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1.
A sensitive method is described for the dctermination of parathion in air The air sample is drawn through filter paper or cellulose powder, winch traps both particles and vapour, and the parathion is reduced without heating by means of a zinc-copper couple in acid solution, followed by dia/otisation of the amimo derivative and coupling to give an azo dye An alternative procedure la described in winch the parathion is trapped on cellulose powder containing zinc dust, from which the reduced derivative is directly cluted  相似文献   

2.
The concentration and the sources of heavy metals (Pb, Cd, Zn and Cu) in house dust samples of nine selected houses of Jalil Town, Gujranwala, Pakistan are determined and a comparison with the concentration of these metals in respective street dust samples is given. Sources, exterior as well as interior are identified. The extent of contribution of lead in house dust from exterior sources and interior sources is calculated by determining the isotopic ratios in house dust, street dust and paint used in the houses. It is noticed in the case of well ventilated houses, that most of the heavy metal contribution is from the exterior sources. However, in less ventilated houses, contribution from the interior sources is also significant.  相似文献   

3.
This study is a one-year monitoring of the inhalable particulate matter (PM10) of Shanghai (from January 2006 to December 2006) to study PM10 pollution. Proton-induced X-ray emission (PIXE) was used to investigate the chemical elements in Shanghai PM10. The study finds seasonal variation in both mass concentration and of chemical elements in PM10. The results of the enrichment factor show that the chemical elements in the inhalable particles could be divided into two categories, soil elements from earth crust and anthropogenic pollution elements. The high enrichment factors suggest that anthropogenic activities were the dominant source for elements such as S, Cu, Cl, Zn, Pb and Br. Strong correlation of K, Ca, Fe and Ti, from factor analysis, indicates these elements coming from earth crust or soil, S, Zn and Pb from industrial pollution and/or traffic and Cl from coal combustion.  相似文献   

4.
Four different approaches to PIXE data obtained in repeated measurements on thick standards have been evaluated in terms of precision and accuracy. Both were found to be the best when determinations relative to an external standard were normalized to a composition assumed to be 100% oxides.  相似文献   

5.
Using 1.0 MeV protons on thick targets of zeolite pellets, aluminium and silicon were determined by PIXE. Results were compared with XRF data. The relative root mean square error was 3.7% and the results of the two methods agreed with a correlation factor of 0.991. PIXE analysis can be carried out on very small samples, while sample preparation involves minimal handling.  相似文献   

6.
The growing concern about air quality in harbours is a result of the high impact of the operations on human health and environment. Harbour activities such loading, unloading and transport of dusty materials are important emission sources of Atmospheric particulate matter (APM). The assessment of these fugitive emissions is a difficult task because they depend on the materials, the type of operation and the meteorological scenarios. The main objectives of this work were (1) to evaluate if the techniques k0-based Instrumental neutron activation analysis (k0-INAA) and Particle induced X-ray emission (PIXE) are suitable techniques to assess fugitive emissions in harbours and (2) to estimate the impact of harbour activities on APM levels and composition. Several experimental campaigns were carried out in a Portuguese harbour, during unloading operations of fertilizer and phosphorite provided from Syria and Morocco. PM2.5 and PM2.5–10 were collected, in polycarbonate filters, by Gent samplers. The techniques k0-INAA and PIXE were applied as sensitive analytical tools to perform a complete chemical characterization of the collected samples. Results showed that manipulation of these materials during harbour operations resulted in high emissions of particles, principally from the coarse fraction. These emissions were very affected by the granulometry and nature of the handled materials. Fertilizer emissions were characterized by high concentration of Ca, P, K, Cr, Br and Zn, whereas phosphorite handling contributed principally for the increase of Ca, P and Cr levels.  相似文献   

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8.
Determination of vanadium in animal tissues by PIXE and AAS   总被引:2,自引:0,他引:2  
Proton induced X-ray emission (PIXE) and atomic absorption spectroscopy (AAS) were used for vanadium determination in animal tissues. The vanadium concentration levels were determined in blood, kidneys and livers taken from rats. Two groups of the animals were treated with different diets. The diet for the first group was supplemented with vanadium compounds while the diet for the second one was assumed to be a normal diet. The second group was treated as control. In order to achieve the best minimum detectable limit (MDL)1 the samples were subject to a special sample preparation procedure. Blood and kidneys were mineralized with an APDC compound. The mineralization process was performed according to the procedure described previously.2 The application of PIXE3 is very useful for different types of samples. PIXE measurements were performed with a proton beam at the Institute of Nuclear Physics in Cracow, Poland while the AAS measurements were done at the Institute of Molecular Biology, Jagiellonian University, Poland. The concentration levels of vanadium in blood and kidneys are compared and discussed. There were no significant statistical differences between results of vanadium concentration levels determined by the abovementioned techniques. The PIXE technique had the advantage over the AAS technique of giving a broad spectrum of trace elements analyzed in a single measurement. Therefore with the help of sample preparation procedure the application of the PIXE method seems to be suitable for such analyzes.  相似文献   

