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1.
The Bouregreg river basin is located in the Moroccan Central Massif which consists mainly of Palaeozoic formations that were subject to the Hercynian orogeny. This study documents the background geochemistry and hydrochemistry of the Bouregreg river basin, focusing on the distribution of major and trace elements. Rock samples were collected at nine locations along the Bouregreg River and its tributaries in the winter of 2005. Major (Al, Fe, Mn, Na, K and Ti) and trace (Rb, Cs, Sr, Sc, Ba, Cr, V, Co, Ni, Zn, As, Sb, La, Ce, Nd, Sm, Tb, Dy, Yb, Lu, Hf, Ta, Mo, Th and U) elements were analysed using instrumental neutron activation analysis. Data show that most of the geochemistry and hydrochemistry are related to regional and local geology. The geochemical heritage of geological environment in the Bouregreg river basin is very important, that results from the more compatible behaviour and the inertia of some elements during the weathering (3d transition elements (Co, Ni, Cr,…), interne transition elements f (lanthanides, Zr, Hf, Nb, Ta,…)). The geochemical homogeneity of the basin shows also heritage during the crustal accretion (magmatism-metamorphism-sedimentation) and the typology of this continental area is the same that the upper continental crust. Some anomalously high heavy metal analyses, particularly for As and Sb, may be related to anthropogenic activities.  相似文献   

2.
Summary Trace elements were determined in the surface waters of tributaries of the Sepetiba Bay, Brazil (Piraquê, Itá, S?o Francisco, Guarda, Guandu Mirim, Vala do Sangue and Engenho Novo rivers) by total reflection X-ray fluorescence using synchrotron radiation (SRTXRF). Eighteen trace elements could be determined in the dissolved and the suspended particulate phases: Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr and Pb. The elemental concentration values were compared to the values recommended by the Brazilian legislation.  相似文献   

3.
A group separation scheme has been developed for radiochemical neutron activation analysis for Ca, Cu, Zn, Ga, Rb, Sr, Zr, Sb, Cs, Ba, La, Nd, Sm, Eu, Gd, Tb, Ho, Tm, Yb, Lu, Hf, Ta, W and Th in a wide variety of silicate rocks and minerals, especially ultrabasic rocks and mafic minerals. The samples are decomposed in a hydrofluoric acid-nitric acid mixture in a PTFE-lined bomb. The soluble fluorides (Cu, Zn, Ga, Rb, Zr, Sb, Cs, Ht, Ta, W and Pa) are separated into three groups of elements by sequential elution from a cationexchange resin. The insoluble fluorides (Ca, Rb, Sr, Cs, Ba and REE) are dissolved and purified from interfering iron and scandium activities by extraction with tri-n-butyl phosphate. If necessary, the four main groups can be purified further from interfering activities such as 59Fe, 51Cr and 60Co. The accuracy and reproducibility of the procedure were tested by repeated analysis of U.S. Geological Survey standard granite G-2, andesite AGV-1 and dunite DTS-1.  相似文献   

4.
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   

5.
The three phases “dissolved solids”, “suspended solids” and “sediment” of four sampling sites along the river Isar were analysed by INAA. In these as well as in the different grain-size fractions between<2 and 63 μm 17 trace elements were determined. Compared with the values of other rivers in Middle Europe the river Isar is still below the levels of significant pollution.  相似文献   

6.
Analyses for certification have been made by instrumental neutron activation analysis (INAA) for the determination of 21 elements in the National Institute of Standards and Technology (NIST) Spinach renewal reference material, SRM 1570a. Elements determined included ones with short halflife products (Al, V, Ca, Mg), intermediate halflife products (Mn, Na, K, La), and long halflife products (Ba, Co, Cr, Cs, Eu, Fe, Rb, Sb, Sc, Se, Sr, Th, and Zn). For the first time a new robotic sample changer was used in the counting of long halflife indicator isotopes for certification of an SRM. Uncertainties obtained averaged±1.80% for the four major and minor constituents (Ca, K, Mg, Na); ±3.14% for elements with concentrations from 1 to 400 mg/kg (Al, Ba, Cr, Fe, Mn, Rb, Sr, and Zn); and±8.31% for the ultra trace elements (<1 mg/kg) (Co, Cs, Eu, La, Sb, Sc, Se, Th, and V).  相似文献   

