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1.
The elements Cd, Cr, Cu, Mn, Ni, Pb and Zn were determined in dust samples collected from air conditioner (AC) filters from 15 commercial sites of Lahore using flame atomic absorption spectroscopy (FAAS). The elements Cr, Mn and Zn were also determined using instrumental neutron activation analysis (INAA). The results obtained showed that higher amounts of these metals were measured in these dust samples than normally found in soil. This was especially true for Cd, Cu, Pb and Zn. Generally the amounts of Cd, Cr and Mn did not vary throughout the city of Lahore but the amounts of the traffic related Cu, Pb and Zn elements had the more variable ranges of 30–140, 30–230 and 74–2810 mg/kg respectively. The concentrations obtained for Cr, Mn and Zn by INAA were found to be higher than those obtained using FAAS. Analysis of the data obtained showed the digestion procedure employed to be the possible cause for this occurrence. It was also found that Mn was being over-estimated by INAA due to the interference from the Mg peak.  相似文献   

2.
Harbour activities such as loading, unloading and transport of materials may be an important source of Atmospheric Particulate Matter (APM). Depending on the materials, the type of operation and the meteorological conditions, these activities may have an impact on the levels of APM around harbour areas. The aim of this work was to characterize the emissions of dust providing from operations associated with phosphorite handling in harbours. Phosphorite is a non-detrital sedimentary rock which contains high amounts of phosphate bearing minerals and is used for the production of phosphorous based fertilizers. When handled in harbours frequently cause visual and environment impacts due to its physical and chemical characteristics. The techniques Instrumental Neutron Activation Analysis and Particle Induced X-ray Emission were applied as sensitive analytical tools for the determination of heavy metals and rare earth elements in phosphorite and in the APM sampled in the harbour during the unloading operations. Results showed that manipulation of phosphorite during harbour operations resulted in high emissions of particles, principally from the coarse fraction. These emissions were enriched in rare earth elements and heavy metals and were very affected by the provenience of the phosphorite.  相似文献   

3.
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   

4.
In Parkinson disease Fe and other metals increase in Substantia Nigra(SN) and other basal nuclei. Since Fe can generate citotoxic free radicals,Neuromelanin (NM) could play an important protective role in neurons. In thiswork an original procedure for separation of NM, preparation of samples andanalysis is presented. The determination of SN and its NM elemental contentwas carried out by instrumental neutron activation analysis. Several actionswere taken to reduce the metal contaminations: use of high purity reagents,dissection of tissues with titanium coated tools and adequate processing ofsamples.  相似文献   

5.
The paper presents the chemical composition analysis results of 57 ancient clay bricks obtained from Buddhist sites of two major locations of Andhra Pradesh, India. Samples were analyzed by instrumental neutron activation analysis (INAA) using high flux reactor neutrons and high resolution gamma ray spectrometry. Major, minor and trace concentrations of 23 elements were determined by relative method of NAA. For the grouping/provenance study, statistical cluster analysis was performed using concentrations of 14 selected elements namely Sc, Cr, Fe, Co, Zn, Cs, La, Ce, Eu, Tb, Yb, Lu, Ta and Th. The cluster analysis results indicated two major groups, which are in good agreement with the collection history of samples. Accuracy of the method was evaluated by analyzing two IAEA reference materials, RMs SL-1 and Soil-7.  相似文献   

6.
Neuromelanin (NM) is an ubiquitary intraneuronal pigment in human brain and its abundance is probably related to neuronal vulnerability, especially in Parkinson Disease. In this and other neurodegenerative diseases an association was shown with endogenous accumulation and environmental exposure to metals. Melanins are strong metal chelators, therefore it is important to measure their content in brain regions and in their NMs. In this work the concentration of 18 elements was measured in each brain region and in the corresponding NM by instrumental neutron activation analysis.  相似文献   

7.
Journal of Radioanalytical and Nuclear Chemistry - For the first time, active biomonitoring was used to assess elemental content of atmospheric pollution in selected areas of the Western Cape...  相似文献   

8.
Two samples of Napoleon's hair were received for determination of arsenic, mercury and other trace elements by INAA. Before sample irradiation, the hairs were washed following the IAEA washing procedure. Two standard reference materials of GBW09101 (human hair) and NIST/SRM1572 (citrus leaves) were analyzed along with Napoleon's hair for quality control. Standardization was conducted by applying the k 0-method implemented in the program MULTINAA. The contents of arsenic and mercury as well as three additional elements chromium, antimony and zinc in Napoleon's hair are reported. Compared to the present normal levels, all of the determined elements in Napoleon's hair, except the mercury, are found to be irregular.  相似文献   

