原子吸收光谱法测定地质样品中金时样品分解方法的改进

本文叙述了用原子吸收光谱法（ＡＡＳ）测定地质样品中金的方法，该法包括顺序使用ＨＢｒ－Ｂｒ２和王水〔ＨＣｌ－ＨＮＯ３（３＋１）〕消化的改进程序。焙烧样品首先用ＨＢｒ－Ｂｒ２混合物处理样品。金从水相进入有机相，干渣再用王水浸取，金在Ｓｎ（Ⅱ）Ｃｌ２溶液中同亚碲酸钾共沉淀。沉淀萃入甲苯，金制成王水溶液，最后喷雾进入空气－乙炔火焰。该方法地各种基体的不同材料中金的测定。     

铑作基体改进剂石墨炉原子吸收法测定海洋生物样品中的痕量砷

采用铑作基体改进剂,消除样品中共存磷酸盐基体的干扰,实现了用塞曼石墨炉原子吸收法测定贻贝、虾粉、牡蛎等海洋生物样品中痕量砷。方法的ＬＤ为２５ｐｇ（１０μＬ进样）,线性范围在０～１２５μｇ／ＬＡｓ。标准加入法测定砷的回收率为８５％～１０２％,１０－６水平Ａｓ的测定ＲＳＤ（ｎ＝６）小于７％,分析结果与标准样品的标准值和氢化物原子吸收法测定结果相符。     

微波消化在磷矿石样品制备中的应用

以微波ＨＮＯ＿３消化分解磷矿石试样，用ＩＣＰ－ＡＥＳ进行多元素同时测定。该方法经磷矿石标准样品验证后，用于云南省九个地区磷矿中Ｃａ、Ｐ、Ｆｅ、Ａｌ、Ｍｇ和Ｋ六种元素的分析，结果与经典酸分解方法制备样品的分析结果相符；同一样品平行测定９次，其各元素的相对标准偏差（ＲＳＤ）在１．５８％～４．４１％。     

沉淀分离—火焰原子吸收光谱法连续测定锌精矿中杂质元素

利用Ｚｎ（ＯＨ）２的两性沉淀富集待测杂质元素，分离高含量Ｚｎ以排除干扰，用火焰原子吸收法测定其中的杂质元素含量。实验结果表明：分离后残留的Ｚｎ对Ｆｅ、Ｃｄ、Ｎｉ、Ｍｎ、Ａｇ的测定无干扰；各元素之间互不干扰。加标回收率为９３％￣１０６％，对菱锌矿中几种杂质元素进行测定，结果与ＩＣＰ－ＡＥＳ法相符，各元素测定的相对标准偏差（ｎ＝１２）为４．１％￣８．８％。     

沉淀分离－火焰原子吸收光谱法连续测定锌精矿中杂质元素

利用Ｚｎ（ＯＨ）＿２的两性沉淀富集待测杂质元素，分离高含量Ｚｎ以排除干扰，用火焰原子吸收法测定其中的杂质元素含量。实验结果表明：分离后残留的Ｚｎ对Ｆｅ、Ｃｄ、Ｎｉ、Ｍｎ、Ａｇ的测定无干扰；各元素之间互不干扰。加标回收率为９３％～１０６％，对菱锌矿中几种杂质元素进行测定，结果与ＩＣＰ－ＡＥＳ法相符，各元素测定的相对标准偏差（ｎ＝１２）为４．１％～８．８％。     

泛滥平原沉积物的超低密度采样代表性研究(一)

运用１个样／１ｋｍ２、１个组合样／４ｋｍ２，１个样／（１００～１０００）ｋｍ２、１个样／（１０００～１００００）ｋｍ２的采样密度系统研究了泛滥平原沉积物的超低密度采样代表性。通过对Ｓｂ、Ａｓ、Ａｇ、Ｐｂ、Ｓｎ、Ｎａ２Ｏ元素的地球化学分布模式，Ｗ的地球化学特征在不同采样密度间的信息传递，证明了用１个样／（１０００～１００００）ｋｍ２的采样密度，采集的泛滥平原沉积物具有代表性     

等离子体发射光谱法测定大气颗粒物中的无机元素

建立了用等离子体发射光谱（ＩＣＰ－ＡＥＳ）测定大气颗粒物中无机元素的分析方法,包括样品消解体系的选择,仪器的操作条件及采样滤膜的选择,产对自行采样分析测得的无机元素数据作了初步的讨论。实验结果表明：采用ＨＮＯ３－ＨＣｌＯ４消解体系,操作方便,样品消解较完全;选用石英滤膜查减低空白值,保证测定质量以及同时在一张滤膜上测定大气颗粒物中的有机碳、元素碳及无机元素;内标法可有效降低由于仪器漂移等因素对测定     

