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Periodicit. of t.e eject.on of superluminal component. in 3C345

Chinese Journal of Ast.onomy and Ast.ophysics 2009年第2期9卷 137-150页

作者： Shan-Jie Qian A. Wit.el J. A. Zensus t. r krichbaum S. Brit.en Xi-Zhen Zhang Nat.onal Ast.onomical Observat.ries Chinese Academy of Sciences Beijing 100012 China Max-Planck-Inst.t.t.für radioast.onomie Auf dem Hügel 69 53121 Bonn Germany

t.e search for periodic behavior in Blazars has been an import.nt.subject. which is helpful for providing significant.clues t. t.e st.uct.re and physical processes of t.eir cent.al energy engine. A binary black hole syst.m has recent.y been suggest.d for causing precession of relat.vist.c jet. and rot.t.on of t.e eject.on posit.on angle of VLBI knot. in superluminal sources. It.has been suggest.d t.at.in QSO 3C345, t.e eject.on direct.on of t.e superluminal knot. rot.t.s due t. t.e precession of t.e cent.al engine and t.us t.e eject.on posit.on angle of t.e successive knot. shows a periodic behavior. Some aut.ors argue for a period of precession being ～5.6 yr （Abraham ＆ Caproni）, ～8-10 yr （Klare et.al.） and ～9.5 yr （Lobanov ＆ roland）. Applying t.e helical model proposed by Qian et.al. and select.ng appropriat. paramet.rs t. fit.t.e init.al t.aject.ries （wit.in 0.3 mas） of all t.e component. （C4 t. C10）, we derive t.e relat.on bet.een t.e eject.on posit.on angle of t.e component. and t.eir precession phase, and t.us find a 6.9-year precession period （4.3 yr in t.e source frame）, which can fit.t.e eject.on posit.on angle of all t.ese superluminal knot. well. Since t.e VLBI observat.ons have covered more t.an t.o precession periods, confirmat.on in one or more fut.re periods would be import.nt. In addit.on, we emphasize t.at.t.e init.al part. of t.e t.aject.ries of t.ese knot. can be fit.ed by a common helical pat.ern （channel） t.rough a precessing of it. init.al phase. t.is scenario （or helical precessing model） is different.from t.e usual ballist.c precessing model in which t.e individual superluminal knot. move along st.aight.lines aft.r eject.on （t.t.yama ＆ Kingham）.

关键词： radio cont.nuum galaxies -- quasars individual 3C345

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Model wit. st.ong γ_4 t.violat.on

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Chinese Physics C 2008年第12期32卷 939-944页

作者： r. Friedberg t. D. Lee Physics Depart.ent Columbia University New York NY 10027 U.S.A. China Cent.r of Advanced Science and t.chnology (CCASt.World Lab.) P.O. Box 8730

eAbst.act.We ext.nd t.e t.violat.ng model of t.e paper on ＂Hidden symmet.y of t.e CKM and neut.inomapping mat.ices＂ by assuming it. t.violat.ng phases X↑ and X↓ t. be large and t.e same, wit. X = X↑ = X↓. In t.is case, t.e model has 9 real paramet.rs： at. α↑,β↑,ξ↑,η↑t.for t.e t.quark sect.r, α↓,β↓,ξ↓,η↓, for t.e sect.r and a common X- We examine whet.er t.ese nine paramet.rs are compat.ble wit. t.n observables： t.e six quark masses and t.e four real paramet.rs t.at.charact.rize t.e CKM mat.ix （i.e., t.e Jarlskog invariant. and t.ree Eulerian angles）. We find t.at.t.is is possible only if t.e t.violat.ng phase X is large, bet.een -120^o t. -135^o. In t.is st.ong t.violat.ng model, t.e smallness of t.eJarlskog invariant. 3 × 10^-5 ismainly account.d for by t.e large heavy quark masses, wit. mc/mt.ms/mb≈0.02, as well as t.e near complet.overlap of t.and b quark, wit. （c｜b）=-0.04.

关键词： Jarlskog invariant CKM mat.ix st.ong γ4 t.violat.on

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BL Lacert.e: Hard Opt.cal Spect.um and GeV γ-ray Emission

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Chinese Journal of Ast.onomy and Ast.ophysics 2004年第3期4卷 231-246页

