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We have studied the X-ray and gamma radiation shielding parameters such as mass attenuation coefficient, linear attenuation coefficient, Half Value Layer (HVL), Tenth Value Layer (TVL), effective atomic number and electron density in some boron polymers of different boron based polymers [ Polymer A-PolyBorazylene (B3N3H4), Polymer B- 4-Vinylphenyl Boronic acid (C8H9O2B), Polymer C- Borazine (B3N3H6), Polymer D- 3-Acrylamidophenylboronic acid (C9H10BNO3) Polymer E-Phenylethenylboronic acid (C14H19BO2), Polymer F- 4-Aminophenylboronic acid (C12H18BNO2) and Polymer G- 3- Aminophenylboronic acid (C6H8BNO2)]. We have also studied the neutron shielding properties such as coherent neutron scattering length, incoherent neutron scattering lengths, coherent neutron scattering cross section, incoherent neutron scattering cross sections, total neutron scattering cross section and neutron absorption cross sections in the boron polymers. We have compared the shielding properties among the studied different boron polymers. From the detail study, it is clear that the boron polymer Phenylethenylboronic acid is good absorber for X-ray, gamma radiation and neutron. Hence, we suggest that the boron polymer Phenylethenylboronic acid is good shielding material for X-ray, gamma and neutrons. [ABSTRACT FROM AUTHOR]

In the present work, we have considered the total potential as the sum of the coulomb and proximity potential. We have used the recent proximity function to calculate the nuclear potential. The calculated logarithmic half-lives correspond to fission, cluster and alpha decay are compared with that of experiments. We also identified the most probable decay mode by studying branching ratios of these different decay modes. The competition between different decay modes such as fission, cluster radioactivity and alpha decay finds an important role in nuclear structure. [ABSTRACT FROM AUTHOR]

The nature of hydroxylamine complexes was identified through the formation of hydrogen bonding between alcohols (methanol, ethanol, propanol, and butanol) with aniline from the dielectric measurements like dielectric constant, density and refractive index. From these measurements, the dipole moment of hydroxylamine complex was determined from the Huysken's method origin of Onsager model also evaluated the dipolar increment. The enthalpy changes due to bond formation obtained from the dipolar increment. The dipole moment of the both cis and trans structure are determined and tabulated, the dipole moment values of the trans are higher than the cis structure it may complex is form the trans structure. The value of dipole moment of the complex, dipolar increment and enthalpy changes concluded complex formation mainly due to the polarization only. These values indicate the order of the complex methanol > ethanol > propanol > butanol, aniline as one of the component. [ABSTRACT FROM AUTHOR]

The ultrasonic velocity, density and viscosity values of liquid mixture of aqueous polyvinyl pyrrolidone with aqueous zinc sulphate, manganese sulphate, zinc chloride and manganese chloride have been studied at 303.15 K, 308.15 K and 313.15 K. Relative association, surface tension, modified surface tension, adiabatic compressibility, acoustic impedance, intermolecular free length relaxation time and the nonlinearity parameter have been determined for various compositions. The variation observed in the results suggest that the presence of strong polymer-solvent interactions. [ABSTRACT FROM AUTHOR]

Electrodeposited alloy thin films Ni-Fe-S were prepared at temperatures 30, 50, 70 and 90°C. Electrodeposited Ni-Fe- S thin films were subjected to morphological, structural, magnetic and mechanical characterization analysis. The chemical composition of the coated films was analyzed by EDAX and result shows that nickel content increases when bath temperature is increased. The surface and structural morphology of the coated film were analyzed by using SEM and XRD. The results show that thin films are bright, crack free and uniform. The mechanical characterization of Ni- Fe-S thin films have been analyzed by VHT and result shows that hardness increases when bath temperature is increased. The electroplated Ni-Fe-S thin films were strongly adherent to the copper substrate. All the electrodeposited Ni-Fe-S films exhibit FCC crystalline structure by XRD study.The VSM result of Ni-Fe-S thin films shows that thin films coated at high bath temperature have highest saturation magnetization value. [ABSTRACT FROM AUTHOR]

Nickel and manganese (Ni–Mn) co-doped with tin oxide (Sn(2–(x + y))NixMnyO2) nanoparticles were synthesised by a sol-gel method. The influence of dopant concentration on prepared samples is investigated by different analytical techniques including X-ray diffraction (XRD), vibrating sample magnetometer, diffuse reflectance spectra, scanning electron microscope (SEM) and transmission electron microscope (TEM) to study the structural, optical and magnetic properties. The XRD study reveals that the formation of single-phase rutile tetragonal structure of all the samples and also the particle size vary from 8 to 6.5nm. The lattice constant and crystallite size are decreased as the (Ni–Mn) codoped with SnO2and found to decrease with increasing doping concentrations. Magnetic measurements show that the (Ni–Mn)-doped SnO2exhibit room temperature ferromagnetism. SEM and TEM are used to study the external morphology and particle size of the prepared sample. [ABSTRACT FROM AUTHOR]

