简介：电子电路曲面结构对于实现结构功能一体化有重要应用意义。针对LTCC多层电路基板,提出了一种曲面结构基板的加工制造方法。介绍其制造中曲面结构导体制作、曲面结构成形、曲面结构烧结等环节的关键制造工艺。通过X光和剖切方式对所制造的曲面基板进行测试分析,结果证实曲面基板中的多层布线均连通,且层间对位精度优于15μm。提出的曲面LTCC基板制造技术能够满足后续产品的研制加工要求,对于曲面电子技术和LTCC技术的发展都具有借鉴意义。

简介：机载、星载、舰载相控阵雷达由于其特定的使用环境,需要体积小、重量轻、高性能、高可靠、低成本的微波组件。带腔体LTCC基板具有高密度布线、电阻、电容、电感的内埋以及芯片的埋置等特性,是制作机载、星载、舰载相控阵雷达微波组件理想的高密度基板。针对带腔体LTCC集成基板的制造技术,简单介绍其工艺流程,并对腔体成型这项关键工艺进行了分析,提出了相应的解决方法。

简介：Wesuggestalowcross-talkplasmoniccross-connectorbasedonametal/insulator/metalcavityandwaveguides.Weseparatelyinvestigatetheisolatedcavitymode,thewaveguidemode,andthecombinationofcavityandwaveguidemodesusingafinite-differenttime-domainmethod.Duetoresonanttunnelingandthecutofffrequencyoftheoddwaveguidemode,ourproposedstructureachievesahighthroughputtransmissionratioandeliminatescross-talk.Furthermore,theproposedstructurehasabroadbandtunabilityof587nm,whichcanbeachievedbymodulatingthecavityairgapthickness.Thisstructureenablestheminiaturizationofphotonicintegratedcircuitsandsensingapplications.

简介：超高导热陶瓷基板因其优良的导热性能已逐渐应用于PCB制造业。文章介绍了业界陶瓷基板的发展状况，并基于实际应用对其未来的发展做了探讨。

简介：Mixedmetaloxidesinthenanoscaleareofgreatinterestformanyaspectsofenergyrelatedresearchtopicsaswatersplitting,fuelcellsandbatterytechnology.Thedevelopmentofscalable,cost-efficientandrobustsyntheticroutestowardwell-definedsolidstatestructuresisamajorobjectiveinthisfield.Whilemonometallicoxideshavebeenstudiedinmuchdetail,reliablesyntheticrecipestargetingspecificcrystalstructuresofmixedmetaloxidenanoparticlesarelargelymissing.Yet,inordertomeettherequirementsforabroadrangeoftechnicalimplementationitisnecessarytotailorthepropertiesofmixedmetaloxidestotheparticularpurpose.Here,wepresentastudyontheimpactofthenatureofthegasenvironmentontheresultingcrystalstructureduringapost-synthesisthermalheattreatmentofmanganese–cobaltoxidenanoparticles.Wemonitortheevolutionofthecrystalphasestructureasthegasatmosphereisalteredfrompurenitrogentosyntheticairandpureoxygen.Theparticlesizeandhomogeneityoftheresultingnanoparticlesincreasewithoxygencontent,whilethecrystalstructuregraduallychangesfromrocksalt-liketopurespinel.Wefindthecompositionoftheparticlestobeindependentofthegasatmosphere.Themanganese–cobaltoxidenanoparticlesexhibitedpromisingelectrocatalyticactivityregardingoxygenevolutioninalkalineelectrolyte.Thesefindingsoffernewsynthesispathwaysforthedirectpreparationofversatileutilizablemixedmetaloxides.

简介：本论文对近年毫米波电路基板市场的迅速扩大的背景下,对应用于毫米波电路的高频微波型覆铜板技术的发展作以综述。并对其发展趋势、特点作了分析。

简介：针对门业板边部翘皮和黑斑缺陷,通过对生产工艺过程的反查和试验对比研究,阐明了板坯边部裂纹是门业板基板边部产生翘皮和黑斑缺陷的根源,而钢中硫含量高、Mn/S偏低是门业板板坯裂纹产生的主要原因,且板坯加热温度在1170~1200℃时可以有效减轻此类缺陷。

