工业电雷管国标与国外先进标准的比较

文章通过工业电雷管国标与国外先进标准在电性能、爆炸性能、安全性、抗水性、脚线的性能和检验规则等几个方面的比较,找出了现行国标的差距和不足,对国标技术指标的修改进行了探讨.     

我国钻石分级标准及钻石珠宝检测机构

2010版钻石分级标准 现在我国钻石分级执行的是国标GB／3、16554—2010,新国标规定了天然的未镶嵌抛光钻石的术语和定义,钻石颜色、     

航空铝合金防腐保护研究进展

对铬酸盐使用的严格限制促使人们探寻航空用铝合金环境友好防腐保护方法,它们分别是低温阳离子气相沉积、Sol-gel、陶瓷聚合物涂层、各种无机或有机缓蚀剂和双螺旋结构的导电聚合物,其中最有效的工艺方法是Sol-gel自组装有机-无机纳米颗粒涂层技术.综述了这些方面的研究工作.     

铝和铝合金表面涂层溶液的组成及其应用

一、概述铝和铝合金表面涂层溶液,主要是指能在金属表面形成化学转换膜,用以保护基体或作为后处理底层的溶液。它是一种只含磷酸盐的处理液,80年代初美国(Amchem公司)以“Alodine 404”商品作了报道,所以被称之为Alodine溶液,用这种溶液进行表面处理的方法,称之为Alodine方法。     

高效液相检测盐酸克伦特罗（瘦肉精）方法改进

本方法通过采用不同于国标GB/T5009.192-2003第二法的流动相和样品前处理技术检测动物性食品中盐酸克伦特罗（瘦肉精）,获得了高于国标的检出限和收回率。同时避免了复杂的样品前处理,有效提高了检样结果准确度。     

水表产品标准关键性能指标的分析与探讨

水表产品国家标准的正式发布与实施,给水表行业技术进步提出了新的要求与目标.通过对标准中部分修订及补充的关键性能指标的介绍与评述、对产品性能有关重要技术问题开展的探索与研究,可以为水表企业更好地理解新国标的基本要求及标准贯彻实施中的重点与难点,提供了可借鉴的方法和途径.     

熔丝法测定钯点计算方法的改进研究

本文介绍了一种用熔丝法测钯熔点时,计算钯熔化点的新方法.通过讨论钯熔化时时间与温度之间的理想数学模型,结合GB/T 18036-2000中使用的方法,提出了作者的一些看法.国标中所使用的方法采集的数据点少,对每个点的要求和依赖程度高,难以反映整个熔化过程的数值特征.且国标中对于熔化判定的标准显得生硬,故对于数据跳变没有很好的抵抗性.作者提出了处理数据时的一种新方法,可以有效的利用熔化前后的数据段以及熔化过程中的全部数据,对于熔化平台的判定有更强的抗干扰性.该方法能够广泛应用于计算其他金属的熔点的过程中,具有较高的普遍性.     

铝合金表面氧化锆等离子体电解氧化涂层的制备及形成机理研究

采用等离子体电解氧化方法在铝合金表面制备了氧化锆涂层,电解液为包含Zr(OH)₄颗粒的碱性溶液. 涂层的组成、结构通过XRD、EPMA进行了研究. 结果显示,涂层主要由t-ZrO₂、m-ZrO₂、α-Al₂O₃和γ-Al₂O₃组成,t-ZrO₂为涂层的主晶相,分布在涂层表面,而α-Al₂O₃出现在涂层的内侧.涂层表面呈颗粒状,颗粒尺寸约为1~2μm.在氧化过程中,Zr(OH)₄颗粒在电场力的作用下向等离子体放电通道口沉积,在放电产生的高温作用下直接转化为氧化锆.     

国标、ASTM标准及JIS标准对几种典型钢铁产品金相检验项目要求的对比分析

以碳素结构钢、合金结构钢、轴承钢、弹簧钢和冷作模具钢为例,将国标与美国ASTM标准和日本JIS标准对金相检验项目的要求进行了对比和分析.结果表明:国标对于金相检验项目的要求是最多的;ASTM标准对金相检验项目的要求较少但是具有针对性;JIS标准对金相检验项目的要求弹性较大,主要由买方与制造方协议规定.对比国外标准对应钢...     

新型无取向硅钢绝缘涂层附着性评定方法

常规的涂层附着性测量方法简单易行,但测量过程主观性强,数据不够客观,数值划分不够细化。介绍了一种结合弯辊国标法,以光泽度仪为测量平台的测量方法,该方法成本低、客观准确,细化后的附着性评定标准对现场工艺指导价值更高。     

强碰撞中型冲击机冲击环境特征

强碰撞中型冲击机是GJB150.18-1986规定的标准考核设施之一,它主要对于质量介于120 kg～2.7 t的舰船设备进行冲击考核,用于评定舰船设备的抗冲击能力 [1]。美国的中型冲击机经过大量的冲击环境试验,经过总结制定MIL-S-901系列中的标准考核工况,我国的中型冲击机仿照美国来设计,考核标准也参照美国标准来制定,但我国中型冲击机的冲击环境特征是什么,影响冲击环境的因素是什么,现有标准存在的问题是什么还不是十分清楚。针对这些问题给出我国中型冲击机应满足的冲击环境要求,提出我国舰船设备抗冲击考核标准的改进建议。     

基于重量稀释法的海水盐度测量标准不确定度研究

对基于重量稀释法的海水盐度测量标准进行了全面的不确定度分析研究,特别是对质量与盐度的传递关系,详细分析了过程引入的分量,为完善盐度标准量值溯源及传递体系,提供了技术参考。结果表明,基于重量稀释法配制的标准海水样品在盐度2～35范围内,其最大扩展不确定度与中国一级标准海水相当;并以8400B型实验室盐度计为被测对象,对配制的标准海水样品进行验证,测量结果完全满足盐度标准装置的性能要求。     

室内环境质量标准研究

针对我国现行室内环境质量相关标准已经不能满足人们对室内环境质量的要求,该文综合考虑了影响室内环境质量的化学性、生物性、辐射、声、光、室内用水等因素,提出更为科学合理的室内环境质量标准,包括6大污染类别,共计185项指标,为保障室内环境更加健康、安全、舒适提供技术支撑。     

Novel search algorithms for a mid-infrared spectral library of cotton contaminants

During harvest, a variety of plant based contaminants are collected along with cotton lint. The USDA previously created a mid-infrared, attenuated total reflection (ATR), Fourier transform infrared (FT-IR) spectral library of cotton contaminants for contaminant identification as the contaminants have negative impacts on yarn quality. This library has shown impressive identification rates for extremely similar cellulose based contaminants in cases where the library was representative of the samples searched. When spectra of contaminant samples from crops grown in different geographic locations, seasons, and conditions and measured with a different spectrometer and accessories were searched, identification rates for standard search algorithms decreased significantly. Six standard algorithms were examined: dot product, correlation, sum of absolute values of differences, sum of the square root of the absolute values of differences, sum of absolute values of differences of derivatives, and sum of squared differences of derivatives. Four categories of contaminants derived from cotton plants were considered: leaf, stem, seed coat, and hull. Experiments revealed that the performance of the standard search algorithms depended upon the category of sample being searched and that different algorithms provided complementary information about sample identity. These results indicated that choosing a single standard algorithm to search the library was not possible. Three voting scheme algorithms based on result frequency, result rank, category frequency, or a combination of these factors for the results returned by the standard algorithms were developed and tested for their capability to overcome the unpredictability of the standard algorithms' performances. The group voting scheme search was based on the number of spectra from each category of samples represented in the library returned in the top ten results of the standard algorithms. This group algorithm was able to identify correctly as many test spectra as the best standard algorithm without relying on human choice to select a standard algorithm to perform the searches.     

Attention Deficit Hyperactivity Disorder: scaling and standard setting using Rasch measurement

This paper explores the dimensionality of responses to the Adult Behavior Checklist Revised, a screening assessment for Attention Deficit Hyperactivity Disorder (ADHD) in college students, and demonstrates a standard setting process for diagnostic rating scales. Responses from 317 undergraduate college students were used to investigate dimensionality; 8 judges were used for the standard setting procedure. A series of Rasch rating scale analyses support the interpretation of Inattention and Impulsivity/Hyperactivity variables. Principal component analyses of residuals identified the existence of secondary variables that may have clinical implications for the evaluation and treatment of ADHD. For the standard setting process, judges generally displayed less variability than expected by the model. Several judges were in disagreement as to the level of symptomatology needed to indicate potential ADHD. The derived standard for Inattention was found to be more stringent than a previously suggested standard while the derived standard for Hyperactive/Impulsive more lenient. Prevalence rates found a diagnosis of Hyperactive/Impulsive to be more common than a diagnosis of Inattention. Efficient screening assessments for ADHD in college students are needed in order to determine who may qualify for further evaluation and special services. The standard setting process attempts to identify judge disagreement regarding the level of symptomatology (the standard) needed to qualify for additional evaluation and identify judge response strings not consistent with the item difficulties. Recommendations suggesting additional work on the screening assessment and standard setting process are outlined.     

基于可靠度理论的中小跨径桥梁卡车载重限值研究

卡车载重限值标准直接影响实际汽车荷载水平及其分布特性以及桥梁等基础设施的服役性能。为分析中小跨径桥梁的卡车载重限值问题,该文首先基于可靠度理论建立卡车载重限值分析模型;其次,基于长期记录的WIM（Weigh in Motion）数据分析我国典型公路路段卡车荷载特性并确定需要进行载重限值研究的重载卡车车型,并根据我国当前中小跨径桥梁建设现状选择对卡车载重限值起控制作用的桥梁结构类型;最后,建立结构关键截面抗弯功能函数,选择多层次目标可靠指标,对各类型卡车的载重限值进行反向迭代分析,基于分析结果分别讨论目标可靠指标、区域荷载特性对卡车载重限值的影响,以及现行公路治超标准对中小跨径桥梁车辆限载的适用性。分析结果显示:各类型卡车载重限值随着目标可靠指标的增大有明显线性下降趋势;区域卡车荷载特性的差异对卡车载重限值有着不可忽略的影响;现行国家治超标准对中小跨径桥梁车辆限载具有较好的适用性,但建议各地区根据自身实际情况在国家公路治超标准的基础上进行微调。     

出口包装用瓦楞纸箱抗压力合格评定方法的探讨

论述了在我国目前的国家标准及检验检疫行业标准中,出口包装用瓦楞纸箱的抗压力标准限值确定与评定中存在的问题及其改进的必要性,研究出了一种G0-法评定的全新方法,并介绍了其基本原理,分析了实施G0-法评定的具体方法及其可行性,并提出了在相关国家标准和检验检疫行业标准中对相关内容的修改建议。     

Failure Analysis of Shock Absorption Spring in Motorcycle

In the process development of a new spring for shock absorption in motorcycles, fatigue resistance cannot always reach the design standard. Spring fractures were sent to the author for failure analysis to identify reason behind and proposals for improvements were expected. Based on information from the spring manufacturer and spring fracture analysis, the reason for earlier breakage than design standard was determined to be process flaws. More specifically insufficient shot peening and embrittlement induced from electroplating were observed. This has been demonstrated by experimental results from an uncoated spring. A process optimization was proposed, and now, spring fatigue life has reached the design standard with the optimized process.     

Optimization of Direct Compression Tablet Formulations for Use in Tropical Countries

With the aid of a combined mixture- and factorial- design, 2 standard tablet formulations were selected suitable for use in tropical countries. The formulations were based on native ingredients or ingredients that are available worldwide. The selection of the standard formulations was based on both the initial tablet properties of the formulations one day after preparation as well as the physical stability after storage under tropical conditions.

The selected formulations were evaluated by adding model drugs (diazepam, 2 mg per tablet or hydrochlorthiazide, 100 mg per tablet) and measuring tablet properties, not only one day after preparation, but also after storage under tropical conditions. Both selected tablet formulations were suitable standard formulations for tablets prepared by direct compression for use in tropical countries.     

《快递包装重金属与特定物质限量》标准解读

目的 重点研究《快递包装重金属与特定物质限量》标准中有毒有害的环保指标的来源和检测方法,并介绍制定这一标准的背景。方法 基于SCQA（背景—问题—疑问—答案）的逻辑思路,梳理标准制定的过程,总结快递包装涉及的材质类型,按材质类型理清每种材质的环保限值指标,并给出标准发布实施的思考建议。结论 作为首个邮政寄递业的国家强制性标准,《快递包装重金属与特定物质限量》标准规定了快递包装用纸类、塑料类和纺织纤维类包装产品中重金属与特定物质限量的底线要求和红线要求,并描述了相应环保指标的试验方法,明确了快递封装用品的绿色环保指标和限量值,要求快递包装绿色无害化发展。