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1.
ABSTRACT

Heavy metal air pollution in Romania was investigated by using passive moss biomonitoring. This study is a component of an international UNECE ICP Vegetation Program – moss survey. A total of 330 samples of Hypnum cupressiforme, Hylocomium splendens, Pleurozium schreberi, and other mosses were collected in Romania in the summer and autumn of 2010. The concentrations of aluminum, cadmium, chromium, copper, iron, lead, nickel, vanadium, and zinc were determined by graphite furnace/flame atomic absorption spectrometry and instrumental neutron activation analysis. The results were statistically processed to obtain spatial distribution maps of factor scores based on elemental concentrations in the moss, together with the spatial distribution maps of heavy metals in moss. The median concentrations of cadmium, 1.20?mg/kg dry weight, and lead, 30.8?mg/kg dry weight, were high compared with other European countries. The results revealed that the atmospheric deposition of these metals is a problem in north and northwest Romania.  相似文献   

2.
采用多种方法对同一种茶叶进行消解,用原子吸收光谱法测定不同方法消解的茶叶中有害微量元素铅和镉的含量并进行对比,探索了茶叶中微量元素铅和镉低损耗的最佳消解条件.实验结果表明,不同的消解方式对茶叶中微量元素的测定结果影响很大.测定茶叶中铅和镉元素时,采用硝酸-高氯酸加盖浸泡过夜方法较为理想.  相似文献   

3.
The content of various heavy metals (arsenic, cadmium, chromium, copper, iron, lead, mercury, nickel, manganese and zinc) in the moss species Rhodobryum ontariense (Kindb.) Kindb. and its tea are presented in this study. Pursuant to the use of this tea in traditional Chinese medicine for hypertension, the aim of this study was to examine its safety in regard to the metals. All heavy metals were determined by adequate EPA methods. The concentrations of all metals for daily intake in its tea were below the safety levels for human consumption. These results indicate the importance of manganese in R. ontariense tea traditionally used for hypertension and other heart disorders.  相似文献   

4.
Abstract

Lead, cadmium and mercury were determined in sediments and mussels, and the ability of these indicators to record metal variations in coastal marine environment is described in this work. The results of an extended investigation of the status of three gulfs at Northern Greece are given, regarding the content of these metals in surface sediments and Mytilus galloprovincialis. The samples were collected during a four-year period. The total concentration of the above heavy metals was determined after digestion of the samples by suitable mixtures of acids, including nitric, perchloric and hydrofluoric acid. The digestion was carried out in a steel pressurised bomb with closed teflon vessels. Lead and cadmium were determined by means of electrothermal atomic absorption spectrometry (ETAAS), and mercury by cold vapour atomic absorption spectrometry (CVAAS). The results were statistically evaluated by analysis of variance, and emphasis was given to annual, seasonal and spatial sources of variation. The annual changes during the last four years and the spatial distribution of heavy metals load is also discussed.  相似文献   

5.
《Analytical letters》2012,45(1):204-212
This study investigated the distribution and concentrations of chromium, copper, arsenic, zinc, cadmium, and lead in seawater and suspended particles in the South China Sea by collection of samples from different depths at sixteen stations. The salinity, temperature, pH, dissolved organic carbon, dissolved oxygen, and silicon concentration were also measured in seawater. The results showed that the concentration levels in seawater from 0 m to 4000 m followed this pattern: zinc > arsenic > copper > lead > chromium > cadmium. Significant correlations were observed between lead and chromium and between arsenic, cadmium, and lead at r > 0.728. Very weak correlations were observed between copper and arsenic and between copper and cadmium. The concentrations of dissolved metals and particulate metals had negative correlations except for zinc. The metal concentrations in seawater and suspended particles showed different correlation behavior with salinity, temperature, pH, dissolved oxygen, dissolved organic carbon, and silicon.  相似文献   

