微量地质样品铼锇含量及其同位素组成的高精度测定方法   总被引：4，自引：2，他引：4  

储著银  陈福坤王伟谢烈文  杨岳衡 《岩矿测试》2007,26(6):431-435

报道了采用新型IsoProbe—T热电离质谱计测定Os含量及其同位素组成和Neptune多接收器等离子体质谱仪（MC—ICPMS）测定Re含量的分析方法。样品化学处理采用Carius管溶样、小型蒸馏法分离和微蒸馏法纯化提取Os以及阴离子树脂交换分离Re的方法。采用IsoProbe—T质谱计测定Os同位素组成具有灵敏度高和精度高的特点。对溶液标样，采用多法拉第接收器系统测定Os总量低至0．2ng的样品时，平均^192Os^16O3-离子流强度可达100mV以上并可维持约20min，其^187Os／^188Os同位素比值的测定精度可优于0．1％（1RSD）。采用所建立的化学分离流程和高精度质谱测量方法，测定了铂族元素橄榄岩标样WPR-1中Re、Os含量和Os同位素组成，测定结果与文献报道值在误差范围内吻合。  相似文献   

X射线荧光光谱法测定土壤样品中碳氮硫氯等31种组分   总被引：3，自引：3，他引：3  

徐海刘琦  王龙山 《岩矿测试》2007,26(6):490-492

利用新型的ZSX Primus Ⅱ型X射线荧光光谱仪采用粉末压片法直接测定土壤样品中的C、N、S、Cl等31种元素。各元素分析晶体为N采用RX45，C采用RX61，Na、Mg采用RX25，C1、S、P采用Ge，Si、Al采用PET，其余元素均采用LiF200。结果表明，方法的检出限、精密度和准确度对绝大多数元素而言，均可满足多目标地球化学调查样品分析的质量要求：  相似文献   

X射线粉晶衍射法在萤石矿药鉴定与质量评价中的应用   总被引：1，自引：0，他引：1  

温海成迟广成  康延国于艳 《岩矿测试》2007,26(6):495-496499

利用X射线粉晶衍射仪对不同产地的萤石矿物药进行全谱扫描。根据X射线粉晶衍射5强峰确定萤石矿物药的主成分，并检测出萤石矿物药中的其他矿物成分。在矿物药所有组分半定量分析的基础上，对萤石矿物药质量进行评价。  相似文献   

氢化物发生-原子荧光光谱法测定面粉中微量砷     

王洪彬 《岩矿测试》2007,26(6):503-504

样品用硝酸-高氯酸混合酸消解，考察了氢化物发生-原子荧光光谱法测定面粉中微量砷的实验条件，包括混合酸和还原剂硼氢化钾的用量。方法测定砷的线性范围为0．0—30．0μg／L，仪器的检出限为0．26μg／L，加标回收率为94．0％-104．0％，方法的精密度（RSD，n=11）为1．16％。方法操作简便、快速、灵敏度高。  相似文献   

火焰原子发射光谱法测定碳化钛中微量钠     

黄俭惠邱丽  施意华 《岩矿测试》2007,26(6):507-508510

对火焰原子发射光谱法测定碳化钛中微量钠的条件进行了试验。样品用硝酸-氢氟酸溶解，在0．30mol／L硝酸介质中，以硝酸钾作消电离剂消除钠的电离干扰，饱和硼酸溶液络合试液中过量的氟离子。方法检出限为0．015μg／mL，样品加标回收率为97．6％-105．6％，方法的精密度（RSD，n=6）小于2．5％。  相似文献   

Identification of Microfabric of Kaolinite Clay Mineral Using X-ray Diffraction Technique     

Ajanta Sachan  Dayakar Penumadu 《Geotechnical and Geological Engineering》2007,25(6):603-616

A new method is introduced in this study to identify the microfabric (geometric arrangement of platelets) of cohesive soil using standard X-ray diffractometer. Various sampling techniques are used to prepare the Kaolinite clay samples with different microfabrics to assess the consistency and versatility of the proposed method. This method is based on identifying the presence of basal and prism peaks from the X-ray diffraction pattern and corresponding relative intensity values. The present study also demonstrates the conditions for which Scanning Electron Micrographs (SEM) are not capable of accurately identifying the microfabric of cohesive soils. The method proposed in this study uses relative amplitudes of basal and prism peaks avoiding difficult sample and surface preparation procedures, as used by previous researchers in their microfabric identification methods. The proposed method is found to be a rapid and accurate method for identifying the microfabric of Kaolinite clay and should prove to be valuable for routine implementation for studying structured natural clays.  相似文献   

氢化物-原子荧光法快速测定化探样品中微量硒和碲   总被引：2，自引：0，他引：2  

韦山桃  唐沈 《矿产与地质》2007,21(5):601-605

在沸水浴中用王水分解样品，以盐酸为还原剂，三价铁盐为干扰元素抑制剂（一般化探样品均含有铁，故无须另外加入），直接用氢化物一原子荧光光谱法测定化探样品中微量硒和碲。方法检出下限分别为：LD（Se）=0．1ng／L；LD（Te）=0．01ng／L。方法准确、简便、快速，可满足大批量化探样品中微量硒和碲的测定要求。用本分析方法测定不同基体成分的六个国家级化探标样中的硒、碲，测定结果与标准值基本一致，8次测定的标准偏差（RSD）分别为RSD（Se）=6．6％～9．5％，RSD（Te）=3．6％～8．4％。  相似文献   

