塔里木盆地西部含盐系地层成盐元素的地球化学初步研究   总被引：3，自引：1，他引：3       下载免费PDF全文

马万栋  马海州  谭红兵  张西营 《盐湖研究》2003,11(2):35-40

钾矿是我国目前紧缺的矿种之一 ,钾矿的寻找对我国有着十分重要的意义。塔里木盆地是我国第三系地层的广泛发育区域 ,有一定的找钾远景 ,尤其是库车、莎车等地区。通过对塔里木盆地 (坳陷 )西部的区域地质概况、成矿条件等的介绍 ,运用地球化学的分析测试手段 ,对塔里木盆地西部采集到的样品作了地球化学分析。论述了该区成盐沉积的地球化学特征 ,并讨论了该区形成钾矿的可能性。  相似文献   

The Global Distribution of Secondary Particulate Matter in a 3-D Lagrangian Chemistry Transport Model     

R. G. Derwent  W. J. Collins  M. E. Jenkin  C. E. Johnson  D. S. Stevenson 《Journal of Atmospheric Chemistry》2003,44(1):57-95

A global 3-D Lagrangian chemistry-transport model STOCHEM is used to describe the tropospheric distributions of four components of the secondary atmospheric aerosol: nitrate, sulphate, ammonium and organic compounds. The model describes the detailed chemistry of the formation of the acid precursors from the oxidation of SO₂, DMS, NO_x, NH₃ and terpenes and their uptake into the aerosol. Model results are compared in some detail with the available surface observations. Comparisons are made between the global budgets and burdens found in other modelling studies. The global distributions of the total mass of secondary aerosols have been estimated for the pre-industrial, present day and 2030 emissions and large changes have been estimated in the mass fractions of the different secondary aerosol components.  相似文献   

利用不纯净十水芒硝与纯净氯化钾制取硫酸钾的研究   总被引：1，自引：0，他引：1       下载免费PDF全文

张树群  牛自得 《盐湖研究》1997,5(2):30-35

本文通过相图分析，对利用不纯净十水芒硝与纯净氯化钾通过二步转化制取硫酸钾进行了物料配比计算．给出了最佳物料配比及十水芒硝中氯离子的最大含量，对实际生产有指导意义。  相似文献   

察尔汗盐湖钾盐矿床与晶间卤水分异的关系     

徐少康 《盐湖研究》1996,4(2):64-69

通过钾盐矿床与晶间卤水分异特征及成因的分析对比，认为晶间卤水分异的过程也就是钾盐矿床形成的过程。胶结浸染状固体矿形成于晶间卤水分异初期的浓缩阶段，改造于分异后期的淡化阶段；晶间卤水矿和层状固体矿形成于淡化阶段。  相似文献   

Effect of environmental factors on the flora of alluvial fans in southern Sinai     

Abd El-Raouf A. Moustafa  A. Zayed 《Journal of Arid Environments》1996,32(4):431-443

The purpose of this study was to elucidate the floristic and structural characteristics of simple alluvial fan vegetation of southern Sinai and to relate them to environmental variation. The main question addressed was: how does the floristic composition of fan habitats, species richness and life-form vary in relation to environmental change? Thirty-seven alluvial fans, randomly selected in two mainwadis(WadiFeiran andWadiDahab) were analysed quantitively. Two-way Indicator Species Analysis (TWINSPAN) classification and Canonical Correspondence Analysis (CCA) were applied in successive stages of the data analysis to describe vegetational variation in relation to physical gradients. Seven main clusters of fans were defined on the basis of environmental variation. These clusters are divided into three main groups of species richness. Species richness varied along a moisture gradient. The richest fans were the driest habitats, indicating that maximum species richness did not occur at high moisture availability. The moisture gradient is a complex gradient correlated with elevation, slope, climatic aridity, soil texture and the nature of the soil surface. Fine sand, silt plus clay and calcium carbonate showed significant differences between the internal groups and subgroups of the first and second level of the TWINSPAN classification.  相似文献   

A Reflection on Mg, Cd, Ca, Li and Si Isotopic Measurements and Related Reference Materials   总被引：6，自引：1，他引：6  

Jean Carignan  Damien Cardinal  Anton Eisenhauer  Albert Galy  Mark Rehkamper  Frank Wombacher  Nathalie Vigier 《Geostandards and Geoanalytical Research》2004,28(1):139-148

This contribution aims to report the reflections we had with the scientific community during two international workshops on reference materials for stable isotopes in Davos (2002) and Nice (2003). After evaluating the isotopic homogeneity of some existing reference materials, based on either certificates, literature data or specific inter-laboratory rounds, we confirm these as primary reference materials or propose new ones relative to which stable isotope compositions should be reported. We propose DSM-3 for Mg, NIST SRM 915a for Ca, L-SVEC for Li and NBS28 for Si. Cadmium does not yet have a well identified delta zero material, although three commercial mono-elemental Cd solutions have yielded the same isotopic composition relative to one another. In order to scale the linearity of any mass spectrometer, some secondary reference materials are also proposed: Cambridge-1 solution for Mg, the "Münster-Cd" and JEPPIM Cd solutions for Cd and the "Big Batch" silicate for Si. The team from Nancy propose to prepare a mixed spike solution for Li isotopes. Well-characterised natural samples such as ocean or continental waters, diatoms, sponges, rocks and minerals are needed to validate the entire analytical procedure, particularly to take into account the effect of sample mineralisation and of chemical manipulations for elemental separation prior to analysis.  相似文献   

