【英文标准名称】:Flowmeasurement-Differentialpressuredeviceswithflangestaps,nominaldiameter10to400,nominalpressure64to400-Sealingsurfacelens-shape
【原文标准名称】:流量测量技术.带法兰接口的差压装置.公称直径10至400.公称压力64至400.透镜型密封
【标准号】:DIN19214-3-1985
【标准状态】:作废
【国别】:德国
【发布日期】:1985-07
【实施或试行日期】:
【发布单位】:德国标准化学会(DIN)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:流量测量;规范(审批);法兰;有颈法兰;尺寸;孔板流量计;差动装置;流量计;尺寸公差;密封件;公差;压力;测量仪器;材料
【英文主题词】:flowmeasurements;pressure;neckflanges;flowmeters;tolerances(measurement);dimensions;differentialdevices;seals;flanges;materials;orificeflowmeters;measuringinstruments;flowmeasurement;dimensiona
【摘要】:
【中国标准分类号】:N12
【国际标准分类号】:17_120_10
【页数】:4P;A4
【正文语种】:德语


【英文标准名称】:StandardTestMethodforImpedanceandAbsorptionofAcousticalMaterialsbyImpedanceTubeMethod
【原文标准名称】:用阻抗管法测定隔音材料的声阻抗与吸音性的标准试验方法
【标准号】:ASTMC384-2004
【标准状态】:现行
【国别】:
【发布日期】:2004
【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】:E33.01
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:吸收;阻抗;材料;试验;声学
【英文主题词】:absorption;impedance;impedanceratio;impedancetube;normalincidencesoundabsorptioncoefficient;specificnormalacousticimpedance
【摘要】:Theacousticalimpedancepropertiesofasoundabsorptivematerialarerelatedtoitsphysicalproperties,suchasairflowresistance,porosity,elasticity,anddensity.Assuch,themeasurementsdescribedinthistestmethodareusefulinbasicresearchandproductdevelopmentofsoundabsorptivematerials.Normalincidencesoundabsorptioncoefficientsaremoreusefulthanrandomincidencecoefficientsincertainsituations.Theyareused,forexample,topredicttheeffectofplacingmaterialinasmallenclosedspace,suchasinsideamachine.Estimatesoftherandomincidenceorstatisticalabsorptioncoefficientsformaterialscanbeobtainedfromnormalincidenceimpedancedata.Formaterialsthatarelocallyreacting,thatis,withoutsoundpropagationinsidethematerialparalleltoitssurface,statisticalabsorptioncoefficientscanbeestimatedfromspecificnormalacousticimpedancevaluesusinganexpressionderivedbyLondon(1).5Locallyreactingmaterialsincludethosewithhighinternallossesparallelwiththesurfacesuchasporousorfibrousmaterialsofhighdensityormaterialsthatarebackedbypartitionedcavitiessuchasahoneycombcore.Formulasforestimatingrandomincidencesoundabsorptionpropertiesforbothlocallyandbulk-reactingmaterials,aswellasformultilayersystemswithandwithoutairspaceshavealsobeendeveloped(2).1.1Thistestmethodcoverstheuseofanimpedancetube,alternativelycalledastandingwaveapparatus,forthemeasurementofimpedanceratiosandthenormalincidencesoundabsorptioncoefficientsofacousticalmaterials.1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.1.3ThevaluesstatedinSIunitsaretoberegardedasthestandard.
【中国标准分类号】:Q25
【国际标准分类号】:91_120_20
【页数】:9P.;A4
【正文语种】: