浅述空间转角弯管的安装

弯管是水电站压力钢管的重要组成部分。空间转角弯管则是一种常见的弯转形式(特别是一些小型电站多用此类弯管)。笔者曾投稿于《水电站机电技术》杂志88年第三期,论述了空间转角(含复合角)弯管的计算放样。依据设计给定的水平投影角和侧视投影角计算出此类含复合角弯管的实际放     

探析色彩在多媒体课件中的应用

针对目前大多数多媒体课件由任课教师自行完成的现状,对课件设计中色彩与文字设计的一些基本技巧进行了归纳,通过对色彩的特性、色彩的形成和对比规律、色彩间的相互关系、色彩的视觉效果及心理联想等的描述来探讨多媒体课件界面色彩的设计原则。     

LC-ICP-MS联机技术与同位素稀释质谱法精确测定小麦粉中硒代蛋氨酸

The precise determination of selenomethionine (SeMet) in wheat flour has been performed by species specific isotope dilution mass spectrometric analysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS). A labeled ⁷⁶SeMet species-specific isotope enriched spike solution was used for these determinations. The experiment procedure included spiking, extraction, and a simultaneous separation and detection procedure. The method gave yield to good precision (＜2%). The accuracy of the method has been validated on the certified reference materials. The result obtained was in good agreement with the certified reference value. And this method was used to do the international comparison CCQM-K60.     

同位素稀释-液相/气相-电感耦合等离子体质谱联用等方法为鱼肉中甲基汞成分标准物质准确定值

The fish tissue certified reference material is designed and prepared mainly for evaluating the determining accuracy of methyl mercury in sea fish or other seafood, as well as for a quality control standard. The property value was certified by three different methods, including high performance liquid chromatographic -cold vapor atomic fluorescence spectrometry（HPLC-CVAFS）method and species specific isotope dilution mass spectrometric analysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS) or gas chromatography (GC-ICP-MS). The experiment included spiking, extraction, derivatization, separation and detection procedures. The ERM 464 tuna fish reference material was used as the analytical quality control standard. The results obtained from three different methods were in good agreement. And the statistic average values were used as certified values of methylmercury in the fish tissue CRM.     

棉花公检实验室水幕除尘设备的日常维护

水幕除尘技术和设备对于新疆各纤检实验室来说还是一个新鲜事物,设备维护人员对其结构和工作原理还处于一个不断熟悉和了解的过程,因此设备在日常使用和维护中也遇到了不少问题. 水幕除尘设备的日常维护保养与故障排除 1.水幕除尘主机外地面有少量水渗出.可能是由于水幕除尘设备主机风机转速过大,风机产生强大的气流将喷淋装置喷射出的水流甩到机体侧板,水从侧板缝隙流出.可通过改变风机转速解决,通常风机转速设置在70％～80％即可.     

原子荧光形态分析仪的计量特性探讨和需求分析

简要介绍了原子荧光形态分析仪的发展概况及其工作原理和构造.分析了原子荧光形态分析仪在实际工作中影响其性能的重点考核指标,并将该类仪器与液相色谱仪和原子荧光光度计分别从构造、原理及计量特性等方面进行了对比.结合目前原子荧光形态分析仪在各领域的使用情况,从用户角度出发提出了对计量的迫切需求.     

食品中无机成分检测通用技术

食品中无机元素对食品的安全性、营养效果影响巨大,其中铅、镉、铬、汞、锡等有毒有害元素影响人体健康,而铁、铜、锌、钙、硒等营养元素则对人类基体的代谢功能有益。无机分析是当前食品安全检测领域中重要的工作内容之一。提升食品安全实验室的检测能力,需要大力提高实验室无机分析的能力。总体而言,食品中无机成分组成复杂,食品基体也形式多样     

棉花仪器化公检实验室火灾隐患的预防和应急处理

国家自2004年开始仪器化棉花检验体制改革以来,至今已有10年。新疆是全国棉花的主要产区,2012年度全国仪器化棉花公检数量720．63万t,新疆专业纤检机构作为当地的棉花承检方2012年度仪器化棉花公证检验443万余t,约占全国棉花仪器化公检数量的61．5％。其棉花公证检验实验室的规模是由小到大,年检验量也是年年创出新高。     

本刊带您认识部分食品中违禁添加物

违禁色素:五颜六色的陷阱违禁添加的色素违禁添加的色素主要指苏丹红、罗丹明B、碱性橙、金黄粉等为代表的工业色素。工业色素主要是以苯、甲苯、萘等芳烃类化工产品为原料,经过磺化、硝化、卤化、偶氮化等一系列有机反应化合而成,广泛用于印染、皮革和林木业等工业领域。根据GB2760-2011《食品添加剂使用标准》的规定,工业色素是严禁作为食品添加剂使用的。     

激光烧蚀-电感耦合等离子体质谱法进行铜合金成分定量分析

Techniques for semiquantitative analysis of solid materials by laser ablation (LA) sample introduction - inductively coupled plasma mass spectrometry (ICP-MS) are investigated. A 213nm laser efficiently ablates copper alloys. Ablated particulate material is transported by gas flow into an Agilent 7500ce ICP-MS. Quantitative analysis is obtained by internal standardization on either a known analyte or the sample matrix signal. The copper alloy samples are prepared for solution analysis subsequently. The analysis results by LA introduction mode and solution introduction mode are discussed.