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1.
The purpose of this study was to evaluate the efficiency of superphosphate fertilizer in remediating a contaminated soil with potentially toxic elements. For this, different phosphorus doses were used in a number of lettuce plants. The element concentrations determined in their leaves were compared with those found in control lettuce plants. Instrumental neutron activation analysis was the analytical technique used to determine element concentration in lettuce leave samples. The application of 250 mg kg?1 of P was the most effective treatment to reduce the concentrations of Br, Ca, Cd, Cl, Co, Cr, Fe, K, Mg, Mn, Sb and Zn in lettuce leaves.  相似文献   

2.
Sixty-two heroin samples were analyzed for their contents of 15 trace elements (Au, Ba, Br, Ca, Ce, Co, Cr, Fe, La, Na, Sb, Sc, Sm, Th, and Zn) by neutron activation analysis (NAA). Large variations of elemental concentrations between samples were found to possess statistical significance. Of all the elements calcium was the most abundant element, followed by zinc and sodium. The concentrations of Au, Ce, Co, La, Sb, Sc, Sm, and Th in all the samples were below 1 mg·g−1. Classification of these heroin samples was achieved by the application of hierarchical cluster analysis. The results show that NAA can provide useful information on the origin of the illicit drugs. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

3.
In the under developed countries, the people of far-flung rural areas still depend to a large extent upon herbal medicines. At the foundation of usage of herbal medicine is the experience of thousands of years. The present paper deals with the characterisation of exotic fruits for essential and toxic elements. The samples include Morus nigra, Morus alba, Salvadora persica and Carissa opaca (from low and high altitude). Two standardizations of neutron activation analysis, that is, semi-absolute k 0-instrumental neutron activation analysis (k 0-INAA) and epithermal neutron activation analysis (ENAA) were employed for the quantification of elements. The analysis methodologies were validated by analyzing the IAEA-336 (lichen) and NIST-SRM-1572 (citrus leaves). Sixteen elements including Br, Ca, Cl, Co, Cr, Fe, I, K, Mg, Mn, Na, Rb, Sb, Sc Sr, and Zn were determined in all samples. Daily intakes of various elements from the samples were measured and compared with the dietary reference intakes. Additionally, principal component analysis was performed to extract information regarding samples and elements.  相似文献   

4.
Instrumental neutron activation analysis was applied for the determination of trace elements in Canoparmelia texana species collected mnonpolluted areas of Atlantic Forest and in six sites of Santo André Municipality, SP, Brazil. Concentrations of As, Ba, Br, Ca, Cd, Cl, Cr, Cs, Co, Fe, K, La, Mn, Na, Rb, Sb, Sc, Se, U, and Zn were determined and comparisons were made between the results obtained in lichens from different sites.  相似文献   

5.
k0-Based instrumental neutron activation analysis (k0 INAA) was used to determine the concentrations of Cr, Fe, Co, Zn, Se, Sb and Hg in the vascular plantsCistus salvifolius andInula viscosa and in the lichenParmelia sulcata. The samples were collected in the neighbourhood of industrial complexes. The elemental accumulation in the vascular plants and the lichen are compared to optimize the choice of the bioaccumulator. It is concluded thatP. sulcata seems to be the best accumulator of the three species for the elements studied;Cistus salvifolius is sensitive to the contents of Zn, Fe, Cr and Sb in the air;Inula viscosa seems to accumulate Fe, Sb, Co, Cr and Zn. Nevertheless, it is concluded that lichen is a good air pollution indicator, while the vascular plants are not due to the large seasonal variations found in the elemental concentrations.  相似文献   

