溶液结构研究发展策略浅议   总被引：1，自引：1，他引：1       下载免费PDF全文

房春晖  房艳 《盐湖研究》2006,14(3):52-57

溶液结构被定义为研究溶液中溶剂化物种的微观结构及其与宏观性质之间关系的科学。简单叙述了其研究对象和研究方法,详尽阐述了其科学意义,介绍了其研究现状以及主要进展,并讨论了其研究策略。  相似文献   

Calibrations for benthic foraminiferal Mg/Ca paleothermometry and the carbonate ion hypothesis     

H. Elderfield  J. Yu  P. Anand  T. Kiefer  B. Nyland   《Earth and Planetary Science Letters》2006,250(3-4):633-649

Benthic foraminiferal magnesium/calcium ratios were determined on one hundred and forty core-top samples from the Atlantic Ocean, the Norwegian Sea, the Indian Ocean, the Arabian Sea and the Pacific Ocean, mostly at sites with bottom water temperatures below 5 °C. Mg/Ca ratios are consistently lower, by  0.2 mmol/mol, in samples cleaned using oxidative and reductive steps than using oxidative cleaning. Differences between Cibicidoides species have been identified: Mg/Ca of Cibicidoides robertsonianus > Cibicidoides kullenbergi > Cibicidoides wuellerstorfi. Comparison with bottom water temperatures support observations of lowered Mg/Ca of C. wuellerstorfi at temperature below  3 °C compared with values predicted by published calibrations and from other Cibicidoides species. Hydrographic data shows that carbonate ion saturation (Δ[CO₃²⁻]) decreases rapidly below this temperature. An empirical sensitivity of Δ[CO₃²⁻] on Mg/Ca has been established for C. wuellerstorfi of 0.0086 ± 0.0006 mmol/mol/μmol/kg. A novel application using modern temperatures and Last Glacial Maximum temperatures derived via pore fluid modelling supports a carbonate ion saturation state effect on Mg incorporation. This may significantly affect calculated δ¹⁸O_seawater obtained from foraminiferal δ¹⁸O and Mg/Ca temperature.  相似文献   

Distribution of ionospheric O~ ion in synchronous altitude region     

史建魁  刘振兴  ZHANG T.L  郭兼善  张满莲  尚社平  罗熙贵 《中国科学D辑(英文版)》2003,46(10)

Since ions originating from the ionosphere were discovered in the magnetosphere in the be-ginning of 1970s[1], it is gradually confirmed that the ionosphere is a source of magnetospheric ion (the other source is solar wind). Research result on ionospheric…  相似文献   

Deep melting and sodic metasomatism underneath the highly oblique-spreading Lena Trough (Arctic Ocean)     

Eric Hellebrand  Jonathan E Snow 《Earth and Planetary Science Letters》2003,216(3):283-299

Abyssal peridotites collected along the highly oblique-spreading Lena Trough north of Greenland and Spitsbergen have mineral compositions that are similar to residual abyssal peridotites, except for high sodium concentrations in clinopyroxene (cpx). Most samples are lherzolites with light rare earth element (REE)-depleted cpx trace element patterns, but significantly fractionated middle to heavy REE ratios at relatively high heavy REE concentrations. Such characteristics can only be explained by initial melting of a garnet peridotite followed by low degrees of melting in the stability field of spinel peridotite. The residual garnet signature requires either a high potential temperature of the upwelling mantle, or elevated solidus-lowering water contents. The limited spinel field melting suggests a deep cessation of melt extraction, possibly because of the presence of a thick lithospheric cap. This is consistent with the extremely low effective spreading rate and the vicinity to a passive continental margin, which allow conductive cooling to reach deeper levels than commonly estimated for faster mid-ocean ridges. High sodium concentrations in cpx are neither explainable by melt refertilization, nor by a simple diffusion mechanism. The efficient fractionation of sodium from the light REE requires post-melting metasomatism, which is typically restricted to the subcontinental lithosphere. This might imply that the Lena Trough peridotites represent unroofed subcontinental mantle, from which no melt was extracted during the opening of the Lena Trough. It is more likely that sodic metasomatism occurred after partial melting underneath the Lena Trough, and that such an enrichment process is responsible for elevated sodium concentrations in abyssal peridotites elsewhere. Sodium in cpx of residual peridotites can therefore not serve as an indicator of partial melting or melt refertilization.  相似文献   

