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1.
Instrumental neutron activation was used for the determination of 23 trace and minor elements in 4 different samples of brewer's yeast. Detection limits for these elements vary from 2 ppb to 100 ppm. The following average concentrations were found (ppm, dry weight): Al 597, Br 0.36, Cl 1473, Co 0.21, Cu 19, Fe 285, K 16 400, Mg 1355, Mn 8.4, Na 2330, Rb 19, Sb 0.053, Se 1.2, V 2.2 and Zn 80. NBS standard 1569 was also analyzed and the following concentrations (in ppm) were measured: Al 2300, Br 0.65, Ce 0.23, Cl 460, Co 0.26, Cr 2.12, Cu 11, Fe 707, Gd 7.1, Hf 0.13, K 15 500, Mg 1780, Mn 7, Na 510, Rb 16, Sb 0.075, Sc 0.18, Se 0.92, Th 3.7, Ti 38, U 0.49, V 4.1 and Zn 70.  相似文献   

2.
Twenty four male autopsies were obtained from Shanghai, China. The samples of liver, lung, kidney cortex, brain and scalp hair were collected from the autopsies. The elements As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Rb, S, Se and Zn were determined by neutron activation analysis (NAA). The present study shows the distribution of the elements in different tissues and provides the element level for normal persons in the local area. In general, the results are comparable with those of other countries.  相似文献   

3.
T Takeuchi  M Shinogi 《Radioisotopes》1979,28(12):729-733
Instrumental neutron activation analysis by the monostandard method has been applied to the analyses of biological NBS standard reference materials; 1571 Orchard Leaves and 1577 Bovine Liver. Aluminum foils containing 0.100% gold or 2.00% cobalt were used as the monostandards. The gamma-ray spectral data were recorded on punched paper tape and were analyzed by a computer assisted data processing. The following 25 elements were determined: Al, Ca, Cl Cu, Mg, Mn, V (by short period irradiation), As, Ba, Br, Co, Cr, Cs, Eu, Fe, Hg, K, La, Na, Rb, Sb, Sc, Se, Sm and Zn (by long period irradiation). The results were compared with the certified values by NBS and the reported values in literatures to prove the reliability and accuracy of the monostandard method.  相似文献   

4.
Fourteen elements can be rapidly determined in whole blood by the neutron activation analysis procedure described. Three of these (Ag, Cl, Se) are measured after a 10-s irradiation and eleven others (Al, Ba, Br, Ca, Cu, I, Mg, Mn, Mo, Rb, V) are determined by a 180-s irradiation of a 1-cm3 sample of whole blood after destruction of organic matter and removal of sodium by hydrated antimony pentoxide. A further 13 elements (As, Au, Co, Cr, Cs, Fe, Hg, K, Na, Ni, Sb, Sc, Zn) are determined after overnight irradiation in the SLOWPOKE reactor.  相似文献   

5.
Using instrumental neutron activation analysis (INAA), graphite furnace atomic absorption spectrometry (GFAAS), flame atomic absorption spectrometry (FAAS) and combustion elemental analysis, green coffees of the Arabica species produced in crop year 1987/88 in Colombia, Costa Rica, Cuba, El Salvador, Mexico, Nicaragua, Panamá and Papua New Guinea were analysed for the elements Ba, Br, C, Ca, Co, Cr, Cu, Cs, Fe, H, K, La, Mg, Mn, N, Na, Rb, Sc, Sr and Zn. In accordance with the concentrations determined, the elements could be ranked into five groups: Sc (sub-ppb level); Br, Co, Cr, Cs and La (ppb level); Ba, Cu, Fe, Mn, Na, Rb, Sr and Zn (ppm level); Ca and Mg (%o level); and C, H, K and N (% level). On the basis of the results obtained, an attempt was made to establish the origin of the green coffee via its elemental composition. Among the investigated elements, manganese was found to be best suited as an indicator for this purpose. However, the elements C, Co, Cs, Na and Rb proved to be of interest too.  相似文献   

6.
Instrumental neutron activation analysis (INAA) and proton induced X-ray emission (PIXE) analysis were used to determine the concentration of 13 elements in the breast milk collected within the first week of lactation and after morning feed from 16 pre-term mothers and 20 term mothers. The results of the study show that pre-term milk has a significantly higher concentration of Cl, Cu, Fe, K, Mg, Mn, Na and Zn while term mothers have a significantly higher concentration of P and Br. No significant differences were, however, found in the mean concentration of Al, Ca, I and Rb. Furthermore, the mean concentration for most of the elements found in the breast milk fall within the range of the concentrations obtained for the commercial infant milk formulae.  相似文献   

