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1.
Analysis of the grade of mineral resources of Russia and other countries shows that end products that are competitive in terms of both technological and environmental criteria in the world market can only be obtained by the development and implementation of progressive technologies based on the up-to-date achievements of fundamental sciences. The essence of modern innovation processes in technologies developed in Russia for the complex and comprehensive processing of refractory raw materials with a complex composition is ascertained. These processes include (i) radiometric methods of concentration of valuable components, (ii) high-energy methods of disintegration of highly dispersed mineral components, and (iii) electrochemical methods of water conditioning to obtain target products for solving specific technological problems.  相似文献   

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This paper addresses the main mechanisms controlling the continuous and geologically long evolution of the water-rock system, which produced diverse hydrogenous mineral complexes. The concept of such complexes was introduced by the author. It was shown that the water-rock system is a steady-state and equilibrium-disequilibrium one. Its development occurs in a far from equilibrium region and results in the formation of fundamentally new mineral associations and geochemical types of water. Taking into account that water is the main factor controlling the evolutionary trend of this system, it is argued that this system must be among the most important targets of hydrogeology.  相似文献   

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罗布泊罗北凹地承压卤水主要储集于钙芒硝层,钾含量高(>0.5%),是该区重要的后备钾盐资源之一.本文利用大气联通法及辅助孔注入卤水法,对罗布泊罗北凹地钾矿区富水性较差的3~11采卤井进行了改造.五次大规模、长时间段的抽水试验结果表明,上述技术手段改善了深部承压卤层的储集结构,有效增强了含水层水力联系,提高了含水层单位涌...  相似文献   

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A rapid and reliable method for analyzing Fe and Ca in low-rank Greek coals was developed. The presence of Fe and Ca is of importance regarding the potential use of these coals as raw material for organomineral fertilizers. Samples were collected from the main Greek lignite deposits and standards were prepared using Atomic Absorption Spectroscopy (AAS), which were also employed in the Energy Dispersive X-ray Fluorescence (EDXRF) method. The new method offers the advantages of being timesaving, non-destructive and can be easily incorporated in a fertilizer production line. Analysis of low-rank Greek coals demonstrated a significant Fe and Ca content ranging from 0.15 to 1.97 wt.% for Fe and from 0.04 to 2.51 wt.% for Ca. When both EDXRF and AAS techniques were applied, the Fe and Ca concentration values differed less than 5%, demonstrating that both techniques are reliable for low-rank coals in the above concentration range. These EDXRF results may be used as a preliminary test regarding the application of Greek coals in organomineral fertilizer production, given that in these coals iron and calcium are the most abundant metals.  相似文献   

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管内投砾新工艺在水文水井围填滤料中的应用   总被引:1,自引:0,他引:1       下载免费PDF全文
水文水井滤料围填的质量对供水水质及使用寿命具有重要影响,常规填料工艺经常出现"架桥"现象和投砾不到位的问题。为此,提出了一种管内投砾新工艺,可以克服上述缺陷。首先阐述了其核心设备—专用转换接头的基本原理,介绍了其施工工艺流程;最后基于两个工程实例,分析了设计与施工方面的难点并给出了相应的解决方案。结果表明:(1)与常规工艺相比较,管内投砾法既能够实现止水、注浆和固井的一体化操作,又能够减少成井环节,缩短成井周期,经济效益显著,可靠度100%;(2)采用专用转换接头围填滤料,能够保证水文水井滤料的充填质量,工艺简单易行、安全高效;(3)在深井投砾时,应安装井口自动投砾器;在井管内宜设置投砾导向管,并采用动水投砾。  相似文献   

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Potentiometric measurements of the stoichiometric constants for the dissociation of carbonic acid in NaCl solutions ( and ) have been made as a function of molality (0-6 m) and temperature (0-50 °C). The results have been fitted to the equations
  相似文献   

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范留明 《岩土力学》2013,34(9):2715-2720
平面波的传播问题通常可以归结为一维波动方程的定解问题。在非均匀介质中,即使简单的一维波动方程也需要借助于数值方法获得近似解。3层5点古典差分格式是计算偏微分方程一种常用算法,作为一种显式迭代格式,需要满足稳定性条件 ,其中 为波速, 为空间采样间隔, 为时间采样间隔。当 时, ,古典差分格式达到临界稳定状态。在这种情况下,平面波在 时间内的传播距离恰好等于空间采样间隔,差分格式真实地反映了平面波的传播原理,因而可以得到一维波动方程的精确解。但是,由于在非均匀介质中存在不连续的波阻抗界面,此方法不适于计算非均匀介质的波场。为了将临界稳定情况下的古典差分格式推广应用至非均匀层状介质,提出了一种能够处理波阻抗界面的有限差分格式,并应用傅里叶分析法得到其稳定性条件。模型算例验证了此算法的正确性。  相似文献   