简介：本论文对近年毫米波电路基板市场的迅速扩大的背景下,应用于毫米波电路的高频微波型覆铜板技术的发展作了综述,并对其发展趋势、特点作了分析。

简介：Lattice,charge,orbital,andspinarethefourfundamentaldegreesoffreedomincondensedmatter,ofwhichtheinteractivecouplingderivestremendousnovelphysicalphenomena,suchashigh-temperaturesuperconductivity(high-T_cSC)andcolossalmagnetoresistance(CMR)instronglycorrelatedelectronicsystem.Directexperimentalobservationofthesefreedomsisessentialtounderstandingthestructure-propertyrelationshipandthephysicsbehindit,andalsoindispensablefordesigningnewmaterialsanddevices.Scanningtransmissionelectronmicroscopy(STEM)integratingmultipletechniquesofstructureimagingandspectrumanalysis,isacomprehensiveplatformforprovidingstructural,chemicalandelectronicinformationofmaterialswithahighspatialresolution.Benefitingfromthedevelopmentofaberrationcorrectors,STEMhastakenabigbreakthroughtowardssub-angstromresolutioninlastdecadeandalwaysstepsforwardtoimprovethecapabilityofmaterialcharacterization;manyimprovementshavebeenachievedinrecentyears,therebygivinganindepthinsightintomaterialresearch.Here,wepresentabriefreviewoftherecentadvancesofSTEMbysomerepresentativeexamplesofperovskitetransitionmetaloxides;atomic-scalemappingofferroelectricpolarization,octahedraldistortionsandrotations,valencestate,coordinationandspinorderingarepresented.WeexpectthatthisbriefintroductionaboutthecurrentcapabilityofSTEMcouldfacilitatetheunderstandingoftherelationshipbetweenfunctionalpropertiesandthesefundamentaldegreesoffreedomincomplexoxides.

简介：Calciumhexaluminateisonefromsuchperspectivematerials.Itischaracterizedbyhighrefractoriness(above1830℃),aswellaspropertiesstabilityinreducingatmosphere,highalkali-andslag-resistance,lowthermalconductivityandwettabilitybymoltenmetals.Inthisworkinfluenceresearchesoffusedcalciumhexaluminatematerialadditiveinamountof5%,15%and25%onthemainpropertiesofaluminarefractorieswerecarriedout.Itisestablishedthat,therefractoriescontainingtheadditiveof25%calciumhexaluminatematerialarecharacterizedbythehighestproperties,slightlyimpregnatedwithmetalmeltandthehighestmetalcorrosionresistance.ThealuminapurgingplugsforblowingofmetalwithcalciumhexaluminatematerialadditiveareproducedandintendedtoonemetallurgicalplantofUkraineforcarryingouttests.

简介：Metalpollutioninaquaticecosystemsisofimmenseimportance.Undervariousenvironmentcircumstances,themetalcontentsofsedimentscanenterintotheoverlyingwaterbodyleadingtoseveretoxicity.ThisstudyaimstodeterminemetalconcentrationsinsedimentsofAnzaliInternationalWetlandinIran.Chemicalpartitioningmethodisusedtodeterminetheportionofanthropogenicpollutionandthemobilitypotentialofeachmetal.Theintensityofmetalpollutioninsedimentsofthewetlandisassessedusingthreereliableindices.TheresultsofchemicalpartitioningrevealthatcadmiumbearthehighestriskofbeingreleasedintotheaquaticenvironmentandhighamountofmanganeseinsulfidebondphaseimpliestheinitiationofredoxstateinaquaticenvironmentoftheAnzaliWetland.TheresultsofchemicalpartitioningstudiesshowthatPb,Cd,MnandAshavethehighestanthropogenicportion.Clusteranalysisalsoconfirmstheresultsofchemicalpartitioningandindicatesthatthementionedmetalscanbeoriginatedfromanthropogenicsources.Sedimentpollutionindices,including,I_geo,I_POLL,andm-ERM-Qrevealthatmetalsareintherangeoflowtomoderatepollutionandalsoshowthatthehighestmetalpollutionisintheeasternandcentralpartsofthewetland.Thiscanbeascribedtoriverswhicharetherecipientofindustrial,agriculturalandmunicipalwastewatersandflowintothesepartsofthewetland.

简介：Acomparativeoptimaldesignoffluid-saturatedprismaticcellularmetalhoneycombs(PCMHs)havingdifferentcellshapesispresentedforthermalmanagementapplications.BasedontheperiodictopologyofeachPCMH,aunitcell(UC)forthermaltransportanalysiswasselectedtocalculateitseffectivethermalconductivity.Withoutintroducinganyempiricalcoefficient,wemodifiedandextendedtheanalyticalmodelofparallel–seriesthermal–electricnetworktoawiderporosityrange(0.7~0.98)byconsideringtheeffectsoftwo-dimensionallocalheatconductioninsolidligamentsinsideeachUC.Goodagreementwasachievedbetweenanalyticalpredictionsandnumericalsimulationsbasedonthemethodoffinitevolume.Theconceptofligamentheatconductionefficiency(LTCE)wasproposedtophysicallyexplainthemechanismsunderlyingtheeffectsofligamentconfigurationoneffectivethermalconductivity(ETC).Basedupontheproposedtheory,aconstructstrategywasdevelopedfordesigningtheETCbyalteringtheequivalentinteractionanglewiththedirectionofheatflow:relativelysmallaverageinteractionangleforthermalconductionandrelativelylargeoneforthermalinsulation.

