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简介：2006年8月，“ICPE2006国际物理教育大会”在日本东京召开，东南大学恽瑛教授在会议上作题为《通过双语物理教学培养大学一年级学生的创新能力》的报告，恽瑛教授带领的2005级本科生李鑫、杜源、胡特、姜坤也分别作了口头报告和张贴报告。他们在会议上的精彩发言与会议期间的表现，引起了与会代表和著名的《Science》杂志的极大兴趣。

简介：送检地下水水型为HCO3^--SO4^2--Ca^2＋-（Mg^2＋）型，酸碱度为中性、水介质属氧化型（Eh=640my）、低矿化，样品水中各项水质分析项目为，K^＋＋Na^＋，Ca^2＋，Mg^2＋，Fe^3＋，Cl^-，SO4^2-，HCO3^-，CO3^2-，NO3^-，OH^-；所对应分析值为0．670×10^-3，1．200×10^-3，0．400×10^-3，1．79×10^-3，0．036×10^-3，0．88×10^-3，2．074×10^-3，10^-5.863，0．035×10^-3，10^-7.07。

简介：为了明确团聚现象及表面性质对ZnS纳米材料发光性质的影响，采用SiO2对ZnS材料进行了表面修饰，并对ZnS及ZnS／SiO2复合材料的光学性质进行对比研究。采用吸收光谱分析了包覆前后光吸收性质的差异，发现SiO2包覆后ZnS纳米材料的带边由333nm红移至360nm。为了研究ZnS纳米材料与ZnS／SiO2纳米复合材料的光发射性质，分别对含纳米材料的水溶液样品及粉末样品的发光光谱进行了采集。对比研究的结果表明，SiO2包覆后ZnS纳米材料在蓝紫光区的发光得到了明显增强。以氙灯作为激发光源所获得荧光光谱显示ZnS／SiO2粉末样品发光的积分强度增大为原来的17．5倍，但相同条件下针对溶液样品的测试结果显示其发光强度只增大了1．1倍，这种增强可用SiO2的存在抑制了ZnS纳米粒子间的团聚来解释，且这一推断由325nm紫外激光激发下获得的光致发光数据进行了验证。

简介：Variousagriculturalcropresiduesincludingcornstover,corncob,andsorghumstalkwithamoisturecontentof75wt%weresubjectedtoalongpretreatment(12-60h)withsupercriticalCO2(scCO2),atlowtemperature(50-80℃)andapressureof17.5-25.0Mpa.Thesugaryieldsfromtheenzymatichydrolysis(EH)ofthepretreatedsampleswereasmuchasthree-tofourfoldgreaterthanthoseaffordedbytherawmaterials.However,whenpretreatmentwasconductedwithinashorttime(e.g.0.5h),aspreviouslyreportedintheliterature,onlyaslightincreaseintheEHsugaryieldswasobserved.TheproposedscCO2pretreatmentmechanismdemonstratedtheroleofmoistureinthesystem.Wetting,softening,andswellingwereobservedtomainlyaffectthelignocellulosewhenasuitableamountofwaterwasadded.Finally,thesampleswereanalysedbyX-raydiffractionandscanningelectronmicroscopy,beforeandafterpretreatment,toinvestigatethechangesinthemicroscopicstructureofthebiomass.

简介：Ｒｏｔａｔｉｏｎ　ｉｎ　Ｒｅａｃｔｉｏｎ　１９Ｆ＋５１ＶＲｏｔａｔｉｏｎｉｎＲｅａｃｔｉｏｎ１９Ｆ＋５１Ｖ￥ＷａｎｇＱｉ；ＬｕＪｕｎ；ＸｕＨｕｓｈａｎ；ＬｉＳｏｎｇｌｉｎ；ＺｈｕＹｏｎｇｔａｉａｎｄＺｈａｎｇＹｕｈｕＩｎｄＬｓｓｉ...

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简介：为验证CO_2探测仪光学设计的合理性和可行性，采用单通道模拟样机，利用太阳光加漫反射板模式对大气光谱进行实验测试，并在实验室对单通道模拟样机进行光谱定标。利用光谱配准算法对两种方法得出的谱线位置进行匹配计算，结果表明：在吸收线深度稳定位置的配准峰值点偏差小于0．006nm，满足算法的精度要求。此种方法不仅验证了匹配算法的有效性，也验证了光学系统设计的合理性和可行性，为以后的光谱仪设计提供了理论与实验数据。

简介：Anovelgas-phaseelectrocatalyticcellcontainingalow-temperatureprotonexchangemembrane(PEM)wasdevelopedtoelectrochemicallyconvertCO2intoorganiccompounds.TwodifferentCu-basedcathodecatalysts(CuandCu-C)werepreparedbyphysicalvapordepositionmethod(sputtering)andsubsequentlyemployedforthegas-phaseelectroreductionofCO2atdifferenttemperatures(70-90℃).ThepreparedelectrodesCuandCu-CwerecharacterizedbyX-raydiffraction(XRD),X-rayphotoemissionspectroscopy(XPS)andscanningelectronmicroscopy(SEM).Asrevealed,CuispartiallyoxidizedonthesurfaceofthesamplesandtheCuandCu-Ccathodiccatalystswerecomprisedofaporous,continuous,andhomogeneousfilmwithnanocrystallineCuwithagrainsizeof16and8nm,respectively.Theinfluenceoftheappliedcurrentandtemperatureontheelectro-catalyticactivityandselectivityofthesematerialswasinvestigated.Amongthetwoinvestigatedelectrodes,thepureCucatalystfilmshowedthehighestCO2specificelectrocatalyticreductionratesandhigherselectivitytomethanolformationcomparedtotheCu-Celectrode,whichwasattributedtothehigherparticlesizeoftheformerandlowerCuO/Curatio.Theobtainedresultsshowpotentialinterestforthepossibleuseofelectrical「enewableenergyforthetransformationofCO2intovaluableproductsusinglowmetalloadingCubasedelectrodes(0.5mgCucm2)preparedbysputtering.

