UL 497A-1990 通信电路的辅助保护装置
时间:2024-05-15 12:10:16 来源: 标准资料网 作者：标准资料网 阅读：8741
【英文标准名称】:Secondaryprotectorsforcommunicationcircuits
【原文标准名称】:通信电路的辅助保护装置
【标准号】:UL497A-1990
【标准状态】:作废
【国别】:美国
【发布日期】:1990-01
【实施或试行日期】:
【发布单位】:美国保险商实验所(UL)
【起草单位】:UL
【标准类型】:()
【标准水平】:()
【中文主题词】:电源;过电压保护装置;电信;短路保护;防护屏蔽;绝软线;低压电缆;连接电缆
【英文主题词】:short-circuitprotection;shields;telecommunications;insulatedcords;overvoltageprotection;currentsupply;connectorcables;low-tensioncables
【摘要】:
【中国标准分类号】:K45
【国际标准分类号】:29_120_50
【页数】:54P;A4
【正文语种】:英语
【英文标准名称】:Technicaldrawings--Representationofsprings
【原文标准名称】:技术制图.弹簧画法
【标准号】:JISB0004-1995
【标准状态】:作废
【国别】:日本
【发布日期】:1995-03-01
【实施或试行日期】:
【发布单位】:日本工业标准调查会(JISC)
【起草单位】:TechnicalCommitteeonMachineElements
【标准类型】:()
【标准水平】:()
【中文主题词】:工程图;弹簧
【英文主题词】:engineeringdrawings;springs
【摘要】:
【中国标准分类号】:J04
【国际标准分类号】:01_100_20
【页数】:28P;A4
【正文语种】:日语
【英文标准名称】:StandardTestMethodforMeasurementofTransitionTemperaturesofPetroleumWaxesbyDifferentialScanningCalorimetry(DSC)
【原文标准名称】:差示扫描量热法(DSC)测量石油蜡转变温度的标准试验方法
【标准号】:ASTMD4419-1990(2005)
【标准状态】:现行
【国别】:
【发布日期】:1990
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:D02.10.0A
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:旋转栅门;石蜡;润滑剂;测量;蜡;试验;石油产品;温度
【英文主题词】:differentialscanningcalorimetry;petroleumwax;thermalproperties;transitiontemperature
【摘要】:DSCinaconvenientandrapidmethodfordeterminingthetemperaturelimitswithinwhichawaxundergoesduringtransitions.Thehighesttemperaturetransitionisasolid-liquidtransitionassociatedwithcompletemelting;itcanguidethechoiceofwaxstorageandapplicationtemperatures.Thesolid-solidtemperaturetransitionisrelatedtothepropertiesofthesolid,thatis,hardnessandblockingtemperature.Note28212;Forarelativelynarrowcutpetroleumwax,thelowesttransitionwillbeasolid-solidtransition.Anarrowcutwaxisoneobtainedbydeoilingasinglepetroleumdistillatewithamaximumrangeof120x00B0;Fbetweenits5%and95%volinaccordancewithTestMethodD1160boilingpoints(convertedto760torr).TheDSCmethodcannotdifferentiatebetweensolid-liquidandsolid-solidtransitions.Suchinformationmustbepredeterminedbyothertechniques.Inthecaseofblends,thelowertemperaturetransitionmaybeenvelopesofbothsolid-liquidandsolid-solidtransitions.Sincepetroleumwaxisamixtureofhydrocarbonswithdifferentmolecularweights,itstransitionsoccuroveratemperaturerange.Thisrangeisonefactorthatinfluencesthewidth,expressedinx00B0;C,oftheDSCpeaks.Thehighesttemperaturetransitionisafirst-ordertransition.If,foraseriesofwaxes,thereissupportingevidencethatthehighesttemperaturetransitionofeachwaxisthemajorfirst-ordertransition,itsrelativewidthshouldcorrelatewiththerelativewidthofthewax’molecularweightdistribution.1.1Thistestmethodcoversthetransitiontemperaturesofpetroleumwaxes,includingmicrocrystallinewaxes,bydifferentialscanningcalorimetry(DSC).Thesetransitionsmayoccurasasolid-solidtransitionorasasolid-liquidtransition.1.2Thenormaloperatingtemperaturerangeextendsfrom15Cto150C(Note1).1.3ThevaluesstatedinSIunitsaretoberegardedasthestandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:E42
【国际标准分类号】:75_140
【页数】:4P.;A4
【正文语种】: