溶出伏安法测定痕量铅

本文提出在氯化吡啶溶液中以汞膜电极为工作电极,大量锡存在下阳极溶出伏安法测定铅。并对富集和溶出的实验条件,方法的精密度,回收率和共存元素的干扰进行了探讨。     

微分脉冲阳极溶出伏安法测定岩石和土壤中痕量铟

应用方波极谱,催化波测定矿石中微量铟已有报导,但仅限以测定0.Xppm以上样品中铟,而对岩石、土壤中测定0.0Xppm铟尚不多见。虽然用阳极溶出伏安法测定铟有一些文献报导,但却只能用于某些基体较为简单的样品如锌、铝及其合金水质中铟的测定。 本文应用微分脉冲阳极溶出技术,在1.65N.KBr—0.05N-HCl—0.02％NH_2OH.HCl介质中,应用悬汞电极富集2分钟后,Cd~(2+),In~(3+),Pb~(2+)的溶出峰分别为-0.64,-0.52,及-0.41伏(Vs Ag/AgCl电     

微分脉冲阳极溶出伏安法测定岩石和土壤中痕量铟

应用方波极谱,催化波测定矿石中微量铟已有报导,但仅限以测定0.Xppm以上样品中铟,而对岩石、土壤中测定0.0Xppm铟尚不多见。虽然用阳极溶出伏安法测定铟有一些文献报导,但却只能用于某些基体较为简单的样品如锌、铝及其合金水质中铟的测定。 本文应用微分脉冲阳极溶出技术,在1.65N.KBr—0.05N-HCl—0.02％NH_2OH.HCl介质中,应用悬汞电极富集2分钟后,Cd~(2+),In~(3+),pb~(2+)的溶出峰分别为-0.64,-0.52,及-0.41伏(V_s Ag/AgCl电     

非接触极化曲线法实验研究的一些结果

本文讨论了利用非接触极化曲线法进行物探异常源评价的可行性。阐明和比较了接触极化曲线法和非接触极化曲线法的异同,并给出了黄铜、石墨及天然硫化矿石标本分别在自来水中和在0.01M的CuSO₄溶掖中实验测得的（视）阴极、阳极反应电位。（视）阴极、阳极极化曲线的差异以及某些反应段的极限电流密度。在利用反应电位,极差优势进行极化标本的识别和用极限电流密度推算反应物浓度以及利用视反应电位反演求取真反应电位等方面作了一些尝试．得出了许多有意义的结论。     

微分电位溶出分析法测定痕量铅

铅是对人体有害的元素之一,近年来引起人们极大的关注.测定微量铅的报导较多,本文用氯乙酸—氯化钠作支持电解质,微分电位溶出分析法(DPSA)测定痕量铅,检出限为2.6ng/ml,5～100ng/ml的铅与溶出峰高具有良好的线性关系.加入十二烷基硫酸钠(SDS)和乳化剂—OP等表面活性剂,不仅提高分析灵敏度,而且也增加了汞膜的使用寿命.测定地质、人发及天然水样中痕量铅,结果令人满意.     

计时电位溶出法同时测定样品中铜和铋

探讨了以预镀汞膜破碳电极为工作电极,同时测定锑类金属及其氧化物和硫化物中铜、铋的计时电位溶出法的适宜条件;试验了酸介质和常见元素对测定的影响;选择了仪器的最佳工作条件。结果表明,在０．１ｍｏｌ／ＬＨＣ１－０．０１ｍｏｌ／Ｌ抗坏血酸底液中,相对饱和氯化钾甘汞电极,铜与铋的溶出峰电位分别为－０．２０Ｖ和－０．１０Ｖ,分辨效果较好。在测定条件下,铜和铋的线性范围分别为０～３００ｕｇ／Ｌ和０～８０ｕｇ／Ｌ     

阳极溶出伏安法测定痕量锑的研究

本文提出在HCl-乙醇体系中,以棒状汞膜电极为工作电极,阳极溶出伏安法测定痕量锑。并对测定方法的灵敏度,精密度,回收率及共存元素的干扰情况进行了探讨。在0.3molL~(-1)HCl-乙醇溶液中测定了天然水和碳素钢中痕量锑,回收误差不超过10％。本文提出非水介质(0.3molL~(-1)HCl-乙醇溶液)中,用国产SDP-1型半微分快速极谱仪,以棒状汞膜电极为工作电极,不必事先分离和富集锑。测定天然水,碳素钢中痕量锑(检测下限达0.05ppb),碳素钢中锑测定结果与标准数据基本一致。     

