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1.
The Bouregreg river is one of the main rivers of Morocco, Its source being located in the Moroccan Central Massif and flows towards the Atlantic coast through the coastal Meseta. The Bouregreg river basin is located in the Moroccan Central Massif which consists mainly of Palaeozoic formations that were subject to the Hercynian orogeny. To evaluate the environmental status of the Bouregreg river water, sampling of the dissolved (<0.22 μm) and suspended (>0.22 μm) phases was performed at 10 sites along the Bouregreg river and its tributaries in the winter of 2005. Major (Na, Ca, K, Ti, Mn, Al and Fe), trace (As, Ba, Bi, Cd, Co, Cr, Cs, Cu, Hf, Li, Mo, Nb, Ni, Pb, Rb, Sb, Sc, Sn, Sr, Ta, Th, U, V, W, Y, Zn and Zr) elements and rare earth elements were analysed. The dissolved and particulate phase of the Bouregreg river draining these contrasting zones show similar characteristics to those observed in other major tropical rivers such as the Congo and Amazon, and vary in composition between the different source areas. Obtained data show that the spectra of the standardized concentrations for all the determined elements in the dissolved and the suspended phase have the same form whatever the station and that the whole of the elements is strongly deficient compared to the upper continental crust. The strong depletion in the suspended phase and the associated enrichment in the dissolved phase suggest that some elements such as Rb, Ba and Sr are the most mobile elements during the weathering processes. The removal of the most mobile elements from the bedrock concentrates all remaining elements in the weathered phases of the soils, from whence it can be removed mechanically. As and Sb are strongly enriched as well in the dissolved load as in the suspended load.  相似文献   

2.
Aiming at distinguishing between the sedimentary environments in shallow sea using elemental geochemical markers, the determinations of trace elements in carbonate rocks by thermal neutron, epithermal neutron and short-irradiation activation analysis have been studied, and more than 30 major and trace elements determined. Al, Cl, Sc, Ti, V, Cr, Fe, Co, As, Br, Rb, Sb, Cs, Lu, Hf, Ta, Th and U were found to be the effective distinguishing markers for the secondary environments in shallow sea.  相似文献   

3.
用仪器中子活化分析技术,测定了南极岩石中8种稀土元素含量,讨论了不同岩石的稀土模式特点。  相似文献   

4.
采用脱矿物质、提取腐殖酸等方法结合ICP-MS对伊敏15、16煤中的32种微量元素的含量及其赋存特征进行了分析。与地壳克拉克值及中国侏罗-白垩纪煤和世界褐煤中微量元素含量相比,伊敏褐煤中微量元素没有明显富集。脱矿物质处理后,Ni明显富集,As略比原煤高,其他微量元素都低于原煤。原煤提取腐殖酸和脱矿物煤提取腐殖酸中Ni、Mo、Cd、Sn、W明显富集,这表明Ni、Mo、Cd、Sn、W和腐殖酸形成了稳定的有机态化合物。原煤提取腐殖酸残煤和脱矿物煤提取腐殖酸残煤中V、Ni、As富集,表明V、Ni、As与煤的大分子结构形成了稳定的有机态化合物。根据微量元素和灰分的相关性系数,把微量元素分为以下几类:无机富集元素Cr、U;亲无机元素Cu、Cd、In、Sn、Ga、Y、Zr、Hf、Bi、Th;偏无机元素Be、Sc、Rb、Sr、Nb、Cs、Ta、Pb;偏有机元素V、As、Tl、Ba、Se;亲有机元素Li、Co、W;有机富集元素Ni、Zn、Mo、Sb。  相似文献   

5.
The vertical profiles of two major elements (Na and Ca) and 24 trace elements (Rb, Cs, Sr, Ba, Sc, La, Ce, Sm, Eu, Tb, Yb, Lu, Th, U, Hf, Nb, Ta, Cr, Fe, Co, Zn, As, Sb and Br) have been investigated by neutron activation analysis in a 2.5 m core collected from the Danube Delta, Matita Lake. The data have been correlated with the concentrations of five major minerals (calcite, dolomite, feldspar, clay and quartz) as determined by X-ray diffration. This study revealed the presence of As, Sb and Br as pollutant microelements.  相似文献   

6.
Major, minor and trace element mass fractions were determined using wavelength dispersive and energy dispersive X-ray fluorescence and instrumental neutron activation analysis for five clay certified reference materials (NCS DC 60102–60105, 61101) distributed by the National Research Center for Certified Reference Materials in China. We report mass fractions for 10 major and the following 29 minor and trace elements: As, Ba, Ce, Co, Cr, Cs, Cu, Eu, Hf, La, Lu, Nb, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, U, V, Y, Yb, Zn, and Zr.  相似文献   