9.
De-icing salt (NaCl) application is a common practice during winter road maintenance in northern countries, compromising ecosystem services. Ecoengineering facilities, including reactive filter beds, are becoming an effective strategy for road runoff management. Different materials (anthracite coal, dolomite, limestone, and pozzolan) were tested as reactive media of filter beds. Characterization showed that dolomite has the best physical properties (resistance to fragmentation, porosity) for filter bed construction and maintenance, followed by limestone. NaCl removal efficiency was investigated in batch at different concentrations (150–5000 mg L?1 Cl). Removal efficiency substantially varied depending on the element (Cl or Na), the material, and the added NaCl concentration. At the lowest NaCl concentration, Cl removal was higher onto anthracite (48 %) and dolomite (59 %); but greater Na removal was reached onto limestone (54 %) and pozzolan (67 %). At higher concentrations, Cl removal was similar (anthracite), decreased (dolomite), or increased (limestone, pozzolan); and Na removal increased (anthracite) or decreased (dolomite, limestone, pozzolan). Parallel experiments at 4 °C showed lower NaCl removal, anthracite being the most efficient. Practical applicability was evaluated in columns using synthetic runoff solution (NaCl and metals). NaCl removal efficiency was much lower in column assays with respect to batch. The highest NaCl removal was reached onto dolomite, followed by limestone. Metals were successfully removed, generally remaining over time in a wide range (41–89 % Cd, 78–97 % Ni, 44–88 % Cu, and 3–83 % Zn) depending on the material, being pozzolan the least efficient. Further studies including a combination of materials would be of high interest.  相似文献   

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作为21世纪的新兴碳纳米材料,石墨烯具有十分优异的性能,在众多领域中都展现出巨大的应用潜力。煤是储量最丰富、价格最低廉的碳源,且具有独特的结构和物质组成。将煤用于石墨烯等新型碳质材料及其复合材料的开发应用,是一项值得深入探索的工作。煤基石墨烯的发展既能促进煤的洁净利用也能提升煤炭资源的附加值。通过综述分析煤结构研究、煤石墨化机理以及煤基石墨烯研究与制备等方面的发展概况,并提出煤基石墨烯研究的现存问题和未来展望。认为,目前以煤为碳源制备石墨烯及其衍生物的研究尚属于起步阶段,研究的重点是在优化产品制备和性能的方面上,有关煤岩特性对产品质量影响的研究较少。原料煤的结构和物质组成的差异最终会影响煤基石墨烯产品的结构和性能,而煤的结构演变受地质因素影响显著。因此,未来煤基石墨烯的发展应该加强地质作用下的煤原始结构和物质组成对煤基石墨烯产品的影响研究,进而为加快煤基石墨烯研究和提高煤的清洁高效利用提供理论支撑。  相似文献   

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The purpose of this study is to do an experiment in finding conditions of search purification materials and the way of their proper processing for the rapid infiltration method. It seems that this result makes an index of further selection of a purification material. This experiment is to conduct sorption tests of fulvic acid and phosphoric acid regarding Kanuma-soil (volcanic ash soil) with iron oxide and aluminum oxide, to fred relationship between sorption coefficients and heating temperature, concentrations of iron and aluminum. The sorption experiment on heated and unheated materials was conducted at 25℃ in a dark place at the solid to liquid ratio of 1 : 2.5. The liquid is simulated river water. According to the result of the study, a deference was found of the best heating temperature between sorption coefficients of fulvic acid and phosphoric acid. The peak of a sorption coefficient of fulvic acid is 800℃, however the peak of a sorption coefficient of phosphoric acid is 400℃. In the case of fulvic acid, it is high sorption coefficients when Kanuma-soil with aluminum oxide is unheated and heated as 400℃. However, sorption coefficients when Kanuma-soil with iron oxide is not conspicuously different when heated, and coefficients are descended gradually more than 600℃. Sorption coefficients of unheated Kanuma-soil are descended when adding iron oxide. When heating temperature is higher, pH of water is higher. High pH causes to descend sorption coefficient, however it is remarkable result that sorption coefficient is ascended at 800℃. In the case of phosphoric acid, it is high sorption coefficient when Kanuma-soil is heated at 400℃, and Kanuma-soil with aluminum oxide is heated between 200℃ and 400℃. Sorption coefficients of Kanuma-soil with iron oxide are the highest when unheated, but sorption coefficients of Kanuma-soil with iron oxide are the highest when heated.  相似文献   

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西藏达雄群的化石新资料和再认识   总被引:3,自引:2,他引:1  
石和  陶晓风等 《地质通报》2002,21(11):784-786
在达雄群中新发现的双壳Ludbrookiadaxungensis,L.daxungensis,Rasatrixcf.suzulii,Arcticasubextensa及腹足Biplicaobliqu等化石,具早白垩世动物群组合面貌,表明该群的沉积时代大致为早白垩世欧特里夫—阿尔布期(Hauterivian-Albrian),而不是前人划归的中—晚侏罗世,与区内的早白垩世则弄群上部相当。  相似文献   

