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  • 简介:Theoxidationbehaviorofthreebiodieselsofdifferentorigins,viz.rapeseedoilderivedbiodiesel,soybeanoilderivedbiodieselandwasteoilbasedbiodiesel,weretestedonanoxidationtester.Thechemicalcompositionsofthebiodieselswerecharacterizedbygaschromatography.Thereafter,thestructuraltransformationoffattyacidmethylester(FAME)ofthebiodieselswasanalyzedbyaninfraredspectrometerandanultravioletabsorptionspectrometer.TheresultsdemonstratedthattheoxidationbehaviorofbiodieselsofdifferentoriginswascloselyrelatedtothecompositionanddistributionofFAMEs.HigherconcentrationofunsaturatedFAMEwithmulti-doublebondsexhibitedpooreroxidationresistance.Furthermore,cis-transisomerizationtransformationoccurredintheunsaturatedFAMEmoleculesandconjugateddouble-bondproducedduringtheoxidationprocessofbiodiesel.Greatercis-transvariationscorrespondedtodeeperoxidationdegree.ThehigherthecontentofunsaturatedFAMEwithmulti-doublebondsinabiodiesel,themoretheconjugateddoublebondswasformed.

  • 标签: 生物柴油 氧化行为 结构转变 光谱分析 脂肪酸甲酯 共轭双键
  • 简介:Objective:TomakeasummaryofthetrendsofHIV/AIDSepidemicandrouteoftransmissioninShenzhenfrom1992to2000toprovidescientificevidenceforthepolicy-makertoformulatestrategiesofHIV/AIDSpreventionandcontrolinShenzhen.Method:ToanalyzeHIV/AIDSsurveillancedatainShenzhenfrom1992to2000bysoftwareEpi-Info.Results:OnehundredandtwoHIVpositivecasesincluding18AIDScases(threecasesdeceased)wereidentifiedinShenzhenfrom1992to2000.Amongthe102cases,thoseinfectedviasexwere46.0%,intravenousdruguse42.9%.Blooddonation7.8%,bloodtransfusionrecipient3.9%,andindeterminate2%.Conclusion:InShenzhen,HIV/AIDSinfectionisspreadingandincreasingrapidly.EffectivepreventionmeasuresmustbetakentoreducetheHIVprevalenceassoonaspossible.

  • 标签: 爱滋病 人体免疫缺损病毒 HIV/AIDS 流行趋势 疾病监测 疾病预防
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  • 简介:or through a comic-strip panel. All kinds of ads can use this body copy,Advertisers use the narrative copy to tell a story. It often sets up a problem and then creates a solution using the particular sales features of the product or service. It may then suggest that the audiences use the same solution if they have that problem. Service advertisements are often written in this . For instance,is used in almost 80% the service advertisements. Institutional copy is often used to sell an idea or the merits of the organization or service rather than sales features of a particular product. Often institutional copy is also narrative in because it lends warmth to the organization. Banks

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  • 简介:length of a sentence in advertising is usually short. A sentence in daily consumer goods ads has 10.3 words on average,whereas we is used in almost 80% the service ads in the corpus. The following are some examples.,no introduction of a product is necessary in headline

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  • 简介:there are some differences in the use of these pronouns in the three kinds of advertisements. The first person we almost never occurs in daily consumer goods ads and technical equipment ads,length of a sentence in advertising is usually short. A sentence in daily consumer goods ads has 10.3 words on average,compound words turn up in 65% technical equipment ads

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  • 简介:Stretchableelectronics,whichofferstheperformanceofconventionalwafer-baseddevicesandmechanicalpropertiesofarubberband,enablesmanynovelapplicationsthatarenotpossiblethroughconventionalelectronicsduetoitsbrittlenature.Oneeffectivestrategytorealizestretchableelectronicsistodesigntheinorganicsemiconductormaterialinastretchableformatonacompliantelastomericsubstrate.Engineeringthermalmanagementisessentialforthedevelopmentofstretchableelectronicstoavoidadversethermaleffectsonitsperformanceaswellasinapplicationsinvolvinghumanbodyandbiologicaltissueswhereeven1–2°Ctemperatureincreaseisnotallowed.Thisarticlereviewstherecentadvancesinthermalmanagementofstretchableinorganicelectronicswithfocusesonthethermalmodelsandtheircomparisonstoexperimentsandfiniteelementsimulations.