Determination of Trace Elements (Ag, B, Ge, Mo, Sn, W, Tl) in Reference Samples of Soils and Bottom Sediments by Atomic Emission Spectrometry: A Traceability and Fitness-for-Purpose Study     

Albina I. Kuznetsova  Olga V. Zarubina  Olga A. Sklyarova 《Geostandards and Geoanalytical Research》2007,31(3):251-259

Reference samples of soils from the Institute of Applied Physics, Irkutsk (RIAP), the Institute of Geochemistry, Irkutsk (IGI) and the United States Geological Survey, Reston (USGS) were analysed with the aim of determining Ag, B, Ge, Mo, Sn, Tl and W abundances by an atomic emission method with air-stabilised D.C. arc excitation. Two series of reference samples of soils and bottom sediments, GSS-1-8 and GSD-1-12 (IGGE), were used to ensure the traceability link for the analytical results. Traceability was also demonstrated through the comparison of measured results by AES and ICP-MS methods. It is shown that the reference samples GSS-1-8 and GSD-1-12 satisfied the "fitness-for-purpose" criterion (uncertainty U of the certified value should be one-third to one-tenth the magnitude of routine laboratory data uncertainty S (S/U > 3-10)) and can be applied for calibrating AES techniques.  相似文献   

Swelling-induced volumetric strains internal to a stressed coal associated with CO₂ sorption     

C. zgen Karacan 《International Journal of Coal Geology》2007,72(3-4):209-220

It is generally accepted that typical coalbed gases (methane and carbon dioxide) are sorbed (both adsorbed and absorbed) in the coal matrix causing it to swell and resulting in local stress and strain variations in a coalbed confined under overburden pressure. The swelling, interactions of gases within the coal matrix and the resultant changes in the permeability, sorption, gas flow mechanics in the reservoir, and stress state of the coal can impact a number of reservoir-related factors. These include effective production of coalbed methane, degasification of future mining areas by drilling horizontal and vertical degasification wells, injection of CO₂ as an enhanced coalbed methane recovery technique, and concurrent CO₂ sequestration. Such information can also provide an understanding of the mechanisms behind gas outbursts in underground coal mines.The spatio-temporal volumetric strains in a consolidated Pittsburgh seam coal sample were evaluated while both confining pressure and carbon dioxide (CO₂) pore pressure were increased to keep a constant positive effective stress on the sample. The changes internal to the sample were evaluated by maps of density and atomic number determined by dual-energy X-ray computed tomography (X-ray CT). Early-time images, as soon as CO₂ was introduced, were also used to calculate the macroporosity in the coal sample. Scanning electron microscopy (SEM) and photographic images of the polished section of the coal sample at X-ray CT image location were used to identify the microlithotypes and microstructures.The CO₂ sorption-associated swelling and volumetric strains in consolidated coal under constant effective stress are heterogeneous processes depending on the lithotypes present. In the time scale of the experiment, vitrite showed the highest degree of swelling due to dissolution of CO₂, while the clay (kaolinite) and inertite region was compressed in response. The volumetric strains associated with swelling and compression were between ± 15% depending on the location. Although the effective stress on the sample was constant, it varied within the sample as a result of the internal stresses created by gas sorption-related structural changes. SEM images and porosity calculations revealed that the kaolinite and inertite bearing layer was highly porous, which enabled the fastest CO₂ uptake and the highest degree of compression.  相似文献   

Phase transition in CaSiO₃ perovskite     

Tetsuya Komabayashi  Kei Hirose  Nagayoshi Sata  Yasuo Ohishi  Leonid S. Dubrovinsky 《Earth and Planetary Science Letters》2007,260(3-4):564-569

A phase transition in pure CaSiO₃ perovskite was investigated at 27 to 72 GPa and 300 to 819 K by in-situ X-ray diffraction experiments in an externally-heated diamond-anvil cell. The results show that CaSiO₃ perovskite takes a tetragonal form at 300 K and undergoes phase transition to a cubic structure above 490–580 K in a pressure range studied here. The transition boundary is strongly temperature-dependent with a slightly positive dT / dP slope of 1.1 (± 1.3) K/GPa. It is known that the transition temperature depends on Al₂O₃ content dissolved in CaSiO₃ perovskite [Kurashina et al., Phys. Earth Planet. Inter. 145 (2004) 67–74]. The phase transition in CaSiO₃(+ 3 wt.% Al₂O₃) perovskite therefore could occur in a cold subducted mid-oceanic ridge basalt (MORB) crust at about 1200 K in the upper- to mid-lower mantle. This phase transition is possibly ferroelastic-type and may cause large seismic anomalies in a wide depth range.  相似文献