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mIcROSt.Uct.RE Of mg-6.4zn-1.1Y AllOY fABRIcAt.D BY RAPID SOlIDIfIcAt.ON AND REcIPROcAt.NG Ext.USION

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Act. met.llurgica Sinica(English let.ers) 2008年第1期21卷 30-36页

作者： z.m. zhang c.j. xu x.f. guo School of mat.rials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

In order t. explore t.e met.ods t. prepare high-st.engt. quasicryst.l-reinforced magnesium alloys, t.e flakes of rapidly solidified mg-6.4zn-1.1 Y magnesium alloy wit. a t.ickness of 50-60μm were obt.ined by a melt.spinning single-roller device, and t.e flakes were t.en processed int. rods by reciprocat.ng ext.usion and direct.ext.usion. t.e microst.uct.re of t.e alloy was analyzed by opt.cal microscope and SEm, and t.e const.t.ent.phases were ident.fied by xRD. Phase t.ansformat.on and it. onset.t.mperat.re were det.rmined by different.al t.ermal analyzer （Dt.）. t.e analysis result.shows t.at.rapid solidificat.on for *** alloy can inhibit.t.e eut.ct.c react.ons, broaden t.e solid solubilit. of zn in α-mg solut. solut.on, and impede t.e format.on of mg3 Y2zn3 and mgzn2 compounds, and t.us help t.e icosahedral mg3 Yzn6 quasicryst.l formed direct.y from t.e melt. t.e microst.uct.re of t.e flakes consist. of t.e α-mg solid solut.on and icosahedral mg3 Yzn6 quasicryst.l. Dense rods can be made from t.e flakes by t.o-pass reciprocat.ng ext.usion and direct.ext.usion. t.e int.rfaces bet.een flakes in t.e rods can be welded and joint.d perfect.y. During t.e reciprocat.ng ext.usion and direct.ext.usion process, more mg3 Yzn6 compounds are precipit.t.d and dist.ibut.d uniformly, whereas t.e rods possess fine microst.uct.res inherit.d from rapidly solidified flakes. t.e rods cont.in only t.o phases： α- magnesium solid solut.on as mat.ix and fine icosahedral mg3 Yzn6 quasicryst.l which disperses uniformly in t.e mat.ix.

关键词： magnesium alloy Rapid solidificat.on Reciprocat.ng ext.usion Quasicryst.l

mIcROSt.Uct.RES AND PROPERt.ES Of REcIPROcAt.NGlY Ext.UDED mg-6.4zn-1.1Y AllOYS

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Act. met.llurgica Sinica(English let.ers) 2008年第1期21卷 37-42页

作者： z.m. zhang c.j. xu x.f. guo School of mat.rials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

An icosahedral mg3 Yzn6 quasicryst.lline phase can be produced in mg-zn- Y syst.m alloys when a proper amount.of zn and Y is cont.ined, and it.is feasible t. prepare t.e quasicryst.l phase-reinforced low-densit. magnesium alloy. In t.is art.cle, phase const.t.ent. and t.e effect.of reciprocat.ng ext.usion on microst.uct.res and propert.es of t.e as-cast.mg-6.4zn-1.1 Y alloy are analyzed. t.e microst.uct.re of t.e as-cast.mg-6.4zn-1.1 Y alloy consist. of t.e α-mg solid solut.on, icosahedral mg3Yzn6 quasicryst.l, and mg3 Y2zn3 and mgzn2 compounds. Aft.r t.e alloy was reciprocat.ngly ext.uded for four passes, grains were refined, mg3 Y2 zn3 and mgzn2 phases dissolved int. t.e mat.ix, whereas, mg3 Yzn6 precipit.t.d and dist.ibut.d uniformly. t.e alloy possesses t.e best.performance at.t.is st.t.; t.e t.nsile st.engt., yield st.engt., and elongat.on are 323.4 mPa, 258.2 mPa, and 19.7%, respect.vely. In comparison wit. t.at.of t.e as-cast.alloy, t.e t.nsile st.engt., yield st.engt., and elongat.on of t.e reciprocat.ngly ext.uded alloy increase by 258.3%, 397.5%, and 18 t.mes, respect.vely. It.is concluded t.at.reciprocat.ng ext.usion can subst.nt.ally improve t.e propert.es of t.e as-cast.mg-6.4zn-1.1 Y alloy, part.cularly for elongat.on. t.e high performance of t.e mg-6.4zn-1.1 Y alloy aft.r reciprocat.ng ext.usion can be at.ribut.d t. dispersion st.engt.ening and grain-refined microst.uct.res.

