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1.
Journal of Radioanalytical and Nuclear Chemistry - Particle induced X-ray emission technique was used to obtain the serum elemental profile of healthy subjects and breast cancer patients (BCPs)...  相似文献   

2.
Calcification of implanted biological heart valves leads to malfunction after a certain period. The substance mainly responsible for accumulated calcium deposits in glutaraldehyde. The study was divided into was phase: chemical detoxification of the tissue by glutaraldehyde extraction to minimize calcification, and a subsequent PIXE analysis of more than 80 aortic wall samples to examine the efficiency of the detoxification process.  相似文献   

3.
4.
Guangdong Province of China is the highest incidence place of naso-pharyngeal cancer in the world. The concentrations of 19 trace elements in hair of 90 naso-pharyngeal cancer patients in Guangdong Province have been measured by the PIXE technique. By using the Maximum Probable Discrimination Method to distinguish naso-pharyngeal cancer patients from healthy people, we get up to 91.1% validity of differential diagnosis and get some indication that special trace elements participate in carcinogenesis.  相似文献   

5.
Elemental concentrations in breakfast cereals consumed in Mexico were measured using Particle induced X-ray emission with 1.7 MeV protons and X-ray fluorescence with a Rh X-ray tube operating at 35 kV. The specimens, obtained from packages purchased in markets, were freeze dried, ground and pelletized. Standardization was done with tomato, spinach, peach, and orchid leaves NIST standard reference materials, and analytical accuracy verified with NIST 3233 standard reference material (fortified cereal). The concentrations of nine elements did not agree with values quoted in the packages. Therefore, there may be inaccurate official estimations of Mexican population nutrient intakes.  相似文献   

6.
Thick-target Particle Induced X-ray Emission (TTPIXE) was used for the quantitative determination of trace-element concentrations in trunk wood. The wood samples were preconcentrated by dry ashing to improve the reliability of the sampling and the sensitivity of the analytical method. Samples of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) were collected from a polluted area (Harjavalta) as well as from a relatively nonpolluted area (Merimasku) in southwestern Finland. The elements studied were P, S, K, Ca, Mn, Fe, Ni, Cu, Pb, Rb, Sr, Ba, Cd and Ag. TTPIXE combined with dry ashing is a sensitive and reliable analytical technique for most elements studied. The method was validified by using several certified reference materials and also by ICP-MS analysis. Due to the low ash content (0.2–0.4%) in wood a high preconcentration factor can be obtained. Differences in trace-element uptake were observed between the two tree species studied. Trunk wood from the polluted area contained higher concentrations of heavy metal ions. Received: 30 August 1996 / Revised: 11 October 1996 / Accepted: 3 November 1996  相似文献   

7.
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   

8.
Thick-target Particle Induced X-ray Emission (TTPIXE) was used for the quantitative determination of trace-element concentrations in trunk wood. The wood samples were preconcentrated by dry ashing to improve the reliability of the sampling and the sensitivity of the analytical method. Samples of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) were collected from a polluted area (Harjavalta) as well as from a relatively nonpolluted area (Merimasku) in southwestern Finland. The elements studied were P, S, K, Ca, Mn, Fe, Ni, Cu, Pb, Rb, Sr, Ba, Cd and Ag. TTPIXE combined with dry ashing is a sensitive and reliable analytical technique for most elements studied. The method was validified by using several certified reference materials and also by ICP-MS analysis. Due to the low ash content (0.2–0.4%) in wood a high preconcentration factor can be obtained. Differences in trace-element uptake were observed between the two tree species studied. Trunk wood from the polluted area contained higher concentrations of heavy metal ions. Received: 30 August 1996 / Revised: 11 October 1996 / Accepted: 3 November 1996  相似文献   

9.
Ancient ceremonial potteries belonging to pre-Columbian cultures in Chile, South America, are decorated with three different colours, red, white and black. Samples of these colours have been analyzed with induced X-ray fluorescence by a 6.6 MeV proton beam. The analyses show clearly distinct patterns for each pigment and also denote differences between the same colour in two cultures. Eight elements, from aluminium to copper were detected.Under partial support from the Departamento Técnico de Investigación de la Universidad de Chile, Grant 2438-8833.  相似文献   

10.
Summary This on-going study was conducted on erythrocytes to further establish the content of elements of blood fractions from patients undergoing Coronary Artery Bypass Grafting (CABG) surgery. As the quality and quantity of elements in these samples were unknown, proton induced X-ray emission (PIXE) analysis was chosen for its multi-elemental analysis capabilities on small mass samples. Previous work demonstrated the detection of several elements using PIXE analysis and that the elemental concentrations of S, Cl, Ca and Fe were worthy of note. It is indicated that continuing analysis of these cell fractions may be significant in the study of trace element metabolism as it provides insight into understanding mechanisms for preventative, diagnostic and therapeutic purposes and hence a patient's state of health. The analysis of erythrocytes was conducted at pre, during and post-operative timepoints to investigate the changes that occur during and post-surgical intervention. Elements Na, Mg, Si, P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb were detected in erythrocytes at all surgery timepoints and from normalized graphs, elements S, K and Fe revealed that the changes in concentration through surgery followed an almost identical pattern. It is anticipated that statistical correlation and interpretation of data may provide, in the long-term, information that could have an impact on the patients' rate of recovery or appropriate aftercare.  相似文献   

