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1.
吉林省地矿局科技处受吉林省白河林业局的委托,在长白山天池附近找到一处优质“天池麦饭石”。该麦饭石是在调查寻找七处矿点中优选出来的。出露范围有0.5km~2,其质地优良,富含 Mo、Se、Cr、Cu、Zn 等对人体有益元素,且溶出量高;原岩有害元素 Pb 最低,As、Cd、Hg 也均低,且溶出量也很低;生物毒理试验效果较佳。各项指标均可与中华麦饭石、阜新麦饭石及我省凤栖、长白麦饭石比美。该项资源是经地学、医学、卫生等十位行业专家共同鉴定确认的。并认为其研究程度较高,具有国内同类研究的先进水平。  相似文献   

2.
冀东平原土壤中重金属元素的地球化学特征   总被引:4,自引:3,他引:1  
通过分析冀东平原土壤中有害重金属元素Pb、Cr、Cd、As、Hg的含量变化特征,显示有害重金属元素Hg、Cd、Pb在冀东平原表层土壤的富集已较为明显,Cr、As也形成局部的异常,原有的地球化学特征发生较大变化。初步认为表层土壤中重金属元素的高含量与当地地质背景和人为活动有关,局部异常成因需要进一步研究。研究区地积累指数污染评价结果表明:以全国土壤背景值计算,重金属未造成污染;以研究区背景值计算,Hg表现为轻度—中度污染状况,As、Cd、Cr、Pb未造成污染。  相似文献   

3.
矿物材料与环境污染治理—以粘土矿物和沸石为例   总被引:9,自引:0,他引:9  
矿物的性能,矿区地质测试和吸附能力实验表明,粘土矿物和沸石等矿物材料对于Cr,Cd,Pb,Hg,As等有害元素具有很强的吸附能力,是理想的低成本吸附剂,在废水处理中可用来取代活性炭或离子交换树脂来去除重金属等有害元素。  相似文献   

4.
利用1∶25万土地质量地球化学调查数据分析和研究了安徽省宣城市南部地区土壤中As、Cd、Cr、Cu、Hg、Ni、Pb、Zn 8种重金属元素的地球化学特征以及重金属异常来源。调查发现地质背景是土壤元素含量的主控因素,调查区表、深层土壤重金属元素含量空间分布特征与地质背景、沉积环境表现出显著的空间一致性,重金属高含量成土母岩(荷塘组、皮园村组、蓝田组等地层)是土壤重金属元素高异常的主要影响因素,此外矿山开采、大气干湿沉降也是土壤重金属高异常的影响因素之一,土壤中Pb、Hg、Cd、Cr元素具有大气干湿沉降的输入来源。调查区土壤重金属污染风险主要影响指标为Cd,土壤Cd超过农用地土壤污染风险管制值的样品比例为2.56%,形态分析结果显示土壤Cd以离子交换态为主,结合农作物调查发现在土壤Cd高异常区存在一定的生态风险。  相似文献   

5.
《地下水》2017,(6)
通过测量神木北部矿区及其毗邻地区2种土壤类型(风沙区和黄土区)下8种重金属(As、Cd、Cr、Hg、Pb、Cu、Zn、Ni)元素含量,评价矿区整体土壤重金属污染情况。结果表明:研究区2种土壤条件下除Pb和Cd外,其他6种重金属含量较毗邻未开采区具有显著增加,但8种土壤重金属含量均没有超过国家土壤环境质量二级标准;风沙区土壤污染程度较黄土区大;重金属元素污染分担率表现为HgZnAsCuNiCrPbCd;Hg、Zn和Cr 3种元素在两种土壤类型中均为重度污染,As、Cu和Ni属于中轻度污染,Cd和Pb属清洁安全类。  相似文献   

6.
基于表层土壤、中药材及根系土等样品的测试数据,研究了赤峰市锡伯河流域牛家营子镇中药材种植区表层土壤As、Cd、Cu、Hg、Pb五种重金属元素的含量、空间分布特征、污染程度及不同中药材对土壤重金属元素的累积特征和草药重金属污染程度.结果表明,中药材种植区表层土壤As、Cd、Cu、Hg、Pb五种重金属元素成因来源一致,为伴生关系,主要来自成土母质,其含量均值分别为8.729×10-6、0.142×10-6、21.146×10-6、0.036×10-6、23.651×10-6;Hg、Cd元素变异系数分别为0.639、0.472,达到强度变异,原因是二者土壤本底含量较低,更易受到各种因素影响.土壤重金属单项和综合污染指数均小于0.7,土壤质量清洁,符合中药材GAP基地建设土壤环境要求.桔梗、北沙参和牛膝3种中药材药用部位重金属富集系数或污染指数均小于0.50,其含量都远低于中药材重金属含量限定值,牛家营子镇中药材种植区产出的中药材均符合绿色行标要求.  相似文献   

