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A STUDY ON THE SAMPLE PREPARATION TECHNIQUES TO IMPROVE VARIATION ANALYSIS OF HYDROGEN AND CARBON ISOTOPES IN ENVIRONMENT

改进环境中氢和碳同位素变化分析的样品制备技术研究

基本信息

批准号：
13680609
负责人：
MURANAKA Takeshi
金额：
$ 1.28万
依托单位：
Hachinohe Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

We studied sample preparation techniques to develop variation analysis of hydrogen and carbon isotopes in environment. Obtained results are as follows.1. To measure low tritium concentration in environmental water samples, it is indispensables to enrich them by electrolysis. We enriched water samples connected a sample cell and a standard cell in series and calculated tritium concentration of the sample measuring an apparatus constant k or a recovery factor R in the standard cell as well as tritium concentration after electrolysis and so on in the sample cell. It was demonstrated that these two methods were equally effective to estimate tritium concentration in environmental water samples. This result has been reported in 6th international conference on tritium science and technology, held at Tsukuba, 2001.2. Since it takes much time for chemical preparation of ^<14>C samples, only two samples can be prepared in one week by a conventional process. We therefore divided the chemical proc … More ess into three divisions such as a device to activate vanadium catalysis, an electric furnace to form lithium carbide and acetylene-benzene preparation apparatus. As the result, we could have an ability of preparing four ^<14>C samples in a week, if we operate the three processes simultaneously.3. Recently it is desirable for ^<14>C ages to correct the fractionation effect of carbon isotopes and also to calibrate them to calendar year. We reported some examples applied to charcoal samples on the bulletin of Hachinohe Institute of Technology, Vol. 21, 2002.4. We investigate ^<14>C concentration in the leaves of Dandelion growing in some locations of Hachinohe area where traffic circumstances are differ from one another and confirmed that ^<14>C concentrations of Dandelion correspond to the local traffic conditions.5. We studied hydrogen stable isotope ratio, δD in every precipitation samples collected on the campus in Hachinohe Institute of Technology from Jan. 2000 to Dec. 2001. We found the seasonal variation of δD and interpreted the variation by three factors, that is, temperature effect of "yamase" and the growing location of precipitation. Less

为开展环境中氢碳同位素变异分析，对样品制备技术进行了研究。主要研究结果如下：1.电解法富集环境水样中的低浓度氚是测定环境水样中低浓度氚的必要手段。将样品池和标准池串联富集水样，通过测量标准池中的仪器常数k或回收因子R，以及样品池中电解后的氚浓度等，计算样品中的氚浓度。结果表明，这两种方法对环境水样中氚浓度的测定同样有效。2001年2月在筑波召开的第六届国际氚科学与技术会议上报告了这一结果。由于14C样品的化学制备需要很多时间<14>，因此通过常规方法在一周内只能制备两个样品。因此，我们将化学过程 ...更多信息该系统分为钒催化活化装置、碳化锂电炉和乙炔苯制备装置三大部分。因此，<14>如果我们将这三个过程操作得很好，我们可以在一周内制备四个^ C样品。近年来，人们希望^<14>C年龄能够校正碳同位素分馏效应，并将其校准到日历年。我们在八户工业大学学报2002.4第21卷上报道了一些应用于木炭样品的例子。我们调查了八户地区<14>交通状况不同的一些地方的丹顶鹤叶片中的^ C浓度，并确认丹顶鹤的^<14>C浓度与当地的交通状况相对应。对2000年1月至2001年12月在八户工业大学校园内采集的各种降水样品进行了氢稳定同位素比值δD的研究。发现了δD的季节变化，并从“山濑”温度效应和降水增长位置3个方面对δD的季节变化进行了解释。少