共查询到20条相似文献,搜索用时 15 毫秒
1.
Hair samples of mildly mentally retarded (LR), moderately mentally retarded (MR), severely mentally retarded (SR) and normal children were collected and measured, using neutron activation analysis and X-ray fluorescence to determine the concentrations of Al, Sb, As, Ca, Cu, I, Fe, Pb, Mg, Mn, Hg, K, Sr, S, V and Zn. The groups of children were of ages between 5 and 13. Difference in the mean concentration of each element between groups was tested by Student"s t-test. No trend, either decreasing or increasing, has been established as the degree of severity increased from normal to SR children, except for the case of Cu. The present work may shed some light in the interpretation of findings on the effects of trace elements on neurobehavioral functions. 相似文献
2.
Li-Yun Jin G. Capannesi L. Renzi F. Sedda 《Journal of Radioanalytical and Nuclear Chemistry》1991,155(5):325-333
A study of trace elements in hair samples from two children of different sex on different sampling dates has been carried out using INAA. Using several combinations of irradiation, cooling and counting times, about thirty elements were quantitatively determined. Some conclusions could be drawn from the data obtained.Visiting scientist in ENEA C.R.E. Casaccia, Rome, Italy during 1989. 相似文献
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M. Saiki E. R. Alves O. Jaluul N. M. Sumita W. Jacob Filho 《Journal of Radioanalytical and Nuclear Chemistry》2008,276(1):53-57
Neutron activation analysis was applied to assess trace elements concentrations in head hair from healthy elderly people living in the São Paulo metropolitan area. Concentrations of As, Br, Ca, Cl, Co, Cr, Cu, Fe, K, La, Mn, Na, Sb, Se and, Zn were determined. Comparisons were made between the results obtained for dyed and non-dyed hair as well as for hair from females and males of two different age groups. The results were also compared with range values established by clinical laboratories and published data. 相似文献
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Scalp hair samples from 100 individual residents in Isfahan, Iran were analyzed for Al, Br, Ca, Cu, Hg, I, K, Mg, Mn, Na, S, V, and Zn by instrumental neutron activation analysis. The results of this investigation show that the ranges of the concentration of trace elements in hair are somewhat wide, for example Mg has the range of 20 to 209 ppm for 100 subjects. The results are compared with the data reported in the literatures. A substantive correspondence between the present data and literature values from different countries, have been observed but they did not show any regular dependence. The level of iodine is significantly different from other countries and is strongly linked to local environmental factors. The correlation coefficient for Al–V, Mn–Al, Ca–Mg, and V–Mg pairs was 0.823, 0.821, 0.830 and 0.746, respectively. 相似文献
7.
N. B. Ivanenko A. A. Ganeev N. D. Solovyev L. N. Moskvin 《Journal of Analytical Chemistry》2011,66(9):784-799
Main approaches to the trace element analysis of biological fluids and problems appearing in this case are considered. The specific character of these approaches is illustrated by the examples of the analysis of real samples for various trace elements. The advantage of methods for the direct determination of trace elements in these samples is demonstrated. 相似文献
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R. P. Meshcheryakov I. P. Chernov A. N. Oblivantsev B. I. Kuznetsov G. I. Tronov A. G. Rybasov 《Journal of Radioanalytical and Nuclear Chemistry》1973,16(2):427-438
A method is presented for determining the concentration of light elements in a surface layer up to 15 μm deep, utilizing the
anomalous increase in elastic scattering cross-sectional area when high-energy alpha-particles are scattered by light nuclei
through large angles. For the separation of the short-lived nuclide17F, isotope-exchange between the solid and liquid phases was applied. 相似文献
10.
Concentrations of up to 16 elements have been determined in subcellular fractions of bovine kidney using INAA methods. Levels of Rb and Se have been measured by a cyclic INAA method. A conventional INAA method consisting of 2 irradiations and 3 counting periods has been employed to determine the other elements. Accuracy of measurements has been evaluated by analyzing several standard reference materials. Trace element content of reagents used has been investigated in detail. Fresh samples of bovine kidney have been homogenized in a buffer containing sucrose and HEPES, and the homogeneate separated into nuclei, mitochondrial, lysosomal, microsomal and cytosol fractions by successive differential centrifugation. Concentrations of trace elements have been measured in these fractions using the INAA methods. 相似文献
11.
A microwave-assisted digestion procedure using HNO3, HF, and H2O2 has been developed for analysis of elements in ambient particulate matter (PM). The samples are collected on cellulose filters and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The ICP-MS is calibrated with external standards, and recovery of analytes is tested with NIST SRM 1648 Urban Dust. This method has been used to quantify the airborne concentrations of a large number of elements, including Ag, As, Ba, Be, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, K, Li, Mg, Mn, Mo, Ni, Pb, Rb, Se, Sb, Sr, Ti, Tl, V, and Zn. For the majority of these elements, recovery of the NIST SRM is within 15% of the certified values. 相似文献
12.
126 samples of scalp hair from inhabitants of Central Bohemia were searched for content of zinc, cobalt, cesium, chromium, scandium, selenium, and iron, for the purpose of medical research. Simultaneous determination of the elements was made by INAA. Inorganic standards were used for calculation of concentrations of elements. Quality assurance was checked by IAEA certified reference material and by internal standard mixed human serum. Statistical results are expressed in ppm, or ppb. Both normal and, if necessary, log-normal distributions of elements are presented, and types of distribution curves are verified statistically on 95% level of probability. 相似文献
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Lj. Jaćimović R. Drašković B. Ostojić 《Journal of Radioanalytical and Nuclear Chemistry》1977,37(1):415-419
The contents of Hg, Cr, La, Sc, Co, Fe and Sb in some human concretions have been determined by instrumental radioactivation
analysis. Urinary bladder and kidney concretions surgical removed from the patient have also been analyzed. 相似文献
15.
