标准物质对气相色谱仪测定天然气热值的影响研究

探讨了天然气标准物质对气相色谱仪测定天然气热值的影响。用3种不同组成的气体标准物质(高热值、中热值和低热值),针对每一台在线气相色谱或离线气相色谱,采用高热值气体标准物质校准后,测量中热值和低热值气体标准物质;然后再用中热值气体标准物质校准,测量高热值和低热值气体标准物质;最后用低热值标准物质校准,测量高热值和中热值气体标准物质。该实验可为天然气热值计量系统误差确定提供数据支持。     

天然气组分检测定性与定量方法的探讨

针对目前天然气组成分析的现状，通过实验验证GB13610-2003《天然气的组成分析气相色谱法》的两个不足，并提出相应的改进办法。     

天然气标准物质与能量计量

目前,天然气能量计量大多数采用间接测量方法,即天然气能量由流量计量、发热量计量和组成分析三部分构成。其中,天然气组成分析需要相应的模拟天然气标准物质支持。本实验室研制了模拟天然气标准物质,并就模拟天然气标准物质参加了实验室间比对。比对结果表明,模拟天然气标准物质的量值准确可靠。模拟天然气标准物质的理论热值和实测热值吻合。     

二氧化碳中总烃“零点”气的制备

论述了二氧化碳中总烃"零点"气体标准物质的制备,并以气相色谱法对其均匀性和稳定性进行考查,量值准确可靠,可满足目前国内市场总烃在线分析仪器校准的要求.     

气相色谱法测定车用汽油中苯含量的不确定度评定

通过分析气相色谱法测定车用汽油中苯含量的方法,对车用汽油中苯含量的测量不确定度进行了评定,不确定度主要来源于标准样品配置和测试时体积引入的不确定度、标准物质苯和内标物（4-甲基-2-戊酮）纯度以及气相色谱仪器本身和微量进样器引入的不确定度。     

氦氩混合气体的组成分析

针对目前没有氦氩混合气体产品质量标准的现状,采用气相色谱法对广泛应用的氦氩混合气体组成进行定量分析,并结合氦、氩气体的产品标准,通过不同的样品状态分析结果的影响,将气相色谱法作为混合气体质量控制方法的可能性进行讨论。     

组成分析对混输天然气的能量计量影响探讨

针对天然气混输管网格局的形成,分析能量计量的必要性。鉴于我国已经形成了成熟的体积计量体系,体积计量对天然气能量计量的影响不再考虑,主要分析天然气组成分析准确性对能量计量的影响,包括气相色谱仪性能、天然气标准物质、天然气组成赋值等方面。提出需要对在线气相色谱仪进行性能评价,制定混输气质变化大的天然气组成分析所用标准物质的相关规范,对于多气源气质变化显著的贸易交接点,不建议采取人工赋值的方法,建议安装在线气相色谱仪实时分析天然气组成实现能量计量。     

低浓度羰基硫气体标准物质的制备

叙述了低浓度羰基硫气体标准物质的制备方法,以火焰光度检测器气相色谱法对其稳定性、均匀性进行考察,并与同行的气体标准物质进行了比对分析,证明制备的标准气体数值准确可靠。     

甲醇纯度国家一级标准物质的研制

介绍了甲醇纯度标准物质的研制方法,采用国际基准方法之一的凝固点下降法对该标准物质进行了定值,利用气相色谱法对定值结果进行了验证,同时对该标准物质进行了均匀性检验和稳定性考察.甲醇纯度标准物质定值结果为99.7%,扩展不确定度为0.3%.其均匀性和稳定性检验结果表明,该标准物质符合国家一级标准物质的技术要求.     

食品级二氧化碳中乙醇含量气相色谱分析方法的研究

本实验采用气相色谱法分析二氧化碳中的痕量级组分气体--乙醇.主要影响因素有进样口温度、毛细柱温度、检测器温度、毛细柱流速、尾吹,对各项优化后测得精密度为0.6%,线性误差不大于±2%.该方法快速、准确,可应用于该标准物质的分析定值.     

用阵列测量技术对微米、亚微米单分散微球粒径定值

分析了微球阵列测量法的特征和应用情况,并采用该法对5种微米、亚微米单分散二氧化硅微球粒度标准物质进行了测量.其平均粒径可溯源到中国计量科学研究院标准长度.经与溯源至美国国家标准技术研究院标准长度的测量结果相对照,两个测量结果一致.证明微球阵列测量法可以应用到亚微米级单分散微球粒度标准物质的定值.     