新疆罗布泊超大型卤水钾矿发现20年     

宣之强 《化工矿产地质》2016,(1):60-64

"罗布泊超大型卤水鉀矿"的发现,是中国众多地学科学家40年探寻预测的。王弭力研究员及其团队,于1995年秋首次踏进罗布泊"罗北凹地",当年找到4356万t优质卤水鉀矿;经五年科研和勘探,查明儲量达2.5亿t、为超大型卤水鉀矿。理论创新,成为完成科硏和勘探的关键,加速了百万吨级"罗钾公司"硫酸钾肥生产成功投产。古丝绸之路上生命回归、一颗新星"罗布泊"镇诞生,"百年罗钾"资源保障科研探钾即将启动,中国几代"钾盐人"的梦想成真。  相似文献   

Effects of heavy metal (Pb) concentration on some growth parameters of plants grown in lead polluted soil under organic fertilizer amendment     

Ojo M. Oseni  Adekunle A. Adelusi  Esther O. Da  Abdulfatai B. Rufai 《寒旱区科学》2016,8(1):36-45

This study investigated morphological variation and biomass accumulation that occurred in Sida acuta and Chromolaena odorata plants grown in lead polluted soil under organic fertilizer amendment. The study was carried out in the screen house at the Biological Gardens of the Obafemi Awolowo University, Ile-Ife, Osun State. The experiment was a factorial combination of one heavy metal (Pb) at five levels of concentration (0, 200, 400, 800 and 1,000 mg/kg) in a completely randomized design, and were replicated three times for each of the two plants and two levels (0 g/kg and 9.4 g/kg) of organic fertilizer (OBD-Plus). Each pot was filled with 5 kg of air-dried and sieved soil and placed on a plastic tray for the collection of excess water. Two weeks after planting, seedlings of uniform height were transplanted from the nursery to experimental pots at the rate of one seedling per pot and grown for 10 weeks. The growth parameters of the plants were biomonitored for 7 weeks. After 10 weeks of treatment, the plants were harvested and dried to calculate the biomass accumulation. The two plant species performed better under fertilizer application than without it. For each of the plant species the growth parameters decreased as the levels of Pb concentration increased. Furthermore, the plants' biomass decreased significantly (p<0.05) as the levels of Pb concentration increased. The organic fertilizer helped to improve the plants' performance in lead-polluted soil.  相似文献   

Travel time controls the magnitude of nitrate discharge in groundwater bypassing the riparian zone to a stream on Virginia's coastal plain     

Samuel A. Flewelling  Janet S. Herman  George M. Hornberger  Aaron L. Mills 《水文研究》2012,26(8):1242-1253

Groundwater that bypasses the riparian zone by travelling along deep flow paths may deliver high concentrations of fertilizer‐derived NO₃^? to streams, or it may be impacted by the NO₃^? removal process of denitrification in streambed sediments. In a study of a small agricultural catchment on the Atlantic coastal plain of Virginia's eastern shore, we used seepage meters deployed in the streambed to measure specific discharge of groundwater and its solute concentrations for various locations and dates. We used values of Cl^? concentration to discriminate between bypass water recharged distal to the stream and that contained high NO₃^? but low Cl^? concentrations and riparian‐influenced water recharged proximal to the stream that contained low NO₃^? and high Cl^? concentrations. The travel time required for bypass water to transit the 30‐cm‐thick, microbially active denitrifying zone in the streambed determined the extent of NO₃^? removal, and hydraulic conductivity determined travel time through the streambed sediments. At all travel times greater than 2 days, NO₃^? removal was virtually complete. Comparison of the timescales for reaction and transport through the streambed sediments in this system confirmed that the predominant control on nitrate flux was travel time rather than denitrification rate coefficients. We conclude that extensive denitrification can occur in groundwater that bypasses the riparian zone, but a residence time in biologically active streambed sediments sufficient to remove a large fraction of the NO₃^? is only achieved in relatively low‐conductivity porous media. Instead of viewing them as separate, the streambed and riparian zone should be considered an integrated NO₃^? removal unit. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

气溶胶气候效应的一维模式分析   总被引：4，自引：1，他引：4  

赵凤生  石广玉 《大气科学》1994,18(Z1):902-909

本文首先采用一线辐射对流模式，分析了乡村型、城市型气溶胶和平流层气溶胶含量增加对全球地表气温的直接影响以及硫酸盐粒子含量增加对全球地表气温的间接影响。然后利用考虑了海洋热惯性作用的ＥＢＭ／ＢＤ模式，模拟了近百年来由于大气中硫酸盐粒子含量变化、火山爆发和大气温室气体浓度增加共同引起的全球地表平均气温变化。结果表明：气溶胶的气候效应在地气系统辐射收支和全球气温变化研究中起着非常重要的作用。  相似文献