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1.
样品经硝酸-氢氟酸混合酸溶解后,用标准加入-原子吸收光谱法测定钢渣中的铁。实验探讨了钢渣的均匀性等干扰因素对结果的影响,并提出基体高、浓度高的样品稀释倍数过高误差越大,建议采用如旋转燃烧头、选择次灵敏线等降低仪器灵敏度的方法或采用标准加入法。并将标准加入法与X射线荧光光谱、电感耦合等离子体发射光谱、原子吸收光谱直接测定法进行比较,铁的实验结果分别为51.6%、54.2%、46.2%、16.6%,相对标准偏差分别为2.8%、5.3%、2.0%、2.3%。标准加入-原子吸收光谱法用于测定基体高、浓度高的样品是准确可靠的。方法可用于环境类实验室用水剂标准溶液进行钢渣类样品中元素的分析。 相似文献
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标准加入-原子吸收光谱法测定钢渣中的铁 总被引：1，自引：1，他引：0
样品经硝酸-氢氟酸混合酸溶解后,用标准加入-原子吸收光谱法测定钢渣中的铁.实验探讨了钢渣的均匀性等干扰因素对结果的影响,并提出基体高、浓度高的样品稀释倍数过高误差越大,建议采用如旋转燃烧头、选择次灵敏线等降低仪器灵敏度的方法或采用标准加入法.并将标准加入法与X射线荧光光谱、电感耦合等离子体发射光谱、原子吸收光谱直接测定法进行比较,铁的实验结果分别为51.6%、54.2%、46.2%、16.6%,相对标准偏差分别为2.8%、5.3%、2.0%、2.3%.标准加入-原子吸收光谱法用于测定基体高、浓度高的样品是准确可靠的.方法可用于环境类实验室用水剂标准溶液进行钢渣类样品中元素的分析. 相似文献
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Ricardo Cesar Silvia Egler Helena Polivanov Zuleica Castilhos Ana Paula Rodrigues 《Environmental Earth Sciences》2011,64(1):211-222
Mercury, zinc and copper contamination was evaluated in soils and fluvial sediments from an abandoned gold mining site at
Descoberto Municipality (southern Minas Gerais State, Brazil). Metals bioavailability and potential mobility were studied
through physical, chemical and mineralogical characterization, geoaccumulation indexes calculations, mercury speciation and
determination of potentially bioavailable contents of zinc and copper. Values of pH were in the neutral range, while organic
matter concentrations were very low. Mineralogical characterization, in the total samples, indicated the presence of quartz,
kaolinite and gibbsite for all samples. Total mercury, zinc and cooper concentrations were higher than the limits recommended
by Brazilian documents. Geoaccumulations indexes revealed that most of the sediment samples were low to moderately polluted
by zinc and copper, while just one sample was very strongly polluted by mercury. Mercury speciation revealed the predominance
of the elementary form for all samples, and low concentrations for exchangeable, strongly bound and residual fractions. Zinc
and copper behavior was strongly controlled by iron and aluminum concentrations, while their bioavailable contents were very
low in comparison with the total concentrations. 相似文献
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植物样品中无机元素分析的样品前处理方法和测定技术 总被引：11，自引：5，他引：6
植物样品中无机元素的分析测定在环境地球化学和生物地球化学的研究中起着重要作用。植物样品中元素含量一般较低,须选用科学合理的前处理技术和灵敏度高、精密度好、检出限低的测定方法。本文针对植物样品前处理方法和无机元素分析测定技术的研究进展、优势与不足进行评述。前处理方法主要根据样品和待测元素的性质进行选择:干法灰化所用试剂少、空白值低,但组织致密型的样品不易灰化完全、高温下易造成元素挥发损失;湿法消解样品消解较为完全,但试剂消耗大、空白值高、操作繁琐;微波消解可以防止部分易挥发元素损失,用酸量少、消解速度快,但称样量相对较小,不适于需要大称样量的样品分析。几乎所有针对元素分析的仪器分析技术都可以用于植物样品分析,主要根据仪器适用的元素、必要的干扰校正以及基体改进等方面进行选择:电感耦合等离子体质谱法可同时测定植物样品中40种以上的元素,高分辨质谱的检出限可达fg/mL;电感耦合等离子体发射光谱法适用于某些植物样品中含量较高的P、K、Na等元素的测定;原子吸收光谱法可分析元素达70余种,是普及程度最高的仪器分析技术之一;原子荧光光谱法与氢化物发生技术的联用,在元素含量较低的植物样品分析中技术优势更加明显;新兴的激光诱导击穿光谱技术已被应用于植物样品分析,无需复杂的样品前处理,操作简单快速,可实现原位、在线、实时、多元素同时检测;其他选择性强、灵敏度高的分析技术,满足了一些特定元素不能用常规分析技术测定的需求。当前主流分析技术的样品前处理方法都存在着缺陷,固体进样技术将成为植物样品分析领域的发展方向之一。 相似文献
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混合酸敞开或高压密闭溶样-ICPMS测定地质样品中稀土元素 总被引：9，自引：9，他引：0
测定地质样品中的稀土元素时,用碱熔法处理样品过程繁琐,混合酸敞开酸溶法的酸种类多,用量较大,而微波消解法批次处理样品少,效率不高。本文比较了7种混合酸敞开酸溶体系、硝酸-氢氟酸高压密闭体系对样品溶样的效果,采用电感耦合等离子体质谱测定15个稀土元素的含量,建立了一套样品前处理体系简单、酸用量少、相对快捷的测定地质样品中稀土元素的方法。通过对59件国家标准物质的测试分析,结果表明硫酸-氢氟酸敞开酸溶和硝酸-氢氟酸高压密闭溶样两套体系的方法检出限、精密度、准确度均能达到地质行业相关标准测试要求。硫酸-氢氟酸敞开酸溶体系对于样品中钡含量较高,或样品量较少时适用;硝酸-氢氟酸高压密闭溶样体系的检出限更低,适用于大批量样品的分析测试。两套体系均不需要进行数学干扰校正,且酸用量少（最多6 mL）,分析效率高（平均每日分析测试300件）,有较大的推广应用价值。 相似文献
