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Aluminum oxide nanoparticles were incorporated into polystyrene using solution casting method. The films so obtained were irradiated with gamma rays using 60Co source. The radiation induced luminescence properties of the polymeric films were studied using UV-visible and photoluminescence spectroscopies. UV-Visible studies reveal enhancement of band gap upon gamma irradiation which could be ascribed to increased defects in the polymer matrix. The photoluminescence spectra of PS/Al2O3 show broad peaks around 410, 435 and 461 nm with the excitation wavelength of 380 nm. The peak height isfound to diminish with increasing radiation dose. PL spectra show significant shifting of the highest intensity position due to gamma radiation. [ABSTRACT FROM AUTHOR]

The pressure and temperature dependent mechanical properties as Young modulus, Thermal expansion coefficient of rare earth REX (RE = La, Pr, Eu; X = O, S, Se, and Te) chalcogenides are studied. The rare earth chalcogenides showed a structural phase transition (B1-B2). Pressure dependence of Young modulus discerns an increase in pressure inferring the hardening or stiffening of the lattice as a consequence of bond compression and bond strengthening. Suppressed Young modulus as functions of temperature infers the weakening of the lattice results in bond weakening in REX. Thermal expansion coefficient demonstrates that REX (RE = La, Pr, Eu; X = O, S, Se, and Te) chalcogenides is mechanically stiffened, and thermally softened on applied pressure and temperature. [ABSTRACT FROM AUTHOR]

The pressure and temperature dependent volume collapse, second order Cauchy discrepancy, anisotropy, melting temperature, hardness, heat capacity and thermal expansion coefficient of SmX; (X = O, S, Se, Te) chalcogenides are studied. Pressure dependence of melting temperature (Tm) discerns an increase inferring the hardening or stiffening of the lattice as a consequence of bond compression and bond strengthening. Suppressed TM as functions of temperature infers the weakening of the lattice results in bond weakening in SmX; (X = O, S, Se, Te) chalcogenides. Vickers Hardness (HV), heat capacity and thermal expansion coefficient of SmX; (X = O, S, Se, Te) chalcogenides demonstrates that SmX is mechanically stiffened, thermally softened and brittle on applied pressure and temperature. [ABSTRACT FROM AUTHOR]

As CMOS technology scales nano-metrically, reliability turns out to be a decisive subject in the design methodology of nano-sized circuit systems. As a result, several computational approaches have been developed to compute and evaluate reliability of desired nano-electronic circuits. The process of computing reliability becomes very troublesome and time consuming as the computational complexity build ups with the desired circuit size. Therefore, being able to measure reliability instantly and superiorly is fast becoming necessary in designing modern logic integrated circuits. For this purpose, the paper firstly looks into the development of an automated reliability evaluation tool based on the generalization of Probabilistic Gate Model (PGM) and Boolean Difference-based Error Calculator (BDEC) models. The Matlab-based tool allows users to significantly speed-up the task of reliability analysis for very large number of nano-electronic circuits. Secondly, by using the developed automated tool, the paper explores into a comparative study involving reliability computation and evaluation by PGM and, BDEC models for different implementations of same functionality circuits. Based on the reliability analysis, BDEC gives exact and transparent reliability measures, but as the complexity of the same functionality circuits with respect to gate error increases, reliability measure by BDEC tends to be lower than the reliability measure by PGM. The lesser reliability measure by BDEC is well explained in this paper using distribution of different signal input patterns overtime for same functionality circuits. Simulation results conclude that the reliability measure by BDEC depends not only on faulty gates but it also depends on circuit topology, probability of input signals being one or zero and also probability of error on signal lines. [ABSTRACT FROM AUTHOR]

The level structures in 98,99Rh, and 99Pd nuclei have been investigated through in beam γ-ray spectroscopic techniques following the 75As(28Si, xpyn) fusion-evaporation reaction at Elab =120 MeV. These investigations were carried out using Indian-National-Gamma-Array (INGA) consisting of Compton-suppressed clover detectors at the Inter-University Accelerator Centre, New Delhi. The level structures observed in 99Pd, and 98,99Rh have been established up to ~11 MeV, 10 MeV and 16 MeV excitation energy and spin ~ 23ħ,23ħ, and 28ħ respectively. In the doubly-odd 98Rh nucleus, new bandstructures and isomeric states have been identified at lower spins and new states below the previously identified 2+ ground state (T1/2 = 8.5 m) are identified. In the present work 99Rh structure have been observed similar to 101Rh which is based on p1/2 and g9/2 orbitals. Various positive and negative parity states in these nuclei are observed to be energetically more favored with respect to the neighboring ones, and are likely to be the maximally aligned states obtained by angular momentum coupling of the valence particles (holes). The level structures observed in Pd have been interpreted in the framework of a microscopic theorybased on the deformed Hartree-Fock (HF) and angular momentum projection techniques. Bandstructures at low excitation energy are based on the low-Ω vg7/2 and vd5/2 orbitals, have been observed in 99Pd. Band structure at higher spins are reproduced with the v(g7/2)² ⊗ v(g7/2)-1 ⊗ v(h11/2)² ⊗ n(g9/2)6 configurations. Observation of new E1 transitions linking the opposite parity vh11/2 and vd5/2 bands provide fingerprints of possible octupole correlations in 99Pd. The extracted values of the B(E1)/B(E2) ratios for the lower levels in the vh11/2 band are ~ 10-7 [fm]-2. [ABSTRACT FROM AUTHOR]

