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1.
Neutron-activation analysis /NAA/ was used for the estimation of Hg, Co, Cr, Zn and Fe in leaves of various plants namelySapindus mukorossis, Alstonia scholaris andDiospyros embryopteris located in urban areas of Punjab, Pakistan. Different varities of tissues were found to have different concentration of trace elements when compared among themselves. Significant pollution has been observed.  相似文献   

2.
A method is described for the determination of trace metal ions, V, Al, Cu, Mo Zn, and U, in natural water samples by neutron activation analysis, using organic coprecipitation as a preconcentration method. The preconcentration of trace elements was accomplished by converting the dissolved trace metal ions into the oxine chelates atpH 5.2 and extraction of the chelates witho-phenylphenol which is a liquid above 56 °C and solidifies at room temperature. After cooling the extraction system, the fine particles of the organic phase were collected on a millipore filter and the precipitate was air-dried in a clean environment. The solid extract was wrapped up in a sheet of clean polyethylene and subjected to neutron irradiation in a reactor for less than 10 min at a thermal flux of 2·1013 n·cm−2·sec−1. γ-Ray spectrometry by a coaxial Ge(Li) detector connected to a 1024-channel PHA was performed on the irradiated sample without further chemical separation, and thus the ppb level concentration of the elements in natural water samples could be determined. The fundamental study of the collection of the trace elements is also described.  相似文献   

3.
The k 0-standardization method of NAA is known as one of the most remarkable progress of NAA with its many advantages. Recently, our laboratory is highly involved in various areas of application of k 0-NAA. This paper focuses on the application of the k 0-NAA method in Nutritional and Health-Related Environmental field. Tobacco holds a leading position among different commodities of human consumption. The adverse health effects of toxic and trace elements in tobacco smoke on smokers and non-smokers are a special concern. In the present study, the concentration of 24 trace elements in cigarette tobacco of five different brands of Algerian and American cigarettes have been determined by k 0-based INAA method. The results were compared with those obtained for samples from Iranian, Turkish, Brazilian and Mexican cigarettes tobacco. To evaluate the accurate of the results the SRM IAEA-140/TM was executed. The analytical results showed that the relative error of most of the elements was less than 10%.  相似文献   

4.
Changes in analytical line intensities of some trace impurities of p and d elements in the iron oxide–graphite powder system were studied at different concentrations of iron in the system. The unfavorable effect of changes in the iron concentration on the results of analysis was revealed, and recommendations for its elimination are given.  相似文献   

5.
This study aimed to develop a precise and accurate method of sample preparation of Auricularia auricula for inductively coupled plasma-optical emission spectrometry-based trace element determination and to compare concentrations of seven trace elements (Mg, Fe, Mn, Zn, Ni, Cr, Sr) in six A. auricula samples belonging to three varieties with two cultivation substrates. Five sample preparation procedures, microwave-assisted digestion, nitric acid digestion with hot plate heating, nitric acid and perchloric acid digestion with hot plate heating, nitric acid digestion with ash content, and aqua regia digestion with ash content, were compared. The performance of the procedures was determined based on the precision and accuracy of the results and the limits of detection of the elements. The best results, with limits of detection of 0.60–6.60?ng?·?mL?1 and recoveries for spiked samples between 93.80 and 105.00%, were found using nitric acid digestion with ash content. Six A. auricula samples were analyzed using the proposed procedure. Among the tested elements, the concentration of Fe was highest in all six A. auricula samples up to a maximum concentration of 284.83?µg?·?g?1. The concentrations of Mn, Cu, and Ni increased in mixed stands (basswood, birch, and mongolica) compared with pine sawdust cultivation.  相似文献   

6.
Concentration of four trace elements (copper, zinc, iron, and selenium) was determined in colon tissue from twenty-three patients with colorectal cancer. The tissue samples were dried and dissolved using microwave-assisted digestion technique. The content of trace elements was determined using atomic absorption spectrometry. No significant differences between Zn levels in normal and cancerous tissues were observed. However, the levels of Cu, Fe, and Se were significantly higher in cancerous tissues than in the control samples. The results obtained sing microwave-assisted technique were compared to those obtained via alkaline digestion with tetramethylammonium hydroxide. Both techniques were used for the digestion of certified reference material of pork liver. Very good agreement with the certified values of Cu, Fe, and Zn in the reference material was achieved using alkaline digestion procedure. This technique seems to be an efficient alternative to decomposition of biological samples.  相似文献   

7.