7.
Water hyacinth (Eichhornia crassipes) is known to accumulate elements from rivers and a good tool for water monitoring. To test the usefulness of such an aquatic plant as a bioindicator, we have determined the levels of Na, Ca, Cr, Fe, Co, Zn, As, Rb, Zr, Sb, Cs, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, Th, and U in water hyacinth around industrial facilities and along the studied area by instrumental neutron activation analysis. The concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, and Pb were determined in upstream river water and effluent factories. Contamination factor, and pollution load index was calculated. The results show that higher concentrations as well as bioaccumulation factors of these elements were observed in water hyacinth samples around the industrial facilities. On the other hand a decrease in calcium concentration was observed as a result of the thermal pollution of Nile river water. The pollution load index for the studied area was estimated to be 4.2.  相似文献   

8.
Concentrations of major and trace elements in volcanic rock and soil samples, including geological standard reference materials, were determined by neutron activation analysis (NAA) and prompt gamma activation analysis (PGAA), both using the k 0-standardization method. The paper highlights the different experimental procedures, such as sample preparation, data collection and spectrum evaluation. In geological samples, PGAA gives precise results for major elements (Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K and—as a unique method—for H), for some of the light trace elements as B and Cl, as well as for Sc, S, Cr, Co, Ni, Cd, Nd, Sm and Gd. NAA is sensitive for the rare earth elements, and for many major (Ti, Al, Fe, Mn, Mg, Ca, Na, K) and trace elements (e.g.: Sc, V, Cr, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, As, Sb, Ce, Ba, Hf, Ta, W). For most major elements the results obtained by the two methods show good agreement. The comparison of the results obtained for trace elements is not always possible, since PGAA is less sensitive and concentrations are often below its detection limits. Nevertheless, the complementarity of NAA and PGAA allows nearly panoramic analysis of geological materials.  相似文献   

9.
Instrumental neutron activation analysis has been applied for the determination of 20 minor and trace elements (As, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Na, Rb, Sb, Sc, Sm, Ta, Tb, Th, Yb and Zn) in two groups of potsherds which had been excavated at two different sites of Greece, the islands of Thasos (Group A) and Delos (Group B). A good agreement for all the elements examined between the pottery specimens of Groups A and B was found. The matching in chemical composition between the stylistically related potteries of Group A (Thasos) and Group B (Delos) provides strong support for the archaeologist's hypothesis that the two groups of potsherds belong to the same major group of “melian” pottery.  相似文献   

10.
The vertical profiles of 4 major (Na, K, Ca and Fe) and 17 trace elements (Rb, Cs, Ba, Sc, La, Ce, Sm, Eu, Tb, Yb, Lu, Th, U, Hf, Ta, Co and Cr) have been investigated in cores collected from three lakes: Lung, Mesteru and Furtuna, all of them situated in the Fluvio-lacustrine region of the Danube Delta. All profiles are characterized by a relatively uniform distribution of these elements. The total rare earth elements to Sc correlation, as well as their concentrations normalized to the upper continental crust, determine the continental origin of these sediments.  相似文献   

11.
Thirty four elements (Al, As, Ba, Br, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Gd, Hf, Ho, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, Ti, U, V, W, Yb) were determined by instrumental neutron activation analysis in the second set of Chinese geochemical standard reference materials (sediments from GSD-9 to GSD-12, soils from GSS-1 to GSS-8, rocks from GSR-1 to GSR-6) using both thermal and epithermal irradiations. Irradiation schemes designed to utilise short, medium and long-lived nuclides were employed in order to analyse major, minor and trace elements with different half-lives. The gamma-ray spectra were measured by Ge(Li) and HP(Ge) detectors. Relevant nuclear data and possible interferences are listed, and analytical results are presented and discussed.  相似文献   

12.
采用辉光放电质谱法(GD-MS)测定高纯钛中Mg、Al、Cr、Fe、V、Mn、Co、Ni、Cu、Zn、As、Sn、Sb、Ta、W、Pb、Bi等痕量杂质元素,并对GD-MS工作参数及条件进行了优化。主要元素与内标校正ICP-MS法定量分析的结果一致,对结果差异的原因进行分析,论述了Element GD辉光放电质谱仪在痕量杂质元素分析方面的优势。  相似文献   

13.
This work presents the results obtained on suspended particulate matter (SPM) collected from the rivers Volturno and Garigliano and from the sea stretch between the mouth of the Volturno river and the Sabaudia lake (Central Tyrrhenian Sea). The elements As, Au, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, La, Lu, Mn, Rb, Sb, Sc, Se, Sm, Ta, Th, W and Yb were determined by instrumental neutron activation analysis. The results show that the element concentrations in SPM tend to be higher in surface than in bottom samples. Also, enrichment factors (EF's) were calculated with respect to Sc assumed as representative of alumino-silicates. Higher values of EF's were found for Zn, As, Se, Sb, Hg, W, and Au.Work partly carried out under the contract No. BIO-B322-I (S) of the Commission of the European Communities.  相似文献   

