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Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science china Earth sciences 2008年第12期51卷 1776-1785页

作者： xiao yingkai1,2, li hualing1,3, liu weiguo4, wang xiufang1 & jiang shaoyong5 1 qinghai institute of salt lakes, chinese academy of sciences, xining 810008, china 2 State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3 Nanjing institute of Geology and Mineral Resources, Nanjing 210016, china 4 State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 5 State Key Laboratory for Mineral Deposits Research, Department of Earth sciences, Nanjing University, Nanjing 210093, china qinghai institute of salt lakes Chinese Academy of Sciences Xining China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China Nanjing institute of Geology and Mineral Resources Nanjing China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34 was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4-pH curves and neither do they exactly parallel any theoretical δ 11B4-pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4- in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4-3) between B(OH)4- and B(OH)3 is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

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Boron Isotopic Fractionation and Trace Element Incorporation in Various Species of Modern Corals in Sanya Bay, South china Sea

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Journal of Earth Science 2014年第3期25卷 431-444页

作者： Haizhen Wei shaoyong jiang yingkai xiao N Gary Hemming State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth ResourcesChina University of Geosciences Wuhan qinghai institute of salt lakes Chinese Academy of Sciences Lamont-Doherty Earth Observatory of Columbia University Queens College School of Earth and Environmental sciences

The boron isotope paleo-pH proxy has been extensively studied due to its potential for understanding past climate change, and further calibrations were considered for accurate applications of the proxy because of significant variability related to biocarbonate microstructure. In this work, we studied the boron isotopic fractionation between modern marine corals and their coexisting seawater collected along shallow area in Sanya Bay, South china Sea. The apparent partition coefficient of boron（KD） ranged from 0.83×10-3 to 1.69×10-3, which are in good agreement with previous studies. As the analyzed coral skeleton（~5 g） spanned the growth time period of 1–2 years, we discussed the boron isotopic fractionation between pristine corals and modern seawater using the annual mean seawater pH of 8.12 in this sea area. Without taking the vital effect into account,（11B/10B）coral values of all living corals spread over the curves of（11B/10B）borate vs.（11B/10B）sw with the α4-3 values ranging from 0.974 to 0.982. After calibrating the biological effect on the calcifying fluid pH, the field-based calcification on calcifying fluid pH（i.e., Δ（pHbiol-pHsw）） for coral species of Acropora, Pavona, Pocillopora, Faviidae, and others including Proites are 0.42, 0.33, 0.36, 0.19, respectively, and it is necessary to be validated by coral culturing experiment in the future. Correlations in B/Ca vs. Sr/Ca and B/Ca vs. pHbiol approve temperature and calcifying fluid pH influence on skeletal B/Ca. Fundamental understanding of the thermodynamic basis of the boron isotopes in marine carbonates and seawater will strengthen the confidence in the use of paleo-pH proxy as a powerful tool to monitor atmospheric CO2 variations in the past.

关键词： boron isotope paleo-pH proxy boron isotopic fractionation trace element modern coral.

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Boron isotopic composition of Paleozoic brachiopod and coeval coral calcites in Yunnan-Guizhou Plateau, china

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Science china Earth sciences 2011年第12期54卷 1912-1925页

作者： MA YunQi xiao yingkai HE MaoYong xiao Jun SHEN Quan jiang ShengXiang Lanzhou institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Key Laboratory of salt Lake Resources and Chemistry Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi ＇an 710075 China Geological Team 1 Yunnan Geoexploration and Development Bureau of Mineral Resources Qujing 655000 China Graduate University of chinese academy of sciences. Beijing 100049. China

Boron isotope values in Paleozoic brachiopods and corals, collected from the Yunnan-Guizhou Plateau, china, can be used to constrain the boron isotope compositions of past oceans. All brachiopod shells and coral samples were screened for diagenetic recrystallization by cathodoluminescence microscopy, trace element geochemistry of B, Fe, Mn, Sr, and scanning electron microscopy. The boron isotope ratios for brachiopods in Silurian, Devonian, Carboniferous, and Triassic calcites are in the ranges 8.9‰-14.0‰, 8.8‰-13.8‰, 10.3‰-16.3‰, and 6.7‰-12.4‰, respectively. The boron isotope ratios of coral calcites in the Silurian, Devonian, and Permian are 9.1‰-12.2‰, 6.1‰-13.8‰, and 9.2‰-16.1‰, respectively. The δ11B values for both brachiopods and corals are significantly lower than those for modern biogenic carbonates, indicating that the Paleozoic oceans were depleted of δ11B by up to 10‰. Our results are consistent with previous published studies. The boron isotope compositions of corals and brachiopods show the consistent trends. The low δ11B values may be explained by an enhanced riverine flux of boron from the continents.