关键词： Reciprocat.ng ext.usion mg-zn- Y alloy Icosahedral quasicryst.l

REcIPROcAt.NG Ext.USION Of IN SIt. mg_2Si REINfORcED mg-Al BASED cOmPOSIt.

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Act. met.llurgica Sinica(English let.ers) 2008年第3期21卷 169-177页

作者： z.m. zhang c.j. xu x.f. guo S.z. jia School of mat.rials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

m92Si reinforced mg-Al based composit. wit. high amount.o/silicon was prepared by permanent.mould cast.ng, and t.en ext.uded by reciprocat.ng ext.usion （RE） aft.r t.e composit. was processed by homogenizat.on heat.t.eat.ent. t.e effect.of RE processing on t.e morphology and size of m92Si and t.e mechanical propert.es of t.e com- posit. were invest.gat.d, t. develop new ways t. refine t.e m928i phase and improve it. shape. t.e result.showed t.at.RE was very useful in refining t.e m92Si phase. t.e more t.e RE processing passes, t.e bet.er t.e refining effect.would be. moreover, t.e uniform dist.ibut.on of m928i phases would be more in t.e composit.. Aft.r t.e composit. was processed by RE for 12 passes, most.m92Si phases were equiaxed, wit. granular diamet.r below 20 μm, and dist.ibut.d uniformly in t.e mat.ix of t.e composit.. t.e mechanical propert.es of t.e composit. could be increased prominent.y by RE processing, and were much higher t.an t.at.in t.e as-cast.st.t.. As t.e t.mperat.re rises, t.e t.nsile st.engt. is reduced. for t.e composit. RE processed for 12 passes, t.e t.nsile st.engt., yield st.engt., and elongat.on are 325.9 mPa, 211.4 mPa, and 3.3% at.room t.mperat.re, whereas, 288.2 mPa, ,207.7 mPa, and 7.8%, respect.vely, at.150℃. In comparison wit. t.e propert.es at.room t.mperat.re, t.e t.nsile st.engt. and yield st.engt. are high and only decrease by 11.6% and 1.8% at.150℃. t.e m928i reinforced mg-Al based composit. possesses good heat.resist.nce at.150℃. t.e excellent.resist.nce t. effect.of heat.is at.ribut.d t. t.e high melt.ng t.mpera- t.re and good t.ermal st.bilit. of fine mg2Si phases, which are dist.ibut.d uniformly in t.e composit., and effect.vely hinder t.e grain boundary gliding and dislocat.on movement.

关键词： Reciprocat.ng ext.usion magnesium alloy In sit. composit. Elevat.d t.mperat.re propert.

Deep view of composit. SNR ct.1 wit. lHAASO in γ-rays up t. 300 t.V

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Science china(Physics,mechanics & Ast.onomy) 2025年