7.
北京平原区元素的大气干湿沉降通量   总被引:8,自引:0,他引:8  
从2005年11月到2006年11月,采用被动方式同时采集了北京市平原区10个地点的大气干、湿沉降样品共计39件.分析干、湿沉降样品中K、Na、Ca、Mg、Cd、Hg、Pb、As、B、Mo、Mn、Zn、Cu、Cr、Ni元素的含量,分别计算出各元素的年沉降通量.其中,有害金属元素Cd、Hg、Pb、As的年沉降通量的平均值分别为2.36、0.24、219.95、29.00(g/hm2·a).对比后发现,研究区大气Cd和Hg的年输入通量远远低于四川成都经济区,Cd和Hg的大气污染状况相对南方地区较轻,As和Pb的年输入通量相对成都经济区差异较小.研究区元素的大气沉降通量与同点位的土壤元素的相关分析表明,元素的沉降通量并不是农田生态系统中土壤元素的主要输入途径,大气沉降中的元素主要来自远源.  相似文献   

8.
山东省东部地区土壤地球化学特征及污染评价   总被引:1,自引:1,他引:0       下载免费PDF全文
以山东省东部地区农业生态地球化学调查取得的区域土壤地球化学数据为依据,研究了区内54种元素或指标的土壤地球化学基准值和背景值与全国土壤的差异。通过对比区内土壤基准值与背景值的变化,认为本区大部分元素或指标在表层土壤中的含量继承了成土母质,后期人类活动对其影响较小,Zn、Pb、Cu、Se、Cd、S、P、Hg、N、OrgC等元素或指标在表生作用或人类活动等因素影响下,其分布分配特征产生明显变化。本文通过对表层和深层土壤元素相关系数的研究,认为深层土壤元素地球化学含量可表征表层土壤原始沉积的地球化学含量;讨论了人为活动导致土壤污染的评价方法,莱州—招远—烟台和牟平—乳山金矿集中区以及人口密集的城镇地带表层土壤中Hg、Cd、Pb、As、Zn、Se、S等元素污染严重。地质背景和人类活动(采金污染、工业生产、城市人口密集生活等)的共同作用,是造成环境中有害元素含量较高的主要原因。  相似文献   

9.
沈阳市新城子区土壤重金属元素的空间变异性   总被引:4,自引:1,他引:4  
利用地质统计学方法,系统地研究了沈阳市新城子区土壤重金属元素的空间分布及空间变异性特征。研究结果显示,土壤中Cd和Pb的含量明显高于全国平均值和辽宁省土壤背景值。变异函数分析结果表明,Hg具有明显的空间自相关性,Cd、Pb和As均具有中等空间自相关的特征。Cd和Pb含量较高,并呈显著的正相关,主要受灌溉、施肥等外在因素的影响。重金属元素空间变异性的研究对当地土壤环境评价和土地质量评估具有一定的指示和引导作用。  相似文献   

10.
太原盆地土壤微量元素的地球化学特征   总被引:17,自引:1,他引:16  
文章分析了太原盆地土壤微量营养元素Fe、Mn、Cu、Zn、Mo、B和有害重金属元素As、Cd、Cr、Hg、Pb的含量变化特征.太原盆地土壤中微量营养元素与世界土壤和全国土壤的平均值相比趋于缺乏状态,而高于全国黄土和山西省土壤的平均含量.有害重金属元素在太原盆地表层土壤的富集已较明显,原有的地球化学特征已发生较大变化.Hg、Cd、Pb对环境的危害作用应引起重视.  相似文献   

