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针对自然降尘、工业区降尘及人工粉尘进行的物相、成分、表面形貌、元素含量和粒度分析表明降尘均以石英和方解石为主要物相成分,SiO2、CaO含量较高,K2O、Na2O含量低。自然降尘为无规则颗粒,大颗粒表面上带有微小颗粒团聚;工业区降尘形貌呈球形、团状;人工粉尘呈柱状或纤维状。降尘粒度在0.3~5μm内集中分布,小于5μm的粉尘比例均超过99%。在模拟人体温度37℃条件下,进行了32 h内粉尘在谷氨酸水溶液中的溶出行为和电化学作用的对比研究。各粉尘样品的pH值和电导率变化趋势相似,8 h前各粉尘样品的pH值电导率随时间增加缓慢上升,8 h到32 h间pH值上升速度明显加快。元素K、Ca、Na、Mg的溶出离子总量为35.4~429 mg/L,其中Ca元素的溶出量最大为20~334 mg/L,重金属离子Fe、Zn、Mn、Pb、Ba的离子溶出总量为0.18~5.59 mg/L,Al、Si离子溶出总量为3.0~21.7 mg/L。粉尘中各元素主要在前16 h溶出较快。各粉尘在酸性谷氨酸水溶液中的溶解程度由大到小为:硅灰石蛇纹石海泡石;水泥厂降尘自然降尘电厂降尘。CaO含量高的水泥厂降尘和硅灰石人工粉尘溶解程度最大,表明其在酸性谷氨酸环境中耐腐蚀性较差,表现出较低的生物持久性。SiO2含量高的电厂降尘和海泡石人工粉尘溶解程度最小,具有较强耐蚀能力和较高生物持久性。 相似文献
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以西宁降尘为研究对象,探讨柠檬酸溶解2 d过程中体系的pH及电导率变化,借助XRD、FTIR、SEM和ICP等表征手段,对降尘经酸处理后的残余固体及上清液进行分析。降尘加入柠檬酸的前4 h,反应溶液pH迅速上升;电导率从初始的4.31 ms/cm迅速升高到5.61 ms/cm,然后缓慢下降;8 h后,pH和电导率基本达到稳定。根据XRD分析,白云石特征峰(d=0.2886 nm、0.2190 nm等)和方解石特征峰(d=0.3031nm、0.2282 nm等)完全消失;根据红外分析,代表碳酸盐矿物的特征峰(1430 cm-1和877 cm-1)也消失,结合XRD结果可以得出方解石和白云石在柠檬酸作用2 d后完全溶解。柠檬酸溶出了降尘中大量的Ca2+,K+,Mg2+,Fe3+,Al3+,Si等元素,其中Ca2+的溶出量达到711.63 mg/L。柠檬酸对不同元素溶出的促进作用由强到弱依次为:FeAlSiCaMgK。在柠檬酸的作用下,降尘中的矿物被全部或部分溶解,其中碳酸盐矿物几乎完全溶解。 相似文献
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周口店地区的古环境变化研究多数研究集中在中更新世时期,而缺乏对早更新世时期环境变化的研究。这主要是由于缺少保存完好的早更新世沉积记录造成的。随着对20世纪80年代在周口地区发现的东洞剖面,发现这是一个保存完好的早更新世剖面,为研究早更新世时期的古环境变化特征提供了良好的研究材料。为了重建早更新世时期的古环境变化特征,利用XRF对东洞洞穴沉积物的主要元素（SiO2,Al2O3,Fe2O3和CaO）的化学组成进行了高分辨率分析,同时对沉积物中的FeO含量进行了测试。结果显示东洞剖面沉积物的主要化学组成为SiO2,占41.6%～58.9%,其次是Al2O3和Fe2O3,其含量的变化范围分别为13.69%～29.63%和5.00%～9.81%。Al2O3和Fe2O3在剖面上与SiO2含量成明显的镜像变化关系,显示出Al2O3和Fe2O3对沉积物中SiO2含量的稀释作用。另外,Fe2O3与Al2O3在剖面上具有很好的相关性,表明Fe2O3主要富集在富铝的矿物中。从元素含量在剖面的上分布看,东洞剖面的化学组成发生3次大的波动,主要表现为SiO2和FeO含量增高,而Fe2O3与Al2O3含量的减少。这3次波动分别出现在剖面的15.3～14.6m,11.0～9.9m和8.40～7.84m深度处。在3次化学组成的波动出现的同时,指示沉积物风化程度和温度变化的Si/Al（SiO2/Al2O3）和FeO/Fe2O3比值也发生了明显变化,比值增高,指示了3次大的干冷事件。另外,在剖面上部（10.00～7.84m,即第2次事件以后）SiO2/Al2O3和FeO/Fe2O3比值变高且波动频繁,表明自第2次干冷事件后沉积区的环境变得不稳定,逐渐向冷干气候转变。东洞剖面的地球化学记录（SiO2/Al2O3和FeO/Fe2O3）与泾川黄土剖面的粒度曲线具有较好的对比性,支持了东洞剖面记录的环境信息与黄土沉积记录的环境变化具有一致性。通过与泾川粒度曲线的对比发现,东洞剖面记录的3次干冷事件在时段上分别对应于黄土-古土壤序列中的L26,L15和L13。 相似文献
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基于XEPOS型X射线荧光光谱仪研究江西朱溪铜钨矿床成矿元素地球化学特征与成因 总被引：1，自引：1，他引：0
江西朱溪铜钨矿是近年新发现的一个以钨铜为主的多金属大型至超大型矿床,成矿潜力巨大,但目前仅对矿床地质特征等有所研究,研究程度较低,因此急需对矿床成因类型、地球化学特征等进行深入研究。本文对铜钨矿体钻孔岩芯样品进行直接粉末制样,应用XEPOS型偏振激发能量色散X射线荧光光谱仪分析主量元素(SiO2、CaO、MgO),微量元素(Cu、W、Zn、Ag)的含量,研究朱溪矿区成矿元素的地球化学特征。结果表明,主量元素SiO2、CaO、MgO交代作用显著,SiO2和CaO呈"对顶"之势;微量元素Cu、W、Zn、Ag等含量随深度增加呈波状起伏是受构造控制的岩层交代的明显特征,且Cu、W在空间上有中间高、两边低的分布特征。这些元素的变化趋势均表明该矿体属于交代成因,而元素的变化反映到矿物组合也说明成矿物质来源与花岗岩、花岗斑岩、花岗岩闪长岩等有关。本文的研究成果可为进一步勘探工作与成矿预测提供理论依据。 相似文献
