Showing results for: gamma ray Articles
-
Heat and Moisture Transfer Characteristics of Compacted Mackenzie Silt
The heat and moisture transfer characteristics of a silt from the Mackenzie River Valley have been determined in a laboratory investigation. A dual gamma-ray scanner was used to measure the changes in density and volumetric moisture content along the soil samples. The coefficients of soil-water diffusivity under isothermal conditions and under temperature gradients have been obtained. The ...
-
Value addition in diamonds and other gemstones by nuclear radiation: the phobias and safety considerations
Four Cs, namely colour, clarity, carat (weight) and cut, primarily determine the price of a gem. Neutron irradiation, gamma rays and electron beams can be used to enhance the colour and clarity of aquamarine, quartz, tourmaline, kunzite, topaz, pearls and, most importantly, diamonds. Imparting colour and clarity to these gems that are otherwise devoid of these attributes results in significant ...
-
The characterisation of gamma photon incoherent scattering on free and binding electrons by Compton spectroscopy
The incoherent scattering of 661.6 keV gamma rays in a wide range of atomic numbers was studied for 6C, 13Al, 26Fe, 29Cu, 47Ag, 48Cd and 82Pb. It was shown that for heavy elements, the scattering on binding electrons is important. Meanwhile, for light elements, the scattering on free electrons is prominent. The differential Compton scattering cross-section as well as the incoherent scattering ...
-
The double action of Cd2+ in the types and frequencies of chromosomal aberrations induced in human lymphocytes exposed to gamma rays
The presence of agents that prevent repair of DNA breaks caused by irradiation can induce more breaks than not. Cadmium is a factor that may cause DNA damage and also inactivate repair enzymes. This paper describes the investigation of chromosomal aberrations induced in human lymphocytes by the combined action of cadmium and gamma rays. Four groups were investigated: Cd alone, gamma radiation ...
-
Influence of Voids on Density Measurements of Granular Materials Using Gamma Radiation Techniques
The use of gamma radiation equipment for the nondestructive measurement of soil density originated nearly four decades ago. The typical procedure involves a careful calibration of the gamma radiation counts on specimens of known density of the same materials as those whose density are to be measured. This paper presents the results of laboratory gamma-ray density measurements on 100-mm-diameter ...
-
Analysis of gamma ray incoherent scattering for non-destructive testing
An approach for the analysis of gamma ray incoherent scattering on free and binding electrons is presented for Non-destructive Testing (NDT). The method is based on computational simulation and backscattering gamma ray measurements for carbon steel walls. The results of thickness measurements for steel walls are described by the theory of the energy transfer model.Keywords: gamma ray incoherent ...
-
Dose-response of photographic emulsions under gamma irradiation
Photographic emulsion is irradiated under gamma rays irradiation of 137Cs in the IAEA/WHO secondary standard dosimetry laboratory. Dose-response of the film is established. The sensitivity of the film is determined. The dose-rate effect is studied and discussed.Keywords: gamma irradiation, photographic emulsions, dose response, energy transfer model, low ...
-
Radioactive Clean-up
Radioactive, nuclear, or radiation clean-up is considered as the most dangerous, difficult, and costly remediation activity after a nuclear disaster or accident. The contamination may be found in the air, water, and soil, as wells as equipment and buildings (USEPA, 2010). Radioactive material is unstable, while the nuclei of radioactive atoms emit ionizing radiation (i.e., alpha particles, ...
-
Study of the effect of post-irradiation with low linear energy transfer on optical and spectral response of CR-39 polymeric material
The optical properties of CR-39 polymer track detectors irradiated with high Linear Energy Transfer (LET) (alpha particles at energies 3.05 MeV and 4.86 MeV) and followed by low LET (gamma ray irradiation at different doses ranging from 0 to 200 kGy) were investigated. The chemical etching was verified for all samples. Also, the optical properties were studied with an Ultraviolet-Visible (UV-VIS) ...
-
Radioactive Clean-up
Radioactive, nuclear, or radiation clean-up is considered the most dangerous, difficult, and costly remediation activity after a nuclear disaster or accident. The contamination may be found in the air, water, and soil, as wells as equipment and buildings (USEPA, 2010).Radioactive material, unlike most matter, is inherently unstable. Over time, the nuclei of radioactive atoms emit what's known as ...