15.
《Chemical Geology》1999,153(1-4):281-287
An empirical method is presented that allows the determination of the individual contributions of anions and cations to the effect of dissolved salts on hydrogen isotope fractionation in aqueous systems (isotope salt effect). The method is solely based on experimental data and does not involve the choice of arbitrary reference values or theoretical assumptions. Plotting experimental liquid–vapor D/H fractionation factors for aqueous solutions of sodium salts vs. O–D stretching frequencies of water molecules in the hydration shells of the anions shows an excellent linear correlation. The distance between this line and the pure water liquid–vapor fractionation data point in the same plot gives the cation contribution to the isotope salt effects. The anion contribution can then simply be derived as the difference between the total salt effect and the cation salt effect. The validity of the concept is demonstrated using precise literature data for the O–D stretching frequencies in the hydration shells of individual ions at 20°C [Bergström, P.A., 1991. Single ion hydration properties in aqueous solution: a quantitative infrared spectroscopic study. PhD Thesis. Uppsala University] and for the liquid–vapor hydrogen isotope fractionation between aqueous solutions and water vapor at the same temperature [Stewart, M.K., Friedman, I., 1975. Deuterium fractionation between aqueous salt solutions and water vapor. Journal of Geophysical Research 80, 3812–3818]. Within the limits of experimental uncertainties, the data set shows internal consistency. Cation salt effects, 1000 ln Γ at 20°C, are (in per mil per mole per liter, using the convention of Horita et al. [Horita, J., Cole, D.R., Wesolowski, D.J., 1993a. The activity–composition relationship of oxygen and hydrogen isotopes in aqueous salt solutions: II. Vapor–liquid water equilibration of mixed salt solutions from 50–100°C. Geochimica et Cosmochimica Acta 57, 4703–4711]): Na++0.7; K++0.7; Mg2++6.5; Ca2++1.8; Al3++12. The salt effect of H+ cannot be determined unequivocally. The combined effect of the fractionation of H+ itself plus its salt effect is +4.9. Anion effects are +1.4 for Cl, +2.7 for Br, +3.5 for I and −1.4 for SO42. Further single anion salt effects are being predicted as −1.8 for F, +4.9 for NO3, +6.9 for ClO4 and +5.4 for the triflate ion (CF3SO3).  相似文献   

16.
本文研究了东西伯利亚玉矿的开发史。从新石器时代起,东西伯利亚的玉就已成为需求量很大的一种矿物资源。赋存于贝加尔湖区丰富的玉石促进了当地石雕艺技的蓬勃发展。西伯利亚的玉因形成机理迥异而绚丽多彩,该区玉石成因原则上可分为“去超基性岩化型”和“去碳酸岩化型”两种不同类型。东西伯利亚的玉成为重塑当地数千年来文明发展史的标志。文章概述了东西伯利亚的玉在亚洲北部古代社会中和当代科学研究中的重要价值和意义,讨论了该种玉的天然属性对艺术品和工业品制备过程中可能出现的各种问题,展示了东西伯利亚的玉的独特魅力及其与系列化设计工艺品间的差异。  相似文献   

17.
陆相盆地由于纵横向岩性突变和缺乏化石,导致地层划分往往十分混乱。陆相红盆的沉积始终离不开基底母岩的供给。笔者通过剥蚀与沉积的相关性研究实例,来说明其在陆相盆地划分和研究中的实际作用和意义。把盆外母岩的风化剥蚀与盆内堆积的相关性关系研究紧密结合起来,可以极大地提高陆相地层划分的分辨率;同时也有助于加强盆地构造活动的研究。  相似文献   

18.
The potential effects of climatic changes on natural risks are widely discussed. But the formulation of strategies for adapting risk management practice to climate changes requires knowledge of the related risks for people and economic values. The main goals of this work were (1) the development of a method for analysing and comparing risks induced by different natural hazard types, (2) highlighting the most relevant natural hazard processes and related damages, (3) the development of an information system for the monitoring of the temporal development of natural hazard risk and (4) the visualisation of the resulting information for the wider public. A comparative exposure analysis provides the basis for pointing out the hot spots of natural hazard risks in the province of Carinthia, Austria. An analysis of flood risks in all municipalities provides the basis for setting the priorities in the planning of flood protection measures. The methods form the basis for a monitoring system that periodically observes the temporal development of natural hazard risks. This makes it possible firstly to identify situations in which natural hazard risks are rising and secondly to differentiate between the most relevant factors responsible for the increasing risks. The factors that most influence the natural risks could be made evident and eventual climate signals could be pointed out. Only with this information can the discussion about potential increases in natural risks due to climate change be separated from other influencing factors and be made at an objective level.  相似文献   

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