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The sequential extraction procedure was proposed and used to study of mercury speciation in real samples of soil. Samples
of soil profiles together with bedrock and coal were taken from sampling spots in the vicinity of surficial coal beds in an
area with natural coal outcrops. The proposed sequential extraction procedure involves the following fractionation: organic
mercury compounds, extractable mercury in an acidic medium, mercury bound to humic substances, elemental Hg and mercury bound
to complexes, HgS and residual mercury. The significant distribution of mercury between the two portions—mercury bound to
humic substance and HgS was determined in the majority of samples. The mercury bound to humic substances created a significant
contribution, especially to the top layer of soil. On the other hand, HgS was the dominant form in the samples from lower
layers of the soil profile. The mercury content in the samples did not show a distinct mobility. The influence of soil parameters
on the mercury distribution in the studied samples was investigated and discussed. 相似文献
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地电化学（泡塑）样品中金与锑的预处理 总被引：3，自引：1，他引：3
通过模拟实验获得附载金、锑的泡塑样品，并对其进行了硫脲解脱法、灰化法、硝酸加氧化剂消解法的比较实验，确定采用硫脲解脱法是地电化学(泡塑)样品金、锑的最佳解脱方法，通过正交实验及其结果分析确定了最佳实验条件。利用硫脲解脱一原子吸收光谱法对某隐伏金锑矿床82件地电化学(泡塑)样品进行了测试，分析结果显示出有明显的金、锑异常，指示了重要的勘探靶区。 相似文献
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Leonard Boszke Artur Kowalski Witold Szczuciński Grzegorz Rachlewicz Stanisław Lorenc Jerzy Siepak 《Environmental Geology》2006,51(4):527-536
The 26 December 2004 tsunami covered significant portion of a coastal zone with a blanket of potentially contaminated sediments. In this report are presented results on mercury concentrations in sediments deposited by the tsunami in a coastal zone of Thailand. Since the total mercury concentrations are insufficient to assess mercury mobility and bioavailability in sediment, its fractionation was applied. Sediments were sampled within 50 days after the event and analyzed by sequential extraction method. The procedure of sequential extraction involved five subsequent stages performed with solutions of chloroform, deionized water, 0.5 M HCl, 0.2 M NaOH, and aqua regia. The mean concentration of total mercury in sediments was 119 ± 50 ng g−1 dry mass (range 66–230). The fractionation revealed that mercury is mainly bound to the least bioavailable sulphides 75 ± 6% (range 62–86), organomercury compounds 14 ± 7% (range 4–26), and humic matter 9 ± 7% (range 1–27). The lowest contributions bring fractions of water-soluble mercury 0.8 ± 1.0% (range 0.1–3.6) and acid soluble mercury 0.9 ± 0.5% (range 0.2–2.1). Although, the total mercury content is similar in a reference sample and in the tsunami sediments, the highly toxic organomercury fraction contribution is higher in the latter. The results were compared with chemical and sedimentological properties of the sediments but no significant correlations were obtained between them. 相似文献