Certified reference materials of trace elements in water

Measurement of trace elements is playing a vital role in industries and various sectors of science and technology including semiconductors, food, health and environmental sectors. In most of the cases a small error in measurement can vitiate all the measures taken for quality control and management. Many decisions regarding the suitability of material/products are based on the analysis. To reduce or eliminate the rejection rate of the products, accurate and reliable measurements are needed which can be achieved by the use of certified reference materials (CRMs). Their use in calibration of analytical equipments and validation of test methods ensures high quality in measurements and it provides traceability to the measurement data with national/international measurement systems (SI unit) also. In the present scenario of globalization of economy, use of certified reference materials (CRMs) in measurements is essential for global acceptance of products and test reports. Their use fulfil a mandatory requirement of international quality systems (ISO 9000, ISO/IEC standard 17025) including our national accreditation body, National Accreditation Board for Testing and Calibration Laboratories (NABL), World Trade Organization (WTO) etc. International manufacturers of CRMs are meeting most of the requirement of CRMs of the country. To meet the demand of CRMs indigenously, the National Physical Laboratory, India initiated a national programme on preparation and dissemination of certified reference materials.     

250Hz～8kHz频率范围水听器自由场校准补充比对

介绍了以杭州应用声学研究所作为主导实验室与俄罗斯国立物理技术和无线电工程测量研究院开展COOMET.AUV.W-S1:250 Hz~8 kHz频率范围水听器自由场校准国际补充比对的结果。比对校准了两只标准水听器TC 4033和GI 55。互易法和比较法及其校准装置被用于评估中俄两国在水听器自由场低频校准方面的当前水平。结果显示,中俄两国得到的两只标准水听器的自由场灵敏度校准结果具有很好的一致性,绝大多数频率点的校准结果与参考值的差值小于0.40 dB,最大偏差为0.59 dB。结果证明,中俄两国的自由场水听器校准低限可扩展至250 Hz。     

Development, validation, and application of a method for quantification of methylmercury in biological marine materials using gas chromatography atomic emission detection

A gas chromatographic method was developed for the quantification of alkylmercury species using microwave-induced plasma atomic emission detection (GC-AED). The column conditioning and analyte derivatization required for previous methods were found to be unnecessary for stable, accurate, and sensitive element-specific detection using GC-AED. Chromatographic and detection parameters such as stationary phase type, stationary phase film thickness, GC column dimensions, helium mobile phase column head pressure, detector makeup gas flow rate, and detector reagent gas type and flow rate were found to significantly affect analyte response. The detection limit for the optimized GC-AED conditions was 0.8 pg (0.1 pg/s) of methylmercury chloride (as mercury). A solid-liquid extraction procedure with preparative gel permeation chromatography cleanup and GC-AED analysis was used to quantify methylmercury in a variety of complex matrix marine materials. The methylmercury quantification method was validated with four marine certified reference materials (CRMs). The method was then applied to 13 standard reference materials, CRMs, and control materials for which no certified reference values for methylmercury have been determined. Four National Institute of Standards and Technology Standard Reference Materials and one control material, which were analyzed using the GC-AED method, were also analyzed by two other laboratories using independent methods to further validate the method.     

A System's Mean Time To Repair Allocation Method Based on the Time Factors

The aim of the maintenance allocation is to allocate the maintenance time to the subsystems reasonably and accurately. Traditional mean time to repair (MTTR) allocation methods are widely used in the industry. However, there are many deficiencies in practical application, which is inconsistent with the purpose of the maintenance allocation. To allocate the MTTR more precisely and reasonably, a better model is needed. The aim of this paper is to develop a maintenance allocation model, which can improve the applicability and operability, and solve the residue problem that exists in maintenance allocation. A case study is used to demonstrate how the model can be applied in practice. Copyright © 2013 John Wiley & Sons, Ltd.     