热液中银、铅、锌共生分异的实验研究   总被引：4，自引：1，他引：4  

尚林波  樊文苓  邓海琳 《矿物学报》2003,23(1):31-36

对NaCl—HCl—H2O体系中银、铅、锌氯络合物稳定性进行实验研究，结果表明：热液中银、铅、锌氯络合物的稳定性受体系温度、pH、Eh以及组分浓度的控制。相同温度下，H^ 、Cl^-浓度降低，还原硫增加，均使络合物趋于不稳定，发生不同程度的沉淀分异。当t=300℃,[Cl^-]=0.24mol/L,pH＝6．86时，铅氯络合物的沉淀量达55％，锌氯络合物的沉淀量超过92％。热液体系中硫化物的存在，对银的影响最大，溶液中的银氯络合物几乎沉淀完全，浓度可降至检测限以下。而铅和锌的氯络合物相对稳定。热力学计算表明：溶液中的银是以硫化银或自然银的形式沉淀析出。因此，还原硫的存在是导致热液体系中银与铅锌发生分异的重要因素。  相似文献   

两种质谱仪在辉钼矿铼-锇年龄测定中的应用比较     

梁树平  屈文俊  杜安道  杨刚  陈江峰 《岩矿测试》2004,23(4):268-272

对同一地区但Re、Os含量不同的一组辉钼矿样品,分别采用电感耦合等离子体质谱(ICP-MS)和负离子热表面电离质谱(NTIMS)对其Re-Os年龄进行了测定比较。结果表明,该组样品的平均Re-Os模式年龄分别为(138.3±4.0)Ma和(141.0±3.6)Ma(2σ,n=9),采用ISOPLOT软件的模式1进行等时线计算,得到等时线年龄分别为(138.6±2.9)Ma(2σ,n=9)和(141.6±1.9)Ma(2σ,n=9),两者在目前水平下的误差范围内基本一致。另外,分别采用ICP-MS和NTIMS对辉钼矿Re-Os年龄国家一级标准物质GBW04435和GBW04436进行了测定,所得的结果吻合也较好。  相似文献   

宝石中常见过渡金属离子致色的理论解释   总被引：5，自引：0，他引：5  

罗红宇王春生  廖尚宜 《岩石矿物学杂志》2004,23(2):177-180

从晶体场理论或配位场理论出发，应用群论的方法，从理论上系统地解释了宝石中常见的因过渡金属离子在不同的配位场环境下而引起的能级分裂，并详细地阐述了这一理论分析的程序，最后列举实例并给予了理论解释。  相似文献   

Hydrogen Isotopes of Glassy and Phyllosilicate Spherules in Al Rais (CR) and Orgueil (CI) Chondrites     

Michael E.ZOLENSKY 《《地质学报》英文版》2004,78(5)

The hydroxyl in phyllosilicate minerals is the most common occurrence of water in primitive meteorites. Direct hydrogen isotopic analysis of this water component using an ion microprobe has been made in some glassy or phyllosilicate spherules from the Al Rais (CR) and Orgueil (CI) chondrites. The spherules from Al Rais show large deuterium excesses (δD = +200 -+800‰) relative to terrestrial standards, whereas deuterium-enrichments in the spherules from Orgueil are much smaller (δD = +40 - +130‰). The phyllosilicate spherules are products of  相似文献   

海底沉积物中碳酸钙分析方法的研究   总被引：4，自引：0，他引：4  

宋苏顷  夏宁 《岩矿测试》1998,17(2):127-130

探讨了海底沉积物中ＣａＣＯ３的测定方法。用１ｍｏｌ／ＬＮａＡｃ＋ＨＡｃ做碳酸盐相＋离子交换相的浸取剂,１ｍｏｌ／ＬＮａＡｃ做离子交换相的浸取液,在沸水浴中３０ｍｉｎ分解样品,然后用ＡＡＳ或ＩＣＰＡＥＳ分别测定离子交换相＋碳酸盐相及离子交换相中的Ｃａ,差减法计算样品中ＣａＣＯ３含量。方法经深海沉积物、水系沉积物等国家标准物质验证,结果与标准值相符。对同一样品进行１２次测定,相对标准偏差小于５％。  相似文献   

HYDROGEN ION CONCENTRATION IN RAIN WATER     

J. Rosinski  G. Mancini  C. T. Nagamoto  F. Prodi 《Acta Meteorologica Sinica》1998,12(3):382-384

Continuous measurements of pH precipitation falling from cumulus clouds in semi-arid region(Colorado,USA),and in wet temperate zone(Bologna,Italy)were made.In Colorado the pHwas constant at 7.3 for a period of time,and later changed to 7.0 and remained constant at thisvalue during the remainder of the storm.In Italy the pH fluctuated continuously between theapproximate values of 5.7 and 6.4 during the storm.The changes in hydrogen ion concentrationreflect the chemical composition of cloud condensation nuclei and of scavenged aerosol particles andgases presented in the region.  相似文献