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A new th.ee-stage evolution mod.l for millimeter to centimeter wavelength.outbursts in BL Lacertae

Research.in Astronomy and.Astroph.sics 2010年第1期10卷 47-66页

作者： Sh.n-Jie Qian T. P. Krich.aum A. Witzel J. A. Zensus Xi-Zh.n Zh.ng h. Ungerech.s h. d. aller M. E aller National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Max-Planck-Institut fur Rad.oastronomie Auf dem Hugel 69 Bonn 53121 Germany Instituto Rad.oastronomia Milimetrica （IRAM） Avenida Divina Pastora 7 Nficleo Central E-18012 Granada Spain d.partment of Astronomy University of Michigan Ann Arbor M148109-1042 USA

Th. multi-frequency ligh. curves of BL Lacertae d.ring 1997.5 - 1999.5 h.ve been mod.led.by four outbursts, each.h.ving a 3-stage evolution in th. （Sm, vm） plane with.d.stinct rising-plateau-d.caying ph.ses. It is sh.wn th.t th. observed.ligh. curves can be well fitted.for th. eigh. frequencies from 350 Gh. to 4.8 Gh.. Th. main ch.racteristics of th. mod.l-fitting are; （1） th. outbursts are found.to h.ve very flat spectra with.an optically th.n spectral ind.x α （d.fined.as Sv α u^-α） of about 0.15. Th.s is consistent with.th. results previously obtained.by Valtaoja et al. （1992）; （2） it is found.th.t th.re is no spectral flattening between th. rising-plateau ph.se and.th. d.cay ph.se. In oth.r word., th. optically th.n spectral ind.x d.es not ch.nge from th. rising-plateau ph.se to th. d.cay ph.se. Th.se features are in contrast to th. 3-stage sh.cked.in-jet mod.l proposed.by Marsch.r ＆ Gear （1985） for submm- IR-optical flares, in wh.ch.a spectral flattening of △α = 0.5 is pred.cted.wh.n a transition occurs from th. Compton/synch.otron ph.se （or rising-plateau ph.se） to th. ad.abatic ph.se （or d.cay ph.se） with.α≥ 0.5 for th. sh.ck being non-rad.ative. We propose a new mod.l to interpret th. fitting results, suggesting th.t th. 3-stage evolution of th. mm-cm outbursts in BL Lacertae may be related.to th. process of sh.ck formation and.propagation in a h.gh.y collimated.jet （for example, a ＇parabolic＇ jet）. In particular, d.ring th. rising ph.se, th. th.ckness of th. synch.otron-rad.ating region created.by th. sh.ck may rapid.y increase with.time （relative to th. jet wid.h. d.e to th. rapid.injection of relativistic electrons and.a magnetic field. and.th.s lead. to th. observed.beh.vior th.t th. turnover flux d.nsity Sm rapid.y increases wh.le th. turnover frequency um d.creases. In th. d.cay ph.se, th. emitting plasma enters into a free expansion regime with.ut furth.r injection of relativistic electrons and.a magnetic field.（for example, wh.n a transition from a co

关键词： rad.o continuum galaxies - rad.o outburst - quasars ind.vid.al BL Lacertae

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A Possible Period.city in th. Rad.o Ligh. Curves of 3C 454.3

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Ch.nese Journal of Astronomy and.Astroph.sics 2007年第3期7卷 364-374页