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简介：Inthiswork,MoOxpromotedIr/SiO2catalystswerepreparedandusedfortheselectivehydrogenolysisoftetrahydrofurfurylalcohol(THFA)to1,5-pentanediolinacontinuousflowreactor.Theeffectsofdifferentnoblemetals(Ir,Pt,Pd,Ru,Rh),supportsandIrcontentswerescreened.Amongtheinvestigatedcatalysts,4wt%Ir-MoOx/SiO2withaMo/Iratomicratioof0.13exhibitedthebestcatalyticperformance.ThesynergybetweenIrparticlesandthepartiallyreducedisolatedMoOxspeciesattachedonthemisessentialfortheexcellentcatalyticperformanceofIr-MoOx/SiO2.ThecatalystexhibitedabetterhydrogenolysisefficiencyofTHFAwiththeselectivityof1,5-pentanediolof65%–74%ataconversionofTHFAof70%–75%whentheinitialTHFAconcentrationisrangingfrom20wt%and40wt%.AndhighersystempressurewasalsoinfavoroftheconversionofTHFA.Duringastabilitytest,theconversionofTHFAand1,5-pentanediolyieldoverIr-MoOx/SiO2decreasedwithreactiontime,whichcanbeexplainedbytheleachingofMospeciesduringthereaction.

简介：留声机诞生于1877年．世界上第一个发明留声机的人就是誉满全球的发明大王——爱迪生．当时爱迪生发明的留声机轰动了整个纽约，各家报馆的新闻记者，像潮水般地涌来报道这一特大新闻．“一台会说话的机器”“一台会收藏声音的机器”，激起当时社会急速而巨大的狂热，外界舆论把留声机称之为19世纪的奇迹，即将开幕的巴黎世界博览会立即把它作为时新展品展出，就连当时美国总统海斯也在留声机旁转了两个多小时．

简介：Catalyticpropertiesofthemetal-organicframeworkCr-MIL-101insolvent-freecycloadditionofCO2toepoxidestoproducecycliccarbonatesusingtetrabutylammoniumbromideasco-catalysthavebeenexploredundermildreactionconditions(8barCO2,25C).Styreneandpropylenecarbonateswereformedwithhighyields(95%and82%,respectively).CatalyticperformanceofCr-MIL-101wascomparedwithotherMOFs:Fe-MIL-101,Zn-MOF-5andHKUST-1.Thecatalyticpropertiesofdifferentquaternaryammoniumbromides,Cr-MIL-101aswellasPW12/Cr-MIL-101compositematerialhavebeenassessedinoxidativecarboxylationofstyreneinthepresenceofbothtert-butylhydroperoxideandH2O2asoxidantsat8100barCO2and2580Cwithselectivitytostyrenecarbonateupto44%at57%substrateconversion.

简介：合成了六铝酸盐ＳｒＮｉＡｌ１１Ｏ１９并用ＸＲＤ、ＵＶＤＲＳ、ＴＧＤＴＡ和ＴＥＭ等技术对其进行了表征。在７５０℃于ＳｒＮｉＡｌ１１Ｏ１９上进行的甲烷与二氧化碳重整反应表明，这类催化剂较Ｎｉ／ＳｒＡｌ１２Ｏ１９具有较大活性和低积碳能力，在催化反应过程中可有效地抑制Ｎｉ颗粒的增大。

简介：Thebaryonspectrumandthebaryoncouplingsaretwoofthemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.Bothontheexperimentalandtheoreticalsides,thenucleonexcitedstatesbelow2.0GeVhavebeenextensivelystudied[1].However,thecurrentinformationforthepropertiesofstatesaroundorabove2.0GeVisscarce.Ontheotherhand,inthisenergyregion,manytheoreticalapproacheshavepredictedmissingNstates,whichhavenotbeensofarobserved.Hence,thestudyofthepossibleroleplayedbythe2.0GeVregionnucleonresonancesintheavailableaccuratedataistimelyandcouldshedlightintothecomplicateddynamicsthatgovernsthehighexcitednucleonspectrum.

简介：LECR4isthefirstECRionsourceusingevaporativecoolingtechnologyintheworld.Itsuniquefeatureisthatthesolenoidsweremadefromsolidsquarecopperwires(3.32mm×5.77mmwithinsulation),andthatallthecoilsareentirelyimmersedintheroomtemperaturecoolant.Thecoilscanproduceamaximumaxialmagneticfieldupto2.5T.LECR4aimstoprovideintensemultiplechargestateionbeamsforSSC-Linacproject-anewLinearinjectorfortheSeparatedSectorCyclotron(SSC).Presently,someionbeamswithdifferentM/QratiohavebeenacceleratedsuccessfullywiththeRFQandDTL,suchas200eμAof16O^5+,200eμAof40Ar^8+,50eμAof209Bi^30+etc.ThemeasuredtransmissionefficiencyofRFQisupto90%.ThelayoutofLECR4ionsourceandtheLEBTisshowninFig.1.

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