天然水中超痕量金的测定

用石墨炉原子吸收光谱（ＧＦＡＡＳ）或感应耦合等离子体质谱（ＩＣＰ－ＭＳ）评估了几种预富集天然水中溶解金的方法。在ＧＦＡＳＳ之前用阴离子交换法和在ＩＣＰ－ＭＳ之前用溶剂萃取法，两种方法都证实有相似的回收率，低的检出限（２Ｌ样品检出限分别是０．４ｎｇ．Ｌ＾－１和０．２ｎｇ．Ｌ＾－１）和好重现性。还用仪器中子活化分析（ＩＮＡＡ）进行了颗粒金的平行分析，以提供一个对转（迁）移金的完整的评价，检出在０．４～     

黄土和沉积岩中分离方解石和白云石的方法实验

采用不同浓度的ＨＣｌ、ＨＡｃ、ＮＨ４Ａｃ及ＮＨ４Ａｃ－ＨＡｃ缓冲深液对典型黄土剖面的黄土样品进行了系统的浸取实验,结果表明,稀ＨＡｃ是分离方解石与白云石的最佳深剂,在浸取实验中对１４种不同元素含量进行测试,多数元素的含量有变化,用稀ＨＡｃ溶液浸取所得的浸取注中＾８７Ｓｒ／＾８６Ｓｒ的测定结果与使用稀ＨＣｌ浸取的浸取液中＾８７Ｓｒ／＾８６Ｓｒ测定值有一定的差别,方法可满足在古气候研究中对不同成因碳酸盐利用的要求。     

黄沙坪铅锌矿床银与金金属元素组合特征

本文分析了不同矿石中Ａｇ与Ｐｂ、Ｚｎ、Ｃｕ、Ｓ等元素的相关性，并根据银含量变化规律，银矿物组合特征，划分Ｐｂ（Ｚｎ）－Ａｇ－Ｓｎ－Ｓｂ和Ｃｕ（Ｍｏ）－Ａｇ－Ｔｅ－Ｂｉ两个不贩银的矿化组合。     

植物样品中无机元素分析的样品前处理方法和测定技术

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。     

四种前处理方法对电感耦合等离子体质谱测定植物样品中27种微量元素的影响

采用HNO₃-HClO₄-HF常压消解、HNO₃-H₂O₂-HF高压密闭消解、HNO₃-H₂O₂微波消解,干法灰化后残渣用HNO₃-HF-HClO₄溶解等四种方法对植物样品进行前处理,使用电感耦合等离子体质谱(ICP-MS)对植物样品中的27种元素进行定量分析,探讨了不同前处理方法对ICP-MS测定植物样品中微量元素的影响。分析结果表明: HNO₃-HClO₄-HF常压消解使用大量试剂,污染环境,造成空白值高;在常压体系中HClO₄的加入能提高样品的消解效率,但赶酸不完全,会造成复合离子对钒和砷的干扰;干法灰化过程中某些元素(硼、汞等)会损失;常压消解和高压密闭消解中加入HF能有效地提高铍、稀土、钇、钛、锑、铀等元素的回收率,但在蒸干赶HF的过程中,会造成硼和汞的损失,并且钢套的生锈会造成铬、镍空白值高。尽管没有一种方法能适用于所有元素的分析,但相比较而言,HNO₃-H₂O₂微波消解体系操作简单,大部分元素(除铍、钛、锑、铋、稀土)能得到满意的结果,精密度(RSD)均小于10%(n=10),相对误差(RE)为-4.6%~13.6%。     

湿法消解预处理地电化学泡塑样品有效性研究

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。     

地表水和地下水水质分析前处理问题探讨

运用石墨炉原子吸收光谱法、电感耦合等离子体发射光谱法和电感耦合等离子体质谱法对0.45μm滤膜过滤前后的地表水和地下水溶液中的微量元素铁、锰、锌、铅、铜、镍、铬和镉进行了定量分析。结果发现,由于微生物的存在及其对水中微量元素的吸附作用,经过滤的酸化水直接测定结果比其经消解处理的测定结果偏低。建议在水质分析前,对样品进行低温消解前处理。     

An Investigation of Digestion Methods for Trace Elements in Bauxite and Their Determination in Ten Bauxite Reference Materials Using Inductively Coupled Plasma‐Mass Spectrometry

