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In this work, the target of zirconia with 2-inch diameter is prepared from the powder form having a particle size 5 µm by giving 4 tonnes of pressure in the hydraulic press. The prepared target is sintered at 1000-degree Celsius for 10 hrs. Yttria-stabilized zirconia target is also obtained in a similar process. The structural properties of both targets are investigated using Ɵ-2Ɵ geometry of X-ray diffractometer system. The changes in structure are studied in doped and undoped zirconia. The structural findings are showing the transformation of phase with doping. These studies help to understand the structural properties of zirconia with and without doping for technological application.

L III jump ratio, jump factor and its related parameters for Pt and Tl have been measured by using photons of energy 59.54 keV from 241 Am source. The measurements are made by using gamma attenuation method in secondary excitation geometry with high resolution (155 eV at 5.9 keV) Si(Li) detector. X-rays energies, above and below the L III edge for the targets of Pt and Tl are obtained by using secondary target of Br, Co, Cu, Fe, Ga, Ni, Pt, Se, Sr, Tl and Zn. The measurements are compared with the theoretical values of total attenuation cross-sections, L III Jump ratio, jump factor; Davisson–Krichner ratio and L III sub-shell oscillator strength obtained by using mass attenuation coefficients from WinXCom. It is observed that the measured values are in good agreement with theoretical results. These measurement shall enhances the understanding of material characteristics of Pt and Tl, as these are widely used in biological, chemical, medical, electronics and petroleum industry.

Effect of chemical environment on the K shell absorption edge parameters i.e. jump factor ( J K ), jump ratio ( r K ) and number of protons in terms of effective atomic number ( Z eff ) has been measured from the study of interaction of photons with pure elements (Zn, Zr, Cd, Ba, Pb) and their compounds [Zn(CH 3 COO) 2 , ZnSO 4 , ZnCl 2 , ZnO, Zr(OH) 4 , ZrN, ZrO 2 , ZrOCl 2 , CdCl 2 , CdCO 3 , Cd(NO 3 ) 2 , Cd(OH) 2 , BaSO 4 , BaCl 2 , Ba(NO 3 ) 2 , BaCO 3 , BaCl 2 ⋅2H 2 O, PbCl 2 , PbO, PbCO 3 , Pb(NO 3 ) 2 , Pb 3 O 4 , Pb(CH 3 COO) 2 ⋅3H 2 O] using Si(Li) detector and EDXRF technique. 59.54-keV gamma ray photons from 241 Am radioactive source have been used for the measurement of K shell absorption edge parameters J K , r K and Z eff . Different values of J K , r K and Z eff have been measured for the same element with different ligands group in the given elemental compounds. All measured results were compared with theoretically calculated values from WinXCOM (Gerward et al., 2001). It is found that measured values are in agreement with the theoretical values within experimental uncertainties of 6%. It is observed that the J K , r K and Z eff are affected in the different chemical environment due to presence of ligand group attached with element. Maximum change in the values of J K , r K and Z eff are observed in case of compounds containing –Cl 2 & –(CH 3 COO) 2 as a ligand group. Further, maximum variation of >20% in the Z eff for Zn and Pb compounds is also observed. From the present measurements, it is found that the J K , r K and Z eff depend on the chemical environment of the compound under investigation. These parameters may be helpful to understand the physical behavior and chemical structure of the compounds.

The linear and mass attenuation coefficient of non-uniform thick samples of oxides of lanthanide (Pr6O11, Nd2O3, Gd2O3, Tb4O7, Ho2O3 and Er2O3) has been measured by gamma ray photons of energy 59.54 keV obtained from 100 mCi radioactive source of 241Am. Advanced Two Media (ATM) methods Gupta et al. (2013) is simplified by considering air as first medium and metallic foil as second medium. In the present measurements this consideration simplifies the mathematical complexities and laboratory work to find the attenuation coefficients of non-uniform thick samples. The values of attenuation coefficient were then used to calculate effective atomic numbers (Zeff), interaction cross-section (σ) and effective electron densities (Neff) of lanthanide oxides. The method is validated by measuring linear/mass attenuation coefficient and other parameters for Mo, Ag, Sn, W and Pb of uniform thickness. The measured results are compared with the theoretical values from WinXcom Gerward et al. (2001). It is found that measured values are in agreement within 2% of theoretical results. The measurement of linear attenuation coefficient, effective atomic numbers (Zeff), interaction cross-section and effective electron densities (Neff) enhances the understanding of material characteristics. Presently studied materials i.e. oxides of Lanthanide are widely used as glass colouring agent and in electronic sensing devices.

We have electrochemically synthesized polyaniline nano fibers with optimized process parameters (viz. concentration of monomer and dopant, applied current density, deposition time, etc.) on ITO coated glass substrate. The nano fibers of polyaniline were subjected to UV Visible, SEM and Raman spectroscopy. UV Vis spectra show two prominent peaks at 317 and 418 nm, which confirm the presence of different forms of polyaniline. Raman spectra confirm the formation of polyaniline. SEM image of synthesized nano fibers showed a flower like structure with an isotropic growth rate. Copyright © 2012 VBRI press.

The internal bremsstrahlung spectra accompanying the nonunique first forbidden beta decay of 170Tm and unique first forbidden beta decay of 89Sr have been measured using an extrapolation procedure with the beta stopper method. In order to avoid errors in the source strength measurement and uncertainty of the normalization procedure, the experimental and the theoretical results are compared in terms of the number of photons of energy k per unit energy interval per unit photon yield. The results for 170Tm show better agreement with the Lewis-Ford theory, particularly in the lower and mid-energy regions, than the Knipp-Uhlenbeck-Bloch (KUB) and Nilsson theories. However the experimental results are higher than those of these theories at the high-energy end. For 89Sr, the experimental results are in agreement with the Lewis-Ford theory in the whole energy region covered by the present measurements and do not favour the KUB and Nilsson theories beyond a photon energy of 400 keV.

Total bremsstrahlung spectra in thick targets of Mo and Pt, produced by beta emitter 89 Sr (end point energy = 1464 keV) have been studied in the photon energy range of 1-100 keV. The experimentally measured spectra measured were compared with the theoretical spectral distributions calculated from Elwert corrected (non relativistic) Bethe-Heitler [EBH] theory, modified Elwert factor (relativistic) Bethe-Heitler (F mod BH) theory for ordinary bremsstrahlung (OB) and the modified Elwert factor (relativistic) Bethe-Heitler (F mod BH+PB) theory, which includes the polarization bremsstrahlung (PB) into total bremsstrahlung (BS). The present results indicate the correctness of F mod BH+PB theory in the low energy region, where the contributions of PB into BS are dominant. But at the middle and higher energy region of the bremsstrahlung spectrum, where the contribution of PB is negligible, the F mod BH theory is more close to the experimental results.