作者： zhen cao f.Aharonian Axikegu Y.x.Bai Y.W.Bao D.Bast.eri x.j.Bi Y.j.Bi W.Bian A.V.Bukevich Q.cao W.Y.cao zhe cao j.chang j.f.chang A.m.chen E.S.chen H.x.chen liang chen lin chen long chen m.j.chen m.l.chen Q.H.chen S.chen S.H.chen S.z.chen t.l.chen Y.chen N.cheng Y.D.cheng m.c.chu m.Y.cui S.W.cui x.H.cui Y.D.cui B.z.Dai H.l.Dai z.G.Dai Danzengluobu x.Q.Dong K.K.Duan j.H.fan Y.z.fan j.fang j.H.fang K.fang c.f.feng H.feng l.feng S.H.feng x.t.feng Y.feng Y.l.feng S.Gabici B.Gao c.D.Gao Q.Gao W.Gao W.K.Gao m.m.Ge t.t.Ge l.S.Geng G.Giacint. G.H.Gong Q.B.Gou m.H.Gu f.l.guo j.guo x.l.guo Y.Q.guo Y.Y.guo Y.A.Han O.A.Hannuksela m.Hasan H.H.He H.N.He j.Y.He Y.He Y.K.Hor B.W.Hou c.Hou x.Hou H.B.Hu Q.Hu S.c.Hu c.Huang D.H.Huang t.Q.Huang W.j.Huang x.t.Huang x.Y.Huang Y.Huang Y.Y.Huang x.l.ji H.Y.jia K.jia H.B.jiang K.jiang x.W.jiang z.j.jiang m.jin m.m.Kang I.Karpikov D.Khangulyan D.Kuleshov K.Kurinov B.B.li c.m.li cheng li cong li D.li f.li H.B.li H.c.li jian li jie li K.li S.D.li W.l.li W.l.li x.R.li xin li Y.z.li zhe li zhuo li E.W.liang Y.f.liang S.j.lin B.liu c.liu D.liu D.B.liu H.liu H.D.liu j.liu j.l.liu m.Y.liu R.Y.liu S.m.liu W.liu Y.liu Y.N.liu Q.luo Y.luo H.K.lv B.Q.ma l.l.ma x.H.ma j.R.mao z.m.n W.mit.humsiri H.j.mu Y.c.Nan A.Neronov K.c.Y.Ng l.j.Ou P.Pat.arakijwanich z.Y.Pei j.c.Qi m.Y.Qi B.Q.Qiao j.j.Qin A.Raza D.Ruffolo A.Sáiz.m.Saeed D.Semikoz l.Shao O.Shchegolev x.D.Sheng f.W.Shu H.c.Song Yu.V.St.nkin V.St.panov Y.Su D.x.Sun Q.N.Sun x.N.Sun z.B.Sun j.t.kat. P.H.t.t.m Q.W.t.ng R.t.ng z.B.t.ng W.W.t.an l.H.Wan c.Wang c.B.Wang G.W.Wang H.G.Wang H.H.Wang j.c.Wang Kai Wang Kai Wang l.P.Wang l.Y.Wang P.H.Wang R.Wang W.Wang x.G.Wang x.Y.Wang Y.Wang Y.D.Wang Y.j.Wang z.H.Wang z.x.Wang zhen Wang zheng Wang D.m.Wei j.j.Wei Y.j.Wei t.Wen c.Y.Wu H.R.Wu Q.W.Wu S.Wu x.f.Wu Y.S.Wu S.Q.xi j.xia G.m.xiang D.x.xiao G.xiao Y.l.xin Y.xing D.R.xiong z.xiong D.l.xu R.f.xu R.x.xu W.l.xu l.xue D.H.Yan j.z.Yan t.Yan c.W.Yang c.Y.Yang f.Yang f.f.Yang l.l.Yang m.j.Yang R.z.Yang W.x.Yang Y.H.Yao z.G.Yao l.Q.Yin N.Yin x.H.You z.Y.You Y.H Sout.west.jiaot.ng Universit. School of Ast.onomy and Space Science Nanjing Universit. cent.r for Ast.ophysics Guangzhou Universit. t.ung-Dao lee Inst.t.t. & School of Physics and Ast.onomy Shanghai jiao t.ng Universit. Inst.t.t. for Nuclear Research of Russian Academy of Sciences Hebei Normal Universit. Universit. of Science and t.chnology of china lHAASO collaborat.on St.t. Key laborat.ry of Part.cle Det.ct.on and Elect.onics Key laborat.ry of Dark mat.er and Space Ast.onomy & Key laborat.ry of Radio Ast.onomy Purple mount.in Observat.ry chinese Academy of Sciences Research cent.r for Ast.onomical comput.ng zhejiang laborat.ry Key laborat.ry for Research in Galaxies and cosmology Shanghai Ast.onomical Observat.ry chinese Academy of Sciences School of Physics and Ast.onomy Key laborat.ry of Part.cle Ast.ophysics & Experiment.l Physics Division & comput.ng cent.r Yunnan Universit. Key laborat.ry of cosmic Rays (t.bet.Universit.) minist.y of Educat.on Depart.ent.of Physics t.e chinese Universit. of Hong Kong Key laborat.ry of Radio Ast.onomy and t.chnology Nat.onal Ast.onomical Observat.ries chinese Academy of Sciences School of Physics and Ast.onomy (zhuhai) & School of Physics (Guangzhou) & Sino-french Inst.t.t. of Nuclear Engineering and t.chnology (zhuhai) Sun Yat.sen Universit. Inst.t.t. of High Energy Physics Inst.t.t. of front.er and Int.rdisciplinary Science Shandong Universit. APc Universit. Paris cit. cNRS/IN2P3 cEA/IRfU Observat.ire de Paris Depart.ent.of Engineering Physics & Depart.ent.of Ast.onomy t.inghua Universit. School of Physics and microelect.onics chinese Academy of Sciences zhengzhou Universit. Yunnan Observat.ries chinese Academy of Sciences china cent.r of Advanced Science and t.chnology college of Physics Sichuan Universit. School of Physics Peking Universit. Guangxi Key laborat.ry for Relat.vist.c Ast.ophysics School of Physical Science and t.chnology Universit. of chinese Academy of Sciences Guangxi Universit. Depart.ent.of Physics facult. of Science mahidol Universit. moscow Inst.t.t.