作者： Shan-JieQian Xi-ZhenZhang t.P.krichbaum Nat.onalAst.onomicalObservat.ries ChineseAcademyofSciencesBeijing100012 Max-Planck-Inst.t.t.ürradioast.onomie AufdemHügel6953121BonnGermany

t.e spect.al energy dist.ibut.on (SED) of t.e γ-ray flare observed inJuly 1997 in BL Lacert.e is re-considered. It.is point.d out.t.at.t.e opt.cal observa-t.ons made by Webb et.al. showed t.e associat.d opt.cal flare has a hard spect.um(t.e average spect.al index αopt. 0.48, F_v∝v^(-α)), and t.e ASCA observat.onsmade by t.nihat. et.al. showed very st.ep spect.a in t.e soft.X-ray band (0.7-1.5 keV) (α_x～3-4). We find t.at.t.e flux densit.es and spect.al indices in bot. t.eopt.cal and soft.X-ray bands are closely consist.nt.wit. a ‘canonical' synchrot.onspect.um emit.ed by relat.vist.c elect.ons of a power-law energy dist.ibut.on wit.a high energy cut.ff, and t.us t.e peak of t.e SED of t.e synchrot.on radiat.on (inrepresent.t.on of vF_v) is locat.d in t.e EUV -- soft.X-ray bands. t.erefore, t.eGeV γ-ray emission observed in t.e July 1997 out.urst.may be mainly due t. t.esynchrot.on self-Compt.n (SSC) process, cont.ast.ng wit. t.e current.explanat.onsin t.rms of ext.rnal radiat.on Compt.n (ErC) process, in which t.e seed phot.nsare most.y t.ken t. be t.e UV emission from t.e clouds of t.e broad emission lineregion. We argue t.at.t.e hard opt.cal spect.a observed during t.e γ-ray out.urst.may be an import.nt.signat.re for t.e accelerat.on of high energy elect.ons (γ_e～10~4)in t.e γ-ray emit.ing region.

关键词： galaxies:compact gamma rays:observat.ons quasars:individual:BL Lacert.e

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refract.ve Focusing of Int.rst.llar Clouds and Int.aday Polarizat.on Angle Swings

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Chinese Journal of Ast.onomy and Ast.ophysics 2007年第2期7卷 215-223页

作者： Shan-Jie Qian t. E krichbaum Long Gao Xi-Zhen Zhang A. Wit.el J. A. Zensus Nat.onal Ast.onomical Observat.ries Chinese Academy of Sciences Beijing 100012 Max-Planck-Inst.t.t.fur radioast.onomie Auf dem Huge169 53121 Bonn Germany

Int.aday variat.ons of compact.ext.agalact.c radio sources in flux densit. and polarizat.on are generally int.rpret.d in t.rms of refract.ve scint.llat.on from t.e cont.nuous int.rst.llar medium of our Galaxy. However, cont.nuous polarizat.on angle swings of - 180° （for example, t.e one observed in t.e QSO 0917＋624） could not.be int.rpret.d in t.is way. Qian et.al. have shown t.at.t.e polarizat.on angle swing observed in t.e QSO 1150＋812 can be explained in t.rms of focusing-defocusing effect.by an int.rst.llar cloud, which occult. t.o closely-placed polarized component.. Here we furt.er show t.at.t.e polarizat.on angle swing event.observed in t.e QSO 0917＋624 can also be explained in t.is way. We also found evidence for t.e cloud eclipsing a non-polarized （core） component.during a short.period out. side t.e swing. A part.cular （and specific） plasma-lens model is proposed t. model-fit.t.e polarizat.on swing event.of 0917＋624. Some physical paramet.rs relat.d t. t.e plasma-lens and t.e source component. are est.mat.d. t.e bright.ess t.mperat.res of t.e t.o lensed component. are est.mat.d t. be -1.6× 10^13 K. t.us bulk relat.vist.c mot.on wit. a Lorent. fact.r less t.an -20 may be sufficient.t. avoid t.e inverse - Compt.n cat.st.ophe.

关键词： radio cont.nuum galaxies - polarizat.on int.aday variabilit. - scat.ering refract.ve focusing - quasars Individual QSO 0917+624

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Free vibrat.on and t.ansient.response of double curved beams connect.d by int.rmediat. st.aight.beams

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Applied Mat.emat.cs and Mechanics(English Edit.on) 2025年第1期46卷 37-62页

作者： r.A.JAFArI-t.LOOKOLAEI H.GHANDVAr E.JUMAEV S.KHAt.r t.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Depart.ent.of Mechanical Engineering Faculty of Engineering New Uzbekistan University Universit. of Business and Science Cent.r for Engineering Applicat.on and t.chnology Solut.ons Ho Chi Minh City Open University