7.
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   

8.
The determination of trace elements in the various stages of the water cycle is very important. Economic procedures for multi-element determinations of trace elements in various matrices are needed. The applications of total-reflection x-ray fluorescence spectrometry in this general area are reviewed briefly, with examples relating to rain, river and sea waters, sediments, particulate matter and manganese nodules and crusts, as well as mussel tissue. Up to 25 elements can be determined; these are S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Pb, Se, Rb, Sr, Y, Zr, Mo, Ag, Cd, Sb and Ba. Preliminary treatments of the various matrices are described. Accuracy checks by analysis of reference standards and by application of independent techniques are reported.  相似文献   

9.
In order to evaluate alternative analytical methodologies to study the geographical origin of ciders, both multi-elemental analysis and Sr isotope abundance ratios in combination with multivariate statistical analysis were estimated in 67 samples from England, Switzerland, France and two Spanish regions (Asturias and the Basque Country). A methodology for the precise and accurate determination of the 87Sr/86Sr isotope abundance ratio in ciders by multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) was developed. Major elements (Na, K, Ca and Mg) were measured by ICP-AES and minor and trace elements (Li, Be, B, Al, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Mo, Cd, Sn, Sb, Cs, Ba, La, Ce, W, Tl, Pb, Bi, Th and U) were measured by ICP-MS using a collision cell instrument operated in multitune mode. An analysis of variance (ANOVA test) indicated that group means for B, Cr, Fe, Ni, Cu, Se, Cd, Cs, Ce, W, Pb, Bi and U did not show any significant differences at the 95% confidence level, so these elements were rejected for further statistical analysis. Another group of elements (Li, Be, Sc, Co, Ga, Y, Sn, Sb, La, Tl, Th) was removed from the data set because concentrations were close to the limits of detection for many samples. Therefore, the remaining elements (Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba) together with 87Sr/86Sr isotope abundance ratio were considered for principal component analysis (PCA) and linear discriminant analysis (LDA). Finally, LDA was able to classify correctly 100% of cider samples coming from different Spanish regions, France, England and Switzerland when considering Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba and 87Sr/86Sr isotope abundance ratio as original variables.  相似文献   

10.
The concentration of 14 elements in cigarette wrapping papers used in manufacturing 21 different Mexican cigarette brands was measured using instrumental thermal neutron activation analysis. These elements are As, Ba, Ce, Co, Cr, Cs, Fe, K, Na, Rb, Sb, Sc, Sr, Th and Zn. The concentration of the elements was compared with the reported concentration in similar studies for elemental content in Pakistani, American, Chinese, Egyptian, Jordanian and Iranian cigarette wrapping papers.  相似文献   

11.
The multitracer technique was applied to elucidate of influence of humate formation on adsorption behavior of ultratrace elements. Dissolved fractions of Co, As, Rb, Sr, Y, Zr, Ba, Ce, Eu, Gd, Tb, Yb, Lu, Hf, Re and Pt in contact with kaolinite or silica gel were determined simultaneously either in the presence or absence of humic acid, which was partly adsorbed on the solid. Percentage of dissolved fraction of rare earth elements was identical to that of humic acid, indicating high stability of the rare earth-humate complex. Hydrolysis was the most important factor controlling the behavior of Zr and Hf. Both hydrolysis and humate complexation influenced the adsorption of Co, Sr, Ba and Pt, whereas neither affected the distribution of As, Rb and Re.  相似文献   

12.
A systematic comparison of thermal and epithermal irradiations in the instrumental activation analysis of coal and fly ash was made. From a total of 44 elements, the epithermal irradiation technique appeared advantageous in 20 cases, namely Ni, Ga, As, Se, Br, Rb, Sr, Zr, Mo, In, Sb, Cs, Ba, Sm, Ho, Hf, Ta, W, Th and U. Data are presented for the National Bureau of Standards’ coal (SRM 1632) and fly ash (SRM 1633).  相似文献   

13.
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   

14.
The concentration of 28 elements in tobacco and cigarette paper in an Egyptian Cigarette were determined using instrumental neutron activation analysis. These elements are: Al, As, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, K, La, Mg, Mn, Na, Ni, Rb, Sb, Sc, Se, Sr, Th, Ti, V and Zn. The cigarette filter (before and after normal smoking) and the produced ash were analyzed to determine the adsorption of the elements on the filter and their remains in ash. The material balance for the determined elements were calculated.  相似文献   