6.
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   

7.
The epiphyte plant Tillandsia capillaris was used as a passive biomonitor to study the relationship between elemental accumulation and emission sources in the province of Córdoba, Argentina. The concentrations of As, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, K, La, Lu, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, U, Yb, and Zn were determined in T. capillaris leaves by Instrumental Neutron Activation Analysis. A variogram analysis was performed to identify the emission sources of these elements in the study area, obtaining different patterns for each element analysed. A principal-component analysis was subsequently performed to further confirm the different contaminant emission sources and it coincided with the results of the variogram analysis. We observed that the enrichment of most elements was associated with natural sources (soil) and that only some elements showed evidence of enrichement related to sources such as traffic (K, Sb and Zn), industries (Br), and mining activity (Ca).  相似文献   

8.
In Brazil, the use of herbal medicines is very popular due to its immense flora, cultural aspects and to the popular belief that herbs, which are of natural origin, are safe and without undesirable side effects. Aside from that public interest in natural therapies, the use of herbal medicines has increased expressively due to the high cost of synthetic medicines. In this study, elemental compositions of herbal medicines from the species Ginseng, Ginkgo biloba, Centella asiatica, Mulberry and Aloe vera supplied by different suppliers were evaluated by neutron activation analysis. The concentrations of As, Ba, Br, Ca, Cl, Co, Cr, Cs, Fe, Hf, K, Mg, Mn, Na, Rb, Sb, Sc, Th, Zn and some lanthanides were determined in these samples. Comparisons made between the results indicated differences in their elemental contents depending on the plant species, origins of the samples and the age of the leaves. The results also showed that the herbal medicines contain elements such as Ca, Co, K, Fe, Mg and Zn known as essential to humans and for treatment and prevention of diseases. Toxic elements such as Hg, Cd and Cu were not detected. Elements As and Sb were detected in some samples but at very low concentrations at the μg kg−1 levels. Herbal medicine results were also compared to literature values. Biological certified reference material was analyzed for quality control of the analytical results.  相似文献   

9.
《Analytical letters》2012,45(14):1233-1248
Abstract

An instrumental neutron activation analysis with Ge(Li) γ -spectrometry and computer-assisted data reduction, has been developed for the determination of more than 20 elements in different liquid fuels. Organo-metallic standard solutions were mixed to obtain suitable standards. Two neutron irradiations and 4 γ-spectrometric measurements are required for each sample. Corrections were taken into account for a few spectrometric and nuclear interferences. The overall standard deviation for nearly all elements is mainly determined by counting statistics. The following elements can be determined : Na, Al, S, Cl, K, Sc, V, Cr, Fe, Co, Ni, Cu, Zn, As, Se, Br and La whereas the concentration of the following elements are mostly near the limit of detection: Mg, Mo, Sb, Ba, Th and Hg.  相似文献   

10.
Some essential elements in eleven plant medicines used at the Center for Scientific Research into Plant Medicine (CSRPM), Mampong-Akwapim, Ghana, for the management and cure of various diseases were determined by instrumental neutron activation analysis (INAA), using thermal neutrons at a flux of 5.1011 n.s-1.cm-2. The plant medicines were: Sirappac powder-E, Tina-A powder, Blighia powder, Aphrodisiac powder, Ninga powder and Lippia tea. The others are Olax powder, Ritchiea powder, Momordica powder, Kenken and Fefe powder. Concentrations of seventeen elements namely Al, Br, Ca, Cl, Co, Cu, Cr, K, Mn, Mg, Na, Rb, Sb, Sc, Ta, V, and Zn have been determined by short, medium and long irradiation times. Of these elements Co, Sb, and Sc are found to be present at the trace level, Br, Cu, Cr, Mn, Rb, Ta, V and Zn at the minor level, while Al, Ca, Cl, K, Mg and Na were generally at major level. The differences in the concentration of the elements are attributed mainly to soil composition and climate in which the plants grow. Standard reference material NIST SRM-1571 (Orchard Leaf) was analyzed simultaneously with the samples. The precision and accuracy of the method were evaluated using real samples and the standard reference material. It was found that the elemental concentrations measured in the NIST SRM-1571 were within ±10% of the reported values. The importance of these elements as related to human health and nutrition has been discussed.  相似文献   