简介：Inthisstudy,theresidualstrainofathinconductivemetalwireonapolymersubstrateafterelectricalfailureismeasuredwithSEMmoir′e.Focusedionbeam(FIB)millingisappliedtofabricatemicronmoir′egratingsonthesurfacesofconstantanwiresandtherandomphaseshiftingtechniqueisusedtoprocessmoir′efringes.Thevirtualstrainmethodisbrieflyintroducedandusedtocalculatetherealstrainofspecimens.Inordertostudytheinfluenceofadefectontheelectricalfailureoftheconstantanwire,experimentswereconductedontwospecimens,onewithacrack,whiletheotheronewithoutanycrack.Bycomparingtheresults,wefoundthatthedefectmakesthecriticalbeamcurrentofelectricalfailuredecrease.Inaddition,thespecimensweresubjectedtocompressionafterelectricalfailure,inagreementwiththeobservedcrackclosureofthespecimen.Thesuccessfulresultsdemonstratethatthemoir′emethodiseffectivetocharacterizethefull-fielddeformationofconstantanwiresonthepolymermembrane,andhasagoodpotentialforfurtherapplicationtothedeformationmeasurementofthinfilms.

简介：Directelectrochemicalformationofhydrogenperoxide(H2O2)frompureO2andH2oncheapmetal-freeearthabundantcatalystshasemergedasthehighestatom-efficientandenvironmentallyfriendlyreactionpathwayandisthereforeofgreatinterestfromanacademicandindustrialpointofview.Veryrecently,novelmetal-freemesoporousnitrogen-dopedcarboncatalystshaveattractedlargeattentionduetotheuniquereactivityandselectivityfortheelectrochemicalhydrogenperoxideformation[1–3].Inthiswork,weprovidedeeperinsightsintotheelectrocatalyticactivity,selectivityanddurabilityofnovelmetal-freemesoporousnitrogen-dopedcarboncatalystfortheperoxideformationwithaparticularemphasisontheinfluenceofexperimentalreactionparameterssuchaspHvalueandelectrodepotentialforthreedifferentelectrolytes.Weusedtwoindependentapproachesfortheinvestigationofelectrochemicalhydrogenperoxideformation,namelyrotatingring-diskelectrode(RRDE)techniqueandphotometricUV–VIStechnique.Ourelectrochemicalandphotometricresultsclearlyrevealedaconsiderableperoxideformationactivityaswellashighcatalystdurabilityforthemetal-freenitrogen-dopedcarboncatalystmaterialinbothacidicaswellasneutralmediumatthesameelectrodepotentialunderambienttemperatureandpressure.Inaddition,theobtainedelectrochemicalreactivityandselectivityindicatethatthemechanismsfortheelectrochemicalformationanddecompositionofperoxidearestronglydependentonthepHvalueandelectrodepotential.

简介：我们揭示并且解释thermopowerS/T的可伸缩的行为展出了由典型重费米子(HF)金属YbRh2在在温度T的磁场B的申请下面的Si2。我们证明一样的可伸缩被不同HF混合物例如表明?-YbAlB4和强烈相关的分层的钴氧化物[BiBa0.66K0.36O2]CoO2。用YbRh2是的Si2一个例子，，我们证明S/T的可伸缩的行为在antiferromagnetic阶段转变被违背剩余抵抗力0和状态的密度，N，经验在阶段转变跳，引起thermopower做二跳并且改变它的符号。我们的说明基于深刻地影响0和N的单个粒子的光谱变平。描绘S/T行为的主要特征，我们构造TBYbRh2Si2。我们为HF混合物的计算S/T在对试验性的事实的好同意并且支持我们的观察。

简介：Thefatiguepropertiesoffrictionstirwelded(FSW)buttjointandbasemetalofMB8magnesiumalloywereinvestigated.ThecomparativefatiguetestswerecarriedoutusingEHF-EM200K2-070-1AfatiguetestingmachineforbothFSWbuttjointandbasemetalspecimens.ThefatiguefractureswereobservedandanalyzedusingascanningelectronmicroscopeofJSM-6063LAtype.TheexperimentalresultsshowthatthefatigueperformanceoftheFSWbuttjointofMB8magnesiumalloyissharplydecreased.Theconditionalfatiguelimit(2×10~6)ofbasemetalandweldedbuttjointisabout77.44MPaand49.91MPa,respectively.Theconditionalfatiguelimit(2×10~6)oftheweldedbuttjointis64.45%ofthatofbasemetal.Themainreasonsarethattheweldingcanleadtostressconcentrationintheflasharea,tensileweldingresidualstressintheweldedjoint(Theresidualstressvaluewas30.5MPa),aswellasthegrainsizeisnotuniformintheheat-affectedzone.Thecleavagestepsorquasi-cleavagepatternspresentonthefatiguefracturesurface,thefracturetypeoftheFSWbuttjointbelongstoabrittlefracture.

