排序方式: 共有42条查询结果,搜索用时 15 毫秒
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测量结果溯源是实现医学实验室标准化最重要的策略,旨在保证不同实验室、不同测量方法、不同型号、不同仪器厂家检测结果的准确可比。参考测量程序用于评价其他测量程序获得的同类被测量值的正确度。同位素稀释质谱法(isotope dilution mass spectrometry, IDMS)是具有高计量学特性的基准方法。本文主要对同位素稀释质谱法在临床参考系统中的应用进行综述,介绍基本原理、定量方式及其不确定度,并结合国际检验医学溯源联合会(joint committee for traceability in laboratory medicine, JCTLM)参考系统数据库,分析同位素稀释质谱法在临床参考系统的应用及最新进展,为临床参考系统、同位素应用以及计量相关工作者提供参考。 相似文献
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以双酚A高纯物质为目标物,采用库仑法水分滴定仪和控温、控湿型手套箱,考察卡尔·费休库仑滴定法准确测量高纯双酚A中痕量水分杂质过程中条件及环境等因素的影响,以提高有机高纯物质质量平衡法定值水平,降低水分杂质的不确定度分量。研究结果表明,实验条件下环境湿度对痕量水分杂质的定量具有显著影响。环境湿度会导致仪器漂移升高,空白响应增大;还会引起被测样品水分含量的变化。实验也考察了样品质量、搅拌时间等参数的影响。当样品质量较小时,测量结果明显偏高,随着样品质量的增大,滴定时间随之增加,测量结果趋于稳定;搅拌时间对测量结果没有显著影响。实验中使用固体水分含量标准物质对实验方法进行确证,实验结果稳定在其不确定度范围内。 相似文献
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全灿 《中国化学工程学报》2009,17(2):344-349
Based on the solubility in supercritical CO2, two strategies in which CO2 plays different roles are used to make quercetine and astaxanthin particles by supercritical fluid technologies. The experimental results showed that micronized quercetine particles with mean particle size of 1.0-1.5 µm can be made via solution enhanced dis-persion by supercritical fluids (SEDS) process, in which CO2 worked as turbulent anti-solvent; while for astaxan-thin, micronized particles with mean particle size of 0.3-0.8 µm were also made successfully by rapid expansion supercritical solution (RESS) process. 相似文献
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A very simple and direct method for determination of creatinine in serum based on high performance liquid chromatography and isotope dilution mass spectrometry (LC-ID/MS) is described. Chromatographic separations were performed with a zorbax bonusRP column. With a chromatographic run time of less than 10 min and sample preparation consisting of a simple protein precipitation, without the need for a derivatisation step, the analysis is greatly simpler than the conventional GC-IDMS method. 相似文献
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The feasibility of removal of the organochlorine pesticides residues of hexachlorocyclohexane(BHC)from radix ginseng with supercritical CO2 was explored. Some factors, such as extraction pressure, extraction temperature, and kinds of co-solvents were investigated. The experimental results indicate that it is possible to reduce BHC residues in radix ginseng to the level of 0.1 × 10-6 with supercritical CO2 in the presence of suitable amount of co-solvent, such as water. 相似文献
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通过定性分析、定量分析、均匀性检验、稳定性考察和不确定度评定,研制了叶酸纯度标准物质。其中采用质量平衡法(包括液相色谱法、水分、灰分、挥发性物质和无机元素分析)与定量核磁共振法对叶酸纯度标准物质进行了定量分析。叶酸纯品容易含有结晶水和吸附水,所以通常其主要杂质就是水分,而且叶酸受热易分解,所以难以除去水分。使用卡尔费休法和元素分析,准确测定了水分含量(8.48%)。叶酸的定值结果为90.6%,扩展不确定度为1.1%。对于实际检验中叶酸的准确测定及相关疾病的正确诊断治疗具有重要意义。 相似文献
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