11.
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.  相似文献   

12.
本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。  相似文献   

13.
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提  相似文献   

14.
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.  相似文献   

15.
Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.  相似文献   

16.
本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。  相似文献   

17.
岩石密度和超高压岩石折返速率   总被引:1,自引:3,他引:1  
在常温常压条件下对中国大陆科学钻CCSD主孔100-3000米岩心样品进行了密度测量,建立了密度连续剖面,并界定了不同超高压岩石的密度值。通过对比高温高压物性实验资料,岩石密度随着退变程度增强而降低,榴辉岩密度变化序列为3.52g/cm3→3.49g/cm3→3.07g/cm3→2.93g/cm3。超高压长英质岩石密度变化序列为3.00g/cm→2.80g/cm3→2.65g/cm3。上述实验资料是讨论不同折返阶段岩石所受浮力的基础,为研究折返速率大小提供了基本参数。本文通过折返板块运动平衡时,上浮力与粘滞力平衡这一关系式,定量研究了大陆俯冲板块的折返速率,认为密度差产生上浮力从而引起折返,温度对板块折返速率的影响最为显著;密度差大小、折返角度、折返板块大小对折返速率也有直接的影响。定量模拟分析表明,在温度高于850℃时,板块的折返速率可以超过100mm/a;当温度降至700℃时,折返速率则低于1.5mm/a。作者认为在折返早期,温度较高,板块快速折返至60-70km榴辉岩相深度;随着传导散热,温度降低,板块以较慢的速率折返至中下地壳。折返速率的估算表明,浮力是板块折返第一阶段(从>100km深部折返至<40km的中下地壳)的主要驱动力。  相似文献   

18.
Bellechester, Minnesota, is a small community of approximately 155 residents located on the county line between Goodhue and Wabasha counties in southeast Minnesota's karst region. Bellechester is served by a 21-year-old wastewater treatment facility (WWTF) consisting of three waste-stabilization ponds. On 28 April 1992 six sinkholes were discovered to have drained cell 2 of the WWTF resulting in the loss of approximately 8.7×106 1 of partially treated effluent and about 600 m3 of soil into previously undetected subsurface voids of unknown dimensions. In the week following the collapse, approximately 200 water wells located within a 5-km radius of the WWTF were sampled in an after-the-fact, emergency sampling program. Twelve samples with elevated fecal coliform levels, 18 samples with nitrate-nitrogen greater than the 10 mg/1 standard, and no samples with elevated chlorides were found. However, the elevated levels could not be unambiguously attributed to the WWTF collapse. This is the third WWTF to fail by sinkhole collapse in southeast Minnesota since 1974. All three collapsed lagoons have been located in similar geomorphic and stratigraphic settings. However, at least two lagoons have collapsed in the adjacent area in northeast Iowa, and these lagoons are located at different stratigraphic positions. Twenty-two WWTFs constructed in southeast Minnesota's karst region in the last 25 years have been identified as subject to potential sinkhole collapse. An unknown but significant number of manure storage lagoons, flood control structures, etc., have also been constructed in the karst region and are at risk. Public agencies are beginning to develop plans to deal with the risk associated with existing and future waste lagoons in this environment. The critical hydrogeologic parameters that can be used to prioritize the risk of collapse at existing facilities include: (1) the lithology of the first bedrock beneath each lagoon, (2) the thickness of surficial materials between the lagoon and the bedrock surface, (3) the presence and construction of liners (seepage rate), and (4) the proximity to existing sinkholes.  相似文献   

19.
The Kuskokwim River at Bethel, Alaska, drains a major mercury-antimony metallogenic province in its upper reaches and tributaries. Bethel (population 4000) is situated on the Kuskokwim floodplain and also draws its water supply from wells located in river-deposited sediment. A boring through overbank and floodplain sediment has provided material to establish a baseline datum for sediment-hosted heavy metals. Mercury (total), arsenic, antimony, and selenium contents were determined; aluminum was also determined and used as normalizing factor. The contents of the heavy metals were relatively constant with depth and do not reflect any potential enrichment from upstream contaminant sources.  相似文献   

20.
滇东南锡、银、铅、锌多金属矿床主要分布在个旧、白牛厂、都龙3个矿区,而滇东南较大的3个花岗岩体又分别出露在3个矿区或附近.花岗岩体均形成于燕山晚期,岩石化学、矿物成分相似,富含锡、银、铅、锌、钨、铜等成矿元素.矿床主金属元素组合与岩体之间的距离由远而近出现由锡、钨、(铍、铌、钽)→锡、钨、(铁)、铜、铟→锡、铅、锌、银、铟、(锑)有规律的变化.花岗岩浆是成矿物质来源和成矿热源.岩浆侵入初期使上覆地层隆起产生背斜(凹陷部位成向斜);同时使地层产生一系列裂隙、压性断层或层间断裂;岩浆侵入晚期,这些断层再次活动,表现为张性,岩浆产生的含矿热液沿由其活动所造成的断裂迁移、充填、交代、沉淀而形成矿床.  相似文献   

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