11.
The atmospheric pollution of São Paulo city is a serious problem due to the expansion of industrial area, increasing number of vehicles and population density. This work presents results obtained in the analysis of lichens collected in different sites of São Paulo city and in non-polluted areas of Atlantic Forest. Concentrations of twenty elements were determined in Canoparmelia texana species and comparisons were made between the results obtained in lichens from different sites. High concentrations of the elements As, Ba, Cd, Co, Cr, Fe, La, Mn, Sb and Zn were found for samples collected in sites located near industries and petrochemical plant. Br and Sb concentrations were also high in lichens from sites affected by vehicular emissions.  相似文献   

12.
Tobacco smoking/chewing has been a cause of concern because of it being related with oral cancer. It causes stimulation and ill physiological effects. Ten different brands of spit tobacco, eight gutkaas and five paan masalas have been analyzed for seven minor (Al, Na, K, Ca, Cl, Mg, and P) and 17 trace (As, Ba, Br, Co, Cr, Cs, Cu, Eu, Fe, Hg, La, Mn, Rb, Sb, Sc, Th, and Zn) elements by instrumental neutron activation analysis. Also Ni and Pb were determined by atomic absorption spectrophotometry. Concentration of Cd was below detection limit (<10?mg?kg?1) in the tobacco samples. Mg, generally added as MgCO3 to prevent caking, is present as minor constituent in spit tobacco and gutkaas but is below detection limit (<1?g?kg?1) in paan masalas. Most elemental concentrations vary in a wide range depending on the nature of chewing tobacco. Spit tobacco has been found to be more enriched in essential elements (Ca, K, Na, P, Mn, and Rb), whereas gutkaas contain higher concentrations of Fe, Cr, Cu, and Zn. Paan masalas contain lower contents of other elements but higher content of Hg. Gutkaas also contain higher amounts of As and Pb. Further glutamic acid has been separated from tobacco leaves and characterized as it might bind with some elements.  相似文献   

13.
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   

14.
Neutron activation analysis (INAA) has been applied to multielemental determination of eleven medicinal plants used to cure the urinary tract diseases observed in Algeria. These plants include Androgena Citratus, Ceratonia Siliquata, Punica Granatum, Glyryrrhiza Glabra, Lausaunia Alba, Fragaria Vesca, Arbutus Unedol, Hordeum Vulgaris, Papieteria Officinalis, Zea Mays L, and Davallia Seae. Concentrations of twenty elements Ba, Br, Ca, Cl, Co, Cu, Cr, Fe, I, Mn, Na, Mg, Rb, Sb, Se, Sc, Sr, Ti, V, and Zn have been determined by short, and long irradiation times with a thermal and epithermal flux of 1.4·1012 n·cm−2·s−1 and 1.4·1011 n·cm−2·s−1, respectively. These analyses were performed in conjunction with Compton suppression. In almost herbs studied the Co, Cr, Cu, Rb, Sb, Sc, Se and V are found to be present at trace levels, Br, Mn, and Zn at the minor level, and Ca, Cl, Fe, Mg and Na are generally at the major level. The accuracy of the measurements has been evaluated by analyzing NIST-botanical references materials.  相似文献   

15.
Thermal neutron activation analysis and a large-volume high-resolution Ge(Li) gammaray spectrometer, connected on-line to a DEC PDP 8/L computer, have been used to measure the concentrations of Na, Sc, Cr, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, W and Hg in some Italian subsurface water samples. The instrumental method requires neither a chemical separation technique nor a pre- or post-concentration of the trace elements to be detected. As a consequence, this method eliminates many inherent errors associated with chemical determinations. The technique is sensitive, precise and particularly suitable for routine analysis of many trace elements at both natural and pollution levels in water samples. The interferences due to fast neutron (n, p) and (n, α) reactions are not appreciable, with the only exception of the54Fe(n, p)54Mn and58Ni(n, p)58Co reactions. Losses of volatile, elements, e. g. As, Br and Hg, during irradiation proved to be negligible.  相似文献   

