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排序方式: 共有117条查询结果,搜索用时 46 毫秒
1.
Shenggao CHENG Qi AN Jing HU 《中国地球化学学报》2006,25(B08):29-29
Vanadium, improving mechanism and jointing capacity of steel products, is a kind of excellent additive during steel-making and its industry gets support from national industry policy. On account of shallow buried depth and low technique request of exploitation, there is much exploitation by local people lacking system management and technique guidance in area rich in vanadium since years ago, which damages regional environment dramatically. Accordingly, taking stone coal-vanadium as an example, the paper focuses on environment impact on water environment and eco-environment caused by exploitation in open air. Impact of exploitation on surface water mainly includes mining drainage and eluviated water of stock yard. According to civilian exploitation in the area, the rock suffers man-made disturbance, therefore, water quality indicators of mining drainage like heavy metal, permanganate, CI, SO4^2-, F are able to be analogies of ground water quantity in the region since the primary component of drainage is surrounding rock ground water. Water monitoring result of local well shows as follows: pH 6.68, SO4^2- 5.76 mg/L, F- 0.005 mg/L, Fe 0.025 mg/L, Mo 8.08 μg/L, Ni 5.91 μg/L, Co 0.61 μg/L, and all of them reach corresponding standard of water quality. Ground water turns into acid mine water by oxygenation after it discharges and with the help of sulfur the acid water contains nocuous elements which permeate in groundwater and surface water arousing pollution. The value of pH in the range of standard indicates that the acidification of mine water is relatively weak in the diggings. Eco-environment damage is another aspect that cannot be ignored, it acts as: (1) peeling work and establishment construction destroy landform; (2) stack of waste soil and rock occupies amounts of land; (3) various exploitation activities like vegetation peeling, landform change will enlarge the scope or enhance the intensity of soil erosion, which destroys eco-environment by leading water and soil loss; 相似文献
2.
Yaping WANG Chunxue XU Ziyi AN Suming WANG 《中国地球化学学报》2006,25(B08):205-205
Different species of one element have different activities, so it has different effects on environment and human health. To analyze qualitatively and quantitatively the speciation of a special element in sample, which is the important basis for appraising the toxicity and studying the rule of transfer and translation of elements. Since the 1970's, the scheme of sequential extraction has already been used at many laboratories both at home and abroard, to get the information about heavy metals' activity in polluted soils. Because this method has the experimental nature, many schemes of problem has taken place, the absence of consistency of these sequential extraction have been formed. Thus the complexity of the schemes, the lack of selectivity of reagent, the lack of quality control, the result mainly related to the extraction scheme used, and so on. In the face of these problems, the study of experimental methods of sequential extraction on three different soils, sediment in Dongting Lake, soil in Jiangsu Province and loess in Shanxi Province was made. Reference materials of heavy metal speciation following sequential extraction in soil and sediment had been developed. Nowadays two kinds of sequential extraction methods which are widely used are BCR (three steps) and improved Tessier methods (seven steps). Based on three steps of BCR, water-soluble speciation and the residual speciation were increased in our research. BCR701 was determined eight times at different laboratories using BCR three steps. The results showed that determined data obtained eight times were identical to the standard value, and it is indicated that this method has good reproducibility. The stability and homogeneity experiments indicated that the preparation of three types of candidates accorded with our requirements. Eight laboratories had afforded the determined values of 12 heavy metal elements (Cu, Pb, Zn, Mn, Co, Ni, Cd, Cr, Mo, As, Sb, Hg, Se et al.) using BCR three steps. Also, these three candidates afforded the determined values by seven steps, and 12 laboratories had participated. 相似文献
3.
The geography information system of the 1303 Hongton M=8 earthquake has been established. Using the spatial analysis function of GIS, the spatial distribution characteristics of
damage and isoseismal of the earthquake are studies. By comparing with the standard earthquake intensity attenuation relationship,
the abnormal damage distribution of the earthquake is found, so the relationship of the abnormal distribution with tectonics,
site condition and basin are analyzed. In this paper, the influence on the ground motion generated by earthquake source and
the underground structures near source also are studied. The influence on seismic zonation, anti-earthquake design, earthquake
prediction and earthquake emergency responding produced by the abnormal density distribution are discussed.
Foundation item: National important fundamental research “The Basic Research of Important Project in Damage Environment” and The important
project “The Seismic Hazard Assessment Research and Anti-earthquake Structure Research” from China Earthquake Administration
during the 10th Five-year Plan.
Contribution No. 04FE1008, Institute of Geophysics, China Earthquake Administration. 相似文献
4.
