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1.
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   

2.
A systematic study was undertaken in order to find out which of the most relevant elements can be determined in water under normal conditions by non-destructive neutron activation simultaneously using a suitable monostandard method. Standardized water samples as well as natural water of different kind were used, brought to dryness by freeze-drying and irradiated in quartz at a neutron flux of 1014 cm−2 s−1 for 1 day. The trace element content in quartz ampoules of different origin was determined separately. The following elements are discussed in detail including possible interferences: As, Au, Br, Ca, Cd, Co, Cr, Cu, Eu, Fe, Hg, K, La, Mo, Na, Ni, Sb, Sc, Se, U, Zn. Presented at the Euroanalysis II Conference, Budapest, 25–30. Aug. 1975.  相似文献   

3.
Instrumental neutron activation analysis (INAA) and Ge(Li) spectrometry have been used to determine Sc, Cr, Fe, Co, Ni, Zn, As, Se, Sb, Eu, Au, Hg, and U in crude petroleum. The technique involves no chemical separations and no pre-concentration of the samples by ashing is necessary, thus avoiding contamination or loss of volatile elements. The estimated detection limits in ppb for the elements are Sc (0.1), Cr (0.16), Fe (400.0), Co (0.6), Ni (1.1), Zn (200.0), As (6.0), Se (23.0), Sb (1.0), Eu (0.58), Au (0.11), Hg (4.3), U (1.5). Precision values ranged from 0.1% to 15% (relative standard deviation). Interferences in the Co and Fe determinations due to fast neutron reactions (n, p) and (n, α) on Ni isotopes are small and are easily corrected. Losses of As, Se, and Hg due to escape of volatile gases during irradiation are negligible  相似文献   

4.
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   

5.
Wheat is one of the most grown crops in Saudi Arabia. It is grown in various regions of the country. Accurate knowledge of the elemental concentrations in wheat and its products (bran and flour) is of great importance from a nutritional point of view. Wheat samples were obtained from the Al-Qusim region, 300 km northwest of Riyadh, and analyzed. Up to 50 elements (Al, Sb, As, Ba, Br, Cd, Ca, Cs, Cl, Cr, Co, Cu, Ga, Au, Hf, In, I, Ir, Fe, Mg, Mn, Hg, Mo, Ni, K, Rb, Sc, Se, Ag, Na, Sr, Ta, Te, Th, Sn, Ti, W, U, V, Zn, Zr, Ce, Dy, Eu, La, Lu, Nd, Sm, Tb and Yb) were determined in the wheat products. It was observed that the elemental content of bran was much higher than that of white flour.  相似文献   

6.
Résumé On décrit la détermination de traces dans le germanium, le silicium et le sélénium. En appliquant des techniques gamma spectrométriques, précédées ou non de séparations chimiques il est possible de doser les éléments suivants dans (1) germanium: As, Cu, Au, Ga, Zn, Hg, Cr, Sn, Sb, Co, In, Ni, Ir, Se, Sc, Ag, Ta, Hf et U; (2) silicium: P, Au, Sb, Ga, Fe, K, Cr, Mo, Sn, As, Co, In, Zn, Cu, W, Ta, Na, Eu, Sm, La, Sc et T1; (3) sélénium: Cl, Br, I, P, S, Te, Na, K, Cr, Fe, Co, Cu, Zn, Ga, Sc, Ag, Cd, La, W, Au et Tl. Les concentrations et ou limites de détections varient de quelques parties par million à 10−3 parties par milliard.  相似文献   

7.
The application of multielement standards (MES) in routine neutron activation analysis brings a whole range of advantages. This paper deals with the experience obtained during many years of application of these MES. Nine of these MES contain a total of 50 elements in suitable combinations and concentrations; thus, the determination of most of the common elements by NAA can be carried out simultaneously. This refers to the following elements: Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Mo, Ag, Cd, In, Sb, Te, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, W, Re, Au, Hg, Th and U. For the determination of the remaining elements such as Zr, Ta, Ir etc., single element standards (SES) are used.  相似文献   

8.
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   

9.
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   

10.
The possibilities of trace element adsorption on different adsorbents are investigated. Three procedures are described' (a) adsorption on activated charcoal at pH 8.5, (b) adsorption on activated charcoal in presence of dithizone at pH 8.5 and (c) adsorption on activated charcoal in presence of sodium diethyldithiocarbaminate at pH 5.5. Of the 23 elements which have been investigated in detail using standardised samples of water the following are determined quantitatively within an error of 10% according to procedure (a) and (b) Au, Cr, Eu, Hg, La, Sc, U and Zn, according to procedure (b) also Cd. The elements Ag, As, Ce, Fe and Se are adsorbed according to procedure (a) and (b) with yields between 60 and 90%, according to procedure (b) also Co. Mo is adsorbed by procedure (c) quantitatively. Cu is not detected after a decay time of 3 days. Sb is adsorbed by all procedures with low yields between 18 and 56%. The elements Br, Ca, Cl, K and Na remain mainly in the solution. The decontamination factors for these elements range between 102 and 106 (Na). Water from the North Sea is analysed by procedure (b).   相似文献   

