| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2002: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 2001: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
|---|
| Research Abstract |
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
|