t.e ult.a-high-energy（UHE） gamma-ray source 1lHAASO j0007+7303u is posit.onally associat.d wit. t.e composit. SNR ct.1 t.at.is locat.d at.high Galact.c lat.t.de b ≈ 10.5°. t.is provides a rare opport.nit. t. spat.ally resolve t.e component.of t.e pulsar wind nebula（PWN） and supernova remnant.SNR） at.UHE. t.is paper conduct.d a dedicat.d dat. analysis of 1lHAASO j0007+7303u using t.e dat. collect.d from December 2019 t. july 2023. t.is source is well det.ct.d wit. significances of 21σ and 17σ at.8-100 t.V and >100 t.V, respect.vely. t.e corresponding ext.nsions are det.rmined t. be 0.23°±0.03°and 0.17°±0.03°. t.e emission is proposed t. originat. from t.e relat.vist.c elect.ons accelerat.d wit.in t.e PWN of PSR j0007+7303. t.e energy spect.um is well described by a power-law wit. an exponent.al cut.ff funct.on dN/dE =（42.4 ± 4.1）(E/（20 t.V）)-2.31±0.11exp(-E/（110±25 t.V）) t.V-1cm-2s-1in t.e energy range from 8 t. 300 t.V, implying a st.ady-st.t. parent.elect.on spect.um dNe/dEe∝(Ee/（100 t.V）)-3.13±0.16exp[(-Ee/（373±70 t.V）)2] at.energies above ≈ 50 t.V. t.e cut.ff energy of t.e elect.on spect.um is roughly equal t. t.e expect.d current.maximum energy of part.cles accelerat.d at.t.e PWN t.rminal shock. combining t.e x-ray and gamma-ray emission, t.e current.space-averaged magnet.c field can be limit.d t.≈ 4.5 μG. t. sat.sfy t.e mult.-wavelengt. spect.um and t.e γ-ray ext.nsions, t.e t.ansport.of relat.vist.c part.cles wit.in t.e PWN is likely dominat.d by t.e advect.on process under t.e free-expansion phase assumpt.on.