In the present work excited states in 98,99Rh nuclei were populated in the fusion-evaporation reaction 75As(28Si,xpyn) at Elab = 120MeV. The de-excitations have been investigated through in-beam γ-ray spectroscopic techniques. The present level scheme of 98Rh and 99Rh has been established up to J ∼ 23h and 29h respectively. In the doubly-odd 98Rh nucleus new band structure and isomeric states have been identified at lower spins. New states below the previously assigned 2+ ground state (T1/2 = 8.5m) are identified. The low lying band structures in 99Rh are based on πp1/2 and πg9/2 quasiparticles which further evolve into high spin structures following (νh11/2)2 alignment. Multifragmentations at the positive and negative parity bands at spins around 20h is observed, which are likely to be maximally spin aligned states similar to the ones observed in 101Rh. [ABSTRACT FROM AUTHOR]

As CMOS transistors reduced in size, the circuit built using these nano-scale transistors naturally becomes less reliable. The reliability reduction, which is the measure of circuit performance, has brought up so many challenges in designing modern logic integrated circuit. Therefore, reliability modeling is increasingly important subject to be considered in designing modern logic integrated circuit. This drives a need to compute reliability measures for nano-scale circuits. This paper looks into the development of reliability automation tool (RAT) for circuit's reliability computation. The tool is developed using Matlab programming language based on the reliability evaluation model called Probabilistic Transfer Matrix (PTM). RAT allows users to significantly speed-up the reliability assessments of nano-scale circuits. Users have to provide circuit's netlist as the input to RAT for its reliability computation. The netlist signifies the circuit's description in terms of Gate Profile Matrix (GPM), Adjacency Computation Matrix (ACM) and Grid Layout Matrix (GLM). GPM, ACM and GLM indicate the types of logic gates, the interconnection between these logic gates and the layout matrix of these logic gates respectively in a given circuit design. Here, the reliability assessment by RAT is carried out on Full Adder circuit as the benchmark test circuit. [ABSTRACT FROM AUTHOR]

A polycrystalline ceramics of (1-x)Ba(Fe0.5Nb0.5)O3-xSrTiO3, with x = 0, 0.05 was synthesized by high temperature solid-state reaction technique. X-ray diffraction analysis of the powders suggests the formation of a single-phase material with monoclinic structure. SEM images exhibit the uniform distribution of grains of the sample. Sintered pellets were investigated for its dielectric ([variant_greek_epsilon][acute_underaccent] and tanδ) properties in the temperature range of 30 °C-270 °C and in the frequency range of 100Hz-5MHz suggest that the compound do not have dielectric anomaly in the studied frequency and temperature ranges. [ABSTRACT FROM AUTHOR]

The present paper reports the study of semiconducting parameters (activation energy and pre-exponential factor) in glassy samples of Se90X10 (X= Ag, In) in dark as well as in presence of light. Temperature dependence of dark and photo-conductivity is measured in amorphous thin films in the temperature range 300-378 K and in the intensity range 2000-18000 Lux. A straight line between lnσ0 and ΔE indicates the presence of Meyer - Neldel (MN) rule in dark as well as in presence of light. Linear dependence of ln(σ0) on ΔE in case of amorphous material indicate that the conduction band tails a finite energy distance towards the valence band and a Fermi level which is controlled by fixed dominant hole levels deeper in the gap. [ABSTRACT FROM AUTHOR]

The high-pressure structural phase transition and pressure as well temperature induced elastic properties in ReY; (Re = La, Sc, Pr; Y = N, P, As, Sb, Bi) pnictides have been performed using effective interionic interaction potential with emphasis on charge transfer interactions and covalent contribution. Estimated values of phase transition pressure and the volume discontinuity in pressure-volume phase diagram indicate the structural phase transition from NaCl to CsCl structure. From the investigations of elastic constants the pressure (temperature) dependent volume collapse/expansion, second order Cauchy discrepancy, anisotropy, hardness and brittle/ductile nature of rare earth pnictides are computed. [ABSTRACT FROM AUTHOR]

The ITER Ion Cyclotron Heating and Current Drive system will deliver 20 MW of radio frequency power to the plasma in quasi continuous operation during the different phases of the experimental programme. The system also has to perform conditioning of the tokamak first wall at low power between main plasma discharges. This broad range of requirements imposes a high flexibility and a high availability. The paper highlights the physics and design requirements on the IC system, the main features of its subsystems, the predicted performance, and the current procurement and installation schedule. [ABSTRACT FROM AUTHOR]

The authors used a sun-tracking multiple wavelength radiometer to study characteristics of atmospheric aerosols from Pune University campus. The study shows that there is a strong influence of weather parameters like relative humidity and surface wind and atmospheric boundary layer processes such as capped inversion and upper air circulation on the temporal variation of the aerosol spectral optical depth. These are described in the paper. [ABSTRACT FROM AUTHOR]

Copper-embedded Polymethylmethacrylate (PMMA) composites were prepared by solution casting method at different copper concentrations. The alternate current (ac) electrical properties of Cu/PMMA composite films have been investigated at different temperatures in the frequency range from 100 Hz to 10 MHz. The electrical conductivity of the composite increased with increasing temperature and it obeys universal power law (i.e. σ=Aωn). The dielectric constant of Cu/PMMA composites increased with increasing temperature, which has been attributed to the segmental mobility of the polymer molecules. [ABSTRACT FROM AUTHOR]