  • 标签: 电子技术 可拉伸 热分析 机械物理性能 应用程序 半导体材料
  • 简介:Thispaperpresentsakinematicanalysisofthelocomotionofagecko,andexperimentalverificationofthekinematicmodel.Kinematicanalysisisimportantforparameterdesign,dynamicanalysis,andoptimizationinbiomimeticrobotresearch.Theproposedkinematicanalysiscansimulate,withoutiteration,thelocomotionofgeckosatisfyingtheconstraintconditionsthatmaintainthepositionofthecontactedfeetonthesurface.Sothemethodhasanadvantageforanalyzingtheclimbingmotionofthequadrupedmechanisminarealtimeapplication.Thekinematicmodelofageckoconsistsoffourlegsbasedon7-degreesoffreedomspherical-revolute-sphericaljointsandtworevolutejointsinthewaist.Themotionofthekinematicmodelissimulatedbasedonmeasurementdataofeachjoint.Themotionofthekinematicmodelsimulatestheinvestigatedrealgecko’smotionbyusingtheexperimentalresults.Theanalysissolvestheforwardkinematicsbyconsideringthemodelasacombinationofclosedandopenserialmechanismsundertheconditionthatmaintainsthecontactpositionsoftheattachedfeetontheground.Themotionsofeachjointarevalidatedbycomparingwiththeexperimentalresults.Inadditiontothemeasuredgait,threeothergaitsaresimulatedbasedonthekinematicmodel.Themaximumstridesofeachgaitarecalculatedbyworkspaceanalysis.Theresultcanbeusedinbiomimeticrobotdesignandmotionplanning.

  • 标签: kinematic ANALYSIS locomotlon of GECKO LIZARD
  • 简介:Inthispaper,weconstructaclassofnowheredifferentiablecontinuousfunctionsbymeansoftheCantorseriesexpressionofrealnumbers.Theconstructedfunctionsincludesomeknownnondifferentiablefunctions,suchasBushtypefunctions.Thesefunctionsarefractalfunctionssincetheirgraphsareingeneralfractalsets.Undercertainconditions,weinvestigatethefractaldimensionsofthegraphsofthesefunctions,computetheprecisevaluesofBoxandPackingdimensions,andevaluatetheHausdorffdimension.Meanwhile,theHoldercontinuityofsuchfunctionsisalsodiscussed.

  • 标签: CANTOR series expression DYADIC NONDIFFERENTIABLE FRACTAL
  • 简介:敏感的二种类型为静态地稳定的sailcrafts被建议。一种类型是关于质量的中心的位置的solar-radiation-pressure力量的敏感,并且另外的类型是关于态度的solar-radiation-pressure力量的敏感。敏感的二种类型代表solar-radiation-pressure力量怎么随着集体中心和态度的位置变化。有更大的敏感的Sailcrafts经历solar-radiation-pressure力量的更大的错误,导致更大的轨道错误,,由模拟示威了。然后作为案例研究,详细公式被导出与四张三角形的风帆为sailcrafts计算敏感。根据这些公式,敏感打字以便减少两个,在反对风帆之间的角度不应该太大,并且质量的中心应该远是离四张风帆并且尽可能的对称的轴尽可能靠近的离开sailcraft的压力的中心。

  • 标签: 敏感性分析 静态稳定 类型 辐射压力 重心位置 公式推导
  • 简介:Aninnovativefloatingmooringsystemwithtwoormoreindependentfloatingmooringplatformsinthemiddleandonerigidplatformoneachsideisproposedforimprovingefficiencyandsafetyinshallowwater.Forthisnewsystem,mostofcollisionenergyisabsorbedthroughthedisplacementoffloatingplatforms.Inordertoillustratethevalidityofthesystem,aseriesofmodeltestswereconductedatascaleof1:40.Thecoupledmotioncharacteristicsofthefloatingmooringplatformswerediscussedunderregularandirregularwaves,andtheinfluencesofwavedirectionandothercharacteristicsondynamicresponseofthesystemwereanalyzed.Theresultsshowthatthemooringsystemissafestat0°ofwaveincidentangle,whereasthemostdangerousmooringstateoccursat90°ofwaveincidentangle.Motionresponsesincreasewiththeincreaseofwaveheight,butarenotlinearlyrelatedtochangesinwaveheight.

