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1.
Appl Radiat Isot ; 52(1): 147-51, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10670935

RESUMO

Three different types of glass and four different kinds of aluminum sheet have been analyzed using neutron activation analysis. The irradiation facilities of the first Egyptian research reactor (ET-RR-1) and a hyper-pure germanium (HPGe) detection system were used for the analysis. Among the 34 identified elements, the isotopes 60Co, 65Zn, 110mAg, 123mTe, 134Cs, 152Eu and 182Ta are of special significance because of their long half-lives, providing a background interference for analyzed samples. A comparison between the different types of containers was made to select the preferred one for sample irradiation.

2.
Appl Radiat Isot ; 55(4): 569-73, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11545513

RESUMO

The technique of instrumental neutron activation analysis was applied as a sensitive nondestructive analytical tool for the determination of heavy metals and rare earth elements in phosphate fertilizer ingredients. The contents of heavy metals Fe, Zn, Co, Cr and Sc as well as rare earth elements La, Ce, Hf, Eu, Yb and Sm were determined in four samples representing the phosphate fertilizer components (e.g. rock phosphate, limestone and sulfur). These samples were collected from the Abu-Zabal phosphate factory in El-Qalubia governarate, Egypt. The aim of this study was to determine the elemental pattern in phosphate ingredients as well as in the produced phosphate fertilizer. Fair agreement was found between the results obtained for the standard reference material Soil-7 and the certified values reported by the International Atomic Energy Agency. The results for the input raw materials (rock phosphate, limestone and sulfur) and the output product as final fertilizer are presented and discussed.

3.
Appl Radiat Isot ; 55(6): 853-60, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11761110

RESUMO

Geological materials usually contaminated with naturally occurring radioactive materials (NORM) have become a focus of great attention. These NORM under certain conditions can reach hazardous contamination levels. Some contamination levels may be sufficiently severe that precautions must be taken. The present study deals with 60 geological samples (marble and granite) from both Egyptian and foreign locations. The studied samples were analyzed and the concentrations in Bq/kg dry weight of radioisotopes were determined by gamma-ray spectrometry using hyper-pure germanium (HPGe) detector in Bq/kg dry weight. The absorbed dose rate due to the natural radioactivity in the samples under investigation ranged from 2.45 +/- 0.07 to 64.44 +/- 1.93 nGy/h for marble and from 41.55 +/- 1.25 to 111.94 +/- 3.36 nGy/h for granite. The radium equivalent activity varied from 5.46 +/- 0.16 to 150.52 +/- 4.52 Bq/kg for marble samples and from 229.52 +/- 6.89 to 92.16 +/- 2.76 Bq/kg for granite. The representative external hazard index values for the corresponding samples are also estimated and given. The radon exhalation rates for marble and granite samples were also calculated by using solid state nuclear track detector (CR-39). The value of radium exhalation rate varied from 8.0 +/- 2.39 to 30.20 +/- 5.06 Bq/m2/d for marble and 6.89 +/- 1.72 to 25.79 +/- 4.38 Bq/m2/d for granite and the effective radium content was found to vary from 1.700 +/- 0.51 to 6.42 +/- 1.08 Bq/kg for marble and 1.29 +/- 0.32 to 5.63 +/- 0.96 Bq/kg for granite. The values of the radon exhalation rate and effective radium content are found to correspond with the values of uranium concentration measured by the HPGe detector in the corresponding sample.

4.
Appl Radiat Isot ; 55(6): 873-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11761112

RESUMO

The level of natural radioactivity in soil of 30 mining samples collected from six locations in southern Egypt was measured. Concentrations of radionuclides in samples were determined by gamma-ray spectrometer using HPGe detector with a specially designed shield. The obtained results of uranium and thorium series as well as potassium (K-40) are discussed. The present data were compared with data obtained from different areas in Egypt. Also, a solid state nuclear track detector SSNTD (Cr-39) was used to measure the radon concentration as well as exhalation rate for these samples. The radon concentrations were found to vary from 1.54 to 5.37 Bq/kg. The exhalation rates were found to vary from 338.81 to 1426.47 Bq/m2d. The values of the radon exhalation rate are found to correspond with the uranium concentration values measured by the germanium detector in the corresponding soil samples.

5.
Appl Radiat Isot ; 54(3): 559-62, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11214893

RESUMO

Elemental analysis of two iron ores and initial industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were performed by the instrumental neutron activation analysis technique. Five samples of each type were irradiated for 48 h in a thermal neutron flux of 4 x 10(12) n/cm2 s in the first Egyptian research reactor ET-RR-1. Also, the Pneumatic Irradiation Rabbit System (PIRS), attached to the reactor ET-RR-1 in Inshass, was used to measure short-life elements. The gamma-ray spectra were obtained with a hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. Implications of the elemental concentration values obtained are presented.