作者： Sh.n-Jie Qian N. A. Kud.yavtseva S. Britzen T. E Krich.aum Long Gao A. Witzel J. A. Zensus M. E aller h. d. aller Xi-Zh.n Zh.ng National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Max-Planck-institut ftir Rad.oastronomie Auf dem HUgel 69 53121 Bonn Germany Astronomy d.partment University of Michigan Ann Arbor MI 48109 USA Astronomical Institute of St.-Petersberg State University Petrodvoretz St.-Petersburg Russia International Max-Planck Research.Sch.ol for Rad.o and.Infrared.Astronomy at th. Universities of Bonn and.Cologne

d.ring th. period.1966.5-2006.2 th. 15 Gh. and.8 Gh. ligh. curves of 3C 454.3 （z = 0.859） sh.w a quasi-period.city of ,-12.8 yr （-6.9 yr in th. rest frame of th. source） with.a d.uble-bump structure. Th.s period.c beh.viour is interpreted.in terms of a rotating d.uble-jet mod.l in wh.ch.th. two jets are created.from th. black h.les of a binary system and.rotating with.th. period.of th. orbital motion. Th. period.c variations in th. rad.o fluxes of 3C 454.3 are suggested.to be mainly d.e to th. ligh.h.use effects （or th. variation in d.ppler boosting） of th. precessing jets caused.by th. orbital motion. In ad.ition, variations in th. rate of mass accreting onto th. black h.les may be also involved.

关键词： rad.o continuum galaxies - Quasars ind.vid.al 3C 454.3

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A Math.matical Mod.l for th. h.at Rad.ation Ch.racteristics of Materials

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Journal of Th.rmal Science 2004年第1期13卷 75-79页

作者： d. h. Xia Y. h. Wu Univ Sci & Tech.ol Beijing Dept Thermal Engn Beijing 100083 Peoples R China

Based.on th. mod.l of h.rmonic oscillators, a math.matical mod.l for th. h.at rad.ation ch.racteristics of materials such.as semicond.ctors, metals, plasmas and.ionic crystals is establish.d.in th.s paper. Th. main factors affecting th. h.at rad.ation ch.racteristics of materials are also analyzed.at length. Th. emissivity is calculated.for revealing th. mech.nism of emitting, absorbing, transmitting and.reflecting th. h.at rad.ation wave.

关键词： h.rmonic oscillator math.matical Mod.l h.at rad.ation wave emissivity.

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Impact of wind.power generating system integration on frequency stabilization in multi-area power system with.fuzzy logic controller in d.regulated.environment

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Frontiers in Energy 2015年第1期9卷 7-21页

作者： Y. K. Bh.TESh.AR h. d. MATh.R h. SIGUERd.d.ANE d.partment of Electrical and.Electronics Engineering Birla Institute ofTechnology and Science Pilani Rajasthan 333031 India Automatic Control d.partment Sup61ec Gif-sur-Yvette 91192 France

Among th. available options for renewable energy integration in existing power system, wind.power is being consid.red.as one of th. suited.options for future electrical power generation. Th. major constraint of wind.power generating system （WPGS） is th.t it d.es not provid. inertial support because of power electronic converters between th. grid.and.th. WPGS to facilitate frequency stabilization. Th. proposed.control strategy suggests a substantial contribution to system inertia in terms of sh.rt-term active power support in a two area restructured.power system. Th. control sch.me uses fuzzy logic based.d.sign and.takes frequency d.viation as input to provid. quick active power support, wh.ch.balances th. d.op in frequency and.tie-line power d.ring transient cond.tions. Th.s paper presents a compreh.nsive stud. of th. wind.power impact with.increasing wind.power penetration on frequency stabilization in restructured.power system scenario. Variation of load.cond.tions are also analyzed.in simulation stud.es for th. same power system mod.l with.th. proposed.control sch.me. Simula- tion results ad.ocates th. justification of control sch.me over oth.r sch.mes.

关键词： two area power system automatic generationcontrol wind.power generating system (WPGS) d.regu-lated.environment fuzzy logic controller (FLC)

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Interaction between B-d.ped.C60 Fullerene and.Glycine Amino Acid.from First-Principles Simulation

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Ch.nese Ph.sics Letters 2010年第4期27卷 83-86页

作者： M. d. Ganji h. Yazd.ni d.partment of Ch.mistry Islamic Azad University Ghaemshahr branch Mazandaran Iran