11.
Trace elemental analysis was carried out in various parts of 10 anti-epileptic medicinal plants using PIXE technique. A 3?MeV proton beam was used to excite the samples and spectra were recorded using a Si(Li) detector. Data analysis was done using Gupix Software. The elements Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Br and Sr were identified and their concentrations estimated. The presence of some of these trace elements is correlated with the anti-epileptic curative property of these plants.  相似文献   

12.
The minor and trace element content in coal is of great interest due to the potential impact on the environment from the release of these elements during combustion. Reducing the concentrations of potentially hazardous elements in coal prior to combustion is one way of dealing with this issue. In this research particle induced X-ray emission (PIXE) was used to investigate a hydrothermal leaching process for the removal of trace elements from a bituminous coal. The leaching agents HNO3 and NaOH were evaluated along with the effects of process parameters (temperature, pressure, and time) on the method's effectiveness. The variable with the greatest influence was the leaching agent itself. HNO3 was determined to be more effective than NaOH in reducing elemental concentrations for nearly all the elements determined. Increasing the temperature did result in greater reductions for some elements (Cl, Br, Zn) whereas increasing the pressure and duration of the leaching process had minimal impact on reductions, in elemental concentrations.  相似文献   

13.
Fingernails of pathologically diagnosed normal people, light esophageal epitheliosis patients, severe esophageal epitheliosis patients and esophageal cancer patients were irradiated and their elemental contents were determined by INAA. Multivariate statistical treatment of Ca, Cl, K. Mg, Se and Zn data shows that esophageal cancer patients are distinguishable from non-cancer patients. The accuracy computed by neural networks is greater than 80%.  相似文献   

14.
The procedure for using proton induced X-ray emission (PIXE) in conjuction with the method of spotting for qualitative and quantitative multi-element analysis of drinking water in eight cities of Jordan is discussed in this article. It is likely that this method of preconcentration can be directly incorporated into field sampling procedures, thus eliminating the problems of sample contamination or trace element losses by absorption on container walls, the significance of some of the elements found in the samples is discussed.  相似文献   

15.
A simple, sensitive and fast procedure for analysis of liquid samples called flowing sample neutron activation analysis has been established based on measurement of short-lived radionuclides. This newly developed method involves continuous flowing of sample between an irradiation cell and measurement station. This arrangement makes it easy to analyze a large volume of sample and thus preconcentration steps can be avoided. Moreover, flowing sample technique feeds detector with fresh irradiated material, which maintains constant dead time during whole time of measurement; hence improves accuracy of the method. The method was tested for its repeatability, detection limits and sensitivity. Obtained limits of detection are favorably comparable with those already published in literature.  相似文献   

16.
塞曼石墨炉原子吸收法直接测定血清中的硒   总被引:12,自引:0,他引:12  
采用硝酸钯为硒的基体改进剂,用塞曼效应扣除背景,对消化后的血样直接进行测定。该法的检出限为6.0ng/mL,线性范围10ng/mL-136ng/mL,回收率为94.8%-102.5%。  相似文献   

17.
The technique of instrumental neutron activation analysis, involving neutron fluxes of 1014 n·cm−2·sec−1 and high resolution Ge(Li) gamma-detectors, has been applied to the analysis of bullet lead and jacket material. Radiochemical separation of the majority of the radioantimony from the irradiated bullet material was performed, with the objective of facilitating measurement of other elements present. Eight elements were measured in bullet lead and four in jacket material. Concentration variations between the varieties of ammunition studied indicate that more extensive studies, directed to possible ammunition characterisation, would be worthwhile.  相似文献   

18.
The proton particle induced X-ray emission (proton PIXE) technique has been employed to study the heavy element status (essential and toxic) in five different varieties of pulses commonly cultivated and consumed in Bangladesh. In this analysis, the samples were irradiated in air with 2 MeV protons having 30 nA beam intensity for characteristic X-ray excitation. For 40 μC irradiations, the concentration of ten elements (K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Br, and Rb) was determined by comparison with a calibration obtained from the NBS orchard leaf standard, SRM 1571. In a comparative study with atomic absorption spectrophotometric (AAS) measurements of some elements in lathyrus sativus, the data were found to be in good agreement. The results obtained from the present study are discussed and compared with available data.  相似文献   

19.
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study was to find trace elements that increase risk of breast cancer based on the deviation of the concentration of trace elements...  相似文献   

20.
Whole blood from patients undergoing Coronary Artery Bypass Grafting (CABG) operations was separated into leukocyte subfractions of polymorphonuclearcytes (PMN) and peripheral blood mononuclear cells (PBMC). Blood samples were collected and analyzed at various timepoints to determine the elemental composition to provide a better understanding of recovery mechanisms and to indicate complications that may occur post-operatively. Proton induced X-ray emission (PIXE) analysis and Rutherford backscattering spectrometry (RBS) using the University of Surrey microprobe was employed to determine the concentrations of a range of elements. Accurate two-dimensional PIXE analysis however, requires knowledge of the sample matrix composition. These samples, on the other hand, showed varying thickness, lacked matrix homogeneity and displayed non-uniform trace element distribution. This paper discusses the results and problems associated with routine PIXE analysis and demonstrates the potential ability of ion beam analysis (IBA) depth profiling software, previously unused in PIXE analysis, to model a RBS spectrum of inhomogeneous, multi-layered samples prior to performing PIXE analysis.  相似文献   

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