9.
Sorption of uranium and other heavy metals on hydroxyapatite   总被引:6,自引:0,他引:6  
The immobilization of UVI and PbII from aqueous solutions in a solid phase by interaction with calcium hydroxyapatite has been studied in batch experiments with increasing contact times. The results were compared with those previously found for CdII. All these elements are able to be efficiently immobilized by such a method. The sorbed quantities vary in the order Pb>U>Cd. The sorption mechanisms are element dependent. The dominant mechanisms are: dissolutionprecipitation with formation of an amorphous or microcrystalline phase for U, dissolution-precipitation with the formation of two new crystalline phases and with possible incorporation into the initial apatite for Pb, and intracrystalline diffusion and exchange for Cd.  相似文献   

10.
Instrumental neutron activation analysis (INAA) was used to determine metals (Ba, Co, Cr, Cs, Fe, Hf, Rb, Sc, Zn), semi-metals (As, Sb), actinides (U, Th) and rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu) in bottom sediments from one of the ponds of the Sewage Treatment Plant (STP) in São Paulo, Brazil. The results obtained were compared with the concentration determined in a soil profile and in a rock sample, in natura, representing the lithologies of the region, and indicated that only As, Cr and Zn can have their origin associated with the residues disposed around the pond.  相似文献   

11.
XRFS can be successfully used for routine on-line analysis of different agricultural products, for instance where food quality control is necessary. The optimization of the system for such purposes and the results obtained are shown on the example of the analysis of coffee.  相似文献   

12.
The placenta was used as an exposure index for the risk evaluation of prenatal fetal chemical exposure. Full-term placenta samples collected at maternity hospitals in 4 regions of different environmental pollutants and traffic density were examined for lead and cadmium contents using atomic absorption spectrometry (AAS). The results showed similar lead contents in placental samples from all selected regions, except for a small town with a lower traffic density. The findings may implicate traffic-related environmental lead pollution, rather than industrial sources. The highest concentration of cadmium was shown to be in the samples collected from the region with the highest proportion of smoking mothers (including passive smoking). Simultaneously, the placental samples were processed histochemically to determine the location of lead in the placental tissue (using light microscopy). The degree of placental metal contamination was done semiquantitatively, and the difference between the rural and industrial region was statistically compared. Parallel quantitative AAS analyses and semiquantitative histochemical lead analyses of human placental samples revealed analogous results regarding the level of placental contamination with metals.  相似文献   

13.
The placenta was used as an exposure index for the risk evaluation of prenatal fetal chemical exposure. Full-term placenta samples collected at maternity hospitals in 4 regions of different environmental pollutants and traffic density were examined for lead and cadmium contents using atomic absorption spectrometry (AAS). The results showed similar lead contents in placental samples from all selected regions, except for a small town with a lower traffic density. The findings may implicate traffic-related environmental lead pollution, rather than industrial sources. The highest concentration of cadmium was shown to be in the samples collected from the region with the highest proportion of smoking mothers (including passive smoking). Simultaneously, the placental samples were processed histochemically to determine the location of lead in the placental tissue (using light microscopy). The degree of placental metal contamination was done semiquantitatively, and the difference between the rural and industrial region was statistically compared. Parallel quantitative AAS analyses and semiquantitative histochemical lead analyses of human placental samples revealed analogous results regarding the level of placental contamination with metals. Received: 30 June 1997 / Revised: 21 December 1997 / Accepted: 30 December 1997  相似文献   

14.
Samples of natural and fertilised soils were collected from Al-Gheran region, west of Tripoli, Libya. The samples were investigated by means of INAA and ED-XRF for Al, Si, K, Ca, Sc, Cr, Mn, Fe, Co, Zn, Br, Rb, Sr, Y, Zr, Nb, Cs, Ba, Hf, Ta, Pb and Th. The results indicate that the concentrations of K, Ca, Zn, Sr and Pb are 2–4 fold higher in fertilised compared to natural soil, while the concentrations of Al, Si, Cr, Mn, Fe, Co, Rb, Y, Nb, Cs, Ba Ta and Th are nearly the same in all samples. Mn and Fe values in two arable soils have been found to be 4–6 times lower than the average concentration in the earth's surface soils. This study concludes that, although the levels of some trace elements important for human health are very low in both natural and fertilised soils. Further research is needed to understand the full significance of the distribution transfer and toxicity of trace elements introduced in imported fertilisers.  相似文献   

15.
For the first time the moss biomonitoring technique has been applied to air pollution monitoring in Central Russia (Tula region). INAA at the IBR-2 reactor has made it possible to determine the content of 33 elements in mosses collected at 83 sampling site. In addition to NAA, flame AAS (atomic absorption spectrometry) was applied to determine the content of Cd, Cu and Pb. Factor analysis was applied to determine possible sources of trace element deposition in Tula mosses. The geographical distribution of factor scores and some element distribution maps over the investigated territory are presented.  相似文献   