简介：Soilamendmentwithflyash（FA）andcombinedsupplementationwithN2-fixingcyanobacteriamassesasbiofertilizerweredoneinfieldexperimentswithrice.AmendmentswithFAlevels,0,0.5,1.0,2.0,4.0,8.0and10.0kg/m2,causedincreaseingrowthandyieldofriceupto8.0kg/m2,monitoredwithseveralparameters.PigmentcontentsandenzymeactivitiesofleaveswereenhancedbyFA,withthemaximumlevelofFAat10.0kg/m2.ProteincontentofriceseedswasthehighestinplantsgrownatFAlevel4.0kg/m2.Basicsoilproperties,pHvalue,percentageofsilt,percentageofclay,water-holdingcapacity,electricalconductivity,cationexchangecapacity,andorganiccarboncontentincreasedduetotheFAamendment.ParallelsupplementationofFAamendedplotswith1.0kg/m2N2-fixingcyanobacteriamasscausedfurthersignificantincrementsofthemostsoilproperties,andricegrowthandyieldparameters.1000-grainweightofriceplantsgrownatFAlevel4.0kg/m2alongwithcyanobacteriasupplementationwasthemaximum.CyanobacteriasupplementationcausedincreaseofimportantbasicpropertiesofsoilincludingthetotalN-content.Estimationsofelementalcontentinsoilsandplantparts（rootandseed）weredonebytheatomicabsorptionspectrophotometry.AccumulationsofK,P,Feandseveralplantmicronutrients（Mn,Ni,Co,ZnandCu）andtoxicelements（Pb,CrandCd）increasedinsoilsandplantpartsasafunctionoftheFAgradation,butNacontentremainedalmostunchangedinsoilsandseeds.Supplementationofcyanobacteriahadamelioratingeffectontoxicmetalcontentsofsoilsandplantparts.TheFAlevel4.0kg/m2,with1.0kg/m2cyanobacteriamasssupplementation,couldbetakenideal,sincetherewouldberechargingofthesoilwithessentialmicronutrientsaswellastoxicchemicalsincomparativelesserproportions,andcyanobacteriamasswouldcauselesseningtoxicmetalloadswithusualN2-fixation.

简介：迈阿密河里的沾染物的运输(佛罗里达，美国)有河水流的沉积由于他们在离开潜在的来源的区域的潜在的影响是一颗担心。五金属的累积侧面(作为，Cd，Hg，Zn，Pb)在迈阿密的地表的沉积，河在与谷物尺寸的关系被评估(从不到0.075 ；公里到6.3 ；公里)并且器官的内容。地表的沉积样品沿着河盆以及在海湾水里被收集。好沉积(<0.106 ；公里)与比0.850 大的沉积相比包含了乘Cd和Hg的层次的超过10和乘砷的层次的超过6；公里。Zn和Pb层次是在好沉积的超过10次(<0.106 ；公里)与那些相比，那比4.750 大；公里。Cd，Hg，和Zn层次与沉积的全部的器官的碳内容有重要关联。这显示在好沉积的Cd，Hg，和Zn有潜力除了与河水流要动员的潜力被使产生代射变化。解决粒子的速度的吉布斯的分析证明比0.5 小的粒子；公里能与河水流被搬运。在好沉积的重金属的层次(<0.425 ；公里)沿着河，床证明好粒子有趋势外面在河水流低、带的地点被动员并且积累到海湾。

简介：

简介：亚洲与任何另外的区域相比正在经历更快速的经济生长。有金属的土壤和地下水的污染能主要被归因于人的活动；因此，描绘风险的性质和大小到人的风险评价和从沾染物的生态的受体是重要的。风险评价经常是反复的进程，它包含鉴定和充满的数据差距。象多媒体一样的统计方法冒险评价建模的试验性的采样，geostatistical和multivariate是在土壤和地下水在对金属污染的评价使用的三主要方法论。这评论为改进风险计算方法加亮很多大小并且详细说明包含污染，暴露小径和金属的bioavailability的主要来源的鉴定的科学途径。一般来说，对在土壤和世界范围的地下水的金属的风险评价是污染，暴露小径的鉴定，和污染的概率的预言的主要集中的onthelevels。迄今为止，很有限的研究在亚洲在土壤和地下水污染的规定报导了相关环境法律和政策的发展。在在发达国家之中的土壤和地下水污染的规定的发展，变化和限制可以在亚洲为发展中的国家提供有用指导。