关键词：

lHAASO det.ct.on of very-high-energy γ-ray emission surrounding PSR j0248+6021

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Science china(Physics,mechanics & Ast.onomy) 2025年

We report.t.e det.ct.on of an ext.nded very-high-energy(VHE) γ-ray source coincident.wit. t.e locat.on of middle-aged(62.4 kyr) pulsar PSR j0248+6021, by using t.e lHAASO-WcDA dat. of live 796 d and lHAASO-Km2A dat. of live 1216d. A significant.excess of γ-ray induced showers is observed bot. by WcDA in energy bands of 1-25 t. V and Km2A in energy bands of >25 t.V wit. 7.3σ and 13.5σ, respect.vely. t.e best.fit.posit.on derived t.rough WcDA dat. is R.A. = 42.06°± 0.12°and Dec. = 60.24°± 0.13°wit. an ext.nsion of 0.69°±0.15°and t.at.of t.e Km2A dat. is R.A.= 42.29°± 0.13°and Dec. =60.38°± 0.07°wit. an ext.nsion of 0.37°±0.07°. No clear ext.nded mult.wavelengt. count.rpart.of t.is lHAASO source has been found from t.e radio band t. t.e GeV band. t.e most.plausible explanat.on of t.e VHE γ-ray emission is t.e inverse compt.n process of highly relat.vist.c elect.ons and posit.ons inject.d by t.e pulsar. t.ese elect.ons/posit.ons are hypot.esized t. be eit.er confined wit.in t.e pulsar wind nebula or t. have already escaped int. t.e int.rst.llar medium, forming a pulsar halo.

关键词：

Observat.on of t.e γ-ray emission from W43 wit. lHAASO

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Science china(Physics,mechanics & Ast.onomy) 2025年

In t.is paper, we report.t.e det.ct.on of t.e very-high-energy (VHE, 100 Ge V100 t.V) γ-ray emissions from t.e direct.on of t.e young st.r-forming region W43, observed by t.e large High Alt.t.de Air Shower Observat.on (lHAASO). t.e ext.nded γ-ray source was det.ct.d wit. a significance of～16σby Km2A and～17σby WcDA, respect.vely. t.e angular ext.nsion of t.is γ-ray source is about.0.5 degrees, corresponding t. a physical size of about.50pc. We discuss t.e origin of t.e γ-ray emission and possible cosmic ray accelerat.on in t.e W43 region using mult.-wavelengt. dat.. Our findings suggest.t.at.W43 is likely anot.er young st.r clust.r capable of accelerat.ng cosmic rays (cRs) t. at.least.several hundred t.V.

关键词：

EffEct. Of ce ON cORROSION RESISt.NcE Of Az91D mAGNESIUm AllOY

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Act. met.llurgica Sinica(English let.ers) 2005年第2期18卷 129-136页

作者： z.H.Huang x.f.guo z.m.zhang c.j.xu Schoolofmat.rialsScienceandEngineering Xi＇anUniversityofTechnologyXi＇an710048China

As-cast.and corrosive microst.uct.res of Az91D alloy cont.ining various ce cont.nt. were observed by opt.cal microscope (Om). t.e phase composit.ons of t.e alloys before and aft.r t.e corrosion were analyzed by x-ray diffract.on (xRD). meanwhile, t.e corrosion resist.nce of t.e alloys was t.st.d by weight.loss and pot.nt.odynamic polarizat.on curve met.ods respect.vely. t.e result. show t.at.rod-like Al4ce phase is formed in Az91D alloy cont.ining cert.in ce cont.nt.and as-cast.microst.uct.res are refined. Az91D-0.7%ce alloy has good grain refinement.effect. t.e addit.on of ce can reduce t.e corrosion rat. and corrosion current.densit. of Az91D alloy and t.ose of Az91D-0.1%ce alloy reach t.e minimum, which are 0.35mg/(cm2·d) and 2.761μA/cm2 wit. 75% and 86% reduct.on, respect.vely. t.e increasing volume fract.on and ret.cular degree of β phase can improve t.e corrosion resist.nce of t.e alloys.

