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- natural isotopic composition 天然同位素组成
- How could such a change in isotopic composition have come about? 同位素的组成有这样的变化，究竟是如何发生的？
- Had the Oklo deposit remained a closed system, the xenon accumulated during operation of its natural reactors would have preserved the normal isotopic composition produced by fission. 如果欧克陆矿床一直保持为封闭系统，其天然核反应堆运作时所累积的氙，会维持著与一般核分裂产物相同的同位素组成。
- It is important to avoid the use of uranium compounds of unspecified isotopic composition. 要避免使用那种非专用的同位素成份的铀化合物。
- Another mystery is the isotopic composition of xenon found in minerals from the Oklo uranium deposit in Gabon, Africa. 另一个令人费解的问题就是在非洲加蓬的奥克洛铀矿床的矿物中所发现的氙同位素组成。
- The whole-rock Pb isotopic composit ions of the North Dabie Complex(NDC),the South Dabie Complex(SDC)and the Cretaceous granites in the ea st Dabie Mountains are reported. 研究了大别山东部北大别变质杂岩、南大别变质杂岩和白垩纪花岗岩的全岩Pb同位素组成。
- Stable isotopic composition of fossil ostracode is used as an ideal proxy for paleo-lake sedimentary environments. 摘要介形虫化石壳体被认为是反映古湖泊沉积环境的理想对象。
- Title： Zircon age and Sr-Nd-Hf isotopic composition of migmatite in the eastern Tengchong block,western Yunnan. 关 键 词： 滇西地区;基底;混合岩;锆石年龄;
- Osmium isotopes in the natural isotopic mixture are separation by gas centrifuge technology. 对天然锇同位素进行了离心分离。
- The research also shows that there is not any change in the stable carbon isotopic composition in all these river systems caused by the quake. 本研究同时显示921地震并未对这些河川之稳定碳同位素组成造成影响。
- It quickly became clear, however, that the isotopic composition of meteorites differed not at all from that of the Earth itself. 然而事情很快清楚了，陨石中的同位素比例与地球自身没有什么不同。
- The isotopic composition of hydrogen and oxygen in heavy water are analyzed by using a high-resolution mass spectrometer. 摘要用高分辨率质谱计分析了重水中氢与氧的同位素组成；
- To analyze the isotopic composition of xenon requires a mass spectrometer, an instrument that can separate atoms according to their atomic weight. 要分析氙的同位素组成需要一台质谱仪，这是一种能将原子按照原子量分离的仪器。
- Abstract The isotopic composition of hydrogen and oxygen in heavy water are analyzed by using a high-resolution mass spectrometer. 摘要 用高分辨率质谱计分析了重水中氢与氧的同位素组成;
- Carbon isotopic composition of modern soil and paleosol as a response to vegetation change on the Chinese Loess Plateau. 黄土高原现代土壤和古土壤有机碳同位素对植被的响应","Liu, WG;Ning, YF;An, ZS;Wu, ZH;
- This article mainly studies the origin of ore-forming matter, by analyzing ores, strata and granites Pb isotopic composition. 本文通过对彩霞山铅锌矿床的矿石铅、岩浆岩石铅和围岩岩石铅的同位素组成分析，来探讨成矿物质的来源。
- Deuterium, a natural isotope of heay hydrogen, haing one proton and on neutron, whereas normal hydrogen has one proton and zero neutrons, could be used routinely. 重水中的天然同位素氘具有一个质子一个中子，它不同于正常的氢只有一个质子没有中子，可以常规应用。
- Natural isotopes, 7Be and 210 Pb,including their sources, sinks, and their principles of tracing the atmospheric transport process are briefly introduced in this paper. 文章介绍了大气中天然放射性核素铍 7(7Be)、铅 2 10 (2 10 Pb)源、汇特征以及示踪大气动力输送过程的一般原理。
- Residence time ,storage and storage coefficient of covered Karst water in Dachahe area of Pingliang are evaluated by natural isotope based on wellmixed model of water body. 应用天然同位素及水体的完全混合模型，计算了平凉大岔河隐伏岩溶地下水的滞留时间、含水层储水系数及储存量。
- The results show that hydrogen and oxygen isotopic composition can be analyzed in the same time by using high-resolution mass spectrometer,little sample is used and the r... 结果表明,高分辨率质谱法分析重水,可同时分析其中的氢同位素和氧同位素,并且用样量小,结果可靠。
