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1.
The concentration of 15 elements in various brands of cigarette tobacco and cigarette wrapping paper were determined using instrumental neutron activation analysis. The paper of some of the brands contains higher concentrations of toxic elements than the tobacco. The cigarette filter and the ash were also analyzed to determine the adsorption of toxic elements on the filter and their transference in smoke. The toxic effects of some of the elements have been briefly discussed.  相似文献   

2.
Instrumental neutron activation analysis has been applied in the determination of toxic and other trace elements in a set of three algae materials provided by the International Atomic Energy Agency, with the aim of environmental preservation through enhanced applications of nuclear analytical techniques. The quality of the analysis method has been evaluated by analyzing a number of biological standard reference materials. By adding mineral nutrients, the cultivation of algae for metals is enhanced, in particular, selected toxic heavy metals such as As, Cd, Cr, Hg, Ni and Pb. It is believed that the level of elemental concentration in algae samples are dependent on environmental conditions due to its biochemical properties. Therefore, algae materials may be useful as an indicator or controller of environmental water pollution.  相似文献   

3.
The concentration of certain toxic and essential elements in various brands of tea consumed locally were determined using instrumental neutron activation analysis. Transference of these elements into the drinkable portion was studied by brewing and boiling tea leaves for two minutes and the approximate intake was calculated from this data. The toxic effects of Hg, Se, As, Br and Sb are briefly discussed.  相似文献   

4.
INAA and anti-Compton spectrometry has been employed in the analysis of test bone samples. Validity and accuracy of the method were checked by the use of two biological reference materials procured from the National Institute of Standards and Technology, USA (NIST) and the International Atomic Energy Agency, Austria (IAEA). NIST 1486 Bone Meal (ca. 200–800 mg) and A-11 Milk Powder (ca. 200–600 mg) samples were irradiated in the 100 kW TRIGA Mainz reactor. Concentrations of 13 elements in both biological reference materials have been determined and were found in good agreement with the certified and provisional values.  相似文献   

5.
The lanthanides (REE) in 142 fern leaves collected from several sampling sites in Japan have been determined by neutron activation analysis, and the correlations between any two REEs in the logarithmic scattering diagram were examined. The relationship was expressed by the general formula, Y=aX+b with a correlation coefficient R. A strong positive correlation was seen between any two REEs in the diagram with a regression coefficient and a correlation coefficient close to unity. However, between Eu or Tb and other REEs the relationship was split into two lines with the same correlation coefficient. From the intercept b, the relative abundance of the two elements was determined for each REE and compared with those in hickory and tobacco leaves. These findings indicated that the abundance pattern of fern leaves is quite different from those of hickory and tobacco leaves. Namely, the relative abundance of La and Ce was quite similar in the three plants, but the abundance of the other REEs (Nd, Sm, Gd, Dy and Lu) was considerably lower in ferns than in hickory and tobacco leaves. For Eu and Tb the higher values obtained in fern leaves coincided with those of the two plants.  相似文献   

6.
This paper shows the result of soil-plant relation in samples from Cuban sugar canes of different soil types and cane varieties, using INAA from a thermal reactor. The behavior of minor and trace elements in sugar cane leaves is unifor and independent of sugar cane variety of type of soil. The soil-plant relation shows four principal groups of micro elements, according to their absorption by the plant.  相似文献   

7.
Instrumental neutron activation analysis was carried out to obtain the normal concentration of trace elements in bovine tissues (heart, liver, kidney, spleen, lymph nodes) and serum. Concentrations of 17 elements were determined. In this paper, concentrations of Al, Br, Cs, In and Rb are given and correlations of concentrations are discussed between Cl and Br and between K and Cs or Rb. Significant positive correlations have been found between Cl and Br concentrations in all tissues, between K and Cs concentrations in tissues excluding kidney, and between K and Rb concentrations in tissues excluding liver.  相似文献   

8.
The aim of this study is to evaluate the sensitivity of Ko-method of Instrumental Neutron Activation Analysis for minor, trace and toxic elements in the most consumed foodstuff purchased from large commercial markets in Kenitra’s city (Morocco) which has been chosen for a pilot project on food monitoring in the west of Morocco. Samples have been analyzed by Ko-INAA method using TRIGA Mark II reactor at Josef Stefan Institute in Slovenia. The quality control of results was assessed using the Standard Reference Material SRM 1547 (Peach leaves). Results show an adequate sensitivity for the most studied elements in foodstuffs except for beef, onion and whole wheat which show a high sensitivity factor for Cd and As. INAA seems to be an adequate choice for element analysis in foodstuffs.  相似文献   

9.
10.
Instrumental neutron activation analysis, INAA, was utilized for the determination of Al, Au, Br, Ca, Cl, Co, Cr, Cu, Fe, I, K, Mg, Mn, Na, Rb, Sc, V and W in 12 Tilapia Nilotica samples collected from the Aswan High Dam Lake following the destructive techniques.  相似文献   