16.
The effect of age and sex was investigated on the concentration of chemical elements in intact cancellous bone of iliac crest of 74 relatively healthy, 15–55 years old women (n = 29) and men (n = 45). Concentrations of Ca, Cl, K, Mg, Mn, Na, P, and Sr in bone samples were determined by instrumental neutron activation analysis using short-lived radionuclides. Mean values (M±S.E.M.) of the mass fraction of the investigated elements (on dry weight basis) for female and male all together were: 127±4 g/kg, 1620±80 mg/kg, 1310±70 mg/kg, 1550±50 mg/kg, <0.32±0.02 mg/kg, 4240±110 mg/kg, 61.8±1.8 g/kg, and 235±18 mg/kg, respectively. The statistically significant (≤0.05) decrease of Ca, Mg, and P concentrations in the iliac cancellous bone with age was found only for women. Sex-related comparison has shown that the mean values of Mg mass fractions in male bone samples were less than in female ones.  相似文献   

17.
Summary Two methods are presented for the extractive separation of rhenium from molybdenum and other heavy metals in hydrochloric acid solution. In the first method, Mo(VI) and Re(VII) are reduced by hydrazine in strong hydrochloric acid solution to Mo(V) and Re(IV). The former is then extracted intoiso-amyl acetate. The Re(IV) remaining in the aqueous phase is oxidised to Re(VII) and determined by known procedures. In the second method, Re(VII) and other ions in 1–1.3N HCl are boiled with hydrazine sulphate for 5 minutes. After adding EDTA to complex Mo(V) and adjusting the solution to 0.33N HCl, rhenium is extracted into chloroform containing 1% tribenzylamine, and is recovered by shaking with water having sufficient ammonia to neutralise the acid and a little hydrogen peroxide.
Zusammenfassung Zwei Arbeitsweisen für die extraktive Trennung des Rheniums von Molybdän und anderen Schwermetallen in salzsaurer Lösung wurden angegeben. Bei dem ersten Verfahren werden Mo(VI) und Re(VII) mit Hydrazin in stark salzsaurer Lösung zu Mo(V) und Re(IV) reduziert. Ersteres wird dann mit Isoamylacetat extrahiert. Re(IV) verbleibt in der wäßrigen Phase, wird zu Re(VII) oxydiert und auf bekannte Art bestimmt. Beim zweiten Verfahren werden Re(VII) und die anderen Ionen in 1- bis 1,3-n Salzsäure 5 Minuten mit Hydrazinsulfat gekocht. Nachdem man ÄDTA zur Komplexierung des Mo(V) zugesetzt und die Lösung auf 0,33-n an Salzsäure eingestellt hat, wird Rhenium mit einer 1%igen Lösung von Tribenzylamin in Chloroform extrahiert. Die Rückextraktion erfolgt mit Wasser, worin Ammoniak (zur Neutralisation der Säure) und etwas Wasserstoffperoxid gelöst sind.
  相似文献   

18.
In various samples of Mytilus galloprovincialis, 210Po was determined by alpha-spectrometry while Mn, Fe, Ni, Cu, Zn, Cd, Sn, Hg and Pb by energy dispersive, polarised X-ray fluorescence spectrometry (EDPXRF). The mussels of different sizes were taken from 7 sites in the central Adriatic Sea along the Marche coastal region during the four seasons of the year. 210Po activity concentration ranged between 57 and 343 Bq·kg−1 dry weight. The concentration ranges of heavy metals (μg·g−1 dry weight) were as follows: Mn: 72.9–83.1; Fe: 45.1–754; Ni: 1.3–7.6; Cu: 17.9–156; Zn: 60.9–189; Cd: 0.6–1.0; Sn: 0.6–3.9; Hg always <0.5; Pb: 2.0–9.0. The data obtained depend upon the site and the period of the sampling and they are also compared with those obtained by other authors for the same organism in the Mediterranean and other Italian seas.  相似文献   

19.
Determination of trace elements in honey by INAA in Turkey   总被引:2,自引:0,他引:2  
Instrumental neutron activation analysis was applied to the determination of As, Cr, Sb, K, Br, Zn, Fe, Co in Turkish honey. Irradiation time was 6 h underwater at a thermal flux of 1013 n cm–2 s–1; cooling times of 100 h and 3–4 weeks and counting times of 5000 s and 80.000 sec were used. The detection limit for As is 0.01 ppm for honey matrix under these conditions. A technique was developed for sealing the quartz tube containing the honey with flame.  相似文献   

20.
Highly enriched concentrations of several heavy metals have been found in municipal solid waste incinerator (MSWI) ash. In an effort to identify possible sources of these metals in MSWI ash, a variety of disposable household plastic products was examined for heavy metal content. Using both thermal and epithermal neutron activation analysis (NAA) along with Compton suppression techniques, concentrations of several trace and heavy metals including Ag, As, Au, Ba, Br, Cd, Cr, Cu, Fe, Mn, Ni, Sb, Se, Sn, Sr, V, W and Zn were determined. Results indicate a wide range of concentrations for these elements, with large variations in plastics of similar color and intended use. As limits dealing with heavy metal content of consumer products are lowered, NAA techniques will provide a useful method for verification of product compliance.  相似文献   

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