铅在高岭石表面的解吸动力学   总被引：3，自引：0，他引：3  

魏俊峰  吴大清  彭金莲  刁桂仪 《矿物岩石》2002,22(2):5-8

经过酸性条件下（pH=3.1)Pb(Ⅱ）高岭石表面解吸动力学的研究，发现解吸反应与吸附反应动力学相似，也是一个二阶段的过程，即初始的快速解吸之后伴随着一个缓慢的释放过程。在快速解吸阶段，7min内解吸量即已达到41％。吸附铅没有完全解吸，有近38％残留在高岭石表面，即解吸和吸附过程不是完全可逆的。解吸过程可以用扩展Elovich方程、Elovich方程、双常数方程和一级扩散方程较好地似合。  相似文献   

Al hematites prepared by homogeneous precipitation of oxinates: material characterization and determination of the Morin transition     

G. M. da Costa  E. Van San  E. De Grave  R. E. Vandenberghe  V. Barrón  L. Datas 《Physics and Chemistry of Minerals》2002,29(2):122-131

A novel method for synthesis of aluminium hematites, based upon the homogeneous precipitation of Fe and Al oxinates in various proportions, is presented. The precursor precipitates are heated in air at 700?°C. X-ray diffraction, thermal analyses, BET, FTIR, optical reflection analysis, TEM and Mössbauer spectroscopy at room temperature and 80?K of the resulting products indicate that single-phase hematites are formed with structural Al substitution of up to 10 at%. Interestingly, the particle size (>100?nm) is not substantially reduced by the Al content. Although it remains difficult to obtain a homogeneously distributed Al substitution in the final hematite, this processing line offers a unique opportunity to separate the effects of grain size and Al substitution on the Morin transition temperature (T _M) of Al hematite. From the comparison between the present hematites and a series of Al-substituted hematites with lepidocrocite as precursor, it could be shown that the effect on T _M, associated with a change of a factor 10 in grain size, is about 1/3 of the effect caused by a change of 10 in the degree of substitution. Finally, it is suggested that proper thermal treatments under different conditions of the same precursors are likely to produce spinel phases.  相似文献   

山地丘陵地区物探爆破孔钻机及配套机具的研究与开发          下载免费PDF全文

赵大军  孙友宏  侯传彬  薛军 《探矿工程》2002,(4):22-24

为满足我国山地丘陵地区物探爆破孔施工技术的要求，研究适合土层、岩层钻进用的钻机及工具，对钻机的配套设备进行了开发研究。分析了国内山地丘陵地区物探爆破孔施工技术现状，并着重介绍了研制设计内容及生产试验情况。  相似文献   

Wind velocity and sand transport on a barchan dune   总被引：2，自引：0，他引：2  

G. Sauermann  J. S. Andrade  Jr.  L. P. Maia  U. M. S. Costa  A. D. Araújo  H. J. Herrmann 《Geomorphology》2003,54(3-4):245-255

We present measurements of wind velocity and sand flux performed on the windward side of a large barchan dune in Jericoacoara, northeastern Brazil. From the measured profile, we calculate the air shear stress using an analytical approximation and treat the problem of flow separation by an heuristic model. We find that the results from this approach agree well with our field data. Moreover, using the calculated shear velocity, we predict the sand flux according to well-known equilibrium relations and with a phenomenological continuum saltation model that includes saturation transients and thus allows for nonequilibrium conditions. Based on the field data and theoretical predicted results, we indicate the principal differences between saturated and nonsaturated sand flux models. Finally, we show that the measured dune moves with invariant shape and predict its velocity from our data and calculations.  相似文献   

巴音宝力格隆起带中新生代盆地砂岩型铀矿成矿地质条件及远景分析   总被引：2，自引：2，他引：2  

李国新  孙泽轩  姚毅锋  黄大友 《铀矿地质》2003,19(3):148-153

本根据野外调查及室内系列编图成果，分析了巴音宝力格隆起带中新生代盆地砂岩型铀矿成矿地质条件，认为下白里统巴彦花组是中新生代盆地的找矿目的层位，并存在古河道与潜水层间氧化带两种砂岩型铀矿类型。巴彦毛都、准巴彦塔拉、乌里雅斯太和伊勒门盆地是形成砂岩型铀矿的远景盆地。  相似文献   