Th. possibility of formation of complexes between glycine and.boron d.ped.C60 （C59B） fullerene is investigated.and.compared.with.th.t of C60 fullerene by using th. d.nsity functional th.ory calculations. It h.s been found.th.t th. bind.ng of glycine to C59B generated.th. most stable complexes via its carbonyl oxygen active site, with.a bind.ng energy of-37.89 kcal/mol, wh.le th. glycine molecule prefers to bind.to th. pure C60 cage via its amino nitrogen active site, consistent with.th. recent experimental and.th.oretical stud.es. We h.ve also tested.th. stability of th. most stable Gly-C59B complex with.ab initio molecular d.namics simulation, carried.out at room temperature. Th.se ind.cate th.t th. B-d.ped.C60 fullerenes seem to be more suitable materials for bind.ngs to proteins th.n pure C60 fullerenes.

关键词： Surfaces interfaces and.th.n films Biological ph.sics Cond.nsed.matter: structural mech.nical & th.rmal Ch.mical ph.sics and.ph.sical ch.mistry

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Microbial d.sulfurization of fuel oil

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Ch.nese Science Bulletin 2002年第5期47卷 365-369页

作者： h. d. Blankespoor Biology d.partment of h.pe College Holland

Culture cond.tions of d.sulfurization microbes were investigated.with.a bioreactor controlled.by computer. Factors such.as ph. ch.ice of carbon source, optimal concentrations of carbon, nitrogen and.sulfur sources were d.termined. Th. ad.ition of carbon in a culture with.a constant ph.greatly improved.th. growth.of Rh.d.coccus. Cells and.cell d.bris from microbes rested.using a sulfur-specific path.ay were used.to d.sulfurize d.esel oil treated.by h.-d.od.sulfurization (acquired.from th. Research.Institute of Fush.n Petroleum with.total sulfur level at 205μg/mL). Strains lawq, IG, X7B, ZT, ZCR, and.a mixture of No. 5 and.No. 6, were used.in th. biod.sulfurization process. Th. red.ction of total sulfur was between 10.6% and.90.3%.

关键词： d.benzoth.oph.ne (d.T) biod.sulfurization (Bd.) h.-d.od.sulfurization (h.S) fuel oil.

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LIVING/CONTROLLEd.GRAFTING FROM POLYMER MICROSPh.RES

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Ch.nese Journal of Polymer Science 2003年第6期21卷 639-651页

作者： h.rald.d. h. Stver d.pt. of Ch.mistry McMaster University Hamilton ON L8S 4MI Canada

A review is given of grafting-from meth.d. using living polymerizations, with.emph.sis on grafting from polymermicrosph.res using ATRP.

关键词： Living controlled.polymerization Grafting ATRP Microsph.res

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A continuum traffic flow mod.l with.th. consid.ration of coupling effect for two-lane freeways

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Acta Mech.nica Sinica 2011年第2期27卷 228-236页

作者： d.-h. Sun G.-h. Peng L.-P. Fu h.-P. h. College of Automation Chongqing University400030 Chongqing China d.partment of Civil & Environmental Engineering University of Waterloo Waterloo Ontario N2L 3G 1 Canada College of Automation Chongqing University 400030 Chongqing China

A new h.gh.r-ord.r continuum mod.l is proposed.by consid.ring th. coupling and.lane ch.nging effects of th. veh.cles on two ad.acent lanes. A stability analysis of th. proposed.mod.l provid.s th. cond.tions th.t ensure its linear stability. Issues related.to lane ch.nging, sh.ck waves and.rarefaction waves, local clustering and.ph.se transition are also investigated.with.numerical experiments. Th. simulation results sh.w th.t th. proposed.mod.l is capable of provid.ng explanations to some particular traffic ph.nomena commonly observable in real traffic flows.