The objective of this study is a quantitative and qualitative analysis of essential and trace elements of four indigenous Ethiopian spices and herbs using instrumental neutron activation analysis technique. Results obtained for 16 elements: Major elements; Mg, Cl, and K; Minor elements; Na, Fe, and Mn, Zn, Br. While Al, V, Sm, Sc, La, Ba, Eu, Rb were found in traces. The spices, Affromumom korarima and Lippa Adonesis var. Koseret sebsebe were found to be very good sources of essential trace elements like Fe, Zn and Mn. The highest concentration of Mg was found in Ajowan whereas K and Fe were measured in Coriander seeds. The average daily dietary intake of some essential elements from the use of these spices were found to be below the recommended upper limit by WHO.

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8.
Summary Guanabara Bay, located at Rio de Janeiro, is an example of an impacted coastal environment due to the high influx of industrial and domestic effluents. Four sediment cores were sampled in areas with different levels of pollution and were analyzed for trace elements and foraminifera for abundance. Instrumental neutron activation analysis (INAA) was used to determine As, Ba, Co, Cr, Fe, Sb, Sc, and Zn. The effects of metal concentrations in the benthic foraminifera were studied. The low concentrations of the benthic foraminifera and the dominance of opportunistic species in coastal regions such as Ammonia may be correlated to natural stress or anthropogenic impact.  相似文献   

9.
The compositional changes of inorganic elements on freshwater leaching of 35 species of Chinese algae were studied by the determination of the element contents in marine algae using instrumental neutron activation analysis. It was found that alkali metals and chlorine mainly exist as ions in algae, in which, water-soluble K and Na exist as chlorides. While, other elements exist as the states of both ions and organic combination in which the water leaching ratios of alkaline earth metals are the lowest. The combination of trace elements with various organic macromolecules inSargassum kjellmanianum was also studied using neutron activation analysis combined with chemical and biochemical separation techniques. The results indicate that the concentration of many trace elements, such as Zn, Fe, Sc, Th are earths in protein are quite high, and some trace elements can also be combined by pigment and polyphenol. Alkaline earth metal mainly bind with alginic acid inSargassum kjellmanianum.  相似文献   

10.
利用全谱直读等离子体发射光谱法(ICP-AES)测定了3种秦艽组植物10种微量元素(Cu,Zn,Fe,Mn,Ni,Co,Sn,V,Al,Ti)的含量,并进行了比较分析。结果表明,所测定元素在3个不同物种内的含量排列顺序基本一致,显示了三者在元素富集方面的相似性。就同一种元素在3个物种内的富集水平而言,以麻花艽根部具有较高含量的元素Cu,Zn,Co,Al和Ti,管花秦艽根部则大量富集了其余5种微量元素,达乌里秦艽对元素的吸收积累能力居中,揭示了不同物种对同一元素富集能力的差异。该研究可为秦艽类植物资源的深入开发利用提供参考。  相似文献   

11.
The processes were studied of the solvent extraction of the ions of triply-charged trace elements including scandium, indium, gallium, and yttrium, as well as iron, with N-octyl-N,N-bis(dihexylphosphinylmethyl) amine solution in toluene, chloroform or methylene chloride from hydrochloric, nitric or perchloric acids aqueous solutions. The metals extraction dependence on the acid concentration showed that the best results were reached using perchloric acid. The calculation of partition coefficients of metals allowed us to reveal a high selectivity of the scandium extraction. The prospects of using the investigated bisphosphinylamine in the technology of extraction, concentration and separation of the trace metals ions was concluded.  相似文献   