9.
This is the first of a series of two papers intended to review the state-of-the-art knowledge on atmospheric PAHs, concerning their monitoring, sources and transformation processes in the atmosphere. The monitoring section briefly introduces this class of compounds, mainly focusing on the 16 PAHs indicated by the US-EPA as priority pollutants. These compounds undergo partitioning between the gas phase and particulate, which has to be considered in the choice of the sampling methodology. Furthermore, sampling artifacts may arise from further phase transfers inside the sampling device. After sampling, extraction, clean up and detection/quantification procedures will follow. They are closely related since the choice of the extraction technique will heavily condition the clean-up step, and both procedures will place demands on the performance of the detection technique (usually GC-MS or HPLC). This is particularly true in the case of complex samples such as those arising from atmospheric sampling. The sources of atmospheric PAHs are then discussed with a particular focus on receptor models, which can allow the apportionment of PAH sources based on concentration data that can be routinely obtained by pollution control networks.  相似文献   

10.
The distribution of minor and trace elements in biological samples is very informative for bio-medical and environmental research. Particle induced X-ray emission (PIXE) analysis is a powerful tool for this subject since it can analyze many elements in samples non-destructively at high sensitivity and, with an advantage of micro-beam scanning capability. Recent studies in Japan on the application of PIXE analysis to these fields are introduced in this paper. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

11.
Journal of Radioanalytical and Nuclear Chemistry - Nutrition and safety of foods is one of the more discussed topics in the modern society. We processed twenty food samples of the organic and...  相似文献   

12.
The use of particle induced X-ray emission (PIXE) and X-ray diffraction as complementary techniques for the characterization of mineral samples (clays) is presented. The fundamentals of PIXE experiments, the method for performing quantitative analysis, and the actual results are also discussed.  相似文献   

13.
Hypertrophic scars are a particular type of scar that can form after any type of dermal injury. They are unsightly, red, elevated above nomal skin level, itchy and painful. At present no-one knows why these scars form. Due to the differences between scar tissue and normal skin it was decided to analyse skin tissue which at a later date would be compared to scar tissue. Split skin graft (epidemis) samples as well as full thickness skin (epidemis to demis) tissue were analysed using PIXE and RBS with a 2 MeV proton beam. The epidemis was compared to the demis to see if there were any variations between the two. In all the samples P, S, Cl, K, Ca, Fe, and Cd were detected and in a majority of the samples Zn and Ba were found, using PIXE. It was found that, between the epidemis and demis, there was an significant increase in P in the epidermis in both full thickness and split skin graft samples. Complementary elemental analysis was also performed using neutron activation, and Br, Na and Zn were detected.  相似文献   

14.
T&#;m&#;sk&#;zi-Farkas  R.  Daood  H. G.  Polg&#;r  Zs.  Haj&#;s  Gy. 《Chromatographia》2006,63(13):S115-S118

In this work potato genotypes originated from an intensive resistance breeding programme that includes unique combination of resistance to several pathogens and consumer response were analysed for glycoalcaloid content by reversed phase high performance liquid chromatographic method. The glycoalcaloids were concentrated from potato samples by solid-phase extraction with a disposable C18 cartridge column. Nucleosil 100-5 C-18-AB column was used with 50% acetonitrile in phosphate buffer as the mobile phase. The method was validated according to calibration curve, precision and recovery tests, limit of detection and quantitation. The results indicated that as low as 0.27 µg mL−1 can be quantitatively determined by this method with 94–98% and 99% for recovery and precision, respectively. Hungarian potatoes were analysed by the adapted procedure for their glycoalcaloid content. The result showed that the tested Hungarian potato varieties contain glycoalcaloids between 0.09 and 15 mg 100 g−1. The content of glycoalcaloids in the new varieties of potato was lower than the limit of the Official Food Regulations.

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15.
Proton Induced X-ray Emission (PIXE) method is used for the determination of elemental concentrations in cancellous bone of human femoral head from five autopsies and seven patients with femoral neck broken. The specimen preparation and experimental procedure are described in detail. Using the t test, the results show that the concentrations of P, Ca, Fe, Cu, Sr in control group are higher than those in patient group, but the concentrations of S, K, Zn, Mn are not significantly different. The physiological functions of metallic elements in human bone are also discussed.  相似文献   

16.
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   

17.
Particle induced X-ray emission (PIXE) spectroscopy is a simple and convenient method of quantitative multielemental analysis with sensitivities in the μg/g range, that can be successfully used for trace analysis of metal ions in proteins or enzymes. However, due to its elemental character the technique alone is not a priori suitable for speciation. Keeping track of the metal ions of interest throughout a proper biochemical separation technique, on the other hand, could be a useful strategy for speciation. Different versions of thin layer electrophoresis (polyacrylamide gel, agarose or cellulose acetate electrophoresis) are very effective and sensitive methods to separate proteins or protein fragments. Due to the high absolute sensitivity of PIXE the metal ions concentrated in the narrow bands of an electropherogram can be in situ successfully detected. The present paper describes this unique combination of biochemical separation and ion beam analysis which significantly extends the information obtained from electrophoresis. Illustrative applications are given and the advantages and limitations of the method are discussed. Possible extensions of the technique are also outlined.  相似文献   

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20.
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   

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