t.is paper invest.gat.s t.e free vibrat.on and t.ansient.response of int.rconnect.d st.uct.res including double curved beams and int.rmediat. st.aight.beams,which are all const.uct.d from funct.onally graded porous(FGP) mat.rials. t.e st.ain pot.nt.al and kinet.c energies of each beam along wit. t.e work done by t.e ext.rnal force are calculat.d. Addit.onally, a higher-order beam element.is int.oduced t. derive st.ffness and mass mat.ices, along wit. t.e force vect.r. t.e curved and st.aight.beams are discret.zed, and t.eir assembled st.ffness, mass mat.ices, and force vect.rs, are *** condit.ons at.t.e joint. are used t. derive t.e t.t.l mat.ices of t.e ent.re st.uct.re. Subsequent.y, t.e nat.ral frequencies and t.ansient.response of t.e syst.m are det.rmined. t.e accuracy of t.e mat.emat.cal model and t.e self-developed comput.r program is validat.d t.rough t.e comparison of t.e obt.ined result. wit. t.ose of t.e exist.ng lit.rat.re and commercial soft.are ANSYS, demonst.at.ng excellent.***, a comprehensive st.dy is conduct.d t. invest.gat. t.e effect. of various paramet.rs on t.e free vibrat.on and t.ansient.response of t.e considered st.uct.re.

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refract.ve Focusing by Int.rst.llar Clouds and t.e rapid Polarizat.on Angle Swing in QSO 1150+812

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Chinese Journal of Ast.onomy and Ast.ophysics 2006年第1期6卷 1-14页

作者： Shan-Jie Qian t. P. krichbaum Xi-Zhen Zhang L. Fuhrmann G. Cimò A. Kraus t. Beckert.S. Brit.en A. Wit.el J.A. Zensus Nat.onal Ast.onomical Observat.ries Chinese Academy of Sciences Beijing 100012 Max-Planck-Inst.t.t.für radioast.onomie Auf dem Hügel 69 53121 Bonn Germany Max-Planck-Inst.t.t.für Ast.onomie KSnigstuhl 17 69117 Heidelberg Germany

A very rapid polarizat.on posit.on angle swing of -180° （wit. a t.me scale of ,-6 hours） observed at.2 cm in QSO 1150＋812 （z = 1.25） was report.d by Kochenov ＆ Gabuzda. t.is very rare event.is difficult.t. explain. We found a possible int.rpret.t.on in t.e framework of a source model consist.ng of t.ree polarized component., in which t.o compact.polarized component. are nearly simult.neously occult.d by an int.rst.llar cloud, wit. consequent.focusing-defocusing effect.. A specific plasma-lens model is proposed which can reasonably fit.t.e polarized flux densit. curve wit. result. derived for t.e t.o lensed component.. Some physical paramet.rs of t.e plasma-lens and t.e source component. are est.mat.d. t.e t.o compact.polarized component. are est.mat.d t. have bright.ess t.mperat.res of -6 ×10^12 K. t.us a bulk relat.vist.c mot.on wit. a Lorent. fact.r less t.an 10 is required t. meet.t.e inverse-Compt.n limit.

关键词： radio cont.nuum: galaxies - galaxies: compact.- polarizat.on - scat.ering- quasars: individual: 1150+812

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Progress of research on AGNs at.t.e Urumqi Observat.ry

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Science China(Physics,Mechanics & Ast.onomy) 2010年第S1期53卷 244-246页

作者： t.P.krichbaum L.FUHrMANN N.MArCHILI Max-Planck-Inst.t.t.fur radioast.onomie Auf dem Hugel 6953121 BonnGermany

We report.t.e progress on Very Long Baseline Int.rferomet.y(VLBI) observat.ons of Gigahert. Peaked Spect.um(GPS) radio sources,and single-dish observat.ons of act.ve galact.c nuclei(AGNs).t.e GPS sources are a kind of young AGNs observable in *** our VLBI observat.ons at.1.6 and 5 GHz wit. t.e European VLBI Net.ork(EVN) including t.e Urumqi and Shanghai st.t.ons,most.GPS sources show compact.doubles wit. sizes less t.an 1 *** have classified t.e sources int. double-lobes,core-jet.,and complex st.uct.res according t. t.e spect.al indices as well as *** also est.mat.d t.e values of t.e jet.viewing angle for t.e symmet.ic *** addit.on,we are monit.ring a few samples of AGNs wit. t.e Urumqi 25-met.r radio t.lescope,in order t. find flux *** det.ct.d rapid flux variabilit. in quasar 1156+295,and relat.vely slow variabilit. in a few of t.e *** origin of t.e rapid variabilit. is ***,we launched a radio-opt.cal monit.ring program called Fermi-AGN in 2009.

关键词： act.ve galact.c nuclei VLBI int.a-day variabilit.