12.
Summary This study determined bromine, iron, scandium and zinc serum levels in Taiwanese aboriginal preschool children living in remote mountainous areas to increase the understanding of the social, cultural, nutrient and ethnic background of the Taiwanese children. Seventy-three serum samples were taken from two ethnic groups of preschool children, Atayal aborigines (AAPC) and Bunun aborigines (BAPC). Sera of these children were freeze dried. Trace elements in sera were identified by instrumental neutron activation analysis (INAA). The accuracy and precision of INAA was evaluated using certified reference materials: Tomato Leaves (NIST-SRM 1570a) and Lichen (IAEA-336). Statistical analysis identified several different patterns for ethnic groups, gender and age via the two-tailed Student's t-test. Analytical results showed that the ranges of Br, Fe, Sc and Zn in sera were somewhat wide. The Zn serum levels (p<0.05) and Br serum levels (p<0.01) in the AAPC were significantly lower than those in the BAPC. However, there were no significant differences in Fe or Sc serum levels between the two groups. Analytical results were compared to published data for different counties. This study is the first investigating trace elements in Taiwanese aborigines and can be used to establish a much-needed serum element database.  相似文献   

13.
In a study of the atmospheric deposition of trace elements in different parts of Norway, samples of the mossHylocomium Splendens were analyzed with respect to 28 elements. The determination of Cu, Zn, Cd, and Pb was carried out by atomic absorption spectrophotometry, while 24 additional elements were determined by instrumental neutron activation analysis. In samples from southernmost Norway, a substantially higher concentration was found for elements such as Pb, Sb, V, Cr, Cu, Zn, As, Se, Mo, Ag, and Cd than in samples from places located in the more northerly parts of the country. The results indicate that sources which are to the south and south-west of Scandinavia, contribute significantly to heavy metal deposition in Norway.  相似文献   

14.
An electrothermal atomic absorption method (ETAAS) for the direct determination of trace elements (Cd, Cr, Cu, Mn, Se) both in blood fractions (erythrocytes, plasma and lymphocytes) and whole blood was developed. Zeeman background correction and graphite tubes with L’vov platforms were used. Samples were ¶diluted with HNO3/Triton X-100 and pipetted directly ¶into the graphite tube. Ashing, pretreatment and atomization steps were optimized carefully for the different fractions and elements applying different matrix modifiers ¶for each element. For the lymphocyte fraction a multi-fold injection technique was applied. Low detection limits ¶of the ETAAS method (Cd 0.13 μg/L, Cr 0.11 μg/L, ¶Cu 0.52 μg/L, Mn 0.13 μg/L, Se 0.7 μg/L of whole blood) combined with small quantities of sample necessary for analysis allow determination of trace elements in this matrix. Verification of possible differences in the trace element status of humans was performed with statistical significance (P < 0.05). In addition, a contribution to the determination of normal values of essential elements was achieved. The method was applied for determination of trace elements in human blood and blood fractions of two groups (n = 50) different in health status.  相似文献   

15.
The feasibility of using two different microwave-based sample preparation methods was investigated to determine the total and water-soluble trace metal fraction in airborne particulate matter. The extraction techniques were then applied to urban particulate matter of different sizes in order to evaluate their bioavailability of associated trace metals. While a combination of HNO3-HF-H2O2 was used for the total trace metal fraction of particulate matter, water was employed for the microwave-assisted extraction of water-soluble trace metal fractions. Inductively coupled plasma-mass spectrometry (ICP-MS) was used for the analysis of trace elements. The experimental protocol for the microwave assisted digestion was established using two different SRMs (1648, urban particulate matter and 1649a, urban dust). In the case of water-soluble trace metal fraction, the quantities extracted from the SRMs were compared between ultrasonic and microwave-assisted extractions, and there was a good agreement between the two extraction methods. Blanks values and limits of detection (LODs) for total and water-soluble trace metal concentrations were determined for three different filter substrates (Teflon, Zeflour, and Quartz). Subsequently, the proposed digestion method was evaluated for its extraction efficiency with these filter substrates. Finally, the real-world application of the proposed microwave-based sample preparation methods was demonstrated by analyzing trace elements in airborne particulate samples collected from different outdoor environments in Singapore. The solubility of 11 trace elements detected in the particulate samples is quantified.  相似文献   