Trace elements from samples of bauxite deposits can provide useful information relevant to the exploration of the ore‐forming process. Sample digestion is a fundamental and critical stage in the process of geochemical analysis, which enables the acquisition of accurate trace element data by ICP‐MS. However, the conventional bomb digestion method with HF/HNO₃ results in a significant loss of rare earth elements (REEs) due to the formation of insoluble AlF₃ precipitates during the digestion of bauxite samples. In this study, the digestion capability of the following methods was investigated: (a) ‘Mg‐addition’ bomb digestion, (b) NH₄HF₂ open vessel digestion and (c) NH₄F open vessel digestion. ‘Mg‐addition’ bomb digestion can effectively suppress the formation of AlF₃ and simultaneously ensure the complete decomposition of resistant minerals in bauxite samples. The addition of MgO to the bauxite samples resulted in (Mg + Ca)/Al ratios ≥ 1. However, adding a large amount of MgO leads to significant blank contamination for some transition elements (V, Cr, Ni and Zn). The NH₄HF₂ or NH₄F open vessel digestion methods can also completely digest resistant minerals in bauxite samples in a short period of time (5 hr). Unlike conventional bomb digestion with HF/HNO₃, the white precipitates and the semi‐transparent gels present in the NH₄HF₂ and NH₄F digestion methods could be efficiently dissolved by evaporation with HClO₄. Based on these three optimised digestion methods, thirty‐seven trace elements including REEs in ten bauxite reference materials (RMs) were determined by ICP‐MS. The data obtained showed excellent inter‐method reproducibility (agreement within 5% for REEs). The relative standard deviation (% RSD) for most elements was < 6%. The concentrations of trace elements in the ten bauxite RMs showed agreement with the limited certified (Li, V, Cr, Cu, Zn, Ga, Sr, Zr and Pb) and information values (Co, Ba, Ce and Hf) available. New trace element data for the ten RMs are provided, some of which for the first time.     

New REE and Trace Element Data on Two Kimberlitic Reference Materials by ICP-MS

Data on thirty-four minor and trace elements including all rare earth elements (REE) are reported for two kimberlitic international reference materials (SARM-39, MINTEK, RSA and MY-4, IGEM, Russia) by inductively coupled plasma-mass spectrometry (ICP-MS), some of them for the first time. Four digestion techniques (open acid, closed vessel acid, microwave and lithium metaborate fusion digestion) were used for the decomposition of samples for analysis by ICP-MS. Three other reference materials (USGS BHVO-1, CRPG BR-1 and ANRT UB-N) were analysed simultaneously using the same analytical methodology to assess the precision and accuracy of the determinations. The data obtained in this study compare well with working values wherever such values are available for comparison. Though open acid digestion was found to be very rapid, effective and convenient for the determination of several trace elements in kimberlitic samples, recoveries for heavy rare earth elements (HREE) were lower than the respective recoveries obtained by the other decomposition techniques used. The precision obtained was better than ± 6% RSD in the majority of cases with comparable accuracy. Chondrite-normalised plots of each RM for all the digestion techniques were smooth. The new data reported on the two kimberlitic reference materials make these samples useful for future geochemical studies of kimberlitic rocks.     

New ICP‐MS Results for Trace Elements in Five Iron‐Formation Reference Materials

Iron formations (IFs) typically contain low mass fractions of most trace elements, including the rare earth elements (REE), and few publications describe analytical methods dedicated to this matrix. In this study, we used bomb and table‐top acid dissolution procedures and ICP‐MS to determine the mass fractions of trace elements in IF reference materials FER‐1, FER‐2, FER‐3, FER‐4 and IF‐G. The full digestion of the IF samples with the bomb procedure required the addition of a small amount of water together with the acids. The results obtained by this method mostly agreed statistically with published values. The most remarkable exception was the higher values obtained for the heavy REE in FER‐3. The recoveries of the REE obtained with the table‐top procedure were slightly higher than those of the bomb digestion, except for the values of the heavy REE in FER‐3 and FER‐4, which were up to 30% lower than published values. Sintering of the samples with sodium peroxide was performed to determine the REE, but the results tended to be lower than those derived following acid digestion. On the whole, the recoveries showed dependence on the conditions of digestion, but subtle differences in trace mineral composition between samples also exerted influence on the analytical results for trace elements.     

