学科分类
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500 个结果
  • 简介:Puretungsten(PW)andW-1wt%La2O3(WL10)werepreparedbypowdermetallurgicalroutefollowedbytheswaging+rollingprocess.Thelogarithmicstrainsare0,0.37,0.58,and0.98forWL10and0,0.58forPW.Heattreatmentswereperformedattemperaturesvariedfrom1,573to2,173Ktodeterminetherecrystallizationtemperature.Recrystallizationtemperaturesare1,973and2,173KforWL1(logarithmicstrainof0.37)andWL3(logarithmicstrainof0.98),respectively.ButinthecaseofWL2(logarithmicstrainof0.58),fullrecrystallizationisnotachievedattemperatureofabove2,173K.Furthermore,therecrystallizationtemperatureofPWwithlogarithmicstrainof0.58isatleast300KlowerthanthatoftheequivalentWL10sample.Moreover,theincreaseofrecrystallizationtemperatureinhibitsthestrengthdegradationofWL2:sampleslose4%and22%strengthwhenannealedat1,573and1,973Kcomparedwithroomtemperature(RT)sample.Finally,thetextureevolutionfortheswaged+rolledWL10issignificantlyrelatedtothedeformationdegree:thedominatedorientationis<001>forWL2while<110>forWL3.

  • 标签: 再结晶温度 变形程度 纯钨 对数应变 轧制工艺 强度退化
  • 简介:Weconsideronesourceofdecoherenceforaquantumcomputercomposedofmanytrappedionsduetothethermaleffectsofthesysteminthepresenceoflaser-ioninteraction.Theupperlimitofthetemperatureatwhichthelogicalgateoperationscouldbecarriedoutreliablyisgiven,andourresultisagreementwiththeexperiment.

  • 标签: 量子计算机 离子陷阱 温度效应
  • 简介:BasedonNCEP/CFSR0.5°reanalysisdataandthebesttrackdatafromtheJapanTokyoTyphoonCenter,compositeandcomparativeanalysesdemonstratetheasymmetricalstructuresofthetemperatureandhumidityintropicalcyclonesovertheWesternNorthPacificandtheSouthChinaSeafrom1979to2010.Theresultsareshownasfollows.(1)Withintensifyingtropicalcyclones,theflowfieldtendstobecomegraduallymoreaxisymmetric;however,theasymmetryofthespecifichumidityintheouterregionsismoreobvious.(2)Ingeneral,tropicalcycloneshaveanon-uniform,vertical,'doublewarm-core'structure.The'warm-cores'inthelowerlevelofweaktropicalcyclonesandinthehigherlevelofstrongtropicalcyclonesarethestrongerofthetwo.(3)Thedistributionareaofa'warm-core'isenhancedwithcycloneintensificationandtendstobecomemoreaxisymmetric.At200hPa,the'warm-core'ofaweakcyclonehasaweakanticycloneinthecenter,whereasthatofastrongcyclonehasaweakcycloneinthecenter.(4)The'wet-core'ofatropicalcycloneisprimarilylocatedinthelowerlevel(700-850hPa).Withthecyclone’sintensification,theintensityofthe'wet-core'increasesandthescopeofthe0.8gkg-1specifichumidityanomalytendstoexpandtohigherlevels.(5)Withthecyclone’sdeepening,thepseudo-equivalentpotentialtemperatureatdifferentlevelsindifferentregionsincreases.Inaddition,thelargestwarmingratesateachintensitylevelinthedifferentregionsoccurinthecorearea,followedinturnbytheenvelopeandouterareas.

  • 标签: TROPICAL CYCLONES asymmetrical structure warm-core wet-core
  • 简介:Theviscosityoffivebitumenswasmeasuredatdifferenttemperaturesandtheviscosity-temperaturerelationshipwasdevelopedtoevaluatethetemperaturesusceptibilityofdifferentbitumens.Thegenericfractions(ie,saturates,aromatics,resinsandasphaltenes)ofthebitumenswereseparatedandtestedbythin-layerchromatographywithflameionizationdetection(TLC-FID)andtheeffectofchemicalcompositionsontemperaturesusceptibilityofbitumenswasanalyzedusingthelinearregressionmethod.Theexperimentalresultsshowthatthefourgenericfractionsplayaninconsistentroleinthetemperaturesusceptibilityofbitumensandthecorrelationdegreeofeachfractionissomewhatdifferent.Theexistenceofaromaticsandasphaltenescanlowerthesensitivitytotemperaturechangeswhereassaturatesandresinsmayhaveanadverseimpactonthetemperaturesusceptibilityofbitumens.Asforthecorrelationdegrees,resinsshowtheclosestcorrelationwiththetemperaturesusceptibilityofbitumens,thenasphaltenesandaromatics,andthecorrelationbetweentemperaturesusceptibilityandsaturatesisrelativelyweak.