14.
Samples of the mosses Hylocomium splendens and Pleurozium schreberi, collected in the summer of 1998, were used to study the atmospheric deposition of heavy metals and other toxic elements in the Chelyabinsk Region situated in the South Urals, one of the most heavily polluted industrial areas of the Russian Federation. Samples of natural soils were collected simultaneously with moss at the same 30 sites in order to investigate surface accumulation of heavy metals and to examine the correlation of elements in moss and soil samples in order to separate contributions from atmospheric deposition and from soil minerals. A total of 38 elements (Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Rb, Sr, Zr, Mo, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Hf, Ta, W, Au, Th, U) in soil and 33 elements Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, Ba, La, Ce, Sm, Tb, Yb, Hf, Ta, W, Au, Th, U) were determined by epithermal neutron activation analysis. The elements Cu, Cd and Pb (in moss samples only) were obtained by atomic absorption spectrometry. VARIMAX rotated principal component analysis was used to identify and characterize different pollution sources and to point out the most polluted areas.  相似文献   

15.
Samples of the mussel Mytilus edulis were collected from different sites of estuarine and coastal areas of the North Sea and the Baltic. The following elements were determined by INAA: Ca, Sc, Cr, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Ag, Cd, Sn, Cs, Ba, Ta, Eu, Tb, Yb, Hf, Au, Hg, Th. Multielement correlation analysis was used for the evaluation of the data. Differences in trace element patterns are found and described calculating trace element ratios. Regional differences in trace element concentrations are superimposed by typical seasonal variations, with highest concentration levels found in late winter and spring, and lowest in summer and autumn. With support of Deutsche Forschungsgemeinschaft  相似文献   

16.
A radiochemical neutron activation analysis has been applied to 2N–4N grade titanium metal and its oxide. Twenty two impurities were separated in a group from scandium by a radiochemical separation method using cation exchange resin with HBr and HCl. The contents of the elements were calculated by a single comparator method using two monitors. The analytical results agree well within 10% deviation with those obtained by instrumental method. Eighteen elements, Na, Fe, Co, As, Se, Sr, Mo, Sb, La, Eu, Tb, Yb, Lu, Hf, Ta, W, Th and U, are determined in titanium oxides and 17 elements, Na, Cr, Fe, Co, Se, As, Zr, Mo, Sb, Cs, Ce, Tb, Yb, Hf, Ta, W and Th, in titanium metals.  相似文献   

17.
The concentration of 24 trace elements in the tobacco of two different brands of Iranian cigarettes, “Zarrin” and “Oshnoo”, has been measured by neutron activation analysis employing a high-resolution Ge(Li) detector. These elements are: Na, K, Sc, Cr, Mn, Fe, Co, Zn, Se, Br, Rb, Ag, Sb, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Au, Hg and Th.  相似文献   

18.
The concentration of thirty-four elements in twelve coffee brands has been measured using instrumental neutron activation analysis. The samples investigated included four brands of commercially available ground coffee and eight brands of soluble/instant coffee. The elements measured were Al, As, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Gd, Hf, K, La, Lu, Mg, Mn, Na, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, Tm, U, V, Yb and Zn. Twenty four elements were found to be below the detection limit in one or more samples. These elements were Ce, Cr, Fe, V, As, Eu, Ba, Dy, Gd, Hf, La, Lu, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, Yb, Tm, and U.  相似文献   

19.
ICP-MS has been used for the determination of over 30 geochemically significant trace elements (Sc, V, Cr, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Cs, Ba, Hf, Ta, Pb, Th, U and REEs) in anorthosites and related rock reference samples. Open acid digestion, pressure decomposition using HF, HNO(3) and HClO(4), and a fusion method using lithium metaborate and subsequent dissolution in dil. HNO(3) were adopted for the decomposition of these rock samples before analysis. The dissolution problems and interference effects are discussed. Rh and Bi were used as internal standards. The first set of data on several rare earths and other trace elements in the Russian anorthosite reference sample, MO-6 are presented along with data on other samples. The data are compared with the available data. The results obtained with different dissolution methods were found to be in good agreement for the majority of the trace elements. The accuracy and precision achieved (better than 6% RSD in most cases) suggested that the data obtained by ICP-MS for such samples are best suited for geochemical interpretations.  相似文献   

20.
Instrumental neutron activation analysis (INAA) was applied to thedetermination of the concentration levels of Na, Mg, Al, Cl, K, Sc, Ti, V,Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Cd, Sb, I, Cs,Ba, La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Lu, Hf, Ta, Hg, Th and U in three radiopharmaceuticals.The irradiation of the samples was carried out in a 0.5 kW Bariloche RA-6Research Nuclear Reactor and the induced gamma-activity was measured by gamma-spectrometry.INAA proves to be an accurate and precise technique to obtain a quick informationon the concentration levels of several minor and trace components in radiopharmaceuticals.The quantification of heavy toxic elements is required for the registrationof radiopharmaceuticals.  相似文献   

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