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【研究目的】近年来,随着生活水平的不断提高,人们对健康饮水的要求也在不断提高,寻找与开发富含H2SiO3等矿物质优质地下水已成为关键。【研究方法】本文以昭觉地区水文地质调查工程、地下水污染调查工程所获取的地下水化学数据为基础,探讨了昭觉地区富H2SiO3地下水的分布特点、元素水文地球化学特征、形成条件及成因。【研究结果】结果显示：（1）全县富H2SiO3（≥25 mg/L）地下水均属于低矿化度偏碱性水,分布在基底岩石为玄武岩的6个片区,H2SiO3含量一般介于25.74~46.04 mg/L,pH含量一般介于7.4~8.58,TDS含量一般介于49.4~333 mg/L;（2）玄武岩地下水存在HCO3－Ca、HCO3－Ca·Mg、HCO3－Ca·Na、HCO3－Ca·Mg·Na、HCO3－Na等5种水化学类型,总体以HCO3－Ca · Mg为主,其次为HCO3－Ca,再次为HCO3－Ca · Na,三者分别占总采样点数的50.00%、25.76%、12.12%;（3）全县富H2SiO3地下水的形成受水岩相互作用、硅酸盐矿物的分布范围及其可溶性、围岩裂隙发育程度、水源涵养及补给条件等四方面因素影响,其中水岩相互作用占据主导作用;（4）在后续开发利用过程中,需进一步揭示影响地下水中H2SiO3分布与迁移的因素。【结论】研究结果可以为昭觉地区矿泉水产业的发展及城乡优质水源地的建设提供依据。创新点：系统总结了昭觉县优质偏硅酸地下水空间分布特征和水化学特征;从形成条件与水岩作用的角度探讨了优质偏硅酸地下水的形成机制。 相似文献
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为了研究泉水化学成分特点和在一年内的变化,文章利用pH-电导率自动记录仪对陕西秦岭翠华山地区两处泉水化学成分进行了每月2次的观测,并进行了水化学分析。翠华山泉水中HCO-3含量在76.27～152.55mg/L之间,Ca2+含量在14.48～26.92mg/L之间,Mg2+含量在4.46～4.89mg/L之间,K+含量在0.60～2.75mg/L之间,Na+含量在0.93～1.09mg/L之间,这些成分的特点是含量低。泉水pH值在6.98～5.69之间,夏秋季低于该区雨水的pH值,具酸性特征,这是该区地层主要由片麻岩构成决定的。从1月到11月,水秋池村泉水pH值和电导率呈现由大到小再到大的变化规律,引起这种变化的主要原因是夏秋季土壤CO2含量比冬春季高,泉水在夏秋季流动过程中吸收了较多的CO2。翠华湖西泉水pH值和Ca2+,Mg2+,K+,Na+离子含量比水秋池泉水高,从1月到11月Ca2+,Mg2+,K+,Na+离子含量变化与水秋池泉水变化相反,这应当是两个泉水的来源不同或在流动过程中遇到了酸碱性不同的土层和地层造成的。翠华山地区泉水化学成分变化是易于观测到的规律性很强的变化。 相似文献
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基于成渝地区土地质量地球化学调查资料,研究四川南部县土壤中54种元素的地球化学特征。结果表明,与全国土壤相比,研究区重金属元素As、Cu、Hg、Pb、Zn基准值较低,Cd、Cr较高,Ni相当;多数重金属元素和植物营养元素背景值低于全国A层土壤背景值,仅CaO、Cd、MgO、Cr、F等的背景值高于全国土壤水平。多数元素(指标)背景值与基准值相当,说明表生作用和人为活动对表层土壤影响较小;而C、CaO、Cd、Org.C、I、MgO、N、P、S、Se等10种元素(指标)在表层土壤富集,表明这些元素受自身地球化学行为和人为活动输入影响。第四系和侏罗系遂宁组地层表层土壤元素分布差异较大,富集或贫化特征明显。就pH值而言,Cd、F、Cl、Mn、N、P、K2O、S、CaO、C、Org.C均在碱性环境含量较高,As、Cr、Cu、Ni、Pb、Zn、Co、B、Mo、Ge、TFe2O3、SiO2在酸性环境含量高,多数元素在中性环境中趋于稳定。 相似文献
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海泡石化学成分分析标准物质研制 总被引：2，自引：0，他引：2
海泡石是一种十分重要的非金属矿，被广泛应用于航空、畜牧、化工环保等领域中，贸易活动十分活跃。鉴于中国一直没有海泡石标准物质，国际上的海泡石标准物质定值组分少，为了满足相关研究需求，本文研制了湖南湘潭的海泡石标准物质（GBW07138）。对Ba、Be、Bi、Cd、Ce、Co、Cr、Cs、La、Li、Lu、U、Nb、Nd、Ni、Pb、SiO2、Al2O3、Fe2O3、MgO、CaO、Na2O、K2O、TiO2共24种组分进行均匀性和稳定性检验。针对不同含量、不同性质的组分，采用合理的国家标准方法检验了20种组分的RSD小于3%，其余4种组分Bi、La、Lu、Mo的RSD略大于3%，方差检验的F值均小于列表临界值[F0.05（29，60）=1.65]，表明该标准物质均匀性良好。在稳定性考察期内，24种组分的含量无统计学上的明显变化，表明该标准物质稳定性良好。由9家实验室采用重量法、容量法、X射线荧光光谱法、电感耦合等离子体质谱法等传统化学分析方法和现代仪器分析方法协作定值，最终定值组分63种，涵盖了主量、微量及全部稀土元素，其中海泡石特征组分MgO和烧失量（LOI）的含量分别为18%±0.2%和8.55%±0.19%，这两种组分与现有的标准物质形成一定阶梯性，能够更好地满足海泡石成分分析测试需求。该海泡石标准物质可用于地质找矿、地球化学调查、地质矿产产品测试以及其他行业相关领域样品测试的质量监控标准。而且在研制该标准物质过程中，改良或开发的一些新方法可为后续开发海泡石标准物质提供技术支持。 相似文献
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中祁连西段苏里地区有大量北东和近东西向延伸的辉绿岩、辉长岩呈岩墙状侵入到元古宙地质体中。基性岩墙的SiO2含量为46.77%～52.37%,Al2O3含量为12.82%～15.86%,TiO2含量为1.16%～3.14%,MgO含量为3.84%～7.98%,FeOT含量为10.42%～15.53%,以贫K2O （0.10%～1.60%）、Na2O>K2O为特征,里特曼指数σ=0.67～2.96,岩石主量元素地球化学成分与大洋拉斑玄武岩一致;全岩稀土元素总量较低（51.28×10-6～165.11×10-6）,轻重稀土元素之比为2.67～4.90,（La/Yb）N值为2.04～5.03,属轻稀土元素富集型,δEu=0.93～1.12,无明显的Eu异常;富集Rb、Ba、Th、U,亏损Nb和K,大离子亲石元素丰度变化范围相对较宽,高场强元素富集程度不强,微量元素蛛网图上具有左侧隆起、右侧相对平坦的分布型式。基性岩墙LA-ICP-MS锆石U-Pb年龄为819.5±5.2 Ma,形成时代与全球性Rodinia超级大陆裂解时代高度一致。岩石地球化学分析结果显示岩浆起源于亏损地幔源区,是尖晶石地幔橄榄岩部分熔融的产物,岩浆形成于陆内裂谷环境,表明其可能为Rodinia超级大陆裂解的产物。 相似文献