Identification of Greigite in the Pliocene Sediments of Qinghai Lake and Its Geological Significance
正Objective The Qinghai Lake in North China is the largest interior plateau lake in Central Asia,and is sensitive to climate change and the environmental effects of Tibetan Plateau uplift.An almost continuous 626 m long sediment core was drilled in an in-filled part of the southern lake basin in the Scientific Drilling at Qinghai Lake.Previous 相似文献
5.
6.
THEFLUCTUATINGCHARACTERISTICSOFHYDRODYNAMICFORCESONBEDPARTICLE¥WANGXingkuiandANFengling(TheFinancewasSupportedbyNationalScien... 相似文献
7.
Please?refer?to?the?attachment(s)?for?more?details. 相似文献
8.
Saishitang Cu-polymetallic deposit is located in the southeast section of Late Paleozoic arcfold in the southeastern margin of Qaidam platform. Accoring to the geological process of the deposit,four mineralization episodes were identified: melt/fluid coexisting period(O),skarn period(A),first sulfide period(B) and second sulfide period(C),and 10 stages were finally subdivided. Three types of inclusions were classified in seven stages,namely crystal bearing inclusions(type I),aqueous inclusions(type II) and pure liquid inclusions(type III). Type I and II inclusions were observed in stage O1,having homogenization temperature from 252 to 431°C,and salinities ranging from 24.3% to 48.0%. Type I inclusion was present in stage A1,having homogenization temperature from 506 to 548°C,and salinities ranging from 39.4% to 44.6%. In stage B1,type II and III inclusions were observed,with homogenization temperature concentrating between 300–400°C,and salinities from 0.4% to 4.3%. Type II inclusions were present in stage B2,with homogenization temperature varying from 403 to 550°C. In stage C1,type I and II inclusion commonly coexisted,and constituted a boiling inclusion group,having homogenization temperatures at 187–463°C,and salinities in a range of 29.4%–46.8% and 2.2%–11.0%. Type II and III inclusions were developed in stage C2,having homogenization temperature at 124–350°C,and salinities ranging between 1.6% and 15.4%. In stage C3,type II and III inclusions were presented,with a homogenization temperature range of 164–360°C,and salinities varying from 4.0% to 11.0%. The results of micro-thermal analysis show that fluids are characterized by high temperature and high salinity in stage O1 and A1,and experienced slight decrease in temperature and dramatic decrease in salinity in stage B1 and B2. In stage C1,the salinity of fluid increased greatly and a further decrease of temperature and salinity occurred in stage C2 and C3. Fluids boiled in stage C1. With calculated pressure of 22 MPa from the trapping temperature of 284–289°C,a mineralization depth of 2.2 km was inferred. Results of Laser Raman Spectroscopy show high density of H2 O,CH4 and CO2 were found as gas composition. H-O isotope study indicates the oreforming fluids were the mixture of magmatic water and meteoric water. Physicochemical parameters of fluids show oxygen and sulfur fugacity experienced a decrease,and redox state is weakly reducing. Along with fluid evolution,oxidation has increased slightly. Comprehensive analysis shows that melt exsolution occurred during the formation of quartz diorite and that metal elements existed and migrated in the form of chlorine complex. Immiscible fluid separation and boiling widely occurred after addition of new fluids,bringing about dissociation of chlorine-complex,resulting in a great deal of copper precipitation. In conclusion,Saishitang deposit,controlled by regional tectonics,is formed by metasomatism between highly fractionated mineralization rock body and wall rock,and belongs to banded skarn Cu-polymetallic deposit. 相似文献
9.
WU Quan-yuan AN Guo-qiang BAO Wen-dong ZHANG Zu-lu XU Qiu-xiao FANG Xue-mi 《中国地理科学(英文版)》2005,15(4):355-360
1 IN T R O D U C T IO NZhaoyuan C ity, located in northeast of ShandongProvince,iscalled "G old C ity"and itisone ofim portantgold production bases in C hina.The exploitation ofthegold broughtoutthe extensive vacantareas,leading tolarge-scale ground subsi… 相似文献
10.
西藏班公湖-怒江板块结合带岩金遥感找矿模式 总被引:1,自引:0,他引:1
西藏班公湖-怒江板块结合带地质构造复杂,成矿条件优越,具备形成金矿的地质背景条件,是西藏最具潜力和规模巨大的贵金属成矿带.但由于该区地质工作程度较低和对成矿规律认识不清,至今没有一个可供开发的岩金矿产地.通过班公湖-怒江板块结合带砂金、岩金矿(化)点,地球化学异常和重砂异常的分布并进行控矿因子分析,建立了该带两种岩金遥感找矿模式,通过验证发现该区具有大型远景规模的岩金矿产地,并认为蚀变岩型金矿和穆龙套型金矿是该带最重要的两种矿床类型,具有巨大的找矿潜力. 相似文献