共查询到18条相似文献,搜索用时 187 毫秒
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本文介绍了氮中乙烷气体标准物质制备的原理和过程,运用气相色谱仪对该气体标准物质进行比较法定值,同时对研制气体标准物质的压力变化均匀性以及储存时间稳定性考察,以及对引入的不确定度进行计算评估.试验结果表明研制的气体标准物质量值准确可靠,在浓度范围内具备良好的均匀性和稳定性,技术指标达到了项目预期目标. 相似文献
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3月13日,由北京市计量检测科学研究院研制成功的“呼出气体酒精含量探测器”计量检定标准装置,通过了国家质检总局主持的鉴定。
据该项目负责人介绍,该装置集供气系统和多功能检测平台于一体,构成了一套完整的检测系统。该装置可同时产生三个不同浓度的酒精标准气体,其最大特点是可以大量地连续产生稳定的酒精标准气体,并且可以方便地改变给出气体的流量,满足对不同浓度标准气体检测的要求。 相似文献
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对医疗卫生用标准气体的研制及应用前景进行了探讨,给出了气相色谱分析的基本方法和条件并就标准气体的性能进行了评价。 相似文献
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M. Jaeschke A. Schmücker A. Pramann P. Ulbig 《International Journal of Thermophysics》2007,28(1):220-244
Natural gas plays an important role for worldwide energy supply. For billing purposes precise metering of volume and superior
calorific value are very important. At present, only a few institutions worldwide are able to determine the superior calorific
value (SCV) of gases and their mixtures with an uncertainty of less than 0.2%. Calculations of SCV’s of natural gases using
the data of ISO 6976 provides a similar uncertainty as experimental approaches. For this reason a GERG (Groupe Européen de
Recherches Gazières) project was initiated to develop a new reference calorimeter for determining the SCV of flammable gases
(natural gases), based on the principle of Rossini for a combustion calorimeter. The purpose of such a reference calorimeter
is to determine the SCV of pure gases and gas mixtures with an uncertainty of less than 0.05%. The overall uncertainty budget
for the SCV is mainly influenced by the mass determination and temperature measurement. An automated weighing and calibration
device is used to measure the mass of the combusted gas with an experimental uncertainty of approx. 0.015%. In addition to
the experiment, the flow and temperature field in the calorimeter were simulated. These simulations help to reduce each of
the combined uncertainties for the combustion and calibration experiment resulting from the temperature measurement. The determination
of the adiabatic temperature rise is performed analytically. The assumptions made by early investigators were carefully reconsidered
for the first time. The analysis of the temperature–time curves considers (a) the method of evaluation, (b) the interval length
of the main period, (c) the location of the heat release during the calibration experiment, and (d) the temperature sensor
location. 相似文献
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茶叶中啶虫脒残留量检测方法的研究 总被引:7,自引:0,他引:7
建立了啶虫脒在茶叶中残留量的气相色谱检测方法。样品采用丙酮/正已烷(1/2,v/v)混合溶剂提取,经LC-18SPE小柱净化,气相色谱(配ECD)检测,以保留时间和外标法定性、定量。结果表明,该方法的最低检出限为0.004mg/kg,不同水平的加标回收率范围为73.8%~108.7%,RSD(n=6)为8.51%~10.1%。方法操作简便,净化效果理想,能满足残留分析的要求,可用于茶叶啶虫脒残留量的测定。该方法也可为其他产品中啶虫脒残留量的测定提供参考。 相似文献
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极高真空校准室内残余气体的成分分析 总被引:3,自引:2,他引:1
用四极质谱计对316L不锈钢制作的极高真空(XHV)校准室在烘烤前、后的残余气体成分进行了分析。一个热阴极电离规(IE514)和一个四极质谱计(QMS200)连接在XHV校准室上。烘烤前,开、关热阴极电离规以及对其进行除气,放出的气体主要有H2O、CO、H2、CH4和CO2。烘烤后,开、关热阴极电离规以及对其进行除气,放出的气体主要有CO、H2、CO2和CH4。整个烘烤过程完成后2h,XHV校准室内的压力在室温下通过分子泵串联抽气机组抽至8.97×10-9Pa,用四极质谱计分析到的残余气体成分主要为H2和CO。整个烘烤过程完成后4h,打开非蒸散型吸气剂泵(NEGP)对XHV校准室抽气,结果表明NEGP对H2具有较大的抽速,但对碳氢类化合物(如CH4)和惰性气体几乎没有抽速。用NEGP对XHV校准室连续抽气72h后,XHV校准室内的压力从8.34×10-9Pa下降到9.12×10-10Pa。不锈钢XHV校准室内的残余气体成分中大量的CO和CO2主要来自于四极质谱计。 相似文献