  • 标签: 系泊系统 动力响应分析 浮式平台 运动特性 碰撞能量 模型试验
  • 简介:东廷·莱克的沉积来自四条隧道(他们之一在1959被关上),与长江连接了,四条支流(Lishui,Yuanjiang,Zishui和Xiangjiang)和本地区域,和他们中的一些在Chenglingji被搬运进长江,它在东廷·莱克,的出口被定位他们中的一些在湖区域和剩余的存款扔进排水系统进湖。年度吝啬的沉积是166,555xl04t,80%来自四条隧道,18%从四条支流并且2%从本地区域,而26%全部的沉积被搬运进长江,74%扔了进湖和湖排水系统。基于上1974,1988和1998的地志的地图,和有地理信息系统(GIS)的空间分析方法,在沉积免职和侵蚀的变化在这份报纸被学习。由1974和1988的覆盖分析,1988和1998,侵蚀和沉积免职区域被定义。主要结论是:(1)在湖的沉积率比从1974~1998的侵蚀率大。在湖的吝啬的免职是0.43m;(2)年度沉积免职是在1974鈥?之间的一样988和1988鈥?998,但是免职的年度体积和998是的1988鈥?的侵蚀比那大在1974鈥?988;(3)在三的结束塞满水库以前,将有7.82xl08m3of沉积,在湖扔,它将由0.33m使湖成为silted起来;(4)在湖,免职区域在东方东廷·莱克,南方东廷·莱克的西南,和西方东廷·莱克的东方的北方被发现;当侵蚀的区域在东方东廷·莱克的南方时,南方东廷·莱克,西方东廷·莱克的西方,以及Xiangjiang和Lishui河洪水隧道的中间。

  • 标签: Dongting LAKE SEDIMENT DEPOSITION and EROSION
  • 简介:TheAnapleprojectisanongoingefforttoprovideanObjectOrientedsoftwareenvironmentfordataanalysisinHENPexperiments,Arangeofcommercialandpublicdomainlibrariesisusedtocoverbasicfunctionalities;ontopoftheselibrariesasetofHENP-sepcificC++classlibrariesforhistogrammanagementfitting,plottingandntuple-likedataanalysishasbeendeveloped.Inordertocomplywiththeuserrequireementsforacommand-linedriventool,wehavechosentouseascriptinglanguage(Python)asthefromt-entforadataanalysistool.Theloosecouplingprovidedbytheconsequentuseof(AIDAcompliant)AbstractInterfacesforeachcomponentincombinationwiththeuseofsharedlibrariesfortheirimplementationproviesaneasyintegrationofexistinglibrariesintomodernsciptinglanguagesthusallowingforrapidapplicationdevelopment.Thisintegrationissimplifiedevenfurthersuingaspecialisedtoolkit(SWIG)tocreate"shadowClasses"forthePythonlanguage,whichmapthedefinitionsoftheAbstractInterfacesalmostataone-to-onelevel.Thispaperwillgiveanoverviewofthearchitectureanddesignchoicesandwillpresentthecurrentstatusandfuturedevelopmentsoftheproject.

  • 标签: HENP实验 OO图书馆数据库 数据分析工具 目标取向
  • 简介:length of a sentence in advertising is usually short. A sentence in daily consumer goods ads has 10.3 words on average,there are some differences in the use of these pronouns in the three kinds of advertisements. The first person we almost never occurs in daily consumer goods ads and technical equipment ads,descriptive adjectives and evaluative adjectives. The former is used in objective description and the latter give the advertiser’s subjective comments. Then we have listed those frequently used descriptive adjectives and evaluative adjectives in daily consumer goods ads and technical equipment ads

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  • 简介:and language. It is a more common case that an advertisement is a mixture of the three. In radio advertisements,1976). The use of weasel words has become a device in advertising. Weasel words make people hear things that aren’t being said,by a contrastive study of advertisements on three types of products (daily consumer goods

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  • 简介:the body copy is a logical continuation of the headline and subheads. It is also where the sale is closed. The body copy should relate to the campaign appeal and to the reader’s self-interest,or through a comic-strip panel. All kinds of ads can use this body copy,headlines of technical equipment ads mean to attract readers by displaying the unknown information of a product. 

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