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《Applied Geochemistry》2001,16(11-12):1361-1368
Due to rapid urbanisation and scarcity of land, most of the urban parks and recreational areas in Hong Kong are built close to major roads or industrial areas, where they are subject to many potential pollution sources, including vehicle exhaust and industrial emissions. An extensive soil survey was conducted in urban parks of Hong Kong to study the current conditions of heavy metals contamination in soils. Soil samples and associated street dusts were collected from more than 60 parks and public amenity areas in old urban districts, industrial areas and New Towns of the territory. Soils were also sampled in the remote country parks to establish the baseline conditions. The total concentrations of heavy metals and major elements in the samples were determined. The results indicate that urban soils in Hong Kong have elevated concentrations of Cd, Cu, Pb and Zn. The parks with high metal concentrations are located in old urban commercial districts and industrial areas, indicating that the major contamination sources in these soils are traffic emissions and industrial activities. In addition, the application of Cd containing phosphate fertilizers may be an important source of Cd in urban park soils. The street dusts have highly elevated Zn concentration, particularly along the main trunk roads. The high Zn content in the street dusts may come from traffic sources, especially vehicle tyres. Selective soil and road dust samples were also analysed for potential chemical speciation by a sequential chemical extraction method. The chemical partitioning results show that Pb and Zn are mainly in the carbonate/adsorbed and Fe–Mn oxide phases, while Cu is largely associated with the organic and sulphide fractions. The high exchangeable Cd in urban soils and high concentration of Zn in street dusts need further investigation for their ecological and health implications. 相似文献
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大气粉尘中的矿物及其环境健康效应研究进展 总被引：3，自引：0，他引：3
大气粉尘中的矿物主要来源于土壤尘、建筑工地和局地扬尘,颗粒较小,一般呈不规则形状,表面凹凸不平。矿物粉尘具有很强的生物活性,对人体健康、生物效应有其特有的生理作用。矿物粉尘表面活性基团影响粉尘的生物效应。矿物粉尘本身或刺激吞噬细胞而产生的自由基对细胞的损伤和粉尘性疾病的形成起着至关重要的作用。大气粉尘成分、表面特性以及矿物粉尘对人体正常宿主菌群的抑制性和毒性效应研究是矿物粉尘环境健康效应研究的重要方向。 相似文献
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大冶市街尘重金属污染评价及化学形态特征 总被引：3，自引：0，他引：3
以矿冶城市大冶市为例,结合街尘pH及矿物相,研究矿山活动影响下的2个典型区(靠近矿区的铜绿山镇和相对远离矿区的大冶市区)街尘中重金属(Cd、Pb、Cu)污染现状及化学赋存形态.地累积指数显示,铜绿山镇重金属处于严重污染水平,大冶市区处于重污染水平,其中Cd和Cu相对于Pb污染较严重.重金属BCR形态表明,铜绿山镇Cd以可氧化态和可还原态为主,大冶市区Cd四态比例基本相同;Pb在铜绿山镇以残渣态和可氧化态为主,而在大冶市区以弱酸态和可氧化态为主;Cu在两研究区均以可氧化态为主.Pb和Cd生物活性较大,对环境危害较高,Cu相对较低. 相似文献
