IEEE 444-1973 半导体闸流管换流器与电动机驱动器实用规程与要求-第1部分:直流电动机电枢电源换流器

上一篇: IEC 60424-1973 磁性氧化物元件物理缺陷极限规范的导则
下一篇: JIS C5574-1973 录像带用磁带盘

Product Code:SAE J2846
Title:Laboratory Measurement of the Acoustical Performance of Body Cavity Filler Materials
Issuing Committee:Acoustical Materials Committee
Scope:This SAE Recommended Practice describes a laboratory test procedure for measuring the acoustical performance of a system consisting of a body cavity filler material formed into a rectangular cross-section channel. Materials for this test may include both heat reactive and chemically reactive products, with or without a nylon or other shelf to simulate a baffle in an application, or a combination of body cavity filler and aluminum foil to enhance the performance. These materials are commonly installed in transportation systems such as ground vehicles, and thus reduce the noise propagation through the rails, rockers, and pillar/posts. This document is intended to rank order the acoustical performance of materials for application on channels using general automotive steel, such that the effects of sealing of pinch welds in addition to the material could be easily evaluated. The acoustical performance is expressed in terms of insertion loss (IL) which is described below. The test procedure described here is based on the method described in SAE J1400. However, this document differs from the SAE J1400 method in that the J1400 measures sound transmission loss, and this document measures IL of body cavity materials in a cavity.【英文标准名称】:StandardTestMethodforMajorityCarrierConcentrationinSemiconductorsbyMeasurementofWavenumberorWavelengthofthePlasmaResonanceMinimum
【原文标准名称】:通过测量等离子体共振的最小波数或波长测定半导体材料中多数载流子浓度的标准试验方法
【标准号】:ASTMF398-1992
【标准状态】:作废
【国别】:美国
【发布日期】:1992
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:ASTM
【标准类型】:()
【标准水平】:()
【中文主题词】:电子工程;等离子体;共振;浓缩;波长;大梁;半导体;试验;测量
【英文主题词】:resonance;testing;plasma;concentration;measurement;electronicengineering;semiconductors;wavelengths;girders
【摘要】:
【中国标准分类号】:H82
【国际标准分类号】:29_045
【页数】:10P;A4
【正文语种】:英语