简介：化合物半导体相比硅半导体具有高频率、大功率等优异性能，是未来5G通信不可替代的核心技术，将在5G通信中大量使用。

简介：本文详细介绍了碳氢化合物的结构与清洗性能之间的关系.指出清洗剂的组成及其分子结构不同会有不同的物理性质和化学性质.建议用户应依据清洗剂的性质来拟定工艺流程和工艺参数.

简介：1.前言由于近几年来汽车的性能不断提高,采用减少污染环境的新技术,汽车制造工艺的质量管理显得极为重要,与质量管理有关的清洗工艺的重要性也越来越突出.

简介：所有纤维基于Er~(3+)：Yb~(3+)共同做在1550nm操作的两倍穿着的光纤激光器被表明。由使用9m渴望Er~(3+)：Yb~(3+)共同做纤维(EYDF)著名计算机生产厂商他获得媒介，并且当波长过滤，用一双纤维布拉格栅栏，产量激光的线宽象0一样狭窄。2nm和产量力量是超过6mW。在它的排放前的激光的荧光灯的效果也被学习。并且它被发现Er~(3+)：Yb~(3+)共同做双clad光纤激光器也在1080nm附近为Yb~(3+)转变展出高获得。

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

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

简介：没有增加反馈调制轻路径系统，非对称3×3联合光加速表减少光的设计的复杂性路径系统。实验证明它能达到好解调效果。当搬运人不在这个系统被需要，输入信号的频率范围被减少以便减少加速表的采样频率。这在可编程的薄片(SOPC)上为系统做数字使解调的设计系统。加速表工作频率罐头活动范围3500Hz的上面的限制。但是由敏感部件的固有的频率影响了，它的工作频率是10Hz～1000Hz，和敏感是8。7180V/(m？s~(-2))。这张加速表能检测加速信号的动态范围真实及时，稳定地并且精确地，解决轻路径的非对称的问题由情形和进程的复杂性引起了。

简介：文章回顾了洗涤剂的发展历史,并用大量事实说明随着石化工业发展起来的石化合成洗洁剂,虽然给人的生活带来许多便利,但同时也造成对环境的污染和对人体健康的危害,应该引起人们的高度警惕,并指出用天然洗剂替代石化合成洗洁剂是洗洁剂今后发展的必然方向.

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

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

简介：文章回顾了石化合成洗剂的发展历史,从经历的五代产品的发展过程中可以看出它经历了一个环保到不环保再到环保的曲折过程;分析了石化合成洗剂的主要成分及其清洗去污的作用原理着重指出目前使用的石化合成洗剂虽然给生活带来便利,但同时也给人体健康和生态环境都造成严重的危害;倡导使用新型环保型的第五代洗剂已成为新世纪中清洗剂发展的必然趋势.

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.

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简介：ResearchandMarkets最新研究了未来移动通信的发展、以及驱动移动通信向后3G发展的因素。

简介：没有几家公司能够在7年时间里安装五台小森印刷机．而WalshColourPrint公司就做到了。该公司于近日为自己的生产线引进了一台带有涂布装置的五色LithroneS29B2印刷机．除了这台新设备以外．该公司还拥有一台BI八色LithroneLS840双面印刷机．一台十色B2NL1028双面印刷机和两台四色Lithrone426印刷机。

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：本文对基于平行排列3×3耦合器的光纤器件进行了研究.平行排列3×3耦合器不仅可以实现双端口光开关、全光缓存器、光纤谐振腔等器件,而且可以用作可调耦合比的耦合器.由于平行排列3×3耦合器的弱耦合特性和平行排列结构,使得基于平行排列3×3耦合器的光器件具有许多独特的特点.更重要的是,由于这种耦合器的平行排列结构,使得它很容易做成平板波导结构,形成各种集成光器件.

简介：在这项工作中，和两个新的荧光粉发光特性的合成：Pr3＋CaYAlO4（CYA）和镨铽：CyA的发光二极管（LED）的影响。0.5%（原子百分比）Pr3＋：环孢素A具有最大的亮黄色发射不同Pr3＋浓度，根据3P0＋3H4→1G4＋1G4的交叉弛豫过程。Pr3＋的能级图：环孢素A，特别是D级和4F51S0能级位置，讨论了。通过掺杂Tb3＋离子，镨铽荧光粉的色坐标：CyA可调谐从黄色到白色区域。最后，用最强的发光色坐标（0.339，0.364）位于白色区可在0.3%Tb3＋/0.5%Pr3＋：CyA磷。