16.
Abstract

We assessed the relationship between V, Cr, Mn, Hg, As, Cd, Sn, Sb and Pb concentrations in Mytilus galloprovincialis samples from the coasts of Sicily and the expression of metallothioneins. Toxic mineral elements assessment was carried out by A.A. Spectrometry and ICP-MS. The metallothioneins expression was performed by q-PCR method. Low metals’ levels were found in the mussel samples examined, in comparison with what was reported in literature. The highest mean values of toxic mineral elements were found in Gela (Cr 0.178?±?0.03?mg/Kg, Mn 4.325?±?0.012?mg/Kg, As 3.706?±?0.009?mg/Kg, Sn 0.148?±?0.014?mg/Kg, Sb 0.009?±?0.004?mg/Kg e Pb 0.364?±?0.01?mg/Kg). Significant levels of Hg were found in samples from Catania (0.014?±?0.005?mg/Kg). Only vanadium and lead concentrations showed significant differences between sampling areas (p?<?0.05). Molecular analysis verified a basal expression of Mt1 and the absence of over-expression of Mt2, confirming the low mineral’s concentrations found in the samples examined.  相似文献   

17.
A method has been developed for the determination of elements in normal and diseased tissues of the bone employing radiochemical and instrumental neutron activation analysis. Elements such as Na, Br, Au, Sb, Sc, Fe, Zn and Cr were subjected to irradiation in 252Cf or CIRUS reactor followed by measurement of the activity on a HPGe detector coupled to a PC based MCA unit. Elements such as Co, Ca and P were subjected to radiochemical separation prior to the measurement. The statistical evaluation with respect to accuracy and precision is discussed.  相似文献   

18.
Instrumental neutron activation analysis was used to determine elemental contents of Elephas primigenius mammoth mandible bone and Pecten solarium shell fossils discovered in Romania during 1995–1996. In addition, calcareous sedimentary rock surrounding the shell fossil was analyzed. Concentrations of Al, As, Au, Ba, Br, Ca, Co, Cr, Cs, Fe, Hf, K, Mg, Mn, Na, Ni, Rb, Sb, Sc, Se, Sr, Th, U, V, Zn and the rare earth elements Ce, Eu, La, Lu, Nd, Sm, Tb, Yb were determined. The results are discussed and compared to the available data in the literature for similar fossils.  相似文献   

19.

The application of preconcentration by dry-ashing to the neutron activation analysis of biological samples using a SLOWPOKE-2 low-power reactor is reported. Samples of selected food crops (banana, callaloo, carrot, mango, and yam) and bioindicator plants (lichen, moss, Tillandsia sp., and tree bark) were analysed both as plant tissue, and as ashed sample. The results are presented for 21 elements. Good agreement between both procedures (<10% relative standard error) was obtained for 13 elements: Al, Ca, Cd, Cr, Fe, K, La, Mg, Mn, Na, Sm, Ti, and V. For Dy, Rb, and Zn the agreement was 10-15%. Relatively poorer agreement (>15-30%) was obtained for As, Br, Cl, and Sb. Dry ashing produced improved analytical results for those samples that were of low ash content. However, the increased background counts observed in ashed samples can sometimes negate the concentration gain, particularly in plants with high ash contents but low levels of certain elements.  相似文献   

20.
Plastic products may contain high levels of trace elements, which, upon final incineration, may affect the environment. In the case of packing material, may affect food quality. In this work, instrumental neutron activation analysis was applied to the determination of As, Ba, Br, Cd, Co, Cr, Fe, Sb, Sc, Se, Ti and Zn in plastic materials originated from household and hospital wastes. Toxic elements such as Cd and Sb were found at the levels of mg·kg–1 in some food containers and also high levels of Ti were found in opaque packages. The accuracy and the precision of results were also evaluated by interlaboratory comparison.  相似文献   

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