In this paper, the determination and analysis of oxygen and carbon isotopes were carried out on 155 core and 180 core respectively. These data provides us with a fundamental understanding of the paleotemperature and p...In this paper, the determination and analysis of oxygen and carbon isotopes were carried out on 155 core and 180 core respectively. These data provides us with a fundamental understanding of the paleotemperature and paleoenvironmental evolution features and climate-stratigraphic classification of central Okinawa Trough since the late-glacial.展开更多
A new method for isotopic determination of N and O in nitrate based on CsNO2+ with graphite load by positive thermal ionization mass spectrometry is present. The new method has been applied to determine N and O isotop...A new method for isotopic determination of N and O in nitrate based on CsNO2+ with graphite load by positive thermal ionization mass spectrometry is present. The new method has been applied to determine N and O isotope in several nitrate reagents.展开更多
为了高效地从地质/环境样品中分离纯化Li元素并进行Li同位素测定,经反复实验和改良发现:采用8 m L容积(树脂体积)离子交换柱,选取AG 50W-X12阳离子交换树脂,以0.5 mol/L HNO3为淋洗液,过柱一次,并收集20~48 m L区间的淋洗液,即可一步实...为了高效地从地质/环境样品中分离纯化Li元素并进行Li同位素测定,经反复实验和改良发现:采用8 m L容积(树脂体积)离子交换柱,选取AG 50W-X12阳离子交换树脂,以0.5 mol/L HNO3为淋洗液,过柱一次,并收集20~48 m L区间的淋洗液,即可一步实现Li的完全纯化分离。对于高盐样品,建议过柱两次确保Na/Li<1,以达到上机测试的要求。由多种单元素标准混合的工作溶液(IEECAS-Li)经此流程分离后,采用Neptune Plus MC-ICP-MS测量得到的δ7Li值为8.31‰±0.12‰,与未混合的标准值(8.33‰±0.20‰)在误差范围内一致。采用此流程,获得的岩石标准物质AGV-2、BHVO-2和海水标准物质NASS-6的δ7Li值(2 s.d.,n=5)也与推荐值一致,分别为6.83‰±0.75‰、4.32‰±0.33‰和31.10‰±0.60‰。由此,我们建立了一套高效分离纯化Li及其同位素的MC-ICP-MS测试程序。将该程序用到Li含量在15 ng/g^90μg/g之间的实际样品中,δ7Li的长期内精度均好于0.30‰,且重现性高,表明该方法的分析精度和准确度都达到了国际标准水平。尤为重要的是,本方法可用于精确测量含痕量Li的环境样品的Li同位素组成。展开更多
独居石[（LREE，Th）PO4]分布广泛，是一种中酸性岩浆岩和变质岩中较常见的副矿物，在一些沉积岩中也存在。通常具有较高的Th、U含量和较低的普通铅组成，封闭温度高，在形成后的封闭体系中U／Th／Pb比值基本不受后期地质作用影响，是U...独居石[（LREE，Th）PO4]分布广泛，是一种中酸性岩浆岩和变质岩中较常见的副矿物，在一些沉积岩中也存在。通常具有较高的Th、U含量和较低的普通铅组成，封闭温度高，在形成后的封闭体系中U／Th／Pb比值基本不受后期地质作用影响，是U-Pb测年的理想对象（Parrish，1990：Paquette and Tiepolo，2007）。展开更多
A determination method for isotope ratios of iron in faeces samples is studied in this paper. The sample is decomposed in microwave oven by HNO3. A double focusing ICP-MS mass spectrometer (ELEMENT) working at resolut...A determination method for isotope ratios of iron in faeces samples is studied in this paper. The sample is decomposed in microwave oven by HNO3. A double focusing ICP-MS mass spectrometer (ELEMENT) working at resolution of 3000 allows the complete resolution of polyatomic ions overlapping. Instrumental parameters of the mass spectrometer are optimized for optimum precision. The RSD values obtained for the isotope ratios of 54Fe/56Fe, 57Fe/56Fe and 58Fe/56Fe are 0.23, 0.14, 0.22%, respectively, for a natural standard solution of 5ug/ml. The method has been used to iron nutrition studies.展开更多
文摘In this paper, the determination and analysis of oxygen and carbon isotopes were carried out on 155 core and 180 core respectively. These data provides us with a fundamental understanding of the paleotemperature and paleoenvironmental evolution features and climate-stratigraphic classification of central Okinawa Trough since the late-glacial.
文摘A new method for isotopic determination of N and O in nitrate based on CsNO2+ with graphite load by positive thermal ionization mass spectrometry is present. The new method has been applied to determine N and O isotope in several nitrate reagents.
文摘为了高效地从地质/环境样品中分离纯化Li元素并进行Li同位素测定,经反复实验和改良发现:采用8 m L容积(树脂体积)离子交换柱,选取AG 50W-X12阳离子交换树脂,以0.5 mol/L HNO3为淋洗液,过柱一次,并收集20~48 m L区间的淋洗液,即可一步实现Li的完全纯化分离。对于高盐样品,建议过柱两次确保Na/Li<1,以达到上机测试的要求。由多种单元素标准混合的工作溶液(IEECAS-Li)经此流程分离后,采用Neptune Plus MC-ICP-MS测量得到的δ7Li值为8.31‰±0.12‰,与未混合的标准值(8.33‰±0.20‰)在误差范围内一致。采用此流程,获得的岩石标准物质AGV-2、BHVO-2和海水标准物质NASS-6的δ7Li值(2 s.d.,n=5)也与推荐值一致,分别为6.83‰±0.75‰、4.32‰±0.33‰和31.10‰±0.60‰。由此,我们建立了一套高效分离纯化Li及其同位素的MC-ICP-MS测试程序。将该程序用到Li含量在15 ng/g^90μg/g之间的实际样品中,δ7Li的长期内精度均好于0.30‰,且重现性高,表明该方法的分析精度和准确度都达到了国际标准水平。尤为重要的是,本方法可用于精确测量含痕量Li的环境样品的Li同位素组成。
文摘独居石[（LREE，Th）PO4]分布广泛，是一种中酸性岩浆岩和变质岩中较常见的副矿物，在一些沉积岩中也存在。通常具有较高的Th、U含量和较低的普通铅组成，封闭温度高，在形成后的封闭体系中U／Th／Pb比值基本不受后期地质作用影响，是U-Pb测年的理想对象（Parrish，1990：Paquette and Tiepolo，2007）。
文摘A determination method for isotope ratios of iron in faeces samples is studied in this paper. The sample is decomposed in microwave oven by HNO3. A double focusing ICP-MS mass spectrometer (ELEMENT) working at resolution of 3000 allows the complete resolution of polyatomic ions overlapping. Instrumental parameters of the mass spectrometer are optimized for optimum precision. The RSD values obtained for the isotope ratios of 54Fe/56Fe, 57Fe/56Fe and 58Fe/56Fe are 0.23, 0.14, 0.22%, respectively, for a natural standard solution of 5ug/ml. The method has been used to iron nutrition studies.