阳极溶出伏安法测定天然水、岩石矿物中痕量铊

天然水、岩石矿物中铊含量很低,已有的分光光度法,原子吸收法和中子活化法等测定痕量铊,有灵敏度低,分析手续繁琐,且仪器昂贵等弱点。阳极溶出伏安法测定铊灵敏度可达3.5×10~(-10)M。所以,近年来有人用阳极溶出伏安法测定痕量铊,但直接测定干扰严重,必须事先用离子交换,共沉     

氰化物分解阳极溶出伏安法野外分析金

本文介绍了用于野外分析金的氰化物分解阳极溶出伏安法。该法操作简单，节省时间，现场就可直接得到分析结果。     

固体汞电极溶出伏安法测定地下水示踪剂中的铜及实验应用

用易溶于水的金属盐类试剂作示踪剂,是岩溶地下水示踪试验中广泛采用的有效方法,通过野外现场测定人工示踪剂中的金属离子可以揭示岩溶地下水的运动特征.传统极谱法所用的液态汞操作不便,且容易造成环境污染.本文制作了固体汞电极,采用溶出伏安法测定地下水示踪剂中的铜,在地下水样品中加入醋酸一醋酸钠缓冲溶液,氯化钾溶液作为支持电解质,采用固体汞电极扫描,记录溶出曲线.实验了氯化钾溶液、醋酸-醋酸钠缓冲溶液用量对100 ng/mL铜标准工作溶液峰电流的影响,在选定最佳实验条件下,铜浓度在0 ～ 1000 ng/mL范围内与峰电流呈现良好的线性关系,相关系数大于0.999,方法检出限为0.58 ng/mL,加标回收率为96.4％ ～ 101.7％.地下水中可能存在的一些离子对测定不产生干扰.该方法应用于地下水示踪试验,铜的测定结果与极谱法基本吻合,且简单快速,适合野外现场测定,同时避免了极谱法液态汞的污染问题.     

适用于壤气汞量测量的廉价捕汞管

壤气汞量测量在我国的应用日趋广泛,迄今使用的原子吸收测汞仪已达数百台,由于金丝捕汞管价格高昂,严重影响了这一方法在生产中的大量应用。本文提出了一种基于以活性炭物理吸附取代常规的汞齐化学吸附的捕汞管,其吸附和脱吸附汞的性能有所提高,可以反复使用,成本大为下降,从而使每一个拥有单波长原子吸附测汞仪的单位均有能力配备足够的捕汞管,开展生产性壤气测汞工作。本文讨论了活性炭搏汞管吸附与脱吸附汞的最佳工作条件及工作方法,干扰的构成原因及排除措施,并且对壤气组份中理论上存在的干扰气体问题进行了试验与讨论。文中给出了二种捕汞管在几个不同矿床上的对比试验结果,还在浙江某金矿远景区进行了应用试验,结果表明活性炭捕汞管与金丝捕示管的地质效果相同。     

The mercury problem in the Amazon due to gold extraction

The environmental impacts caused by the use of mercury (Hg), as a gold (Au) amalgam, in gold extraction in three geographical areas located in the Brazilian wetlands (Poconé) and the Amazon (Alta Floresta and Itaituba), are reviewed and solutions proposed.     

Gold in the volcanogenic mercury-rich sulfide deposit Långsele,Skellefte ore district,northern Sweden

The mineralogy of gold from a volcanogenic sulfide deposit in northern Sweden (Långsele) was studied. The enrichment of gold and silver in massive ore occurs associated with an intrusive metadolerite vein which can be traced across the ore. The emplacement of this vein mobilized the precious metals together with galena and Pb-Sb sulfosalts into fractures and low pressure zones. A high mercury content at L»ngsele (average 250 ppm) has influenced the gold mineralogy. Thus, gold occurs as Au-Ag amalgam, native gold and rarely as aurostibite (AuSb₂). The results of microprobe analyses of amalgam cluster around Au_0.45Ag_0.45Hg_0.10. The composition of ternary amalgam is discussed in connection with the synthetic Au-Ag-Hg system. Furthermore, native gold was found myrmekitically integrown with stibnite which has been interpreted as a breakdown product of aurostibite at low temperature.     

贵州万山汞矿区稻田土壤汞的分布及污染特征

受历史汞矿开采活动影响,万山汞矿区稻田遭受了严重的汞污染.为了查明万山汞矿区稻田土壤的汞污染现状以及评估其环境质量改善情况,系统采集了受汞矿区影响的五条主干河流沿岸稻田土壤进行汞含量分析,评价总汞和甲基汞污染程度及其生态风险,并与2008 年以来该区域稻田土壤汞数据进行对比.结果表明,研究区稻田土壤的总汞含量为0.21...     