6.
Appl Radiat Isot ; 57(3): 427-36, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12201151

RESUMO

Natural radioactive materials under certain conditions can reach hazardous radiological levels. The natural radionuclide (238U, 232Th, 40K) contents of rock samples at various locations in the North Tushki area were investigated using gamma-spectrometric analysis. Estimates of the measured radionuclide content have been made for the absorbed dose rate of gamma radiation. The equivalent radium (Req) and the external hazard index (Hex) which resulted from the natural radionuclides in soil are also calculated and tabulated. The studied samples have been collected from various rock exposures in the North Tushki area. The distribution of major oxides, U and Th were studied. It is found that the enrichment and depletion of the major oxides are mainly due to the effect of hydrothermal alteration, which caused mobility of some major oxides, which increases some elements and decreases others. It is important to mention that the study area is far from the development region of the Tushki project and is only a local hazard. Therefore, additional regional studies of the Tushki Project area should be under taken to explore any unexpected environmental hazard due to the high concentration of the radioactive elements, which have been observed at its north boundary.

7.
Appl Radiat Isot ; 51(1): 131-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10376325

RESUMO

Heavy metals and rare earth elements in two types of cigarettes were studied. The contents of trace elements were determined by using delayed neutron activation analysis. In the present study 11 elements have been detected in popular and fine brand cigarettes marketed in Egypt. Evaluation of these elements with their potential hazards for smokers is briefly discussed. The material balance (source and sink) for each element was determined. Also the ratio of element recovery to the total amount was assessed.


Assuntos
Metais Pesados/análise , Metais Terras Raras/análise , Nicotiana/química , Plantas Tóxicas , Antimônio/análise , Bromo/análise , Cromo/análise , Cobalto/análise , Ouro/análise , Ferro/análise , Netúnio/análise , Análise de Ativação de Nêutrons , Protoactínio/análise , Escândio/análise , Zinco/análise
8.
J Environ Sci (China) ; 13(1): 115-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11590711

RESUMO

Elemental analysis of iron ore samples and first industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were determined by instrumental neutron activation analysis technique. Five samples from each kind were irradiated for a 48 hours at a thermal neutron flux of 4 x 10(12) n/(cm2.s) in the first Egyptian research reactor ET-RR-1. Also the Pneumatic irradiation Rabbit system (PIRS) attached to the reactor in Inshass, was used to measure the elements of short-life time. The gamma-ray spectra were recorded by means of the hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. The long and short lived isotopes were considered. A comparative study and a discussion on the elemental concentration values are given.


Assuntos
Ferro/análise , Mineração/métodos , Egito , Análise de Ativação de Nêutrons
9.
J Environ Sci (China) ; 15(4): 570-6, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12974322

RESUMO

Major and trace element in seven different kinds of milk powder were studied. The concentration of 24 elements were determined by ICP-OES method, from these elements 9 elements determined by INAA. The determination of trace element contents of foodstuffs, especially milk as daily drink for all peoples age which being a complex food has great importance. The elemental analysis of milk is important both as an indicator of environmental contamination and because milk is a significant pathway for toxic metal intake and a source of essential nutrients for humans. The major elements are Ca, K, Mg, Na, P and S. While trace element are B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sb, Se, Sn, Sr, V, W and Zn. ICP-OES technique is shown to be a powerful tool for trace determinations in powder samples. This is shown by its use for analysis of a series of the milk powders mentioned and comparative results of other direct technique such as instrumental neutron activation analysis. Analysis of both standard reference material A-11 milk powder and NBS Orchard leaves for quality accurance had been completed, and used for a relative method calculate. The importance of the major and trace elements to human health was discussed.


Assuntos
Leite/química , Oligoelementos/análise , Animais , Humanos , Análise de Ativação de Nêutrons , Pós/química , Saúde Pública , Espectrofotometria Atômica
10.
J Environ Sci (China) ; 16(1): 94-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14971460

RESUMO

The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiated with reactor for 4 h (in the Second Research Egyptian Reactor(Et-RR-2)) with thermal neutron flux 5.9 x 10(13) n/(cm2 x s). The gamma-ray spectra obtained were measured for several times by means of the hyper pure germanium detection system(HPGe). Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure the emanation rate of radon for these samples. The radium concentrations were found to vary from 0.39-3.59 ppm and the emanation rates were found to vary from (0.728-5.688) x 10(-4) kg/(m2 x s). The elemental analysis of the ceramic tiles and ceramic composites have a great importance in assigning the physical properties and in turn the quality of the material.


Assuntos
Cerâmica/química , Radônio/análise , Oligoelementos/análise , Teste de Materiais , Análise de Ativação de Nêutrons
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