7.
The normal concentration levels of trace metals in several kinds of tissues of even-toed ungulates have been determined by instrumental neutron activation analysis, photon activation analysis, and flame atomic absorption spectrometry. In the present work the concentrations of 13 elements (Ag, Br, Ca, Co, Cu, Fe, Mg, Mn, Mo, Na, Rb, Se, and Zn) were analyzed.  相似文献   

8.
Forty two major, minor and some trace elements were determined by activation analysis in the new Czech Morávka H5 chondrite, which fell on May 6, 2000 in the vicinity of Morávka, north-east Moravia. The elements Na, Mg, Al, Si, Cl, Ca, Ti, V, Mn, Co, Ni, and Cu were determined by means of instrumental short-time neutron activation analysis (INAA), whereas another group of elements, namely Sc, Cr, Fe, Co, Ni, Zn, As, Se, Br, Sb, La, Sm, Ir, Au and Hg were assayed using long-time INAA. Most of the rare earth elements (REE) were determined by radiochemical neutron activation analysis (RNAA) using precipitation of their oxalates, whilst for the determination of Rb and Cs an RNAA procedure based on selective sorption of the elements on ammonium phosphomolybdenate was employed. Mg, Ca, Ti, Mn, Ni, Sr, Y and Zr were determined by instrumental photon neutron activation analysis (IPAA) using the irradiation with 20 MeV bremsstrahlung from a microtron. For quality control, the U.S. Geological Survey (USGS) reference rocks basalt BCR-1 and diabase W-1 were analyzed. Moreover, the self-verification principle in activation analysis was employed to increase the credibility of the obtained results.  相似文献   

9.
By the use of non-destructive neutron activation analysis (NAA) twenty-four trace (Ag, As, Br, Cd, Ce, Cr, Co, Cu, Eu, Fe, Hf, I, La, Mn, Ni, Rb, Sb, Sc, Se, Sm, Sr, U, V and Zn) and six minor (Ca, Cl, Mg, K, Na and S) elements were determined in a certified marine tissue standard reference material. Four non-destructive methods including thermal, epi-thermal, prompt-gamma ray and delayed neutron counting activation analyses were performed. Results when compared to the certified values showed the reliability of employing these methods in such standards program.  相似文献   

10.
Summary A study was conducted on erythrocytes in order to determine the composition and concentration of elements from patients undergoing coronary artery bypass grafting (CABG) surgery with and without type II diabetes. Samples were taken at various timeperiods and analyzed by means of proton induced X-ray emission (PIXE) analysis. Elements detected reliably were P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. In particular, elements worthy of note are S, Cl and Ca, which have strong implications in surgical procedures and aftercare.  相似文献   

11.
The elemental concentrations of Br, Ca, Ce, Cl, Co, Cr, Cs, F, Fe, Hf, K, Mg, Mn, Na, O, Rb, Sb, Sc, Se, V and Zn in 15 human lung autopsy samples, taken from subjects aged more than fifty years old, were determined by instrumental neutron activation analysis (INAA) using reactor neutrons in conjunction with a high resolution detection system. Two modes of irradiation and counting were applied; namely cyclic neutron activation analysis (CNAA) and conventional neutron activation analysis. Proton induced X-ray emission (PIXE) analysis, using a proton beam emerging from a 2 MV Van de Graff accelerator, was additionally employed and Ge, Ni, P and Ti were also identified in the lung tissue. Detection of the X-ray spectra was performed using a high resolution Si(Li) semiconductor. The relevance of these results, including a comparison between the concentrations of elements measured in a pig's lung using CNAA and those found in the human lung is discussed.  相似文献   

12.
Elemental profiles of brain tumor tissues from 15 patients of astrocytomas (grade I–III) and normal human brain tissues of 23 male age matched autopsies as controls have been studied by instrumental neutron activation analysis. The SLOWPOKE reactor with a thermal neutron flux of 8·1011n·cm–2·s–1 and swimming pool type reactor with a thermal neutron flux of 1·1013n·cm–2·s–1 were used for short and long irradiation of samples, respectively. Spectrophotometry was only used for analyzing phosphorus. A total of 18 elements Se, Na, K, Br, Cl, Mn, Mg, S, Ca, Cu, Hg, Cr, Fe, Rb, Zn, Co, Sc and P has been determined for this purpose. The reliability of methods has been checked by analyzing biological standard reference materials horse kidney (IAEA H-8) and bovine liver (NBS SRM 1577a). The analytical results showed that compared with the normal brain tissues, concentrations of Ca, Fe, Cu, Zn, Se, Mn, Br and Sc were significantly higher in tumor tissues (P<0.01) and concentrations of Rb, K and P were lower, while no differences for contents of Mg, S, Cr, Hg, Na and Cl were observed. A negative correlation between P and Ca in malignant and normal brain tissues was observed.  相似文献   

