碱熔沉淀-等离子体质谱法测定地质样品中的多元素   总被引：14，自引：17，他引：14       下载免费PDF全文

王蕾  何红蓼李冰 《岩矿测试》2003,22(2):86-92

采用过氧化钠焙融或偏硼酸锂熔融分解样品，将提取液碱性沉淀，通过过滤分离掉大量熔剂，再将沉淀用酸复溶后用等离子体质谱测定26个元素。通过对比，偏硼酸锂熔融—酸提取—碱性沉淀的方案，空白低，易操作，成本低，大多数元素测定结果的相对误差＜10％，相对标准偏差＜5％(n＝10)，与标准值相吻合。  相似文献   

钾-氩和氩-氩定年样品的送样要求及预处理   总被引：11，自引：1，他引：11  

刘玉琳苗国均  黄宝玲 《岩矿测试》2003,22(4):297-299

介绍了K-Ar和Ar-Ar法定年样品的送样要求及实验室预处理程序，样品粒度以250～180μm为宜；用量则视样品的K含量和年龄情况而定，K含量越高、年龄越老，所需样品量越少，多数样品的用量在几十至几百毫克；对于年龄情况不清楚的样品，10～20g手标本或者1～2g合适粒度的样品可以保证用量。全岩样品常受蚀变和捕虏晶的影响，有效的预处理可以在很大程度上消除这些干扰因素。文章还介绍了用稀HNO3消除碳酸盐、1．7mol／L HF消除轻微蚀变的影响以及电磁选剔除捕虏晶的实验过程。  相似文献   

成都市浮尘物理与化学特征的初步研究   总被引：4，自引：2，他引：4  

陈岳龙  杨忠芳  陈德友  唐金荣  郑妍  赵俊香 《物探与化探》2003,27(6):484-486,483

通过对成都市一环、二环路交叉处和纵贯市区人民路浮尘进行粒度、X射线衍射物相、元素组成等分析,研究了成都市浮尘的成分、元素含量、组合特征及其在空间的分布特征,对降低浮尘污染提出了初步建议.  相似文献   

水化学指标表示裘布依公式的应用   总被引：2，自引：0，他引：2  

侯玉新 《水文地质工程地质》2003,30(4):97-101

从多矿物溶解化学动力学方程出发,推演并建立了由水化学指标表示的承压二维井流裘布依公式。结合水文地质、水文地球化学特征,列举了水文地质单元内不同区带、各种代表性矿物及相应组分化学指标的基本表达式。以山西省太原西峪煤矿所需解决的水文地质问题为例进行了定量研究与评价,其结果与已有的抽水试验资料接近,为矿井涌水量的评价开辟了一条新的道路。从事实上进一步论证了水化学指标表示裘布依公式的理论概括是正确的。  相似文献   

电子探针化学测年方法   总被引：7，自引：0，他引：7  

李学军  郭涛  王庆飞 《地学前缘》2003,10(2):411-414

介绍含Th U Pb矿物电子探针化学测年方法的基本原理 ,并利用应用实例说明该方法在研究岩石形成年龄、构造热事件年代等方面的重要作用 ,最后简要评价该方法的优、缺点 ,并指出它的应用前景 ,认为电子探针化学测年方法将有可能在深源岩石包体年龄研究、含放射性元素矿床形成年代研究等方面大有作为 ,并使地质年代学研究更加精细化 ,有助于深入探讨复杂地质事件及其演化历程。  相似文献   

大兴安岭阿龙山地区流纹岩风化的地球化学特征   总被引：5，自引：1，他引：5  

马力  郝立波  潘军  刘洪涛  段国政 《吉林大学学报(地球科学版)》2003,33(3):296-299,314

通过大兴安岭地区两个流纹岩风化剖面的研究发现，大兴安岭地区的岩石风化过程具有特殊性。风化过程分为两个阶段，即以化学风化为主导的基质风化阶段和以机械风化为主导的斑晶风化阶段，第二阶段显示出与正常风化剖面相反的风化趋势。低温和长冬使第二风化阶段延长，并呈现逆风化趋势。风化过程中Fe和Al始终处于流失状态。上述特征的产生是由原岩的结构及成分、气候因素和生态系统等多种因素作用的结果。  相似文献   