食品添加剂二氧化碳中氧标准物质重量制备方法及重量制备不确定度的研究

研究了食品添加剂二氧化碳中氧标准物质重量制备的实验方法及不确定度评价研究的内容.采用中国计量科学研究院设计加工的气体充填装置制备了二氧化碳中氧标准物质,该装置低压系统真空度达到7×10-3Pa;气体称量装置采用美国Mettler SB16001电子天平(16 kg、0.1 g)和上海第二天平仪器厂TG320B高精密天平...     

Practice of Unconventional Gas Development and Engineering Management Innovation in China

This article analyses the recent progressive increase in resourcequantity and production quantity of unconventional natural gas in China, describes its natural properties and the concepts, strategies and approaches of its development, summarizes the special techniques, management concepts and development modes formed in the process of its development, and puts forward proposals to accelerate the development of unconventional natural gas of China. The technically recoverable reserve of unconventional natural gas is 1.7 times that of conventional natural gas and its output in 2012 accounted for 41.8% of the total output in China. Chinese tight gas development has gained success, coal-bed methane development and shale gas production pilots have made important progresses. As the key feature of unconventional natural gas is "low grade", for the effective scale development, developers must build up the engineering concept of low-grade resources development, adhere to the low cost strategy, take the development route of "a step backward and then a step forward", apply such ideas and methods of engineering management as low cost dualistic integrative innovation, full control network management, economic limit theory, integrated operation and "four orientations" engineering management, establish a "two lows" engineering management system, and take reference of the successful development mode of the tight gas in Sulige and the coal-bed methane in the Qinshui basin. In order to achieve the objective of rapid development of nonconventional natural gas in China and to accelerate the development pace, the government should continue to increase support, to speed up the reform of natural gas price adjustment, to set up national comprehensive development and utilization demonstration areas, to input in sustainable technological research and to promote engineering management innovation.?     

人血清中葡萄糖标准物质的研制

血糖是诊断和判别糖尿病的直接指标,标准物质是血糖检测结果准确可比的重要保障。研制人血清中6个不同浓度水平的葡萄糖标准物质的过程包括标准物质的制备、定值、均匀性、稳定性检验、不确定度评定以及互通性评价等内容。其中标准物质定值采用了两种不同原理的方法即同位素稀释-液相色谱-串联质谱法及同位素稀释-气相色谱-质谱法,准确测定人血清中葡萄糖的浓度,并重点分析了两种方法测试结果的差异及成因。人血清中葡萄糖标准物质的量值覆盖1.70～28.12 mmol/L,具有良好的均匀性和稳定性,已获得国家二级标准物质定级证书,编号为GBW(E)091140～GBW(E)091145,有望用于临床检验及相关领域对血清葡萄糖项目测量的质量评价等方面。     

国内多齿分度台比对

2007年度以华南国家计量测试中心为组织单位,以中国计量科学研究院为主导实验室,组织全国各大区和部分部委实验室之间首次进行了角度计量标准-多齿分度台的比对工作.本次比对样品的参考值由中国计量科学研究院提供.参加本次比对的实验室共有8家.通过对多齿分度台检定结果的比对分析,反映出各参比实验室在角度测试方面的综合能力及存在的问题.     

Standards for bullets and casings

The National Institute of Standards and Technology is developing reference standards through its Office of Law Enforcement Standards with funding provided by the National Institute of Justice. The standard reference materials are used by crime laboratories to verify that results obtained when using their protocols and methodologies meet legal requirements and that equipment is operating properly. The NIST Reference Materials 8240/8250 standard bullets and casings is an example of materials that will assist laboratories in calibrating their instruments and ensuring quality control.The Office of Law Enforcement Standards (OLES) at the National Institute of Standards and Technology (NIST) manages research in many different disciplines of forensic science. One of these projects supports the National Integrated Ballistics Information Network (NIBIN). NIST digitized six bullet signatures from samples provided by the Bureau of Alcohol, Tobacco, and Firearms (ATF) and the Federal Bureau of Investigation (FBI). Using these signatures as a virtual standard, NIST’s Instrument Shop manufactured 20 reference materials (RM) 8240 standard bullets using a numerically-controlled diamond turning machine. Test results show high reproducibility of the bullet signatures on standard bullets. NIST has also developed a new parameter for bullet signature comparisons, using autocorrelation functions, and proposed a diagram for tracing local ballistics measurements to the National Laboratory Center of the ATF and to the FBI. Using an electro-forming process, NIST has manufactured prototype standard casings and test results show high reproducibility for the casing signatures.