热表面电离质谱精确测定人体排泄物中锌同位素丰度比

In this work isotope mass spectrometry was adopted for the study of determination of zinc absorption by using a double label stable isotope technique. The methods of the sample digestion, separation and measurement of trace zinc by using thermal ionization mass spectrometer were established, and the isotopic ratios of zinc in the excrements and urine were measured accurately. The reliable zinc absorption was obtained from this.

质谱法测量碳同位素丰度在气体扩散法分离乙醇中的应用

乙醇是扩散分离碳同位素的一种可行的介质,为得到气体扩散法分离乙醇的分离系数,开展元素分析-同位素比质谱法(EA-IRMS)测量乙醇中碳同位素丰度在气体扩散分离实验中的应用研究。通过文献调研,本研究优化了乙醇样品的制备流程,发展了EA-IRMS用于乙醇碳同位素丰度测定的方法,进行了稳定性测试,实现了对乙醇样品碳同位素丰度的测量。基于气体扩散法的分离实验,获取多次分离实验中精料乙醇和贫料乙醇的碳同位素丰度,经公式推导可计算得到乙醇扩散分离碳同位素的基本全分离系数。本研究为未来开展以乙醇为介质扩散分离碳同位素实验提供了分析基础。

稳定VG354质谱仪磁场的技术创新及意义

This paper describes the method and way for the stable magnetism of VG354 mass spectrometer. Hall probe is fixed by technological innovation so that the magnetism can be stabilized . Sr and Nd isotopic ratio are mormalized to 86Sr/88Sr=0.1194 and 146Nd/144Nd =0.7219. The 87Sr/86Sr (NBS987)=0.710228±10(n=24).The 146Nd/144Nd (La Jolla) =0.511860±6(n=9).

尿素[13C]呼气试验诊断试剂盒中掺杂尿素的快速GC/MS检测

目的:建立尿素[13C]呼气试验诊断试剂盒中掺杂尿素的快速检测方法。方法:采用气相色谱-质谱联用法,色谱柱为Thermo TG-WAXMS A(15 m×0.25 mm×0.25μm),单四极杆EI离子源进行检测,选择离子扫描模式。结果:2%~50%的尿素加样测定理论值与实际值误差小于0.4%,3批实际样品经检测未添加普通尿素。该检测方法的定量下限为0.25 mg·mL-1,在0.1~1 mg·mL-1的线性范围内,尿素[13C]对照品的13C丰度均值为99.0%(n=6,RSD=0.090%)。结论:该方法操作简便快速、灵敏可靠,适用于尿素[13C]呼气试验诊断试剂盒中掺杂普通尿素的快速检测。