Raman imaging and stress quantification in self‐assembled graphene oxide fiber ‘Latin Letters’

To probe the intrinsic stress distribution in terms of spatial Raman shift (ω) and change in the phonon linewidth (Γ), here we analyze self‐assembled graphene oxide fibers (GOF) ‘Latin letters’ by confocal Raman spectroscopy. The self‐assembly of GOF ‘Latin letters’ has been explained through surface tension, π–π stacking, van der Waals interaction at the air–water interface and by systematic time‐dependent investigation using field emission scanning electron microscopy analysis. Intrinsic residual stress due to structural joints and bending is playing a distinct role affecting the E_2g mode (G band) at and away from the physical interface of GOF segments with broadening of phonon linewidth, indicating prominent phonon softening. Linescan across an interface of the GOF ‘letters’ reveals Raman shift to lower wavenumber in all cases but more so in ‘Z’ fiber exhibiting a broader region. Furthermore, intrinsic stress homogeneity is observed for ‘G’ fiber distributed throughout its curvature with negligible shift corresponding to E_2g mode vibration. This article demonstrates the significance of morphology in stress distribution across the self‐assembled and ‘smart‐integrable’ GOF ‘Latin letters’. Copyright © 2016 John Wiley & Sons, Ltd.     

MRDCI study of the low-lying electronic states of PbSi

Electronic states of the PbSi molecule up to 4 eV have been studied by carrying out ab initio based MRDCI calculations which include relativistic effective core potentials (RECPs) of both the atoms. The use of semicore RECPs of Pb produces better dissociation limits than the full-core one. However, the (3)P(0)-(3)P(1) splitting due to Pb is underestimated by about 4000 cm(-1). At least 25 bound electronic states of the Λ-S symmetry are predicted for PbSi. The computed zero-field-splitting in the ground state is about 544 cm(-1). A strong spin-orbit mixing changes the nature of the potential energy curves of many Ω states. The overall splitting among the spin components of A(3)Π is computed to be 4067 cm(-1). However, the largest spin-orbit splitting is reported for the (3)Δ state. A number of spin-allowed and spin-forbidden transitions are predicted. The partial radiative lifetime for the A(3)Π-X(3)Σ(-) transition is of the order of milliseconds. The computed bond energy in the ground state is 1.68 eV, considering the spin-orbit coupling. The vertical ionization energy for the ionization to the X(4)Σ(-) ground state of PbSi(+) is about 6.93 eV computed at the same level of calculations.     

Isolation and purification of a vertebral hemoglobin,the chicken hemoglobin,and its interaction with copperglutathione complex

Hemoglobin was isolated from chicken blood and purified by biochemical methods.This hemoglobin was allowed to interact with copperglutathione (CuGSH) and the interaction pattern was monitored by spectrophotometric and spectrofluorimetric techniques. The interaction ratio was found to be 1:0.7 in both the cases. The equilibrium constant data suggested associative binding and a fluorimetric study revealed that such association occurred around tryptophan residues of hemoglobin.     

Kinetics and mechanism of oxidation of <Emphasis Type="SmallCaps">l</Emphasis>-cystine by manganese(III) in sulfuric acid medium

The kinetics of oxidation of l-cystine by Mn^III have been studied in sulfuric acid medium at 30 °C. The reaction was followed spectrophotometrically at λmax = 500 nm. The reaction shows first order dependence on both [Mn^III] and [cystine]. It was found that the rate of the reaction decreases with increase of [H⁺] up to a certain point and then remains unchanged. The oxidation product of the reaction was found to be cysteic acid. A plausible mechanism has been proposed to account for the experimental results.     

Decay in presence of a uniform electric field

The decay-rate of an eigenstate into the continuum is calculated in a simple 1-dimensional model, when a small uniform electric field is switched on. It is shown that this rate is very sensitive to changes in the field strength, in conformity with experimental observations.Supported by the Fonds National Suisse.     

Exponents of class groups of real quadratic function fields (II)

Let be an even positive integer. We show that there are polynomials with such that the ideal class group of the real quadratic extensions have an element of order .

     

A quantum stochastic Lie-Trotter product formula

A Trotter product formula is established for unitary quantum stochastic processes governed by quantum stochastic differential equations with constant bounded coefficients.