6.
黑苦荞保健茶中重金属的分析评价   总被引:1,自引:0,他引:1  
采用原子吸收光谱法和原子荧光光度法测定了四川省凉山州某几个品牌黑苦荞保健茶中的重金属铅、镉、铬、无机砷和汞的含量,并以NY/T 1510-2007标准绿色食品麦类制品为依据,对黑苦荞保健茶重金属污染状况进行了分析评价。结果表明,黑苦荞保健茶受重金属元素污染的程度由高到低表现为铅、铬、镉、无机砷和汞,但含量均未超过国家标准规定;黑苦荞叶芽茶和全株茶的重金属污染较为严重,全胚茶未受重金属污染。  相似文献   

7.
A simple method for fabricating a metal organic framework (MOF: HKUST-1) as sorbent for selective removal of chromium (III) from aqueous solution is discussed. The structure and morphology of HKUST-1 was identified by fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), the powder X-ray diffraction (XRD) and N2 adsorption-desorption (BET) analysis. Its removal process of chromium (III) and chromium (VI) on HKUST-1 was assessed systematically under various conditions such as pH value, shaking time and initial concentration of chromium (III). At pH 6.0–8.0, HKUST-1 were selective towards chromium (III) but hardly chromium (VI). Kinetic parameters fitted well with pseudo-second-order model and adsorption progress was described by Langmuir isotherm equations and spontaneous and endothermic according to the results of thermodynamics studies (?G?<?0, ?H?>?0, ?S?>?0).  相似文献   

8.
本文通过用直接悬浊液进样原子吸收法对新鲜蔬菜中铬的测定,研究了各种实验条件,并建立了实际测定新鲜蔬菜中微量元素的方法。该法将可用于食品。  相似文献   

9.
玫瑰花茶的金属元素含量及其保健功能分析   总被引:1,自引:1,他引:0  
采用V(HNO3)+V(HClO4)=5+1对玫瑰花茶进行消解,用火焰原子吸收光谱法测定了其中金属营养元素的含量。结果表明,玫瑰花茶中含有丰富的人体所必需的金属元素,其中钾、钙、钠、镁、铁、锰、铜、锌含量分别为11.6559,6.5642mg/g,23.3147μg/g,2.0533mg/g,25.8711,20.5897,7.9107,23.2493μg/g,各元素比例有利于人体吸收,具有较高的营养保健价值,为人们选用花茶提供了一定的理论依据。  相似文献   

10.
Summary Heavy metals are incorporated in human urinary calculi during a complex pathological process. The trace metals cadmium, lead, chromium, nickel and mercury are determined with regard to significance in pathogenesis and therapy. The amounts of cadmium, lead and chromium were determined as well directly in the solid sample as after chemical digestion by Zeeman-GFAAS. Both analyzing techniques show corresponding results. Nickel could be determined after chemical digestion only, while mercury was determined by a solid sampling technique. The evaluation of the results of trace metal analysis in the pilot study of 11 urinary calculi showed increased amounts of lead and cadmium compared to the results of tartar and salivary calculi.  相似文献   

11.
Nil Ozbek 《Analytical letters》2017,50(13):2139-2146
Elemental analysis of tarhana, a traditional Turkish cereal soup, has been conducted. A new method was developed for the determination of calcium, iron, magnesium, manganese, potassium, and sodium, in tarhana by microwave induced plasma atomic emission spectrometry. A sample of 0.1?g were mineralized by microwave digestion in 10?mL of 65% HNO3. A wheat flour standard reference material (GBW 08503) was used for validation. Linear calibration using standards prepared in acid was conducted for all determinations. The limits of detection were 1.21?µg?g?1 for Ca at 393.366?nm, 0.43?µg?g?1 for Fe at 259.940?nm, 11.5?µg?g?1 for K at 766.491?nm, 0.12?µg?g?1 for Mg at 285.213?nm, 0.04?µg?g?1 for Mn at 403.076?nm, and 0.04?µg?g?1 for Na at 588.995?nm. Ca, K, Fe, Mg, Mn, and Na were determined in tarhana with values from 0.73 to 1.61, 0.016 to 0.061, 2.02 to 4.09, 0.473 to 1.414, 0.019 to 0.043, and 0.26 to 1.83?mg?g?1, respectively.  相似文献   

