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1.
The elemental composition of human hair obtained from different studies at Surrey University over a period of 25 years has been recorded and forms part of a database, for biological and environmental samples, which is being developed. Instrumental neutron activation analysis (INAA), using reactor neutrons, was the principal method employed and from which reported data are presented.Elemental concentrations of Br, Ca, Ce, Cl, Co, Cr, Cs, F, Fe, Hf, K, Mg, Mn, Na, Rb, Sb, Sc, Se, V and Zn were obtained and recorded in the database. Chronological variations in two sets of subjects separated by a period of time of 16 years are also given. Variations in the concentration values of some elements related to the state of health and disease were reported for hair samples collected from subjects suffering from manic depression, senile dementia and breast cancer. Concentration values of some elements with relation to the nationality of subjects from Bulgaria, England, Kenya, Nigeria and Wales are presented and compared. This study is part of on-going research in the analysis of biomedical and bioenvironmental materials. The database is still in its infancy. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
2.
Instrumental Neutron Activation Analysis (INAA) and Proton-Induced X-ray Emission (PIXE) analysis (employed as a complementary technique) have been used to determine the concentration of 11 elements in blood samples and its components erythrocytes and plasma obtained, from three groups of subjects in Nigeria viz: sickle cell anaemia (SCA) subjects, subjects with sickle cell trait and normal control subjects. The results suggest that SCA subjects have significantly higher concentrations of Na, Cl, Ca and Cu in their whole blood and erythrocytes and a higher concentration, of Cl and Cu in their plasma relative to the control subjects. Furthermore, a significantly lower concentration of K, Fe, Zn, Se, Br and Rb were found in the whole blood and erythrocytes of the SCA subjects as compared to the controls while the concentration of K and Fe in the plasma of the SCA subjects were however, found to be significantly higher than that of the control group. The study also shows that there was no significant differences between the concentration of these 11 elements in the group with sickle cell trait and the normal control group.  相似文献   
3.
Very few publications have quoted differences between the same regions in both the right and left hemispheres of the human brain. It may be possible that that the two hemispheres have different trace elemental concentrations, since it is known that they both have different functions. In this study, three brain regions from both the right and left hemispheres of the cortex have been sampled from five elderly individuals (three 'normal' and two Alzheimer's disease) and their elemental concentrations have been determined by instrumental neutron activation analysis (INAA).  相似文献   
4.
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   
5.
Journal of Thermal Analysis and Calorimetry - This study explored the predictive modelling of the pyrolysis of rice husk to determine the thermal degradation mechanism of rice husk. The study can...  相似文献   
6.
Airborne particulate matter collected during the Harmattan season at Kano in the northern part, and Ile-Ife in the southern part of Nigeria was analyzed for about 30 elements by a combination of instrumental neutron activation analysis and X-ray fluorescence analysis. Although the total suspended particulate concentration (ng/m3) is much higher in Kano than Ife, the elemental composition at both locations is very similar and cluster analysis shows a strong correlation between the two, indicating a common origin for particulates. Particle-size distribution studies show that Kano dust is mainly coarse while Ife dust is mainly fine. The crustal-type elements are mainly concentrated in the coarse particles (3 m) at both locations while the conventional anthropogenic elements are hosted mainly by the fine particles (0.49 m and below).  相似文献   
7.
Three nuclear and atomic-based techniques for elemental analysis of air-particulate samples are discussed in terms of their usefulness in an environmental monitoring and impact assessment programme, supported by the European Economic Community, in Nigeria. Instrumental neutron activation analysis (INAA) and proton induced X-ray emission (PIXE) analysis are compared with respect to the number of elements detected and the detection limits obtained for air-particulate matrices. The latter is used in conjunction with Rutherford backscattering spectrometry (RBS) in order to correct for variations in matrix composition. A scanning electron microprobe (SEM) with analytical facilities is also employed mainly for characterization of the air-particulates through measurement of particle size and morphology. The value of carrying out statistical analysis for differentiating between collection sites or sources of pollution is emphasised. Reference to results obtained from the analysis of air-particulates collected during the Harmattan season at Kano and Ife, separated by about 1000 km place the problem in context and serve to illustrate the requirements.  相似文献   
8.
Ashes of medicinally used tropical plant woods collected in the southern part of Nigeria were analyzed for up to 24 elements using Instrumental Neutron Activation Analysis techniques (INAA). The plants are:Azadirachta indica, Astonia congensis, Chlorophora excelsa, Antiaris africana andBrachystegia euricoma. Concentrations of 24 major, minor and trace lements were determined. The result of elemental contents were discussed with reference to the medicinal uses of the plant.  相似文献   
9.
A dual energy X-ray absorptiometry (DEXA) system has been employed to measure the bone mineral density (BMD) of children with inflammatory bowel disease (IBD); Crohn's disease (CD) and ulcerative colitis (UC) at diagnosis. The results of the study indicate that even at diagnosis, a significantly reduced bone mineral density measured in terms of the Z-score, was observed in the lumbar spine and whole body of the IBD subjects. This was found to be more pronounced in Crohn's disease than in the ulcerative colitis subjects. Furthermore, the study was extended to investigate the elemental composition of hair of IBD subjects and age matched controls using instrumental neutron activation analysis (INAA). The concentrations of 11 elements; Al, Br, Ca, Cl, Cu, I, K, Mg, Mn, Na and V were determined. A significantly reduced concentration of Ca, Cu, K, Mn, and V were observed in the hair of IBD subjects as compared to the control group. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
10.
A study was undertaken to determine the concentration of selenium in whole blood, erythrocytes and plasma in samples obtained from three groups (each group consisting of one male and one female subject) given as a supplement a commercial product containing the element, together with vitamins A, C and E. Blood samples were obtained on one-day-a-week basis from each group, over a period of 75 days, both in the morning and in the afternoon, as part of a gastric function investigation, in which the subjects were given orange juice after fasting. Results indicate that the level of selenium in whole blood and its components increases with dose and time and that concentrations of the element are maintained for at least 45 days following cessation of supplementation. The influence of the supplement on some electrolytes such as Na, Cl, Br and Rb was also investigated.  相似文献   
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