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二十年来,国内外相继建立了多种金属（铁铜锌镁钙锂钼硒汞铬镉矾钡钛等）同位素的分析方法。金属同位素分析中的样品处理包括两个过程：样品的消解和样品中待测元素的分离纯化。为了获得真实、准确的金属同位素数据,样品处理过程必须遵守两个基本原则：①不引入待测元素以及可能会对待测元素同位素分析产生干扰的元素;②待测元素不发生损失。金属同位素分析常用的样品消解方法是酸溶法（包括高压闷罐法和微波消解法）。待测元素的分离纯化主要使用离子交换分离法。相同的树脂可以用于不同元素的化学分离,同一种元素也可以使用不同的树脂进行化学分离。不同类型样品的基质差异较大,需要不同的流程对待测元素进行分离。研究人员可以通过改变前人的分离流程,包括改变树脂的用量、变换淋洗液或用量、增加分离步骤等方法来满足不同样品的分离要求。本文提出了金属同位素样品处理中需要注意的一些细节：①如果消解样品时使用了高氯酸,必须将高氯酸在高温下彻底去除,因为残余的高氯酸具有强氧化性会使后续化学分离中使用的离子交换树脂失效,影响分离效果;②同一体积的树脂放入不同内径的交换柱中,树脂柱越细越长,淋洗液流速越慢、洗脱时间越长,并且待测元素洗脱出来越滞后;③离子交换过程中,每次加入的试剂体积越小,淋洗出来的元素越集中,分离效果越好。 相似文献
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灰化法和微波消解法作为地电化学泡塑样品的预处理方法适用于多数元素,但二者都存在局限性,如灰化法的高温加热过程会造成As、Hg等元素的损失影响测定结果,微波消解法则因用样量小(0.1 g),存在样品代表性和检出限方面的问题。湿法消解是一种传统的样品预处理方法,具有消解完全、元素损失量低、样品代表性好等优点,可以有效解决以上两种方法的不足。但因为加入高氯酸消解泡塑(有机物)样品过程中易爆炸和酸空白等问题,一直没有在泡塑样品的预处理中得到推广。本文选取内蒙古洛恪顿热液型铅锌多金属矿床一条地电化学勘查剖面,用20 m L硝酸+5 m L高氯酸和5 m L王水对泡塑样品(约0.5 g)进行预处理,氢化物发生原子荧光光谱法和高分辨电感耦合等离子体质谱法测定元素含量。结果表明:大多数元素的空白含量都比较低,地球化学剖面图上有良好的异常显示;湿法消解处理泡塑样品是可行的,分析泡塑样品主要使用这种预处理方法。 相似文献
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森林沼泽区富含有机质样品中金的存在形式及对分析的影响 总被引：1，自引：4，他引：1
为探讨中国东北森林沼泽地区富含有机质样品中金偏低的原因,采用了王水溶矿法和四酸溶矿法的AAS分析来测定样品中的Au。用四酸溶矿法驱除硅胶,明显地提高金的测定值,特别是对含量大于10-9的样品,2种分析方法的差别更大。通过以上研究发现,在森林沼泽区的富含有机质样品中,金除以有机质结合形式存在于介质中,还可能以胶体或纳米形式存在于样品中,并被SiO2胶体所包裹,在高浓度有机酸的保护下,金能在水溶液中呈活动形式做长距离迁移;但用王水溶矿法不能测定出这种被SiO2胶体包裹形式的金。 相似文献
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Gold has been determined in 26 geochemical reference samples with graphite furnace AAS after digesting the samples with aqua regia and hydrofluoric acid and extracting gold by methyl isobutyl ketone (MIBK). This method yields clearly higher values than those by the partial attack using aqua regia digestion. 相似文献
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This review describes developments major and in trace element determination using atomic absorption spectroscopy (AAS), inductively coupled plasma-atomic emission spectrometry (ICP-AES), instrumental neutron activation analysis (INAA), and X-ray fluorescence (XRF) spectrometry that were reported in 2008 and 2009. Publication levels were comparable to those of previous years, except for XRF which showed an increase in the number of articles published in the past 2 years. In terms of number of publications and impact, the most active field was AAS, while INAA was the least active. As expected for well-established and mature methods, novel developments for all four analytical techniques were relatively sparse. For AAS, the most notable publications concerned developments in sample introduction, particularly focussing on solid samples, increasing analyte sensitivity, and higher sample throughput. For ICP-AES, publication of developments in sample introduction, remediation of matrix effects and calibration continues. Compared with past years, there was a clear focus on sample preconcentration methods, but very few publications reporting new hyphenated speciation methods. For INAA, there were several publications exploring the accuracy and robustness of the method, as well as the requirements for INAA to meet criteria for a primary method of measurement. Two other related techniques, delayed neutron activation analysis, and prompt gamma activation analysis, were also described. Hyphenated XRF techniques showed interesting developments in enabling XRF and XRD analysis on the same spot, and further work characterising and calibrating three-dimensional micro-XRF shows promising results for investigating sample heterogeneity. 相似文献