12.
A cloud point extraction procedure for pre-concentration and determination of cadmium and lead in drinking water using sequential multi-element flame atomic absorption spectrometry is described. 4-(2-thiazolylazo)-orcinol (TAO) has been used as complexing agent and the micellar phase was obtained using the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) and centrifugation. The conditions for reaction and extraction (surfactant concentration, reagent concentration, effect of incubation time, etc) were studied and the analytical characteristics of the method were determined. The method allows the determination of cadmium and lead with quantification limits of 0.30?µg?L?1 and 2.6?µg?L?1, respectively. A precision expressed as relative standard deviation (RSD, n?=?10) of 2.3% and 2.6% has been obtained for cadmium concentrations of 10?µg?L?1 and 30?µg?L?1, respectively, and RSD of 1.3% and 1.7% for lead concentrations of 10?µg?L?1 and 30?µg?L?1, respectively. The accuracy was confirmed by analysis of a natural water certified reference material. The method has been applied for the determination of cadmium and lead in drinking water samples collected in the cities of Ilhéus and Itabuna, Brazil. Recovery tests have also been performed for some samples, and results varied from 96 to 105% for cadmium and 97 to 106% for lead. The cadmium and lead concentrations found in these samples were always lower than the permissible maximum levels stipulated by World Health Organization and the Brazilian Government.  相似文献   

13.
采用湿法对沾化冬枣叶茶样进行消化处理,利用火焰原子吸收光谱法测定了茶中K、Na、Ca、Mg、Fe、Mn、Cu、Zn的含量.结果表明,该法的加标回收率为95.2%~104.2%,RSD≤3.35%.该法操作简单,结果准确,为开发和利用冬枣叶茶提供了一定的科学依据.  相似文献   

14.
为了填补现有方法的技术空白,本方法采用微波消解和电感耦合等离子体原子发射光谱法( ICP-AES)相结合,实现对含铜污泥中铅、锌、铬、镉、砷、镁、铝、锑量的同时测定。首先采用盐酸-硝酸-氢氟酸微波消解进行样品的前处理,消解后加入高氯酸置于电热板进行除碳并赶酸,溶样效果理想,且有效避免了高温溶样对易挥发元素砷、锑的损失,整个过程安全、高效、无损。溶样后以电感耦合等离子体发射光谱法( ICP-AES)进行测定。对含铜污泥的分解方法进行了合理选择,并对测定时的元素分析谱线及各测定元素间干扰情况等进行了讨论。该方法的加标回收率在95.31%~107.28%%,相对标准偏差(RSD)在0.31%~2.05%之间(n=7),结果表明,该方法准确度高,操作简单快捷,可同时测定多种元素,能满足批量的测定含铜污泥中铅、锌、镍、铁、镉、铬、砷、锑含量的测定要求。  相似文献   

15.
The preconcentration of chromium(III) by solid phase extraction and its determination from aqueous solutions by flame atomic absorption spectrometry (FAAS) is investigated by applying an experimental design. The optimization of the preconcentration variables such as pH of the sample solution, flow rate of the sample solution and concentration of elution solution was carried out using 23 full factorial design. The most important parameter affecting the preconcentration of chromium is the concentration of eluent. In the established experimental conditions, chromium can be determined with a relative standard deviation of 2.0% (N = 7) for a chromium concentration of 100 μg L−1. The detection limit for chromium was 1 μg L−1 (N = 20). The adsorption capacity of Amberlyst 36 is found to be 90.9 mg g−1 for chromium. Effect of other ions on the procedure was also evaluated. The method was validated by the analysis of certified reference materials (tea leaves GBW 07605 and fish tissue IAEA-407). The method was applied to the determination of chromium in waste water, dam water, carrot, parsley and lettuce. Correspondence: Ali Rehber Türker, Department of Chemistry, Faculty of Science and Arts, Gazi University, TR-06500 Ankara, Turkey  相似文献   