15.
贺茂勇  逯海  金章东  王军 《分析化学》2012,(7):1109-1113
采用锶特效树脂(Sr-Spec)建立了快速分离富集人牙齿中微量元素锶,并测定87Sr/86Sr的有效方法。采用HNO3-HClO4体系消解牙齿样品,以8mol/L HNO3为介质上柱,8mol/L HNO3淋洗,0.05mol/LHNO3洗脱,收集淋洗液,蒸干;采用正热电离质谱法进行87Sr/86Sr的测定。结果表明,利用Sr-Spec树脂,不仅能将锶与基质中大量钙分离,并能有效分离同位素测定中干扰元素铷。本方法可以缩短分离时间,提高分离效率,减少试剂用量,降低实验空白。采用本方法对陕南地区人牙齿牙釉质中锶进行分离,测得的87Sr/86Sr值在0.710948~0.711037之间。  相似文献   

16.
A procedure for monostandard INAA of 21 elements (Hg, As, Br, Cr, Sb, Se, Ba, Zn, Ca, Ce, Co, Cs, Eu, Fe, Hf, K, La, Rb, Sc, Sr, Ta) in Chinese Biological Standard Reference Material (peach leaves) is described. The accuracy of the procedure was checked by analyzing the U.S. NBS Standard Reference Materials SRM-1571 and SRM-1632a.  相似文献   

17.
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   

18.
This paper presents elemental data of sediment samples and its analysis methodology. The samples were collected from Central Karakoram—an unexplored region in Pakistan. Surface sediment samples (0–10 cm) were collected from 9 different locations along the Hunza River in Central Karakorum at an average altitude of 1,561 m covering almost 100 km length along the river. Samples were analysed by the k 0-insturmental neutron activation analysis and the activation constant method for 34 elements (Al, As, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Ga, Hf, K, La, Mg, Mn, Na, Nd, Rb, Ru, Sb, Sc, Se, Sm, Sr, Ta, Tb, V, Yb, Zn, Zr, Th and U). The analysis methodology was discussed with important sources of nuclear and fission product interferences. The important components of uncertainties identified were the k 0-factor, Q 0-factor, detector efficiency and counting statistics. The methodology was validated by analyzing the IAEA-S-7 (soil) and IAEA-SL-1 (lake sediment) reference materials. The mass fraction data was explored by principal component analysis. Measured elemental mass fractions were compared with the similar data from other locations of the world. It was shown that anthropogenic activities have little influence on the elemental distribution in the sediment.  相似文献   

19.
ICP-MS法测定不同采收期山楂叶中微量元素   总被引:2,自引:1,他引:1  
建立了电感耦合等离子体质谱法(ICP-MS)测定不同采收期山楂叶中微量元素的半定量分析模式。结果表明,不同采收期山楂叶可测定的28种微量元素中,Mg、Si、K、Ca、Na、Al、Mn、Fe、Sr和Ba为主要元素。Zn、Rb、Sc、Li、Ge、In和Bi的含量随叶的生长逐渐下降,而Zr、Sn、Sb和Th与之相反,其它元素基本没有变化。该法简单、选择性强、灵敏度高、定量准确,适用于不同采收期山楂叶中微量元素测定,为全面控制山楂叶质量提供依据,也为合理开发和利用山楂叶提供借鉴。  相似文献   

20.
The first representatives of 4H (BaMnO3-type structure, P63/mmc, Z = 4) and 9R (BaMnO3-type structure, Rm, Z = 9) inverse Perovskite phases are presented. The phases are obtained within the solid solutions (Sr3-xBaxN)E with E = Bi, Sb. The crystal structures and homogeneity ranges were studied by combined X-ray and neutron diffraction as well as chemical analyses. The cubic Perovskite phase with Bi (Sb) is stable in the range of 0.00 < or = x < or = 0.90(5) (0.00 < or = x < or = 1.30(5)), the 4H variant is stable for 1.55(5) < or = x < or = 2.10(5) (1.85(5) < or = x < or = 2.45(5)), the 9R structure is stable for 2.50(2) < or = x < or = 2.55(2) (2.56(2) < or = x < or = 2.60(2)), and the 2H phase is stable for 2.75(5) < or = x < or = 3.00 (2.80(5) < or = x < or = 3.00). Ba occupies preferable sites in the hexagonal stacking of close packed layers of alkaline earth metal ions and E3-; Sr is mainly located in cubic stacked layers. The phase order upon going from cubic (Sr3N)E to 2H-type (Ba3N)E concomitant to the pronounced Sr/Ba partial order can, in general, be rationalized considering the Coulomb repulsion of nitride ions, as well as the size and charge density of the alkaline earth metal ions.  相似文献   

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