关于新疆煤炭工业可持续发展的思考     

黄道成  敬益武 《中国煤田地质》2003,15(6):101-103

阐述了新疆煤炭工业发展中存在的主要问题,分析了新疆煤田地质工作的发展方向及当前工作重点,并对新疆煤炭工业的可持续发展战略提出了政策性建议。  相似文献   

基于GIS技术的矿产资源信息系统   总被引：8，自引：3，他引：8  

蔡洪春  张春明  姜绍飞  陈为公  寇大明 《地质与资源》2003,12(2):111-114

地质资料基本上可以分为空间数据和属性数据两大类.它们是地学数据不可分割的两方面,客观上要求统一进行管理.采用地理信息系统技术,可以彻底解决两种类型数据统一管理问题.结合正在开展的辽宁省矿产资源勘查、开发与利用规划工作,论述了建立基于GIS技术的辽宁矿产资源信息系统实现数据可视化和空间模型分析的思路和实现方法.它为今后矿产资源管理工作实现全面科学化管理提供了现代化手段,也为制定行业发展规划以及进行生产决策提供了支持,进而促进地质找矿和矿产开发的工作部署朝思维可视化及思路多样化的方向发展.  相似文献   

地表剥蚀作用对地应力场反演的影响   总被引：2，自引：4，他引：2  

易达  陈胜宏 《岩土力学》2003,24(2):254-256

岩体自重和剥蚀作用都是形成岩体初始应力场的重要因素。在地应力回归分析中，反演所得岩体重度往往大于实测重度。通过算例说明，地表剥蚀作用因素是导致该结果的主要原因，并分析了由此产生的一些工程应用问题。  相似文献   

潮滩沉积环境与岩相对比研究   总被引：12，自引：1，他引：12  

王颖  朱大奎  曹桂云 《沉积学报》2003,21(4):539-546

潮滩沉积是海陆交互作用的产物,形成于海岸坡度平缓、有丰富的细粒泥沙供应,以潮流动力为主的低能海岸环境,尤以河-海作用活跃的边缘海环境最为发育。潮滩沉积以粉砂为主,由于涨落潮流往复循环,潮滩具有动力、沉积、地貌与生物群体的分带现象。因海平面涨落与波浪参与的扰动筛选,导致潮滩沉积中的粗粒沉积物含量及微地貌形态的变化。这些因素反映于潮滩沉积相中具有下列特点:粉砂与粘土质交互叠置的页状层理;原始沉积层自下向上,粒径组成逐渐变细;下部的粉砂质层具有波痕、鱼刺状或丘状的交错层理、透镜体与扰动结构,或潮水沟堆积的镶嵌沙体;上部淤泥质层中具有草根、龟裂、虫管与钙质填充物、泥砾、泥块等。将现代潮滩沉积与南京钟山北麓下三叠统的黄马青组砂页岩,以及海口马村的下更新统湛江组粘土、粉砂岩进行对比,据泥沙粒径、矿物组合与含量,盐度,特别是薄互层理,虫管与钙质填充,泥裂块,波痕与交错层理等多项对比,均具有极好的相似性,表明该两组岩层为古潮滩沉积。  相似文献   

Evolution and inheritance of a rock coast: western Galicia,northwestern Spain     

R. Blanco Chao  M. Costa Casais  A. Martínez Cortizas  A. Prez Alberti  A. S. Trenhaile 《地球表面变化过程与地形》2003,28(7):757-775

There is increasing evidence that shore platforms and other elements of rock coasts may be inherited, at least in part, from interglacial stages when sea level was similar to today's. Most of this evidence, which includes ancient beaches and datable terrestrial deposits, has been obtained from areas of resistant, slowly eroding rock, where the platforms often appear to be much too wide to have developed since the sea reached its present level. It is much more dif?cult to demonstrate that inheritance has occurred in areas of weaker rock, which generally lack any datable material. The coast of western Galicia in northwestern Spain has shore platforms in igneous and metamorphic rocks that were deeply weathered during the Tertiary. These platforms are closely associated with ancient beaches from the last interglacial stage, and associated periglacial and ?uvio‐nival deposits that covered and fossilized most of the Eemian platforms and cliffs during the late middle and late Weichselian glacial stage. The sedimentary processes and the thickness and facies of the sediments were determined by the height, aspect and gradient of the coastal mountains, and their distance from the coast. Radiocarbon dating, sedimentary analysis and platform morphology indicate that the shore platforms of Galicia have been inherited from at least the last interglacial stage. They were fossilized in places beneath thick Weichselian deposits and then exhumed during the Holocene transgression. The abundant evidence for inheritance in Galicia has important implications for other coasts in fairly weak rocks where such evidence is generally lacking. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献