煤岩显微组分热解气相色谱特征与化学结构剖析   总被引：3，自引：0，他引：3       下载免费PDF全文

孙旭光  陈建平等 《地质学报》2003,77(1):135-143

煤结构是目前地球化学研究领域中的一个难点，但却具有极其重要的理论及实际意义，本文采用分步热解气相色谱技术将树皮体，镜质体和丝质体分解为分子量较小的可测定的有机化合物，在此基础上，据不同温度下热解产物的组成特征来还原显微组分的化学结构，实验结果表明，煤显微组分主要由四大类官能团组成，一是热稳定性较低的NOS杂原子官能团；二是脂族（脂链、脂环）结构；三是苯、烷基苯（甲苯、二甲苯）、萘等芳香族化合物，四是热稳定性很高的难以分解的稠环芳烃。上述四类化合物集中于显微组分的不同结构简单中，树皮体和镜质体结构单元外侧主要由热稳定性较低的杂原子化合物以及分子量较小的苯和烷基苯组成，而丝质体结构单元外侧则主要以短链脂族结构为主，三组分结构核部由热稳定性很高的难以分解的稠环芳烃组成。连结核部稠环芳烃与结构单元外侧杂原子等官能团的主要是热稳定性较高的脂链结构，煤显微组分热成烃主要按结构中各官能团键的强弱随热演化程度的加深依次脱除，生成油气，基本上属平行独立依次反应机制，亦“官能团脱除型”，此外，还包括少量的长链脂族结构裂解为短链脂肪烃的“解聚”过程。  相似文献   

A Linear Programming Approach to Determine the Normative Composition of Sedimentary Rocks     

V. N. Podkovyrov  O. V. Graunov  R. L. Cullers 《Mathematical Geology》2003,35(4):459-476

The analysis of modal and normative composition of sedimentary rocks is widely used for studying their sources and tectonic settings. The normative calculation of the mineral composition of rocks in this study is formulated as a linear programming problem and is solved by means of the simplex method. This enables both simultaneous and successive subtraction of a set of basic minerals from a rock sample represented by its chemical composition {SiO₂...LOI}. Such an approach provides a more exact calculation of the contribution of basic minerals in the rock. This mathematical approach is used to study two representative sets of sandstones and fine-grained rocks from a Meso- to Neoproterozoic marginal basin of southeastern Siberia (Uchur–Maya region, Yakutia) and a Pennsylvanian-Lower Permian uplifted continental block in Colorado, USA. The calculated normative mineral compositions of the Siberian sandstones are consistent with the observed modal compositions. These sandstones vary from K- Feldspar rich arkoses at the base of the sequence (the Uchur Group, lower Riphean) to quartz arenites or lithic sandstones and wacke in transgressive successions of the middle-upper Riphean. Arkoses and quartz arenites are dominant in Meso- to Neoproterozoic Siberia. These samples represent craton interior uplifted basement and quartzose, recycled orogen provenance of a stable craton in Rodinia. There are higher but consistent discrepancies between the calculated and observed compositions for the Pennsylvanian to Lower-Permian arkoses and quartz arenites (Sangre de Cristo, Belden, and Maroon Formations). The differences between the predicted and observed mineralogy may be due to uncertainties in the modes in the matrix and cement of the sandstones. This normative program should supplement modal calculations and provide better genetic constructions, especially in case of matrix-rich sandstones.  相似文献   

A mathematical model of concentrate solids content for the wet drum magnetic separator     

John G. Rayner  T. J. Napier-Munn   《International Journal of Mineral Processing》2003,70(1-4):53-65

Low concentrate density from wet drum magnetic separators in dense medium circuits can cause operating difficulties due to inability to obtain the required circulating medium density and, indirectly, high medium solids losses. The literature is almost silent on the processes controlling concentrate density. However, the common name for the region through which concentrate is discharged—the squeeze pan gap—implies that some extrusion process is thought to be at work. There is no model of magnetics recovery in a wet drum magnetic separator, which includes as inputs all significant machine and operating variables.A series of trials, in both factorial experiments and in single variable experiments, was done using a purpose built rig which featured a small industrial scale (700 mm lip length, 900 mm diameter) wet drum magnetic separator. A substantial data set of 191 trials was generated in this work. The results of the factorial experiments were used to identify the variables having a significant effect on magnetics recovery.It is proposed, based both on the experimental observations of the present work and on observations reported in the literature, that the process controlling magnetic separator concentrate density is one of drainage. Such a process should be able to be defined by an initial moisture, a drainage rate and a drainage time, the latter being defined by the volumetric flowrate and the volume within the drainage zone. The magnetics can be characterised by an experimentally derived ultimate drainage moisture. A model based on these concepts and containing adjustable parameters was developed. This model was then fitted to a randomly chosen 80% of the data, and validated by application to the remaining 20%. The model is shown to be a good fit to data over concentrate solids content values from 40% solids to 80% solids and for both magnetite and ferrosilicon feeds.  相似文献   

止水帷幕在高层建筑深基坑中的应用   总被引：2，自引：0，他引：2  

周红丽 《岩土力学》2003,(Z1)

某高层建筑基坑西侧紧邻一道河沟,水量较大,采取三重管高压摆喷帷幕止水[1～4],施工完成后通过监测,未发现渗漏、地下水位明显下降和周围建筑物沉降现象。  相似文献