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Determination of major and trace elements in sphalerite using laser ablation double focusing sector field ICP-MS 总被引：1，自引：0，他引：1
The analytical performance of laser ablation (LA) for the determination of Co, Fe, Cd, Ag, Mn, Cu and S in sphalerite was evaluated using double focusing sector field inductively coupled plasma mass spectrometry (ICP-SFMS). Samples were collected from Zinkgruvan, situated in the south central Sweden. The use of Zn for internal standardisation, together with correction for FeS impurities in sphalerite, allows straightforward quantification without using external methods for the determination of the actual Zn content. LA–ICP-SFMS results were compared with data obtained by conventional pneumatic nebulisation introduction of sample solutions following acid digestion. Good agreement between the two methods was obtained for homogeneously distributed elements. For the majority of the elements under consideration, LA–ICP-SFMS precision was better than 10% RSD. 相似文献
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An Evaluation of Methods for the Chemical Decomposition of Geological Materials for Trace Element Determination using ICP-MS 总被引：3，自引：0，他引：3
Zongshou Yu Philip Robinson Peter McGoldrick 《Geostandards and Geoanalytical Research》2001,25(2-3):199-217
Complete dissolution is essential to obtain accurate analytical results using ICP-MS. In this study, decomposition techniques (i.e. acid digestions using Savillex Teflon vials, a high pressure digestion system and microwave oven, a combined lithium tetraborate fusion - HF/HNO3 acid decomposition and sodium peroxide sinter) for the total dissolution of different types of geological reference materials have been investigated. Savillex Teflon vial HF/HNO3 digestion is effective for basaltic samples. The high pressure HF/HClO4 digestion (PicoTrace TC-805 digestion system, Bovenden, Germany) allows dissolution of basalts and ironstones. Granites and magnetite-rich samples can be dissolved using a high pressure HF/H2 SO4 method. Geological samples cannot be effectively attacked by microwave acid digestion. A combined lithium tetraborate fusion - HF/HNO3 acid digestion method allows complete dissolution of many different types of geological materials; however, this method precludes the determination of volatile elements due to the high fusion temperature (1000 °C). A sodium peroxide sinter method at 480 °C has the potential for the rapid determination of Y, Sc and REE in different types of geological materials. However, the lack of ultra-pure reagents precludes the use of lithium tetraborate fusion and sodium peroxide sinter methods for the measurement of geological samples with low trace element abundances. 相似文献
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灰化法与微波消解法处理地电化学泡塑样品的分析效果对比研究 总被引：1，自引：1，他引：0
当前普遍使用灰化法对地电化学泡塑样品进行预处理,但可能存在高温下某些元素(如Hg、As)挥发损失的缺点。本文选择了内蒙古洛恪顿热液型铅锌多金属矿床一条地电化学勘查剖面,开展灰化法及微波消解法处理地电化学泡塑样品的勘查效果对比研究,采用原子荧光光谱和高分辨电感耦合等离子体质谱测定其中的主要元素。结果表明:①对于Zn、Cu、Fe、La等十余种元素,两种处理方法取得的异常模式基本一致,可根据实际工作需求任选一种方法进行样品预处理;②对于Au、Pb等元素,微波消解法因为取样量小,可能存在较严重的样品均匀性、代表性及分析检出限等问题,应采用灰化法;③对于Hg,灰化法存在显著的元素损失,更适合采用微波消解法;④对于As,两种方法均存在较大问题,建议参考植物样品尝试使用硝酸及高氯酸直接溶解等方法进行预处理。 相似文献