关键词： boron isotope coral brachiopod Paleozoic

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偕胺肟化FDU-12的制备及对U(Ⅵ)的高效富集研究

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环境科学学报 2024年第7期44卷 137-149页

作者：肖江赵博石成龙贾永忠中国林业科学研究院亚热带林业研究所杭州311400 中国科学院青海盐湖研究所西宁810008 青海民族大学化学化工学院西宁810007 华北水利水电大学环境与市政工程学院郑州450046

随着核工业的大力发展,铀资源的短缺以及产生的含铀废水严重制约着环境和人类可持续发展,高效铀吸附材料研发对保障能源和环境安全具有重要意义.本研究以Pluronic F127(EO106PO70EO106)为表面活性剂,1,3,5-三甲苯(TMB)为有机膨胀剂,通... 详细信息

随着核工业的大力发展,铀资源的短缺以及产生的含铀废水严重制约着环境和人类可持续发展,高效铀吸附材料研发对保障能源和环境安全具有重要意义.本研究以Pluronic F127(EO106PO70EO106)为表面活性剂,1,3,5-三甲苯(TMB)为有机膨胀剂,通过四乙氧基硅烷(TEOS)与2-氰乙基三乙氧基硅烷(CPTES)的共缩合及化学还原技术制备了三维笼状介孔分子筛FDU-12(FDU为复旦大学)和偕胺肟化FDU-12(AO@FDU-12)介孔材料.采用光谱分析表征FDU-12和AO@FDU-12的元素组成和微观结构,探究不同物质的量的比投加量对合成材料的物化性质的影响,并考察反应时间、温度、pH、离子强度和共存阴阳离子等环境因素对FDU-12和AO30@FDU-12吸附水溶液中U(Ⅵ)的影响.结果表明,制备过程中TEOS与CPTES的物质的量的比对材料的三维孔结构和铀吸附性能影响较大,随着CPTES物质的量的增加,材料的孔结构由规则变为无序,且以AO30@FDU-12对U(Ⅵ)的吸附效果最优;批量吸附实验研究表明,U(Ⅵ)在FDU-12和AO30@FDU-12吸附过程很快,达到吸附平衡时间分别为20 min和45 min;溶液pH对FDU-12和AO30@FDU-12吸附U(Ⅵ)有很显著影响,而离子强度对两种材料吸附U(Ⅵ)无明显变化;吸附动力学和热力学研究表明,U(Ⅵ)在AO30@FDU-12上的吸附行为是一个化学吸附、自发吸热过程,符合Langmuir单层吸附模型,最大饱和吸附容量可达300.95 mg·g^(-1)(T=298 K,pH=5.0).此外,AO30@FDU-12的还具有良好的放大和循环使用性能,再考虑到AO30@FDU-12对U(Ⅵ)的优异的吸附性能,在净化和富集水溶液中U(Ⅵ)具有巨大的应用潜力.

关键词：偕胺肟化 FUD-12 U(Ⅵ) 吸附共缩合

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4-硝基苯并-15-冠醚-5液液萃取分离锂同位素

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盐湖研究 2019年第3期27卷 62-67页

作者：王苏贾永忠王兴权肖江姚颖张全友景燕中国科学院青海盐湖研究所盐湖资源综合高效利用重点实验室青海西宁810008 中国科学院大学北京100049

以4-硝基苯并-15-冠醚-5(4-NO2-B15C5)做萃取剂,苯甲醚和1-丁基-3-甲基咪唑双(三氟甲烷磺酰)亚胺盐([C4mim][NTf2])作稀释剂和协萃剂,以1 mol/L liCl溶液作萃取溶剂,构建高效的冠醚—离子液体/锂盐溶液的溶剂萃取体系。重点考察了有机... 详细信息

以4-硝基苯并-15-冠醚-5(4-NO2-B15C5)做萃取剂,苯甲醚和1-丁基-3-甲基咪唑双(三氟甲烷磺酰)亚胺盐([C4mim][NTf2])作稀释剂和协萃剂,以1 mol/L liCl溶液作萃取溶剂,构建高效的冠醚—离子液体/锂盐溶液的溶剂萃取体系。重点考察了有机相组成、冠醚浓度和锂盐阴离子等对锂同位素分离的影响。结果表明,4-硝基苯并-15-冠醚-5具有良好的锂同位素分离效果,在萃取CF3COOli时最大单级分离系数(α)可达1.043±0.01。

关键词：锂同位素 4-硝基苯并-15-冠醚-5 溶剂萃取分离离子液体

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