The non-reduction characteristics of thermal ion emission for six kinds of graphite with different source, purity and crystal structure and one high pure carbon powder were studied in this paper.the results show that ...The non-reduction characteristics of thermal ion emission for six kinds of graphite with different source, purity and crystal structure and one high pure carbon powder were studied in this paper.the results show that the efficacy of thermal ion emission of graphite is weakly relative to purity and size of graphite, while decided by crystal structure of graphite. The graphite with perfect crystal structure has high efficacy of thermal ion emission.展开更多
The variations in the isotopic compositions of chlorine in evaporation controlled saline lake brines were determined by using an improved procedure for precise measurement of chlorine isotopes based on Cs 2Cl + ion by...The variations in the isotopic compositions of chlorine in evaporation controlled saline lake brines were determined by using an improved procedure for precise measurement of chlorine isotopes based on Cs 2Cl + ion by thermal ionization mass spectrometry. The results showed that variation in δ 37 Cl values in these evaporation controlled brines are attributable to evaporation of brine accompanied by the deposition of saline minerals. The isotopic fractionation of chlorine between the deposited saline mineral and the co existing brine caused the variation of δ 37 Cl values in the brine. In general the isotopic fractionation of chlorine in nature indicates enrichment of 3 7Cl in the solid phase relative to 3 5Cl. The reverse isotopic fractionation of chlorine in which 3 5Cl is enriched in the solid phase, was observed to some extent during quick deposition under laboratory conditions as well as in nature. The mechanism of isotopic fractionation of chlorine during evaporation deposition was studied.展开更多
There are a variety of salt lakes in the Qaidam Basin, Qinghai, where the climate isvery dry. These lakes are all rich in saline mineral deposits and brine resources. They pro-vide a good condition for study of chlori...There are a variety of salt lakes in the Qaidam Basin, Qinghai, where the climate isvery dry. These lakes are all rich in saline mineral deposits and brine resources. They pro-vide a good condition for study of chlorine isotopic composition and of fractionation be-tween brine and saline mineral deposit. In this note, we preliminarily study the展开更多
文摘The non-reduction characteristics of thermal ion emission for six kinds of graphite with different source, purity and crystal structure and one high pure carbon powder were studied in this paper.the results show that the efficacy of thermal ion emission of graphite is weakly relative to purity and size of graphite, while decided by crystal structure of graphite. The graphite with perfect crystal structure has high efficacy of thermal ion emission.
文摘The variations in the isotopic compositions of chlorine in evaporation controlled saline lake brines were determined by using an improved procedure for precise measurement of chlorine isotopes based on Cs 2Cl + ion by thermal ionization mass spectrometry. The results showed that variation in δ 37 Cl values in these evaporation controlled brines are attributable to evaporation of brine accompanied by the deposition of saline minerals. The isotopic fractionation of chlorine between the deposited saline mineral and the co existing brine caused the variation of δ 37 Cl values in the brine. In general the isotopic fractionation of chlorine in nature indicates enrichment of 3 7Cl in the solid phase relative to 3 5Cl. The reverse isotopic fractionation of chlorine in which 3 5Cl is enriched in the solid phase, was observed to some extent during quick deposition under laboratory conditions as well as in nature. The mechanism of isotopic fractionation of chlorine during evaporation deposition was studied.
基金Project supported by the National Natural Science Foundation of China.
文摘There are a variety of salt lakes in the Qaidam Basin, Qinghai, where the climate isvery dry. These lakes are all rich in saline mineral deposits and brine resources. They pro-vide a good condition for study of chlorine isotopic composition and of fractionation be-tween brine and saline mineral deposit. In this note, we preliminarily study the