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Yongming Han Junji Cao Eric S. Posmentier Kochy Fung Hui Tian Zhisheng An 《Applied Geochemistry》2008
Sixty five urban road dust samples were collected from different land use areas of ∼240 km2 in Xi’an, China. The concentrations of Ag, As, Cr, Cu, Hg, Pb, Sb and Zn were determined to investigate potentially harmful element (PHE) contamination, distribution and possible sources. In addition, the concentrations in different size fractions were measured to assess their potential impact on human health. The highest concentrations were found in the fraction with particle diameters between 80 μm and 101 μm, the finest particles (<63 μm) were not the most important carriers for Ag, As, Cd, Cr, Cu, Hg, Pb and Zn. The percentages of these elements in particles with diameters less than 63 μm (PM63) and less than 101 μm (PM101) were in the range of 7–15%, and 30–55%, respectively. Three main factors influencing element distributions have been identified: (a) industrial activities; (b) prior agricultural land use; and (c) other activities commonly found in urban areas, such as traffic, coal combustion, waste dumping, and building construction/renovation. The highest concentrations were found in industrial areas for As (20 mg kg−1), Cr (853 mg kg−1), Cu (1071 mg kg−1), Pb (3060 mg kg−1) and Zn (2112 mg kg−1), and in previous agricultural areas for Ag and Hg, indicating significant contributions from industrial activities and prior agricultural activities. 相似文献
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Environmental pulmonary health problems related to mineral dusts: Examples from central Anatolia, Turkey 总被引：1，自引：0，他引：1
M. Doğan 《Environmental Geology》2002,41(5):571-578
There are a number of benign disorders including pleural thickening (PT), calcified pleural plaques (CPP), and malignant diseases such as malignant pleural mesothelioma (MPM) in central Anatolia. Earlier studies suggested tremolite was the main cause, and there was no explanation why some of the population did not have malignant cases, and plaques were by far the most frequent manifestation of asbestos-induced injury. In this study, geological, mineralogical and environmental data were evaluated. While the prolonged continuous exposure to high or low doses of long (8-30 µm) and thin (less than 0.25 µm) mixed fibers such as chrysolite, and/or anthophyllite or tremolite, and also silica particles may be the cause of MPM in central Anatolia, two different reasons for the CPP and PT are suggested. The first one is short (less than 8 µm) and thin mixed-type mineral fibers. The second reason is low doses of long, but thick, splintery tremolite fibers. 相似文献
