SAE J2883 Laboratory Measurement of Random Incidence Sound Absorption Tests Using a Small Reverberation Room

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Product Code:SAE J2883
Title:Laboratory Measurement of Random Incidence Sound Absorption Tests Using a Small Reverberation Room
Issuing Committee:Acoustical Materials Committee
Scope: This SAE Recommended Practice describes a laboratory test procedure for measuring the random incidence sound absorption coefficient of a material in a small size reverberant sound field by measuring decay rates. Materials for absorption treatments may include homogeneous materials, nonhomogeneous materials, or a combination of homogeneous, nonhomogeneous, and/or inelastic impervious materials. These materials are commonly installed in transportation systems such as ground vehicles, marine products, and aircraft to reduce reverberant sound build-up and thus reduce the noise level in the environment by minimizing reflections off of hard surfaces. The test method described herein was developed also to describe a way to measure the absorption performance of a part or a sound package system that will relate to an application. to rank order materials for application on panels using general automotive steel but also may be applicable to other situations or conditions.The absorption performance for most materials and systems varies as a function of frequency. Accordingly, this test procedure includes provisions for measuring absorption over a frequency range found applicable to many transportation systems. Samples that are used typically in transportation industry are not thick enough to provide any significant absorptive properties below 250 Hz. Combining the size of the sample and the frequency range of interest for automotive and related applications, this test method has been developed for conducting measurements using a small reverberation room where the frequency range of interest would be from approximately 250 to 8000 Hz 1/3rd octave band frequency.
Rationale: This SAE Recommended Practice describes a laboratory test procedure for measuring the random incidence sound absorption coefficient of a material in a small size reverberant sound field by measuring decay rates. Materials for absorption treatments may include homogeneous materials, nonhomogeneous materials, or a combination of homogeneous, nonhomogeneous, and/or inelastic impervious materials. These materials are commonly installed in transportation systems such as ground vehicles, marine products, and aircraft to reduce reverberant sound build-up and thus reduce the noise level in the environment by minimizing reflections off of hard surfaces. The test method described herein was developed also to describe a way to measure the absorption performance of a part or a sound package system that will relate to an application. to rank order materials for application on panels using general automotive steel but also may be applicable to other situations or conditions.The absorption performance for most materials and systems varies as a function of frequency. Accordingly, this test procedure includes provisions for measuring absorption over a frequency range found applicable to many transportation systems. Samples that are used typically in transportation industry are not thick enough to provide any significant absorptive properties below 250 Hz. Combining the size of the sample and the frequency range of interest for automotive and related applications, this test method has been developed for conducting measurements using a small reverberation room where the frequency range of interest would be from approximately 250 to 8000 Hz 1/3rd octave band frequency.
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【英文标准名称】:Specification-Orthodonticwireandtapeanddentalligaturewire
【原文标准名称】:整牙线带及牙科用结扎线规范
【标准号】:BS3507-1976
【标准状态】:现行
【国别】:英国
【发布日期】:1976-04-30
【实施或试行日期】:1976-04-30
【发布单位】:英国标准学会(BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:缠绕试验;不锈钢;弯曲试验;金属线;正畸矫正器;窄条带材;牙科材料;奥氏体钢;试验设备;抗拉强度;抗拉试验;尺寸
【英文主题词】:bendtesting;tensilestrength;dimensions;dentalmaterials;wrappingtests;orthodonticappliances;tape;austeniticsteels;stainlesssteels;testequipment;wires;tensiletesting
【摘要】:Performance,compositionanddimensionalrequirements.Includesmulti-strandwires.
【中国标准分类号】:C33
【国际标准分类号】:11_060_10
【页数】:8P;A4
【正文语种】:英语


基本信息
标准名称:无公害食品莲藕生产技术规程
中标分类: 农业、林业 >> 经济作物 >> 瓜果、蔬菜种植与产品
ICS分类: 农业 >> 农业和林业 >> 植物栽培
发布部门:中华人民共和国农业部
发布日期:2004-01-07
实施日期:2004-03-01
首发日期:1900-01-01
作废日期:1900-01-01
提出单位:中华人民共和国农业部
起草单位:湖北省绿色食品管理办公室、武汉市蔬菜科学研究所
起草人:李秋洪、刘义满、柯卫东、李峰等
出版社:中国农业出版社
出版日期:2004-03-01
页数:8页
书号:16109.258
适用范围

本标准规定了无公害食品莲藕(浅水藕,Nelumbo mucifera gaertn)生产的产地环境、生产技术、病虫害防治、采收和生产档案。
本标准适用于无公害食品莲藕的生产。

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引用标准

GB 4285 农药安全使用标准
GB/T 8321(所有部分) 农药合理使用准则
NY/T 496 肥料合理使用准则 通则
NY 5010 无公害食品 蔬菜产地环境条件
NY 5294 无公害食品 设施蔬菜产地环境条件

所属分类: 农业 林业 经济作物 瓜果 蔬菜种植与产品 农业 农业和林业 植物栽培