H.S. Sahota

Effective atomic number studies in different soils for total photon interaction in the energy region 10–5000 keV

Abstract Effective atomic numbers (Zeff) of 12 different soil samples were computed for total photon interaction cross sections using theoretical data over a wide energy region from 10 to 5000 keV. It is seen that Zeff of a composite material, like soil, changes with a change in energy. With an increase in energy from 10 to 20 keV, Zeff increases, then remains nearly constant up to 40 keV but decreases sharply from 40 to 400 or 500 keV, and a further comparatively small rate of decrease up to 1500 keV. However, there is a small but continuous increase in Zeff with photon energy increases of 1500–5000 keV. This significant change in Zeff of soil is due to variations in the domination of different interaction processes in different energy regions as well as to the large number of elements present in the soil.

A new method for simultaneous measurement of soil bulk density and water content

Abstract A new idea is given for the dual-energy method of measuring the soil-water characteristics in which two different energies are taken from a single source. Compared with the previous dual-energy as well as the single-energy methods, this proposed single-source dual-energy method is more accurate and convenient, for the simultaneous measurement of bulk density and water content of soil.

A study of trace elements in scalp hair and fingernails of industrial workers of Ontario, Canada

Instrumental neutron activation analysis was performed on scalp hair and fingernail samples collected randomly from a group of heavily exposed healthy male industrial workers living in the cities of Hamilton and Toronto (Ont.), Canada. The concentrations of trace elements (Ag, Au, Br, Cd, Co, Cr, Cs, Fe, Hg, Lu, Mn, Mo, Rb, Ru and T3) were evaluated and compared for scalp hair and fingernails. Various trace elements show similar variations in the two kinds of samples. The results have also been compared with those for normal subjects from USA (scalp hair) and Canada (fingernails).

The application of energy-dispersive x-ray fluorescence spectrometry (EDXRF) to the analysis of cosmetic evidence in Indian nail polishes

The application of energy-dispersive x-ray fluorescence (EDXRF) spectrometry in the quantitative analysis of samples of Indian nail polishes of apparently similar shades from different manufacturers has been examined by evaluating the possibility of detecting spurious material which is marketed under the guise of a popular brand. On the basis of the number of elements detected, and from the ratios of particular elements [Fe/Ti, Fe/Cu, Ti/Cu] the results are very encouraging.

Decay studies of131Ba

The electron-capture decay of131Ba (T1/2=11.7 d) to excited levels of131Cs has been studied using high resolution semiconductor detectors. The presence of 1046.9 keV gamma-ray in between 1170.6 and 123.8 keV levels, in addition to 1047.6 keV gamma-ray from 1047.6 keV level to ground state of131Cs is confirmed through gamma-gamma coincidence measurements. TheK-capture probabilities to 1047 keV, 696 keV and 620 keV levels are measured usingX-gamma coincidence method. The gamma-gamma directional correlation measurements of the cascades 496-123, 240-133, 486-133, 404-216, 480-216 and 832-216 keV are carried out and spins and multipolarities of the levels and transitions involved are studied.

Study of perturbed angular correlation parameters in bovine serum albumin using 133Ba as a probe.

The gamma-gamma sum peak method has been applied to the measurement of the total attenuation factors G22, in different concentrations of biological material, bovine serum albumin (BSA) using 133Ba as a probe. It is observed that G22 is inversely proportional to the correlation time of the two cascade radiations and to the concentration of biological sample surrounding the probe.

The suitability of 160Tb as a PAC probe for studies of biomolecules

The gamma-ray perturbed angular correlation (PAC) studies were made with 160Tb as a probe in MES (2[N-morpholino]-ethane sulphonic acid) solutions of various concentrations. The measurements indicate no influence of concentration of the environment on its interaction with Tb3+ ion and as such reveal the fact that 160Tb is not a good probe for PAC studies.

K -capture in the decay of 191 PT

Relative K-capture probabilities to three levels of 1911r are determined from the decay of 191 Pt using the sum coincidence method based on summing of gamma rays and K X-rays in a single HPGe detector. The results agree with theoretical values. The electron-capture decay energy calculated using j3-decay properties to different levels belonging to the same rotational family is in agreement with the experimental value.

Measurement of K-electron capture probabilities to the levels of185Re following the EC decay of185Os

K to total capture ratios have been measured explicitly for the first time from the decay of185Os to 880, 874, 717 and 646 keV levels in185Re using the technique of gamma-KX-ray summing in a single intrinsic Ge detector. The results agree with the theoretical values.

Perturbed angular correlation study using147Nd as a probe

The time integral pertturbed angular correlation (TIPAC) technique is employed to study PAC parameters in aqueous solutions of biomolecules Bovine Serum Albumin (BSA), lysozyme and ethylenediaminetetraacetic acid disodium salt (EDTA), using radioactive147Nd as a probe. The attenuation coefficient (G22) is found to decrease with increasing concentration of BSA The effect of attenuation is more pronounced for protein molecules BSA and lysozyme than in the case of EDTA. The relaxation constant (λ2) increases with increasing concentration of the solution as well as with the increasing size of the solute molecule.