关键词： Two-lane traffic Two d.lay time scales mod.l Numerical simulation Coupling effect Ph.se transition

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Experimental investigation of tool wear and.ch.p formation in cryogenic mach.ning of titanium alloys

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Ad.ances in Manufacturing 2015年第4期3卷 292-299页

作者： d. Biermann h. Abrah.ms M. Metzger Institute of Mach.ning Tech.ology TU Dortmund University Baroper StraBe 303 44227 Dortmund Germany

Titanium alloys are one of th. most important d.sign materials for th. aircraft ind.stry. Th. h.gh.strength.to-d.nsity-ratio and.th. compatibility with.carbon fibre reinforced.plastic are th. reasons for a raising application in th.s field. Th. outstand.ng properties lead.to ch.llenging mach.ning processes. h.gh.strength.and.low h.at cond.ctivity affect h.gh.mech.nical and.th.rmal load. for th. cutting ed.e. Th.s, th. mach.ning process is ch.racterized.by a rapid.d.velopment of tool wear even at low cutting parameter. To reach.a sufficient prod.ctivity it is necessary to d.ssipate th. resulting h.at from th. cutting ed.e by a coolant. Th.refore th. cryogenic mach.ning of two d.fferent titanium alloys is investigated.in th.s work. Th. results point out th. d.fferent beh.vior of th. mach.ning processes und.r cryogenic cond.tions because of th. red.ced.th.rmal load.for th. cutting tool. Accord.ng to th.s investigation, th. cryogenic cooling with.COa enables an increase of th. tool life in comparison to emulsion based.cooling principles wh.n mach.ning th. α＋β-titanium alloy Ti-6Al-4V. Th. mach.ning process of th. h.gh.strength.titanium alloy Ti-6Al-2Sn-4Zr-6Mo requires an ad.itional lubrication realized.by a minimum quantity lubrication （MQL） with.oil. Th.s combined.cool- ing lead. to a smooth.r ch.p und.rsid. and.to slend.r sh.ar band. between th. d.fferent ch.p segments.

关键词： Titanium alloys . Cryogenic cooling Mach.ning . Tool wear - Ch.p formation

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Investigations on th. Corrosion Beh.viour and.Structural Ch.racteristics of Low Temperature Nitrid.d.and.Carburised.Austenitic Stainless Steel

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材料热处理学报 2004年第5期25卷 311-315页

作者： d. Mnter h.-J. Spies h. Biermann Ch.. Eckstein d.partment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyCorrosion laboratory Steel-Centre-Freiberg (SZF) Research centre of the Technische Universitat Bergakademie Freiberg 09599 Freiberg/ Germany

Th. wear resistance of austenitic stainless steels can be improved.by th.rmo-ch.mical surface treatment with.nitrogen and.carbon. h.wever, it is possible th.t th. corrosion resistance will be impaired.by th. precipitation of ch.omiumnitrid.or -carbid.. Th. present contribution d.als with.investigations of th. corrosion beh.viour and.structural ch.racteristics of a low temperature nitrid.d.and.carburised.austenitic stainless steel. Th. material investigated.was AISI 316L (X2CrNiMol7-12-2) austenitic stainless steel. A commercial plasma-nitrid.ng unit (pulsed.d.) was used.for th. nitrid.ng and.carburising process. Ad.itional samples were treated.by th. gasoxinitrid.ng process for a comparison between plasma- and.gasoxinitrid.ng. Th. nitrid.d.and.carburised.layer of austenitic stainless steel consists of th. nitrogen or carbon S-ph.se (expand.d.austenite), respectively. X-ray d.ffraction investigations sh.w th. typical sh.ft of th. peaks to lower angles, ind.cating expansion of th. fee lattice. Also th. X-ray d.ffraction tech.ique was employed.to stud. th. resid.al stresses in th. nitrogen and.carbon S-ph.se. Th. corrosion beh.viour of surface engineered.samples was investigated.with.electroch.mical meth.d.. Anod.c potentiod.namic polarisation curves were record.d.for testing th. resistance against general corrosion (in h.SO4) and.pitting corrosion (in NaCl).

关键词：奥氏体不锈钢腐蚀低温渗氮低温渗碳残留应力

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