Explaining GRB in the light of energy deposition rate for v+ [`(n)] \bar \nu → e+ + e? in a compact star

We have studied the v+ $ \bar \nu $ \bar \nu → e ⁺ + e ⁻ energy deposition rate near a rotating compact star which is important for the study of gamma ray bursts (GRB). The General relativistic (GR) and rotational effects increase the efficiency of the process immensely. The rotational effect also brings about an asymmetry in the deposition rate of the star.     

In situ formation of magnetic–luminescent, bi-functional, polymer-stabilized cerium sulfide nanoparticles

Polymer-stabilized paramagnetic and fluorescent rare-earth metal sulfide (cerium sulfide, Ce₂S₃) nanoparticles have been synthesized by using an ??in situ polymerization and composite formation?? (IPCF) technique (Mallick et al. in J. Appl. Phys. 106:074303, 2009) at room temperature. Encapsulated cerium sulfide nanoparticles showed photoluminescence when excited with laser irradiation. The composite material exhibited a paramagnetic behavior due to the in situ formation of magnetic Ce³⁺ ionic species at the reaction condition.     

Quantum Fluctuation Relations for the Lindblad Master Equation

An open quantum system interacting with its environment can be modeled under suitable assumptions as a Markov process, described by a Lindblad master equation. In this work, we derive a general set of fluctuation relations for systems governed by a Lindblad equation. These identities provide quantum versions of Jarzynski-Hatano-Sasa and Crooks relations. In the linear response regime, these fluctuation relations yield a fluctuation-dissipation theorem (FDT) valid for a stationary state arbitrarily far from equilibrium. For a closed system, this FDT reduces to the celebrated Callen-Welton-Kubo formula.     

Adsorption of hexavalent chromium on manganese nodule leached residue obtained from NH3-SO2 leaching

Adsorption of hexavalent chromium onto manganese nodule leached residues was investigated as a possible alternative to the conventional methods of its removal from aqueous synthetic solutions. Adsorption behavior was studied as a function of time, pH, temperature, and concentration of adsorbate and adsorbent in acetic acid-sodium acetate buffer medium. Cr (VI) removal was pH dependent and was found to be of a maximum at pH 3. The applicability of the Langmuir isotherm to the present system was tested. Increased adsorption capacity with increased temperature indicates that the adsorption reaction was endothermic in nature. Based on these studies, thermodynamic parameters such as Gibbs free energy change (DeltaG0), standard enthalpy change (DeltaH0), and standard entropy change (DeltaS0) were calculated.     

Surfactant-induced modulation of fluorosensor activity: a simple way to maximize the sensor efficiency

Tuning of the sensory capability of a potentially bioactive indoloquinolizine system, namely, 3-acetyl-4-oxo-6,7-dihydro-12H-indolo-[2,3-a]-quinolizine (AODIQ), is described in a biomimicking micellar nanocage. It has been shown that surfactant concentration dictates the sensing behavior of the fluorophore toward physiologically essential trace metals, such as Cu2+. This is a simple, efficient, and general technique that allows one to utilize the sensor to its maximum efficiency.     

Kinetics and mechanism of the ligand substitution reaction of di-μ-hydroxobis(bipyridyl)dipalladium(II) ion with thiourea in aqueous solution

The kinetics of the interaction between thiourea and the title complex has been studied spectrophotometrically in aqueous medium as a function of nucleophile concentration, temperature and pH at constant ionic strength. The reaction is a two-step process in which the first step is ligand dependent, but the second step is ligand independent and is assigned to ring closure. The rate and activation parameters, conductivity studies and IR data were used to deduce a plausible mechanism.     

Redox catalytic property of gold nanoclusters: evidence of an electron-relay effect

The objective of this study is to investigate the elementary mechanism of the formation of nanoclusters in terms of the various stages involved, viz. atom formation, cluster nucleation and growth. The thermodynamics of their reaction where the clusters play an efficient role as a catalyst for the redox system is also another interesting dimension of the study. Synthesis of particles suggests a two-step process, i.e. nucleation and successive growth. The atoms agglomerate to form metal clusters. A metal cluster acting as a catalytic relay behaves alternately as an acceptor and as a donor of electrons. An effective transfer of electrons is possible when the potential of the cluster is more positive than that of the electron-donor system. PACS 87.20.Dd; 81.16.Hc; 81.07.-b; 78.67.-n; 82.35.Np     

Additive Positive Stable Frailty Models

In this article, we describe an additive stable frailty model for multivariate times to events data using a flexible baseline hazard, and assuming that the frailty component for each individual is described by additive functions of independent positive stable random variables with possibly different stability indices. Dependence properties of this frailty model are investigated. To carry out inference, the likelihood function is derived by replacing high-dimensional integration by Monte Carlo simulation. Markov chain Monte Carlo algorithms enable estimation and model checking in the Bayesian framework.