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- A method by cumulative intensity of ion current to analyse isotopic ratio is proposed in present paper. 本文介绍了离子流强度累计测定同位素比的方法。
- The isotopic ratio of lithium was determined by cumulating intensity of ion current during evaporation of all samples on evaporation filament. 用热表面离子源测定了锂同位素丰度,在样品全耗尽过程中累计离子流强度。
- The isotope ratio is directly used for comparing oils or gases. 同位素比率直接用于比较各种石油或天然气。
- The atmospheric helium isotope ratio: Is it changing? 大气氦同位素比率在变化吗?
- Precise determination of the platinum-group elements and Os isotopic ratios in low-level rock samples. 岩石样品中低含量铂族元素和锇同位素比值的高精度测量方法。
- SNIF-NMR and IRMS methods were used to determine the stable isotopic ratios of D/H and 18O/16O of wine. 摘要利用SNIF-NMR和IRMS技术测定葡萄酒中稳定性同位素D/H和18O/16O的比值。
- Isotopic ratio in Mars atmosphere 火星大气的同位素比值
- They compared the hydrogen and oxygen isotopic ratios in the hair with tap water from each location, and found that they matched. 比对来自每一处毛发中自来水留下的氢及氧的同位素比率，发现比率是匹配的。
- Nd isotopic ratios of K-enriched magmatic complexes from southeastern Guangxi province: Implications for upwelling of the mantle in southeastern China during the Mesozoic. 桂东南富钾岩浆杂岩的Nd同位素组成:华南中生代地幔物质上涌事件。
- Stable isotope ratio analysis is an effective method for the identification of fruit juice adulteration. 稳定同位素分析法就是根据这种差异对掺假果汁进行准确鉴别的有效方法。
- The stable isotopic research is established by studying the discrepancy in isotope ratio, which was caused by isotope fractionation, and the isotopic ratio difference can be determined by mass spectrometer. 稳定同位素的研究主要是建立在此同位素分化作用所造成的同位素比值差异，而此同位素比值差异可被质谱仪测知。
- There are differences between natural and adulterated juices in stable isotope ratio. 天然果汁与掺假果汁之间在稳定同位素比率方面存在着差异。
- Although the products have same chemical compositions, they will exhibit various isotopic ratios if they produced from different sources or by different chemical/physical processes. 虽然物质具相同之化学组成，但如果来源不同或经不同物理／化学过程所产生，其同位素比值会因同位素的分化作用而有差异。
- Analysis on the Isotopic Ratio of Picogram Pu by TIMS 皮克量级钚同位素丰度比的TIMS分析
- To be sure, some scientists suggest that life could have evolved differently on Titan than on Earth or that the inorganic isotope ratio may be different there. 不过，还是有些科学家指出，可能是泰坦和地球上的生命演化过程不同，或是无机同位素比率不一样。
- Analytical services include potassium-argon age determinations, stable isotope ratio analyses, radiocarbon age determinations as well as other radiometric analyses. 分析包括钾-氩测年，稳定同位素丰度分析，放射性碳测年，以及其他放射性分析。
- Study on Carbon Isotopic Ratio of Individual Compound in Hopanes 生物标志物藿烷类的单体碳稳定同位素研究
- Accurate Determination of Isotopic Ratio and Abundance of Nitrogen 氮同位素丰度及其比值的准确测定
- An obvious restraint in the use of isotope ratios results from the need to employ mass spectrometers. 使用同位素比值法有着一个明显的局限因素，就是要用质谱仪进行分析。
- The ratio of students to teachers is 35:1. 学生和老师的比率是三十五比一。