18.
Anthropogenic platinum,palladium and rhodium concentrations in road dusts from Hyderabad city,India 总被引：1，自引：0，他引：1
Ramavati Mathur V. Balaram M. Satyanarayanan S. S. Sawant S. L. Ramesh 《Environmental Earth Sciences》2011,62(5):1085-1098
This paper presents the first study of accessing the Pt, Pd and Rh levels in road dusts collected from Hyderabad city, India,
as these metals, emitted from automobile catalytic converters, are accumulating in the environment causing concern about human
health and ecological risks. Samples were analyzed by ICP-MS following preconcentration by NiS-fire assay and Te coprecipitation.
Pt (1.5–43 ng/g), Pd (1.2–58 ng/g) and Rh (0.2–14.2 ng/g) concentrations obtained were above upper crust values, but were
lower when compared with several other cities around the world. Dust samples from road junctions and traffic signals with
heavy and erratic traffic flow showed higher PGE levels than those from roads with low and free flow traffic suggesting that
traffic flow conditions greatly influenced emission of PGE from the catalyst. Significant correlation of Pt, Pd and Rh indicate
a common source for these metals. PGE were also positively correlated with Ce, Zr, Hf and Y. These positive inter-element
correlations identified traffic as the main source of PGE emission to the roadway environment. The results obtained indicate
to an appreciable increase in auto catalyst-derived PGE. In consideration of the adverse effects of PGE, monitoring their
level and transformation paths is of prime importance. 相似文献
19.
Multivariate analysis of heavy metal pollution in street dusts of Xianyang city, NW China 总被引：3，自引：2，他引：1
Urban street dust is one of important indicators of the status of urban environmental pollution. There are many studies in capital cities, but little attention has been paid to this kind of study in medium cities, especially in China. The dust samples were collected in the district of traffic crossroads in Xianyang city, Shaanxi Province. Pb, Cd, Cu, Ni, Zn, Cr and Mn concentrations were determined by using atomic absorption spectrometry. The results indicate that street dusts in Xianyang city have elevated metal concentrations as a whole in comparison with Shaanxi Province soil, except for Mn. The content of heavy metals was comparable to those in capital cities. Correlation coefficient analysis, principal component analysis and cluster analysis were used and three main sources were identified; Mn comes mainly from soil sources; Cu, Zn and Ni are mainly derived from industrial sources combined with traffic sources; Pb, Cr and Cd have traffic sources. Heavy metal enrichment factors were calculated, which can reflect human influence degree of street dusts. 相似文献