Environmental geochemistry of mercury in the area of emissions of the Karabashmed copper smelter

Mercury emissions during production of blister copper at the smelter Karabashmed are roughly estimated. The high mercury content in the atmospheric dust, soils, lake sediments of the Karabash geotechnogenic system shows that emissions of the plant are the main source of environmental contamination. The mercury content in soils of residential territory ranges within 0.2–11.4 mg/kg, reaching 15 mg/kg in soils of the impact zone. The maximum mercury content in the bottom sediments of Lake Serebry is 32 mg/kg. The high degree of contamination by other elements of emissions (Cu, Pb, Zn, As, Cd) is also demonstrated. Obtained results justify the need for the instrumental control of mercury in emissions.     

淮南采煤沉陷区土壤中汞的时空分布特征

以淮南采煤沉陷区土壤为研究对象,测试分析了样品中汞的含量,结合土壤pH值、有机质含量特征,探讨了采煤沉陷区土壤中汞的时空分布特征。结果表明:与未沉陷区土壤相比,沉陷区土壤有机质破坏严重,最高下降了46%;采煤沉陷区土壤中汞的含量为0.013~0.050 mg/kg,平均值为0.027 mg/kg,69.7%的采样点超过了淮南市土壤背景值;沉陷8 a后土壤汞含量最高,为0.033 mg/kg,是未沉陷土壤汞含量的1.74倍,且随着沉陷时间的增加,土壤中汞存在富集趋势;水稻土壤汞富集能力最高,高于玉米和大豆土壤;在垂直剖面上,汞含量由表层向下依次降低;且汞与pH值表现出显著负相关,有机质与汞显著正相关。      

The role of geomorphic processes in the transport and fate of mercury in the Carson River basin, west-central Nevada

 The historic processing of precious metal ores mined from the Comstock Lode of west-central Nevada resulted in the release of substantial, but unquantified amounts of mercury-contaminated mill tailings to the Carson River basin. Geomorphic and stratigraphic studies indicate that the introduction of these waste materials led to a period of valley-floor aggradation that was accompanied by lateral channel instability. The combined result of these geomorphic responses was the storage of large volumes of mercury-enriched sediment within a complexly structured alluvial sequence located along the Carson River valley. Much of the contaminated sediment is associated with filled paleochannels produced by the cutoff and abandonment of meander loops, and their subsequent infilling with contaminated particles. Geochemically, these deposits are characterized by variations in mercury levels that exceed three orders of magnitude. Continued lateral instability, coupled with an episode of channel-bed incision, followed the decline of Comstock mining, and has reexposed contaminated debris within the banks of the river. Erosion of bank sediments reintroduces mercury-enriched particles to the modern channel bed. It is suggested on the basis of geochemical and sedimentological data that during the bank erosion process, much of the mercury associated with fine (<63 μ) valley-fill deposits are carried downstream without being incorporated to any appreciable extent within the channel-bed sediments. In contrast, mercury associated with larger and denser particles, particularly mercury-gold-silver amalgam grains, are accumulated in the channel-bed sediments as the river traverses polluted reaches of the Carson River valley. Concentration patterns developed along the modern channel indicate that the valley fill is the primary source of mercury to the river today. Thus, these data imply that efforts to reduce the influx of mercury to the aquatic environment should examine methods for reducing bank erosion rates. Received: 13 December 1996 · Accepted: 15 April 1997     

Parameters influencing the variation in mercury emissions from an Alberta power plant burning high inertinite coal over thirty-eight weeks period

Feed coals and fly ashes from a coal-fired power station burning Alberta subbituminous coal were examined for a period of thirty-eight weeks to determine the variation in emitted mercury. Feed coal samples were analyzed for proximate, calorific value and Hg content, while fly ash samples were examined for C and Hg contents. The maceral content of the feed coal was also determined. The emitted mercury was calculated and compared to mercury emitted from the stack according to a mass-balance calculation from a previous study for the same station.Mercury contents ranged from 0.029 to 0.066 mg/kg for feed coal, and from 0.069 to 0.112 mg/kg for fly ash. The carbon/char in fly ash was separated into reactive (vitrinitic/bimacerate) and less reactive (inertinitic) chars using ZnBr₂ at specific gravities of 1.7, 2.0, and 2.25 to 2.4. The result shows that there is a positive correlation between the carbon and mercury content of the fly ash. The reactive char particles in the fly ash may be responsible for the capture mercury in fly ash. The percentage of estimated captured mercury by fly ash increases with increasing carbon content (%) in fly ash. The percentage of emitted mercury for the period of 38 weeks is estimated to be within the range of 49% to 76% of the total input of mercury.     

应用于水文与工程地质的化探新方法土壤吸附汞地球化学测量

介绍了化探土壤吸附汞地球化学测量方法的基本原理,指出土壤中汞异常具有多种来源,单一测汞方法不能区别其来源。测汞方法最重要的作用最准确指出汞气的迁移通道－基岩的断裂破碎带。因此该方法更适用于水文与工程地质勘查,特别是地下水勘查。