16.
Neutron activation analysis (NAA) was used to determine the concentration of trace elements in 44 precious and 52 common opals sampled from a number of recognised fields within Australia. The purpose of this study was to determine if precious and common opals of the same colour and location have the same or a different trace element profile. Similar numbers of black, white and grey samples were studied in each case. In most cases common opals had a significantly higher concentrationof certain trace elements when compared with precious opals.  相似文献   

17.
The uptake of Cr, Mn, Ni, Cu, Zn, Cd and Pb in soft tissue of Perna perna mussels and their shells has been studied in aquarium experiments in which mussels were exposed for 30 or 60 days to seawater spiked with different concentrations of these contaminants (125 and 500 μg L−1). Tissue samples were analyzed after acid digestion by conventional solution nebulization ICP–MS. Laser ablation ICP–MS was used for the quantitative determination of trace elements in different areas of the corresponding shells. With the exception of Mn and Zn, all other elements studied showed a significant concentration enhancements in soft tissue, with the magnitude of this enhancement following the order: Cr > Ni > Cd > Cu > Pb. A corresponding increase in most contaminants, although less pronounced, was also observed in the newly formed growth rings of mussel shells, contributing to the validation of Perna perna mussel shell as a bioindicator of toxic elements.  相似文献   

18.
The concentration of five trace elements Cr, As, Pb, Rb and Sr in seven medicinal plants Garcinia indica, Ficus benghalensis, Flacartia Montana, Nyctanthes arbor-tristis, Morinda citrifolia, Ficus recemosa, Barringtonia acutangula and associated soils were analyzed using ICP-MS. In plant the elemental concentrations of Cr, Pb, Rb and Sr vary widely and in soil the elemental concentrations of Cr, As and Sr showed wide variation. Selective enrichment of elements Rb and Sr was observed in some plants. The soil to plant transfer ratio was significant for Sr. The results of these systematic investigations are presented and discussed in this paper.  相似文献   

19.
不同颜色果实唐古特白刺叶中矿物质元素含量的比较   总被引:1,自引:0,他引:1  
通过采用ICP-MS检测了柴达木盆地3种不同颜色果实唐古特白刺叶中11种矿物质元素. 结果表明不同颜色果实唐古特白刺叶中矿物质元素存在差异. 唐古特白刺叶中常量元素以Na元素最高,其中以紫色果实白刺叶中Na元素和常量元素总量最高,大红果白刺叶最低. 微量元素在白刺叶中以Fe元素含量最高,其中以紫红果白刺叶中Fe元素和必需微量元素总量最高,紫色果含量最低. 另外,有害元素Pb和Cd在3种颜色果实的叶子中含量均较低. 方法简便快速,结果准确可靠,可以为不同颜色果实唐古特白刺叶子的应用提供基础数据.  相似文献   

20.
Three watersheds were studied by sampling bulk precipitation deposition, seepage water at 50 cm soil depth and spring water. As the main analytical method for determination of trace elements and heavy metals in water samples, thek 0-based method of INAA was used. The results showed an increased content and concentration range of trace elements in precipitation, soil water and spring water in the vicinity of the otanj Thermal Power Plant. We demonstrated that thek 0-based method of INAA as a multielement nondestructive technique is a highly suitable approach to determining some toxic trace elements in environmental studies of the water cycle.  相似文献   

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