13.
Instrumental neutron activation analysis (INAA) based on a nuclear reactor and proton induced X-ray emission (PIXE) based on a 2 Me V Van de Graaff accelerator were used to analyse different environmental samples including coal, sawdust, fly ash and landfill materials. These samples represent a large component of the solid waste being buried in the ground, and may be a potential source of toxicity which can have not only adverse effects on the soil and ground water, if diffused during leaching processes, but may also be transferred to humans through the food chain. Both techniques were employed to determine trace element concentrations in these matrices. The concentration of 30 elements were detemined, namely Na, Mg. Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Cd, Ba, La, Sm, Eu, Tb, Ho, Yb, Hf, Ta and Th. The detection limits in the various sample matrices were calculated and a comparison was made for those elements commonly detected by both techniques.  相似文献   

14.
Summary Major and trace elements were determined in serum of patients with chronic myelogenous leukemia (CML) using total reflection X-ray fluorescence induced by synchrotron radiation (SRTXRF). CML affects 1 to 2 people per 100,000 and accounts for 7-20% cases of leukemia. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Br and Rb. Using analysis of variance (ANOVA) it was observed that the contents of the P, S, Ca, Cr, Mn, Fe, Cu and Rb elements differed significantly at a = 0.05 between groups of healthy subjects and CML patients and also genders (males and females).  相似文献   

15.
Trace elements in soft tissues of marine bivalves were determined by neutron activation analysis (NAA) and photon activation analysis (PAA). Elemental levels of Ag, As, Br, Co, Cu, Fe, I, Mn, Ni, Rb, Se, and Zn in the organs of giant ezoscallos, rock oysters, and giant crams were obtained. The metal-bound proteins were extracted from the mantles and hepatopancreases of rock oysters. By irradiating the fraction obtained by HPLC gel chromatography, we found the possibility for the existence of an Ag bound protein in the mantles.  相似文献   

16.
Forty brands of tobacco used in Indian cigarettes, 20 brands of bidis (tobacco rolled in wrapper leaves), 15 brands of chewing tobacco and 15 brands of snuff tobacco were analyzed by nuclear and allied techniques. The elements measured into tobacco can be grouped into seven categories from less than 1 ppm to 5% by weight. Concentration level varied from 0.5-5% for (Ca, K, Cl), 400-1500 ppm (Fe), 200-600 ppm (Na), 100-300 ppm (Ti, Mn, Br and Sr), 10-100 ppm (Cu, Zn and Rb), 1-10 ppm (Cr, Ni, Pb and La) and less than 1 ppm (As, Co, Cd, Sb, Hg and Eu). Among the above elements Cr, Ni, As, Cd, Pb, Hg and Sb are considered toxic. The percentage transfer of the elements from cigarette tobacco to smoke particles during smoking was also estimated using a smoking machine and collecting the smoke particles on a filter paper. The results show that Br, Cr, Sb and Zn have high percentage transfer from tobacco to its smoke of the order of 2-15%. Out of these Sb has the highest 15%. Cobalt, Fe and Sc have lowest percentage of transfer of the order of less than 1%. The percent transfer of these elements from tobacco to tobacco smoke is higher in case of bidis (1.5-3.0 times) as compared to cigarettes. In cigarettes also non-filter cigarettes have higher transfer (2-3 times) as compared to filter tip cigarettes.  相似文献   

17.
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   

18.
Four algae reference materials, IAEA-391, 392, 393 and IAEA-140, prepared by the International Atomic Energy Agency for intercomparison under different preparation conditions were analyzed for 24 elements. Conventional neutron activation analysis (NAA) was used to determine Al, Ca, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Sb, V and Zn and epithermal NAA using BN and Cd as shielding material for I, Br, As, Ni, Mo and Cd. Inductively coupled plasma mass spectrometry (ICP-MS) as a complementary and comparative method was applied to determine Pb, Sn, Ni, Sr, Rb, As, Co, Cr, Cu, Mn, V, Mo and Zn. Two analytical quality control standard reference materials IAEA-V-10 (hay powder) and IAEA-331 (spinach) were analyzed simultaneously with real samples. The results agree quite well with each other and with the certified values.  相似文献   

19.
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   

20.
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   

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