简介：Anovelpre-ionizationschemeofhelicaltransverse-pulsedpre-ionizationinalongitudinaldischargeCO2laserispresented.Thelasertubeismadeofglasswithinnerdiameterof7.5mmanddischargelengthof50cm.Thelaserperformancecharacteristicsasfunctionsofparameters,suchaspressure,chargingcapacitanceandappliedvoltage,areinvestigated.Comparedwiththesamelaserstructurewithoutpre-ionization,themaximumpulseenergyimprovesby23%,theoptimumelectro-opticalefficiencyincreasesby31%,andthespecificoutputenergyreaches26J/(L·atm).

简介：Inthispaper,quartzcrystalmicrobalance(QCM)gassensorscoatedwithpolyehtyleneimine(PEI)wasutilizedforcarbondioxide(CO2)detection.Thesensingmechanismisbasedontheavailabilityofreversibleacid-basereactionsbetweenCO2moleculesandPEIatroomtemperature.TheexperimentalresultsrevealedthatthePEI/starchsensorexhibitedmuchhighersensitivitythanthatofpurePEI,andshowedapproximatelinearityoveraconcentrationregionrangingfrom500ppmto8000ppm.Theinfluenceofhumidityhadalsobeeninvestigated.Furthermore,theresponseandrecoverytimedeceasedastheoperationtemperaturesincreased.Finally,sensitivitylossafterconservationforseveraldaysandreversibilityofthesensorshadbeendiscussed.

简介：人类已经清楚地认识到,自身在生产生活中排出的化学物质的数量远远超出了地球自身的净化能力,人类的生存环境被严重破坏,人类文明遇到了严峻的挑战。这就要求清洗行业的从业人员在选择清洗剂时,不仅要考虑清洗能力,还要考虑安全环保性,防止清洗剂损害操作人员的健康,尽量降低对环境的污染。

简介：本文根据使用经验对溶剂清洗设备的安全、环保等方面存在的缺欠提出了可行的改进方案,使溶剂清洗设备的结构趋于完善,并提供了安全、环保等方面的保障,既保护了操作人员的身体健康,又避免了对环境的破坏.

简介：本文论述影响超声清洗设备清洗溶剂的挥发浓的因素，并提出降低清洗溶剂的挥发浓度一些方法。

简介：我国目前的溶剂油生产,绝大多数是呆用简单的精馏方法,原料采用炼油厂的直馏分油技术,硫、氮含量高,芳烃、不饱和烯烃含量多,致使产品味道大、毒性强、颜色重,虽然能够满足溶解性和经济性的需要,但远远不能满足特殊场合的需要。尤其是加入WTO以后,世界经济一体化,溶剂油产品的质量标准逐步提高,我国特殊场合的溶剂油几乎全部依赖进口。

简介：Byemployingaradiofrequency(RF)feedbackchain,theself-interferencecanbecanceledefficientlyinco-timeco-frequencyfullduplex(CCFD).However,theevitablesignalcrosstalkwhichiscausedbytheimperfectRFfeedbackchainisolationusuallydamagestheself-interferencecancelation(SIC)performance.Todealwiththisproblem,firstly,weanalyzetheimpactofRFfeedbackchainisolationonSICperformance.ThenadigitalpreprocessingschemewithRFfeedbackchainisproposedinthemultiple-antennaCCFDarchitecture.Usingbothanalyticalandexperimentalmethods,wefindthattheproposedschemeachievesabetterperformanceonSIC.

简介：本文主要阐述了常用不燃型溶剂清洗剂的基本组成、配比、技术指标、去污能力并介绍其它一些型号不燃型溶剂清洗剂的情况.

简介：文章介绍了替代CFC-113和1,1,1-三氯乙烷使用的新型氟系溶剂含氢氟氯烃、全氟烃和全氟醚的主要性能特点,并根据在国外的应用实际情况着重介绍了他们的应用技术和使用中应注意的问题

简介：乳酸酯清洗剂的英文名为cleaneroflactate。乳酸又称2-羟基丙酸和丙醇酸，其特点是在分子中含有羟基，所以具有较好的亲水性。一般羧酸生成的酯类多是不溶于水的，但乳酸酯有一定的水溶性。常用的乳酸酯清洗剂是乳酸乙酯，由于乳酸酯分

简介：本文主要介绍了溶剂型清洗剂的几个共同的技术标准,同时分别讨论了这几项技术标准对清洗质量的影响和它的重要性.并建议溶剂型清洗剂对这些指标的控制值和它们的测试方法以及对清洗剂进行相关的毒性实验.

简介：Asignalwaveformrecoverymethodbasedonthecoprimearrayisinvestigatedtoextractthewaveformofthedesiredsignalfromspatialinterferencesinnarrowbandscenarios.Thedirectionofarrivals(DOAs)ofthedesiredsignalandinterferencesignalsareestimatedwiththecompressivesensingapproachbasedonanglegrids,andthesignalpowertogetherwiththenoisepowerareestimated.Thereafter,amodifiedsteepestdescent(SD)methodisderivedtorecoverthewaveformofthedesiredsignalandinterferencesutilizingtheestimatedpoweranddirections.Therecoveredwaveformofthedesiredsignalistheoutputoftheproposedmethod.Thesituationinwhichthesignalsarenotonthepredefinedanglegridsisalsoconsidered.TheDOAsestimatedpredefinedanglegridsisalsoconsidered.TheDOAsestimatedlikelihood(ML)angleestimation.Comparedtotheexistingbeamformingmethodsonco-primearray,theproposedmethodcanobtainthewaveformofthedesiredsignal.Simulationresultsdemonstratethattheproposedmethodcanachievegoodperformanceinsignalwaveformrecoveryandoutputsignaltonoiseratio.