Elements’ Geochemical Characteristics of PM10 and PM2.5 in Beijing During Winter and Spring

From 2012 to 2013, heavy haze frequently hit Beijing in spring and winter. The fine atmospheric particulates can be inhaled by people, and remain in the respiratory tract and lung for quite a long time. The heavy metal elements in the particles are harmful, and even carcinogenic to human bodies. Therefore, it is necessary to master the geochemical characteristics and the temporal and spatial distribution of the heavy metal elements in atmospheric particles. The atmospheric particulates (TSP/PM₁₀/PM_2.5) were collected by using TH1500C intelligent medium volume (80~120 L/min) air samplers in the five functional areas and suburbs of Beijing, respectively in January 2013 (heating period) and April 2013 (non-heating period). The five functional areas were: building materials factory area, residential area, education area, business area and recreation area, each functional area having three sampling sites, and five in suburbs. The sampling height was 1.5 m above the ground and the distance of the sampling sites to roads exceeded 50 m so as to avoid excessive impact of vehicle exhaust emissions. These samples were analyzed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), Inductively Coupled Plasma Optical Emission Spectrometer(ICP-OES)and Atomic Fluorescence Spectrometer (AFS), by which 21 elements including Al, Fe, Mn, As, Hg, Cd, Cr were tested. Based on the comparisons of the concentration and element content variation of atmospheric particulates of these functional areas in and after the heating period, the spatial distribution of atmospheric particulates and the influence of coal combustion on the concentration and composition of atmospheric particulates were revealed. The elements sources of atmospheric particulates were also discussed by computing the enrichment factor of the elements, providing a scientific basis for the air contaminant treatment in Beijing. The results showed that the total concentration of the 21 elements of PM₁₀ and PM_2.5 in the functional areas of Beijing in winter was higher than that in spring, the most marked among them being the business area. In winter, the concentration of pollution elements in the building materials factory area and the business area in Beijing was extremely high, and the residential area, education area, recreation area and suburbs where people live were much better, among which the education area was the best. The concentration change of particulates in suburbs was quite smaller in winter and spring than that of the urban area. It also showed that the concentrations of Cd, Cr, As and Hg in PM₁₀ increased by 233%,306%,298%,141%,respectively and the increase in PM_2.5 was 442%、309%、310%、256%, respectively. These abovementioned elements show a tendency to accumulate mainly in PM_2.5 whose concentrations in winter were significantly higher than those in spring. It indicates that coal heating during winter makes great contributions to the polluting elements in atmosphere and the main polluting particulates are Cd, As and Hg.     

高压密闭消解-电感耦合等离子体质谱法测定海洋沉积物中稀土元素

样品用HNO3-HF高压密闭消解,电感耦合等离子体质谱测定海洋沉积物中15种稀土元素。研究了消解方法、酸体系和质谱干扰对稀土元素测定的影响。结果表明,相比于电热板消解和微波消解,高压密闭消解具有酸用量少、消解完全、消解过程损失少等优点;HNO3-HF体系能有效地分解海洋沉积物样品;利用干扰离子校正方程,能有效地校正Ba和轻稀土元素所形成的多原子离子干扰。15种稀土元素的方法检出限为3～15 ng/g。使用水系沉积物标准物质GBW 07309和GBW 07311、海底沉积物标准物质GBW 07313进行验证,测定值与标准值基本吻合,相对标准偏差和相对误差均低于5%。方法用于长江口沉积物样品的测定,精密度(RSD,n=6)小于5%,加标回收率为95.8%～104%。该方法检出限低,精密度和准确度高,适用于大批海洋沉积物样品的分析。     

正态分布在区域地球化学调查样品分析质量评价中的应用探讨

区域地球化学样品长期以来一直是采用间接方法对实际样品元素分析质量进行评价,有效地提高了区域地球化学样品的整体分析质量,但是当实际样品和外部质量控制样品含量范围差别较大时,间接评价的效果会减弱。本文从区域地球化学样品大部分元素符合标准(对数)正态分布的规律出发,运用SPSS、Excel等软件对区域地球化学调查样品元素含量正态分布情况进行研究,通过计算元素含量实际正态分布图和标准正态分布图的重合度直接评价元素的分析质量。运用整套方法对实验室分析的江西某地多目标区域地球化学样品的分析数据进行了质量评价,正态分布检验表明微量元素需要通过对数转换才能进行正态分布分析,该地区钛、钨、铬等元素不适合用本方法进行质量评价;钴、汞、镓等18个元素的重合度都在0.9以上;氧化钙和氧化钠重合度小于0.9,样品实际结果分析表明需降低分析方法检出限,提高低含量氧化钙和氧化钠的分析质量。本方法对区域地球化学调查样品的分析数据质量的直接评价作了有益的尝试,可以作为现有区域地球化学调查样品质量评价办法的参考和补充。