-
Natural radiation level in the environment of Tehri Garhwal, Uttaranchal
The natural radiation levels were measured in about 50 residential houses of Tehri Garhwal, Uttaranchal, using an environmental radiation dosimeter in both the indoor and the outdoor atmosphere. The total gamma ray activity was found to vary from 29.74 µR/h to 41.19 µR/h with a mean of 36.5 µR/h for the indoor environment, whereas for outdoors it varied from 28.76 µR/h to 43.46 µR/h with a mean ...
-
Laser–assisted nuclear photoeffect re–examined
In a recent article of Dadi and Müller the modification of nuclear photoeffect due to intense laser field is discussed. The paper is criticised from the point of view of gauge invariance. The S–matrix element and the cross–section of the laser–assisted nuclear photoeffect are recalculated in a gauge invariant manner taking into account the effect of the Coulomb field of the remainder nucleus. The ...
-
Experimental determination of dose uniformity in the CDTN gamma irradiator
This paper describes an experimental study of dose uniformity within a container used for products irradiation, in the gamma irradiation facility at Nuclear Technology Development Center (CDTN). The CDTN is a research institute of the National Nuclear Energy Commission (CNEN), Brazil. Polymethylmethacrylate (PMMA) dosimeters were used in order to determine the Dose Uniformity Ratio (DUR) inside ...
-
The nanoparticles of BaSO4:Eu as detectors for high doses of different ionising radiations
Nanoparticles of a BaSO4:Eu phosphor with a particle size of around 40 nm have been irradiated by 48 MeV 7Li3+, 75 MeV C6+ and 90 MeV O7+ ion beams at the fluence range of 1 ∼ l09–1 ∼ 1013 ions/cm2. The thermoluminescence (TL) glow curves of the irradiated samples were recorded and studied. The microcrystalline form of this sample is included in the study with the aim of reporting a comparative ...
-
Study of the effect of post-irradiation with low linear energy transfer on optical and spectral response of CR-39 polymeric material
The optical properties of CR-39 polymer track detectors irradiated with high Linear Energy Transfer (LET) (alpha particles at energies 3.05 MeV and 4.86 MeV) and followed by low LET (gamma ray irradiation at different doses ranging from 0 to 200 kGy) were investigated. The chemical etching was verified for all samples. Also, the optical properties were studied with an Ultraviolet-Visible (UV-VIS) ...
-
Determination of uranium concentration in surface soil samples of Iran
The use of uranium-tipped antitank shells during the Iraq war (2003) caused serious concerns in Iran and the international media over possible contamination of the Iranian environment and consequent long-term health effects. After a shell explosion, uranium is discharged by fire into the air in the form of oxidised particles, which can be dispersed over a radius of several kilometres. Gamma ray ...
-
Survey of natural and artificial radioactivity in Tunisian soils
A study of the natural radioactivity and artificial radioactivity of soils due to gamma ray emitters was performed in Tunisia, as part of the national programme for environment surveillance. Seventeen sites were studied. The determination of radionuclide specific concentrations in the soil samples (0–5 cm) by gamma ray spectrometry showed the following ranges: 40K (93–319 Bq/kg), 226Ra (5–50 ...
-
Characterization of modified PVDF membrane by gamma irradiation for non-potable water reuse
Poly(vinylidene fluorine) (PVDF) membranes were grafted by gamma-ray irradiation and were sulfonated by sodium sulfite to modify the surface of the membranes. The characteristics of the modified PVDF membranes were evaluated by the data of Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscope (FE-SEM), the contact angle of the ...
-
Effect of low doses and low dose-rates of gamma radiation on DNA damage in human peripheral blood leukocytes using comet assay
Comet assay is a sensitive technique and it provides a unique opportunity to investigate intercellular differences in DNA damage and repair in any eukaryotic cell population. This assay can be used to detect DNA single strand breaks, alkali-labile sites and incomplete DNA repair sites, under alkaline conditions and DNA double strand breaks under neutral condition. We report here our observations ...
-
Estimation of
238U,232Th and40K concentrations in rock and soil samples around SouThe first few measurements for low level gamma ray spectrometry for the delineation of U and Th along South Purulia Shear Zone (SPSZ) are reported. Estimation of 238U, 232Th and 40K concentrations in widely dispersed rock and soil samples around SPSZ has been undertaken using HPGe detector having relative efficiency of 50%. The maximum concentration among all the samples studied is observed in ...
Need help finding the right suppliers? Try XPRT Sourcing. Let the XPRTs do the work for you