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简介：这属奥林匹克竞赛在芬兰的赫尔辛基举行。每个国家派5名学生参加。这届的规模出以往各届都大，共有来自37个国家的178名参赛者，而我也能够成为这次盛大竞赛的参加者之一！

简介：2011年全国初中应用物理知识竞赛已落下帷幕，掩卷沉思，切实感受到试题具有贴近生活实际、突出物理知识应用、重视学生动手能力和科学探究的特点，有利于提高学生的科学素养，培养创新精神．

简介：Supernova(SN)neutrinosdetectedontheEartharesubjecttotheshockwaveeffects,theMikheyev–Smirnov–Wolfenstein(MSW)effects,theneutrinocollectiveeffectsandtheEarthmattereffects.Consideringtherecentexperimentalresultaboutthelargemixingangleθ13(■8.8°)providedbytheDayaBayCollaborationandapplyingtheavailableknowledgefortheneutrinoconversionprobabilityinthehighresonanceregionofSN,PH,whichisintheformofhypergeometricfunctioninthecaseoflargeθ13,wededucetheexpressionofPHtakingintoaccounttheshockwaveeffects.ItisfoundthatPHisnotzeroinacertainrangeoftimeduetotheshockwaveeffects.Afterconsideringallthefourphysicaleffectsandscanningrelevantparameters,wecalculatetheeventnumbersofSNneutrinosforthe"Garching"distributionofneutrinoenergyspectrum.Fromthenumericalresults,itisfoundthatthebehaviorsofneutrinoeventnumbersdetectedontheEarthdependontheneutrinomasshierarchyandneutrinospectrumparametersincludingthedimensionlesspinchingparameterβα(whereαreferstoneutrinoflavor),theaverageenergy,andtheSNneutrinoluminositiesLα.Finally,wegivetherangesofSNneutrinoeventnumbersthatwillbedetectedattheDayaBayexperiment.

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简介：IntheBigBangtheory,primordialnucleosynthesiswasfinishedduringfirsthalfhouroftheuniverse’sexistence.Thisprocessyieldedthemainlightelementsincludinghydrogen,deuterium,heliumandlithium.Thetheoreticalpredictionsmatchverywelltheobserveddeuteriumandheliumabundance,butthe7Liabundanceisoverpredictedbyafactorathree[1].Thisinconsistencyiscalled“cosmologicallithiumproblem”.Inthepastdecade,manyattemptstosolvethisproblemusingconventionalastrophysicsandnuclearphysicsfailed.Recently,weproposedanewsolutiontolithiumproblembyintroducingnon-extensivestatisticsintoBigBangnucleosynthesis[2].

简介：近年来,太赫兹科学技术的研究已成为国内外学术界最热门领域之一,发展十分迅猛,研究成果引起了广泛关注,在全世界范围掀起了太赫兹科学研究的热潮。国际红外毫米波-太赫兹会议是本领域内最权威、水平最高、历史最悠久的会议,体现该领域发展的最前沿方向。随着太赫兹科学技术的飞速发展,该会议不断向着太赫兹领域倾斜,2013年第38届国际红外毫米波-太赫兹会议重心已全面转向太赫兹领域,全方位展现了当今国际太赫兹科学技术研究进展。本次会议也引起了国际学术界高度重视,＂NaturePhotonics＂在此次会议召开后1个月内即发表以太赫兹为主题的焦点期刊（＂FocusIssue＂）,对太赫兹领域研究进展进行报道。

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简介：Multi-nucleontransferreactionplaysanimportantroleinthesynthesisofnewnuclides[1].Inthereactionsof20Ne+209Bi,someshort-livednucleiproducedbytransferring26nucleonswerediscovered.Theexperimentof20Ne+209Biwasperformedatgas-filledrecoilseparatorinLanzhou[2].A400g/cm2thick209Bitargetwasbombardedwith20NebeamdeliveredbyacceleratorHIRFL.

简介：TheCADSdemofacilityisaimedtobuildaprototypelinacforthelowenergypartofthecontinuouswave(CW)superconductingprotonlinacanddemonstratetechnologyinthissection[1].IntheCADSroadmap,therealizationof25MeV10mAbeamisakeypoint.Thus,basedonthe10MeVCADSInjectorIIatIMP,IMPandIHEPwillbothcontributeacryomoduletoreach25MeVatthesiteofIMP[2].Todumpthebeamfromthelinac,webuildanewhighenergybeamtransportlinewithbendingangleof90°,toavoidback-scatteringgammaandneutronbeamstodamagethelinac.Fig.1showsthelayoutofthe25MeVdemofacility.

简介：ThepresolarSiCgrains[1]carrytheoriginalstellarnucleosynthesissignature.Theirisotopicanomaliescomparedtothesunarethestrongconstrainsinthesupernovae(SN)modelcalculations.The15N-excessinsomeSiC-ABgrains(12C/13C<10and14N/15N<272)isoneofthechallengesofcore-collapsesupernovae(CCSNe)models[2].Recently,PignataripointedoutthattheentrainmentofH-richmaterialintotheHeshellbeforetheSNexplosionallowsthecoproductionof13C,15Nand26Al,whichprovidesanewproductionscenarioforSiC-ABgrains[2].IntheHeshellnucleosynthesis,the13Cisproducedthrough12C(p,γ)13N(β+γ)13Creaction.The14Nissynthesizedthrough13N(n,γ)and13C(p,γ)reactions.

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简介：一、填空题（每空1分，共25分）1．实验室里常用__________等仪器测物体的质量．若宇航员将一质量为2kg的矿石样本从月球带到地球上，它的质量是__________kg，物重是_______N．

简介：第9路已基本建成并投入试运行，现能输出脉宽2ns，能量1．5kJ的倍频激光，开始用作X光背光驱动源。

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简介：怎样既廉价又方便地获得电能，是19世纪科学家们认真研究并亟待解决的课题．1820年，丹麦科学家奥斯特成功地实现了“电生磁”的实验，即发现了通电导线能使磁针发生偏转．在此基础上，当时不少科学家进一步研究，并由实验得出了这样的结论：磁针之所以会发生偏转，是因为受到了力的作用，这种力来自于电荷流动的电力．

简介：近来，老师们就物理中考第12题展开了热烈的讨论，这是一种很好的现象．每个人都会有自己的看法，可以说“仁者见仁，智者见智”，目的在于提高认识，使物理教学在健康的道路上发展．

简介：The12C+13Csystemhasbeenstudiedextensively,becauseofthesimilarityoftheentrancechanneltotheastrophysicallyimportant12C+12Creaction[1??3].Untilnow,threedifferentmethodshavebeenexploitedtoperformthefusioncrosssectionmeasurementsfor12C+13CundertheCoulombbarrier:(1)measuringtheyieldofcharacteristicrays,(2)thetotal-rayyieldsusingNaIsummingdetectorsand(3)theactivityofthereactionresidue24Na(T1=2=15.0h).Recently,thefusioncrosssectionof12C+13Chasbeenmeasureddownto0.9nbthroughtheactivitymeasurementbyourgroup[4].Althoughthestatisticalmodelcalculationsinallthesethreemethodshavebeenroutinelyusedtoconverttheobservedpartialcrosssectionsintothetotalfusioncrosssections[5],thesystematicuncertaintyinducedbythestatisticalcorrectionshasnotbeenstudiedverywell.