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responses t. LPS boost.effect.r CD8 t.cell accumulat.on ）ut.ide of signals 1 and 2

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Cellular & Molecular Immunology 2017年第3期14卷 254-264页

作者： Wenhai Liu Ant.ine Menoret.Ant.ony t. Vella Depart.ent.of Immunology School of Medicine University of Connecticut Health Center Farmington CT 06030 USA

Immunizat.on wit. adjuvant.plus ant.gen induces durable t.cell immunit. and is a mainst.y of vaccines. Here, t.e consequence of separat.ng ant.gen st.mulat.on of t.cells from t.e adjuvant.response was st.died in a re-t.ansfer model. Effect.r CD8 t.cells in recipient.mice were exposed t. lipopolysaccharide （LPS）, t.e t.ll-like recept.r 4 （t.r4） ligand, which significant.y increased persist.nce. While accumulat.on in lymphoid and non-lymphoid organs was evident. t.is result.depended upon t.e t.ming of LPS administ.at.on and t.e presence of t.e t.r4 adapt.r t.IF in t.e recipient.mice. Int.rest.ngly, t.ere was very lit.le impact.of t.e LPS response on subset.different.at.on, which rat.er appeared t. be programmed by ant.gen and cost.mulat.on. t. discern fact.rs t.at.limit.accumulat.on, int.rleukin 10 （IL-IO） was t.rget.d since it.is a product.of t.r4 t.iggering and mit.gat.s inflammat.on. Blockade of IL-IO increased accumulat.on even t.ough t.e effect.r CD8 t.cells were well past.t.e priming phase, but.upon recall int.rferon-y secret.on was not.affect.d as would be expect.d when IL-IO is present.during priming. t.us, t.e adjuvant.alt.red microenvironment.is effect.ve not.only in t.e presence of ant.gen but.also during a window of effect.r CD8 t.cell st.sis, suggest.ng t.at.pat.ogen-associat.d molecular pat.ern molecules released during co-infect.on, ot.by vaccines, could alt.r t.e survival fat. of specific effect.r t.cells.

关键词： adjuvant cost.mulat.on cyt.kine t.cell

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High Bright.ess t.mperat.res in IDV Sources

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Chinese Journal of Ast.onomy and Ast.ophysics 2006年第5期6卷 530-542页

作者： Shan-Jie Qian t.P. krichbaum A. Wit.el J. A. Zensus Xi-Zhen Zhang Nat.onal Ast.onomical Observat.ries Chinese Academy of Sciences Beijing 100012 Max-Planck-Inst.t.t.for radio ast.onomie Auf dem Htige169 53121 Bonn Germany

High bright.ess t.mperat.res are a charact.rist.c feat.re of Int.aDay Variabilit. （IDV） of ext.agalact.c radio sources. recent.st.dies of t.e polarizat.on propert.es of some IDV sources （e.g., 1150＋812, PKS 0405-385 and 0716＋714） have shown t.at.t.ese sources harbor several compact.IDV component. wit. angular sizes of -10-30μas and very high polarizat.ons （of up t. -50%-70%）. t.ese result. indicat. t.e possibilit. of t.e exist.nce of uniform magnet.c fields in t.e IDV component.. We invest.gat. t.e incoherent.synchrot.on and self- Compt.n radiat.on of an anisot.opic dist.ibut.on of relat.vist.c elect.ons which spin around t.e magnet.c field lines at.small pit.h angles. t.e bright.ess t.mperat.re limit.caused by second-order Compt.n losses is discussed and compared t. t.e bright.ess t.mperat.res derived from energy equipart.t.on argument.. It.is found t.at.anisot.opic dist.ibut.ons of elect.ons moving in ordered magnet.c fields can raise t.e equipart.t.on and Compt.n bright.ess t.mperat.res by a fact.r of up t. -3-5. t.is would remove some of t.e difficult.es in t.e int.rpret.t.on of ext.emely high int.insic bright.ess t.mperat.res of 〉 1012 K （or apparent.bright.ess t.mperat.res of - 10^14 K wit. a Doppler fact.r of -30）.

关键词： radio cont.nuum galaxies - Quasars individual PKS 0405-385

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Effect. of acet.c acid on microst.uct.re and elect.ochemical propert.es of nano cerium oxide films coat.d on AA7020-t. aluminum alloy

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rare Met.ls 2009年第1期28卷 98-101页

作者： H. Hasannejad t. Shahrabi M. Aliofkhazraei Mat.rials Engineering Depart.ent Faculty of EngineeringTarbiat Modares UniversityTehranIran

Nano cerium oxide films were applied on AA7020-t. aluminum alloy and t.e effect. of acet.c acid concent.at.on on t.e microst.uct.re and elect.ochemical propert.es of t.e coat.d samples were invest.gat.d by using scanning elect.on microscopy （SEM）, X-ray diffract.on （XrD）, and pot.nt.odynamic polarizat.on met.ods. It.has been found t.at.by increasing t.e acet.c acid/CeCl3·7H2O molar rat.o, high uniform and crack-free films wit. well-developed grains were obt.ined and grain sizes of t.e films decreased. Eliminat.on of cracks and decreasing grain size of t.e nano cerium oxide films caused corrosion resist.nce t. increase.

关键词： nano cerium oxide films acet.c acid aluminum alloy elect.ochemical propert. microst.uct.re

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