  • 标签: 温度敏感性 沥青组分 化学成分 火焰离子化检测器 薄层色谱 线性回归法
  • 简介:Inthispaper,theresponseoftheatmospheric3-5yearcycletoNorthernPacificSSTisdiscussed,Theresultsareasfollows:1.FromthesimultaneoustemporalcorrelationsbetweentheEquatorialEasternPacificSST,thewesterlydirftarea’sSSTandtheNorthernPacificSSTatallgridpoints,wefindthattherearethreecorrelativeregionsintheNorthernPacificSSTfield,theyarethewesterlydriftarea,theEquatorialEasternPacificandtheAlaskaBay,andtheirstructuresareverysimilartothePNApatternintheatmosphereThedifferencePTIbetweentheEquatorialEasternPacificSSTanomalyandthewesterlydriftarea’sSSTanomalycanindicatethechangeofthePNApatternoftheNorthernPacificSSTanomaly.ItcanrepresentSSTchangeof65%areasovertheNorthernPacificandcankeepwatchonElNinoandun-ElNino.2.SimultaneoustemporalcorrelativefieldbetweenPTIandfiltered500hPa(thereis3-5yearcycleonly)oftheNorthernHemispherepresentsclearPNAstructure.Theresp

  • 标签: correlative filtered simultaneous ANOMALY DRIFT watch
  • 简介:消费者们对容易腐烂的食物的质量给予越来越多的注意,它被存储温度主要影响。这份报纸在温度控制下面为容易腐烂的食物论述一个动态定价模型。为了最大化全部的利润,最佳的价格和存储,温度用Pontryagins最大的原则被获得。一个静态的定价模型被提供与动态的作比较。它被动态政策能比静态的使更多的收入成为的一个数字例子显示出。而且,经理的含意被分析,建议方法的有效性被表明。

  • 标签: 易腐食品 温度控制 动态定价 储存温度 定价模式 最大值原理
  • 简介:Athree-dimensionalsimulationmodelfortheplasma-MIGweldingprocess,whichtakestheinteractionbetweentheplasmaarcandMIGarcintoaccount,ispresentedandthequasi-steadytemperaturefieldsontheworkpiecearecalculatedwiththemodel.The10mm-5A06aluminumalloyisweldedandthetemperaturefieldsaremeasuredwiththethermoelectriccouple.Thesimulationresultsandmeasuredresultsshowthatthebiggestdeviationofpeaktemperaturebetweenthemisbelow20℃,whichindicatesgoodcoincidencebetweenthesimulationandmeasurement.

  • 标签: 等离子体-MIG焊接 温度场 热电偶 热源模型
  • 简介:到水泥的动态性质使遭到了到冲动的装载的学习,在不同速度的水泥的压力时间曲线用裂口Hopkinson压力酒吧(SHPB)被测量。动态收益力量和水泥的组成的关系上的温度和紧张率的效果被分析。当它在相对低的温度时,增强的水泥的动态机械性质被使遭到高拉紧率。但是与温度增加,弄软效果的温度做水泥的力量变弱并且水泥的影响坚韧是突出地相对紧张率效果。那么,拉紧率效果,紧张变硬和在在他们之间的水泥和关系的动态机械能力上一起弄软工作的温度是相对复杂的。

  • 标签: 混凝土 温度效应 应变率效应 动态性能 SHPB
  • 简介:DetailedanalysisontransientcharacteristicsofECLcircuitsareperformedinthispaper,thenarelativelyexactpropagationdelayexpressionappliedforalltemperaturesispresented.Thecryogeniccharacteristicsofsomedominantparameterscontributedtopropagationdelayarealsodiscussed.Themodelachievedissuitableforoptimumdesignsofhighspeeddevicesandcircuitsatalltemperatures.

  • 标签: ECL CIRCUIT Low temperature TRANSIENT CHARACTERISTIC
  • 简介:统计downscaling的二条途径在19602008期间在夏天在北京车站基于每日的最大、最小的温度观察的百分位数被用于温度极端的索引。一个人到过由起初使用文件结束分析和逐步的线性回归的下阶层的每天最大、最小的温度,然后计算极端的索引;其它到过直接下阶层由使用季节的大规模温度和geo潜在的高度记录的基于百分位数的索引。交叉验证结果证明后者途径比前者有更好的表演。然后,后者途径在北中国被用于48个气象学的车站。所有48个车站的交叉验证结果显示出在基于百分位数的索引和季节的大规模变量之间的靠近的关联。最后,在北中国的温度极端的索引的未来情形被把统计downscaling用于哈德利中心投射联合模型版本3(HadCM3)在代表性的集中小径下面的模拟4.5(RCP4.5)第五的情形联合了模型内部比较的工程(CMIP5)。结果证明每日的最大的温度的第90百分位数将在所有地s珀?珀由大约1.5talSe增加吗??