16.
为了解中药重金属污染情况,测定了市售常用15种中成药中重金属铅、镉、铜的含量,其中铅、镉采用石墨炉原子吸收法,铜采用火焰原子吸收法测定.结果表明,15种中成药均不同程度被这3种重金属污染,通心络中铅、镉、铜含量都已超标,桑菊感冒片镉超标,中药重金属污染问题仍然存在.  相似文献   

17.
A procedure for the determination of the aqua regia soluble content of lead, cadmium and chromium in a sewage sludge reference material (CRM 145R) by electrothermal atomic absorption spectrometry (ETAAS) is described. A comparison of the dissolution procedure proposed in the certification report, to an oven-assisted digestion and a proposed microwave digestion procedure is performed. In the ETAAS method developed, 1 g of Pt proved to be an appropriate modifier for each of the above heavy metals. Possible sources of error at each analytical step are addressed. The metal contents obtained with the proposed method are in a good agreement at 95% significance level with the certified values given for CRM 145R.  相似文献   

18.
《Analytical letters》2012,45(10):1991-2004
ABSTRACT

A method was developed for the preconcentration of copper, nickel and cadmium in water samples, prior to their determination by FAAS, using the Zn-piperazinedithiocarbamate complex (ZnPDC) loaded on activated carbon. In this method, Cu, Ni and Cd in liquid phase quantitatively replaced zinc on a ZnPDC-activated carbon solid phase. Afterwards, the metals on the solid phase were easily eluted by Hg (II) solution into aqueous phase, and were measured by FAAS. The optimum experimental parameters such as pH, sample volume, and effect of matrix ions for the preconcentration of the metals were investigated. The range of linearity 0-6, 0-5, 0-3 μgml?1, correlation coefficient 0.998, 0.996, 0.999, detection limits 15.7, 23.5, 11.8 ngml?1 and determination limits 136, 179, 98 ngml?1 in final Hg(II) solution were obtained for Cu, Ni and Cd, respectively. The proposed method has been employed for the determination of Cu, Ni and Cd in various standard metal alloys and natural water samples.  相似文献   

19.
Abstract

Extractable contents of heavy metals such as Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb and Bi in soil and plant tissue samples (fruit, leaf, twig and root) collected, along a distance of 1100 m to the West, from the surroundings of a metallurgical factory producing mainly zinc, cadmium and lead were determined by flame atomic absorption spectrometry (FAAS). In addition, the determinations of Ca and Mg, macro nutrient elements for plants, were also performed. Three extractant solutions were used for dissolution of soil samples, namely aqua regia (1 HNO3+ 3 HCl) for total metal analysis, 1 mol L?1 ammonium acetate for exchangeable metal contents, and a dilute acid mixture (0.1 M HCl in 0.025 M H2SO4) for acid soluble metal contents. A mixture of HNO3 and HClO4 was used to analyze the fruit samples. The analyses of the leaf, the twig, and the root tissue samples were made by dry ashing method. The detection limits of the metals were in the range of 0.04 to 0.45 μg/mL for all soil extracts and 0.01 to 1.50 μg/mL for the fruit samples. The recovery values for all the determinations were higher than 95%. The results obtained from the analyses of plant tissue and soil samples were evaluated using linear correlation analysis and concentration factors to identify the effect of the factory near the grape-vine area.  相似文献   

20.
“浙八味”药材中重金属铅、镉、铜含量分析   总被引:1,自引:0,他引:1  
为对"浙八味"药材质量控制和安全用药提供可靠的依据,采用灰化法处理样品,火焰原子吸收分光光度法测定了其铅、镉、铜含量。结果表明,8种药材中的铅含量为0.828 1~1.747 3 mg.kg-1,镉含量为0.116 9~0.295 0mg.kg-1,铜含量为2.519 5~8.286 4 mg.kg-1。8种药材均检出一定量的有害重金属,但含量较低,未超出国家限量标准,符合《药用植物及制剂进出口绿色行业标准》的有关规定。  相似文献   

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