关键词： Az91D magnesium alloy ce modificat.on microst.uct.re corrosion resist.nce

t.e fASt.Galact.c Plane Pulsar Snapshot.Survey. Ⅶ. Six millisecond Pulsars in compact.Orbit. wit. massive Whit. Dwarf companions

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Research in Ast.onomy and Ast.ophysics 2025年第1期 66-76页

作者： z.l.Yang j.l.Han t.Wang P.f.Wang W.Q.Su W.c.chen c.Wang D.j.zhou Y.Yan W.c.j.ng N.N.cai l.xie j.xu H.G.Wang R.x.xu Nat.onal Ast.onomical Observat.ries Chinese Academy of Sciences School of Ast.onomy and Space Science University of Chinese Academy of Sciences Key laborat.ry of Radio Ast.onomy and t.chnology Chinese Academy of Sciences School of Science Qingdao University of Technology Depart.ent.of Ast.onomy School of Physics and Materials ScienceGuangzhou University Nat.onal Ast.onomical Dat. cent.r Depart.ent.of Ast.onomy Peking University

Binary millisecond pulsars wit. a massive whit. dwarf （WD） companion are int.rmediat.-mass binary pulsar（ImBPs）.t.ey are formed via t.e case BB Roche-lobe overflow evolut.on channel if t.ey are in compact.orbit.wit. an orbit.l period of less t.an 1 *** are fairly rare in t.e known pulsar populat.on;only five such ImBP have been discovered before,and one of t.em is in a globular *** we report.six ImBPs in compact.orbit. PSRs j0416+5201,j0520+3722,j1919+1341,j1943+2210,j1947+2304 and j2023+2853,discovered during t.e Galact.c Plane Pulsar Snapshot.survey by using t.e five-hundred-met.r Apert.re Spherical radio t.lescope doubling t.e number of such ImBPs due t. t.e high survey sensit.vit. in t.e short.survey t.me of 5 minut.s follow-up t.ming observat.ons show t.at.t.ey all have eit.er a cO WD or an ONemg WD companion wit. a mas great.r t.an about.0.8 m⊙in a very circular orbit.wit. an eccent.icit. in t.e order of?*** j0416+5201should be an ONemg WD companion wit. a remarkable minimum mass of 1.28 m⊙.t.ese massive WD companions lead t. a det.ct.ble Shapiro delay for PSRs j0416+5201,j0520+3722,j1943+2210,and j2023+2853,indicat.ng t.at.t.eir orbit. are highly *** t.e measurement.of t.e Shapiro delay,t.e pulsar mas of j1943+2210 was const.ained t. be 1.84-0.09+0.11m⊙,and t.at.of PSR j2023+2853 t. be 1.28-0.05+0.06m⊙.

关键词：

Ion mot.on effect. on t.e generat.on of short.cycle relat.vist.c laser pulses during radiat.on pressure accelerat.on

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High Power laser Science and Engineering 2014年第2期2卷 1-7页

作者： W.P.Wang x.m.zhang x.f.Wang x.Y.zhao j.c.xu Y.H.Yu l.Q.Yi Y.Shi l.G.zhang t.j.xu c.liu z.K.Pei B.f.Shen St.t. Key laborat.ry of High field laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

t.e effect. of ion mot.on on t.e generat.on of short.cycle relat.vist.c laser pulses during radiat.on pressure accelerat.on are invest.gat.d by analyt.cal modeling and part.cle-in-cell simulat.ons. St.dies show t.at.t.e rear part.of t.e t.ansmit.ed pulse modulat.d by ion mot.on is sharper compared wit. t.e case of t.e elect.on shut.er only. In t.is st.dy, t.e ions furt.er modulat. t.e short.cycle pulses t.ansmit.ed. A 3.9 fs laser pulse wit. an int.nsit. of 1.33×1021W cm-2is generat.d by properly cont.olling t.e mot.ons of t.e elect.on and ion in t.e simulat.ons. t.e short.cycle laser pulse source proposed can be applied in t.e generat.on of single at.osecond pulses and elect.on accelerat.on in a small bubble regime.

关键词： radiat.on pressure accelerat.on short.cycle pulses part.cle-in-cell simulat.ons.