  • 标签: 应用统计 极端温度 中国北方 降尺度 气象观测站 夏季
  • 简介:一系列随机的共聚物(PCLA)被D,L减水乳酸(LA)和-caprolactone(CL)的戒指洞聚合与不同臼齿的比率综合。PCLA基于聚氨酯(PCLAU)被获得由有hexamethylenediisocyanate(HDI)的PCLA和polytetramethylene醚(PTMEG)扩大链。所有PCLAU超过98%与高形状固定性比率展出好形状记忆性质,在第一的超过82%的形状恢复比率骑车,91%在第二骑车。有更少的CL内容的PCLAU证明有更多的CL内容的更快的恢复速度和PCLAU显示出更高的形状恢复比率。扳机温度能被以CL调整LA的臼齿的比率在身体温度附近调节或控制。PCLAU有潜在的应用在植入生物医学的设备,特别为最低限度地侵略的可部署的设备。

  • 标签: 形状记忆聚氨酯 可生物降解 温度 触发 六亚甲基二异氰酸酯 聚氨酯材料
  • 简介:Onthebasisofthequantizationofmesoscopicbiologicalcellequivalentcircuit,westudiedthequantumfluctuationsofvoltageandcurrentofmesoscopicbiologicalcellequivalentcircuitasfinitetemperaturebyBogoliuovtransformation.Theresultshowsthatthequantumfluctuationsofvoltageandcurrentnotonlyrelatewiththeparametersofequivalentcircuit,temperature,butalsodecaywithtime.Thisresultmayhavesignificantvalueonthedesignandapplicationofthebio-electronicapparatus.

  • 标签: 量子波动 生物细胞 生物电子 DNA 温度环境
  • 简介:Inrecentyearsperovskitesolarcellshaveattractedanincreasingscientificandtechnologicalinterestinthescientificcommunity.Itisimportanttoknowthatthetemperatureisoneofthefactorswhichhaveastrongeffectontheefficiencyofperovskitesolarcell.ThisstudycommunicatesatemperatureanalysisonthephotovoltaicparametersofCH_3NH_3PbI_3-basedperovskitesolarcellinabroadintervalfrom80to360K.Strongtemperature-dependentphotovoltaiceffectshavebeenobservedinthetypeofsolarcell,whichcouldbemainlyattributedtoCH_3NH_3PbI_3,showingaferroelectric-paraelectricphasetransitionatlowtemperature(T<160K).Anincreaseintemperatureovertheroomtemperaturedecreasedtheperovskitesolarcellperformanceandreduceditsefficiencyfrom16%to9%.Theinvestigationwithelectronicimpedancespectroscopyrevealsthatatlowtemperature(T<120K)thechargetransportlayerlimitsthedeviceperformance,whileathightemperature(T>200K),theinterfacialchargerecombinationbecomesthedominantfactor.

  • 标签: 太阳能电池 温度分析 电池效率 钙钛矿 铁电-顺电相变 金属
  • 简介:Theprincipleofanewopticalfibertemperaturetransducerispresented,andingeniousdesignschemeofthistransducerisgiven.Becausetakingthespecialmodulationandratiomeasurement,thisnewtransducerhasprovidedwithhighcharacteristics:experimentaltransmittingdistanceis500m;measurementerror,inthemeasuredtemperaturerangeof0-250℃,,islessthan±0.5℃;powerconsumptionoftheprobeislessthan300μW.Finally,somepointsoftheexperimentaregiven.

  • 标签: 光纤链路 微能量消耗 温度传感器 温度测量
  • 简介:TheArrheniuslawimpliesthatreactionrateisacontinuousfunctionoftemperature.However,thesteadylaminarflameletmodel(SLFM)doesnotexplicitlygivethisfunctionalrelationship.ThepresentstudyaddressesthisrelationintheSLFM.Itisfoundthatreactionrateisnotcontinuousinthemixture-fractionspace.Asaresult,theSLFMisunabletopredictlocalextinctionandreignition.Furthermore,weusetheunstablebranchofthe"S-curve"tofillthegapbetweensteadyburningbranchandextinctio...

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  • 简介:Theaxialandradialconvectiveflow,temperaturefluctuationanddistributionintheHMCZsiliconmeltarestudiedtentatively.Theexperimentalresultsshowthattheaxialandradialconvectivespeeds,thetempera-turevariationandtheradialtemperaturegradient,paralleltomagneticfieldandnearmeltsurface,alldecrease,buttheaxisymmetryoftemperaturedistributionnolongerexistswhenthemagneticfieldisapplied.

  • 标签: MAGNETIC FIELD Temperature distribution CONVECTIVE FLOW