11.
A systematic non-destructive determination of eighteen trace elements (F, Na, Cl, Sc, Mn, Zn, Br, Sr, I, Ba, La, Ce, Sm, Eu, Tb, Yb, Th and U) in carbonate samples by thermal neutron activation analysis was developed. Three 0.2–0.5g samples were irradiated for 15 sec (in the case of determination of F), for 3 min (in the case of Na, Cl, Mn, Sr and I) and for 60 hrs (in the case of Sc, Zn, Br, Ba, La, Ce, Sm, Eu, Tb, Yb, Th and U) in the TRIGA MARK II Reactor at a thermal neutron flux of 5·1011 n·cm−2·sec−1 (15 sec and 3 min irradiation) and 1.5·1012n·cm−2·sec−1 (60 hrs irradiation), respectively. According to the half life of the nuclides formed, the activities were measured with a Ge(Li) spectrometer as follows,20F∶15 sec counting after 20–25 sec cooling,24Na,38Cl,56Mn,87mSr and128I∶600 sec couting after 30–120 min cooling,82Br,140La,153Sm,175Yb and239Np (daughter of239U)∶3000 sec counting after 1 week cooling,46Sc,65Zn,131Ba,141Ce,152Eu,160Tb and233Pa (daughter of233Th)∶5000 sec counting after 1 month cooling. The errors due to the fluctuation of the neutron flux and the counting geometry were minimized by the use of calcium determined previously with EDTA-titration as an internal standard. The interferences from24Mg(n, p)24Na and235U(n, fission) reactions were corrected by the activities produced by the reactions in unit weight of magnesium and uranium, and their concentrations in samples measured experimentally. The data of Na, Mn, Zn and Sr were compared with the results obtained by atomic absorption analysis.  相似文献   

12.
An instrumental neutron activation analysis method based on the measurement of239Np has been developed for the determination of uranium in ores. The samples after 5 sec irradiation were cooled for 3 days and the gamma-ray spectra were measured with a 30 cm3 Ge(Li) detector. The precision and accuracy of the proposed method were determined by analysing IAEA Standard Uranium Ore samples.  相似文献   

13.
An instrumental neutron activation analysis (INAA) method has been developed for multi-element determination in geological samples. The INAA method consists of irradiation of samples for 90 sec at a flux of 1.0·1012 n·cm−2·sec−1 and determination of 12 elements by using their short-lived nuclides. Samples have been re-irradiated for 3 hrs for measuring concentrations of another 10 elements. Precision and accuracy of the INAA method have been evaluated by analysing samples and USGS standard reference materials. Precision and accuracy are within±15% and ±10%, respectively.  相似文献   

14.
The instrumental neutron activation analysis method was used for determination of 12 rare earth elements in red and white bauxites. Consideration was given to those systematic errors which in a relative method of analysis can result from the effects of neutron self-shielding, photon self-absorption and fission interfering reactions, due to different chemical composition of bauxite samples and the standard of silicate rock. Also presented is the characteristics “V” shaped chondrite normalized rare earth pattern of white bauxites.  相似文献   

15.
The trace elements content of Cola acuminata and three varieties of Cola nitida have been determined using neutron activation analysis. The samples have been irradiated at the Joint Universities Research Reactor, Risley, England for 71/2 hours in a neutron flux of 2.5·1012 n·cm–2s–1 and analysed using high resolution lithium drifted germanium detector coupled to a Canberra 35 microprocessor as a 4096 channel gamma spectrometer. The elements: Na, K, Br, W, Fe, Cs, Co, Zn, and Sc were detected.  相似文献   

16.
Multielement neutron activation analysis has been applied to the determination of macro, micro and trace amounts of Al, Br, Ca, Cl, Co, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sc and V in molasses of Kom Ombo, Edfu, Armant, Naga Hammady and Abu Korkass cane sugar factories. The threshold element concentrations are acceptable and below the safety. Differences in element concentrations may be related to different botanic textures and structures, different compositions of sugar cane plants, corrosion of containers or changes in soil as a result of geochemical differentiation. The method is sensitive down to 0.038 ppm of V. The relative errors due to counting statistics are in the range of 0.2–11%.  相似文献   

17.
The concentration of 12 trace elements in the chewing tobacco and two different brands of Libyan cigarette Atlas and Sport has been measured by instrumental neutron activation analysis and compared to the results of cigarette tobacco from India, USA, Iran and Yugoslavia. These elements are Co, Cr, Cu, Fe, Hf, Mn, Rb, Sc, Th, U, V and Zn.  相似文献   

18.
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   

19.
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   

20.
Researcher’s interest is increasing worldwide to study the role of trace elements in brain tissues. This paper discusses the application of k 0-instrumental neutron activation analysis to study the distribution of trace elements in seven different anatomical regions of goat brain. These regions include cerebellum, cerebrum, medulla oblongata, meninges, midbrain, pons and thalamus. The analysis protocol followed 1 h irradiation at 10 MW material testing type nuclear research reactor with nominal thermal neutron flux of 2 × 1013 cm?2 s?1. A total of 14 elements, namely Br, Co, Cr, Eu, Fe, Hg, K, Na, Rb, Sb, Sc, Se, Tb and Zn were determined in all parts. Reliability of the method was assessed by analyzing biological reference material IAEA-336 (lichen). On comparing the analytical results with the healthy human brain data, it showed that eight elements (Eu, K, Na, Rb, Sb, Sc, Se, Tb) were found with relatively higher elemental concentrations in human brain. Principal component analysis revealed distribution of seven parts in different three groups having similar elemental concentrations of elements.  相似文献   

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