Red light emitting cubic Zr0.99Eu0.01O2:Li+ (0–9 mol%) nanoparticles are synthesized by a low temperature, self-propagating solution combustion method using oxalyl di-hydrazide (ODH) as fuel. In this study, we report systematic investigation of the effect of lithium ion (Li+) concentration on the structural properties and the photoluminescence of zirconia. With increasing lithium concentration, the crystallinity of the samples increases and the lattice strain decreases. The higher crystallinity is likely due to charge compensation achieved by replacing one Zr4+ ion by a Eu3+ and a Li+ ion. Scanning electron micrographs (SEM) reveal a mesoporous structure characteristic of combustion derived nanomaterials. Photoluminescence (PL) spectra show that the intensity of the red emission (606 nm) is highly dependent on Li+ ion concentration. Furthermore there is a promising enhancement in the associated lifetime. Upon Li+ doping, the PL intensity of the samples is found to increase by two fold compared to the undoped sample. Variation of PL intensity with Li+ concentration is attributed to the differences in probability of non-radiative recombination (relaxing). Intensity parameters (Ω2, Ω) and radiative properties such as transition rates (A), branching ratios (β), stimulated emission cross-section (σe), gain bandwidth (σe×Δλeff) and optical gain (σe×τ) are calculated using the Judd–Ofelt theory. The calculated values suggest that in optimally co-doped samples, in addition to improved crystallinity and charge compensation, the lowering of Eu3+ site symmetry and the increase in the covalency of Eu–O bonding due to interstitial Li are responsible for the observed enhancement in PL intensity. [ABSTRACT FROM AUTHOR]

We have synthesized undoped and Sm3+ ions doped ZrO2 nanophosphors by solution combustion method. These nanophosphors crystallized in cubic structure. Rietveld refinement of the samples was performed to estimate lattice parameters. Spherical particles with the sizes of 10-25 nm were observed by transmission electron microscopy. Photoluminescence and thermoluminescence (TL) properties of samples were investigated. Under 400 nm excitation, the nanophosphors have intense red emission at 600 nm. The color coordinates (0.67, 0.33) were located in the red region of CIE diagram. TL properties of nanophosphors were studied by exposing the samples to γ-rays. 5 mol% Sm3+ doped ZrO2 nanophosphor has shown maximum TL intensity after γ-irradiation. To test suitability of the nanophosphors for practical application in dosimetry, the 5 mol% Sm3+ doped ZrO2 sample was irradiated by 14 MeV electron beam in various electron fluence ranging from 100 to 900 Gy and their TL response was recorded. [ABSTRACT FROM AUTHOR]

Red light emitting cubic Zr 0.99 Eu 0.01 O 2 :Li + (0-9 mol%) nanoparticles are synthesized by a low temperature, self-propagating solution combustion method using oxalyl di-hydrazide (ODH) as fuel. In this study, we report systematic investigation of the effect of lithium ion (Li + ) concentration on the structural properties and the photoluminescence of zirconia. With increasing lithium concentration, the crystallinity of the samples increases and the lattice strain decreases. The higher crystallinity is likely due to charge compensation achieved by replacing one Zr 4+ ion by a Eu 3+ and a Li + ion. Scanning electron micrographs (SEM) reveal a mesoporous structure characteristic of combustion derived nanomaterials. Photoluminescence (PL) spectra show that the intensity of the red emission (606 nm) is highly dependent on Li + ion concentration. Furthermore there is a promising enhancement in the associated lifetime. Upon Li + doping, the PL intensity of the samples is found to increase by two fold compared to the undoped sample. Variation of PL intensity with Li + concentration is attributed to the differences in probability of non-radiative recombination (relaxing). Intensity parameters (Ω 2 , Ω) and radiative properties such as transition rates (A), branching ratios (β), stimulated emission cross-section (σ e ), gain bandwidth (σ e × Δλ eff ) and optical gain (σ e × τ) are calculated using the Judd-Ofelt theory. The calculated values suggest that in optimally co-doped samples, in addition to improved crystallinity and charge compensation, the lowering of Eu 3+ site symmetry and the increase in the covalency of Eu-O bonding due to interstitial Li are responsible for the observed enhancement in PL intensity.

Pure cubic zirconia (ZrO2) nanopowder is prepared for the first time by simple low temperature solution combustion method without calcination. The product is characterized by Powder X-ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infra Red spectroscopy (FTIR) and Ultraviolet-Visible spectroscopy (UV-Vis). The PXRD showed the formation of pure stable cubic ZrO2 nanopowders with average crystallite size ranging from 6 to 12 nm. The lattice parameters were calculated from Rietveld refinement method. SEM micrograph shows fluffy, mesoporous, agglomerated particles with large number of voids. TEM micrograph shows honey comb like arrangement of particles with particle size ∼10 nm. The PL emission spectrum excited at 210 nm and 240 nm consists of intense bands centered at ∼365 and ∼390 nm. Both the samples show shoulder peak at ∼420 nm, along with four weak emission bands at ∼484, ∼528, ∼614 and ∼726 nm. TL studies were carried out pre-irradiating samples with γ-rays ranging from 1 to 5 KGy at room temperature. A well resolved glow peak at 377 °C is recorded which can be ascribed to deep traps. With increase in γ radiation there is linear increase in TL intensity which shows the possible use of ZrO2 as dosimetric material., (Copyright © 2013 Elsevier B.V. All rights reserved.)