Micro and macro elements such as Zn, Cu, Mn, Fe, Co, Na, K, Ca and Li were detected from Rheum moorcroftianum Royle, a plant used in folk medicines. Altitudinal and seasonal variation of these trace elements in cultivated and wild roots and leaves of R. moorcroftianum were quantified by atomic absorption spectroscopy. The highest concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca and Li were found to be 376.0?±?0.9, 83.0?±?4.6, 322.0?±?6.0, 920.0?±?1.9, 72.0?±?1.5, 402.0?±?7.8, 10,235.0?±?7.0, 12,336.0?±?2.6 and 59.9?±?0.3 mg?kg(-1), respectively, in all the samples analysed. 相似文献
16.
A systematic analytical procedure for the determination of some trace impurities in iron matrices was developed by employing both direct and destructive neutron-activation techniques. Irradiations in fast neutron fluxes, selective activation by epithermal neutrons and coincidence γ-spectrometry measurements were used in some cases, in order to improve the sensitivity for non-destructive analysis; for destructive methods, radiochemical separations based on ion exchange and solvent extraction were applied. Procedures are described, and some results of the determination of low concentrations of Al, Mn, Ti, V (non-destructive), P, S, Zn (destructive) and As, Co, Cr, Cu, Mo, Ni, Sc, W (both methods) in iron are reported and discussed. 相似文献
17.
T. Takeuchi Y. Nakano T. Fukuda I. Hirai A. Osawa N. Toyokura 《Journal of Radioanalytical and Nuclear Chemistry》1997,216(2):165-169
Instrumental neutron activation analysis was applied to the determination of trace impurity elements in a silicon single crystal. Impurity concentrations in polysilicon melt were compared with those in a single crystal. Impurity concentrations in artificial quartz were also compared with those in natural quartz. Segregation coefficients in Au, Ir and Sb were determined at different concentrations. The segregation coefficient of an element in a silicon single crystal is constant over a critical concentration, it becomes larger gradually under the critical one, and at last it becomes larger than 1. 相似文献
18.
Reitznerová E Amarasiriwardena D Kopcáková M Barnes RM 《Fresenius' Journal of Analytical Chemistry》2000,367(8):748-754
Determination of seven elements (Cu, Fe, Mg, Mn, Pb, Sr and Zn) in whole enamel and surface layers of extracted non-carious human teeth by FAAS, ETA AAS, ICP-AES and ICP-MS (Pb) is demonstrated. Techniques are described for obtaining whole enamel and its acid dissolution. Fifty microm width enamel layers from outer enamel surface to a 200 microm depth were successively etched in 1 mL of 3 M HClO4 for 3 min dissolution periods. Enamel samples were analyzed for populations under and over 20 years of age and enamel from Bronze Age teeth. Concentrations of microelements in the whole enamel and in the first surface layer (50 microm depth) were compared. With exception of Sr and Mg, all elements show significantly higher concentrations in the first layer than in whole enamel and higher concentration in teeth of individuals over 20 years, which demonstrate the cumulative effect of these elements. The Cu, Fe, Mn, Pb and Zn concentrations in four layers of erupted and non-erupted teeth decreased while Mg and Sr concentrations increased toward enamel-dentine junction. The concentrations of most elements were almost constant as they approached the 150 microm layer. This concentration gradient may result from interaction between saliva and teeth and supports the hypothesis that the surface de- and re-mineralization process is effective at most to 150 microm from the enamel surface. 相似文献
19.
Jun Yoshinaga Masatoshi Morita Kensaku Okamoto 《Analytical and bioanalytical chemistry》1997,357(3):279-283
A new human hair certified reference material (NIES CRM No. 13) for mercury speciation and trace element analysis was prepared
at the National Institute for Environmental Studies (NIES), Environmental Agency of Japan. Scalp hair from Japanese males,
which is identical with the original material for the previous human hair CRM (NIES CRM No. 5), was used. Special attention
was paid to reduce contamination from a grinding vessel during the preparation procedure. A newly-prepared ceramic/Teflon
disc mill was used for cryogenic grinding of the hair. 1,000 bottles (3 g each) were produced after sieving and blending of
the hair powder. Certified values for total mercury and methylmercury, as well as other trace elements of toxicological and
nutritional significance (antimony, cadmium, copper, lead, selenium, and zinc), were determined based on analyses from extensive
collaborations. Reference values for 12 elements (aluminium, arsenic, barium, calcium, cobalt, iron, magnesium, manganese,
silver, sodium, sulfur and vanadium) were also given.
Received: 8 February 1996/Accepted: 4 April 1996 相似文献
20.
Jun Yoshinaga Masatoshi Morita Kensaku Okamoto 《Fresenius' Journal of Analytical Chemistry》1997,357(3):279-283
A new human hair certified reference material (NIES CRM No. 13) for mercury speciation and trace element analysis was prepared
at the National Institute for Environmental Studies (NIES), Environmental Agency of Japan. Scalp hair from Japanese males,
which is identical with the original material for the previous human hair CRM (NIES CRM No. 5), was used. Special attention
was paid to reduce contamination from a grinding vessel during the preparation procedure. A newly-prepared ceramic/Teflon
disc mill was used for cryogenic grinding of the hair. 1, 000 bottles (3 g each) were produced after sieving and blending
of the hair powder. Certified values for total mercury and methylmercury, as well as other trace elements of toxicological
and nutritional significance (antimony, cadmium, copper, lead, selenium, and zinc), were determined based on analyses from
extensive collaborations. Reference values for 12 elements (aluminium, arsenic, barium, calcium, cobalt, iron, magnesium,
manganese, silver, sodium, sulfur and vanadium) were also given. 相似文献