简介：Cu-andCo-substitutedNiZnferritethinfilms,Ni0.4-xZn0.6CuxFe2O4andNi0.5Zn0.5CoxFe2-xO4(0≤x≤0.2),aresynthesizedbysol-gelprocess.ThecrystallographicandmagneticpropertiesofCu-andCo-substitutedNiZnferritethinfilmshavebeeninvestigated.ThelatticeparameterdecreaseswithCusubstitutionandincreaseswithCosubstitution.ThesaturationmagnetizationdecreasesandthecoercivityincreaseswiththeincreaseofCusubstitution.Moreover,thesaturationmagnetizationgraduallyincreaseswiththeincreaseofCosubstitutionwhenx≤0.10,butdecreaseswhenx>0.10.Meanwhile,thecoercivityinitiallydecreaseswiththeincreaseofCosubstitutionwhenx≤0.10,butincreaseswhenx>0.10.

简介：本文简要阐述了碳氢溶剂作为清洗剂的特性和应用,介绍了作为CFC-113的永久性替代品萜烯碳氢清洗剂在一次性医疗器械等精密清洗中的应用前景.

简介：Dispersionandnonlineardistortionhaveaneffectontransmissionperformancesofopticalfibertransimissionsystems,Theschemesofdispersioncompensationandnonlineardistortionself-compensationintelecom-CATVco-networktransmissionsystemsarereported,followedbyinvestigationon(1)theimpactofdispersioncompensationfiber(DCF)onfibernonlineareffectswithacascadeoferbium-dopedfiberamplifiers(EDFAs)anddifferentdispersioncompensationschemes,(2)theimpactofthecomplexonthetotalnonlineardistortioninducedbyEDFAgaintiltandthelightsource.Asaresult,dispersioncompensationoptimalschemeandEDFAnegativegaintiltaresuggestedasasolutiontodispersioncompensationoptimalschemeandEDFAnegativegaintiltaresuggestedasasolutiontodispersioncompensationandthenonlineardistortionself-compensation.

简介：Aimingattheproblemofthepeaktoaveragepowerratio（PAPR）incoherentopticalorthogonalfrequencydivisionmultiplexing（CO-OFDM）,ahybridPAPRreductiontechniqueoftheCO-OFDMsystembycombiningiterativepartialtransmitsequence（IPTS）schemewithmodifiedclippingandfiltering（MCF）isproposed.Thesimulationresultsshowthatatthecomplementarycumulativedistributionfunction（CCDF）of104,thePAPRofproposedschemeisoptimizedby1.86dBand2.13dBcomparedwiththoseofIPTSandCFschemes,respectively.Meanwhile,whenthebiterrorrate（BER）is10^-3,theopticalsignaltonoiseratio（OSNR）areoptimizedby1.57dBand0.66dBcomparedwiththoseofCFandIPTS-CFschemes,respectively.

简介：ThemicrostructureandopticalpropertiesofaburiedlayerformedbyO+(200keV,1.8×1018/cm2)andN+(180keV,4×1017/cm2)co-implantationandannealedat1200℃for2hhavebeeninvestigatedbyAugerelectron,IRabsorptionandreflectionspectroscopicmeasurements.TheresultsshowthattheburiedlayerconsistsofsilicondioxideandSiOx（x<2）andthenitrogensegregatestothewingsoftheburiedlayerwhereitformsanoxynitride.BydetailtheoreticalanalysisandcomputersimulationoftheIRreflectioninterferencespectrum,therefractiveindexprofilesoftheburiedlayerwereobtained.

简介：2003年，中国IT服务市场规模呈大幅上升趋势，IT服务正成为IT产业中一个强势增长的市场。特别是随着我国企业信息化的逐步深入，信息化应用和解决方案将会掀起新一轮发展热潮，并将与电子政务一同为IT服务商提供巨大商机。

简介：2004年，宽带市场发展的主要动力来源于固网运营商的推动和市场需求的拉动。宽频娱乐、游戏将是宽带消费的一大热点，娱乐与体育竞技类的服务也是今年宽带内容消费的一大方向。

简介：Linearcomplexityandk-errorlinearcomplexityofthestreamcipheraretwoimportantstandardstoscaletherandomicityofkeystreams.Forthe2n-periodicperiodicbinarysequencewithlinearcomplexity2n1andk=2,3,thenumberofsequenceswithgivenk-errorlinearcomplexityandtheexpectedk-errorlinearcomplexityareprovided.Moreover,theproportionofthesequenceswhosek-errorlinearcomplexityisbiggerthantheexpectedvalueisanalyzed.