11.
The trace-element composition of crude oil was studied using instrumental neutron activation techniques and a large-volume high-resolution Ge(Li) detector. A total of 29 elements were determined in oils representing the various producing formations of the Iraqi oil fields. These were: Al, Ar, As, Au, Br, Ca, Cl, Co, Cr, Cu, Eu, Fe, Ga, Hg, K, La, Mn, Mo, Na, Ni, Re, S, Sb, Sc, Se, Sm, V, W and Zn. The significance of these trace elements in the geochemical investigation of crude oil is discussed.  相似文献   

12.
The variation with age of the mass fraction of 54 trace elements (Ag, Al, As, Au, B, Be, Bi, Br, Cd, Ce, Co, Cr, Cs, Dy, Er, Eu, Fe, Ga, Gd, Hf, Hg, Ho, Ir, La, Li, Lu, Mn, Mo, Nb, Nd, Ni, Pb, Pd, Pr, Pt, Rb, Re, Sb, Sc, Se, Sm, Sn, Ta, Tb, Te, Th, Ti, Tl, Tm, U, Y, Yb, Zn, and Zr) in intact nonhyperplastic prostate of 65 healthy 21–87 year old males was investigated by instrumental neutron activation analysis with high resolution spectrometry of long-lived radionuclides and inductively coupled plasma mass spectrometry. This work revealed that there is a significant tendency for an increase in Bi, Cd, Co, Fe, Hg, Sc, Sn, Th, U, and Zn (p < 0.0014) mass fraction in normal prostate from age 21 years to the sixth decade. In the sixth to ninth decades the mass fractions of almost all chemical elements investigated in nonhyperplastic prostates were maintained at approximately stable levels. Our finding of correlation between pairs of prostatic chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element relationships with increasing age.  相似文献   

13.
Nigerian soda samples have been analyzed for major, minor and trace elements using instrumental neutron activation analysis. The following elements were determined; Na, Sm, U, La, Cr, Eu, Zn, Hf, Fe, Sc, Ba, Rb, Cs, Co, Au, Yb, Lu, Th, Ce, Zr, Se, As and Ta. The samples appear safe to use in human diet, although they may still require industrial purification to bring down the level of nonessential elements and those that could be toxic when present at high concentration.  相似文献   

14.
Instrumental neutron activation analysis /INAA/ method was applied to measure major, minor and trace elements in 34 samples of hard and brown coal originating from eight Polish coal mines. The elemental concentrations of 38 elements /Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Mo, Ag, Cd, In, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Lu, W, Au and Th/ are presented and compared with published data for coals from various origin. Enrichment factors, calculated relative to iron and the average crustal rock composition, indicated that several elements are highly enriched in Polish coals.  相似文献   

15.
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   

16.
The developed strategy permits determination in three steps of sixty-seven elements using inductively coupled plasma mass spectrometry (ICP-MS). Sodium, Mg, Si, S, Cl, K, and Ca are determined in a first step; B, Al, P, Cr, Fe, Mn, Ni, Cu, Zn, As, Se, Ag, Cd, Sb, Ba, Hg, and Pb are determined in a second step; and Li, Be, Ti, V, Co, Ga, Ge, Br, Rb, Sr, Y, Zr, Nb, Mo, Sn, Te, I, Cs, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Pt, Au, Tl, Bi, Th, and U are analyzed in a third step. The figures of merit obtained are adequate to carry out water quality monitoring and other hydrochemical studies, such those based in the application of hydrochemical fingerprinting to water management.  相似文献   

17.
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   

18.
A scheme for INAA of 32 elements (As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, Ir, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, U, W. Yb, Zn) in quartz glass is proposed. The accuracy of the procedure is evaluated by the analysis of two NBS standard reference materials (SRM-1571 and SRM-1632-a). The method is convenient for routine work. The method was used for the determination of impurities in laboratory quartz glass. Dedicated to the 60th birthday of acad. prof. g. bliznakov  相似文献   

19.
Non-destructive neutron activation analysis, employing a high-resolution Ge(Li) detector, was applied to determine the concentration of 24 trace elements in the tobacco of the Zarrin cigarette which is commercially made in Iran. 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. The smokes from the combustion of this tobacco and of the cigarette paper were also analysed for these elements and the percentage transference values were calculated.  相似文献   

20.
Fifteen elements at trace levels have been determined by neutron activation analysis in the biological standard kale distributed byBowen. La, Br, As, Se, Sc, Ag, Zn, Co, Cr, Sb, Eu, Fe, and Zr have been determined by a nondestructive technique using a high-resolution Ge(Li) detector. Two more elements, Au and Hg, have been determined after radiochemical separation. The nondestructive procedure is shown to yield data in generally good agreement with those obtained by destructive techniques. Potential sources of error in the nondestructive technique are discussed.  相似文献   

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