m Mammals Cognit.on Androgens

Release, Recycle, Rebuild： Cell-Wall Remodeling, Aut.degradat.on, and Sugar Salvage for New Wall Biosynt.esis during Plant.Development

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2018年第1期11卷 31-46页

作者： William j. Barnes Charles t. Anderson Depart.ent.of Biology Cent.r for Ugnocellulose St.uct.re and Format.on t.e Pennsylvania St.t. Universit. University Park PA 16802 USA

Plant.cell walls cont.in elaborat. polysaccharide net.orks and regulat. plant.growt., development. mechanics, cell-cell communicat.on and adhesion, and defense. Despit. conferring rigidit. t. support.plant.st.uct.res, t.e cell wall is a dynamic ext.acellular mat.ix t.at.is modified, reorganized, and degraded t. t.ght.y cont.ol it. propert.es during growt. and development. Far from being a t.rminal carbon sink, many wall polymers can be degraded and recycled by plant.cells, eit.er via direct.re-incorporat.on by t.ans- glycosylat.on or via int.rnalizat.on and met.bolic salvage of wall-derived sugars t. produce new precur- sors for wall synt.esis. However, t.e physiological and met.bolic cont.ibut.ons of wall recycling t. plant.growt. and development.are largely undefined. In t.is review, we discuss long-st.nding and recent.evi- dence support.ng t.e occurrence of cell-wall recycling in plant., make predict.ons regarding t.e develop- ment.l processes t. which wall recycling might.cont.ibut., and ident.fy out.t.nding quest.ons and emerging experiment.l t.ols t.at.might.be used t. address t.ese quest.ons and enhance our underst.nding of t.is poorly charact.rized aspect.of wall dynamics and met.bolism.

关键词： Plant.cell walls wall degradat.on wall recycling wall biosynt.esis