Solution of Evolution Equation for Longitudinal Structure Function F L upto Next-to-Next-to-Leading Order and Its t-Evolution at Small-x

The aim of the present paper is to calculate longitudinal structure function F _L from QCD (Quantum Chromodynamics) evolution equation in next-to-next-to-leading order (NNLO) at small-x. The calculation of F _L is important for the phenomenological study of gluon distribution function inside the nucleon. Here we use Taylor Series Expansion method to solve the evolution equation for small-x and thus obtain t-evolution of F _L structure function. The calculated results are compared with H1 and ZEUS data and results of Block and Donnachie-Landshoff (DL) models.     

Ag2CO3-catalyzed cycloaddition of organic azides onto terminal alkynes: A green and sustainable protocol accelerated by aqueous micelles of CPyCl

Using catalytic amount of Ag₂CO₃ a simple, efficient and copper free green protocol has been developed to synthesize 1,4-disubstituted 1,2,3-triazoles regioselectively. Here, the cationic surfactant, cetylpyridinium chloride (CPyCl) in water provides a micellar media and accelerates the subsequent Ag(I)-catalysed azide-alkyne cycloaddition (AgAAC) reaction by increasing the concentration of reactants in the micellar pseudophase. Our method is found to be environmentally friendly from E-factor measurement. The surfactant, CPyCl is found to be nontoxic.     

Studies on Squalene Biosynthesis and the Standardization of Its Extraction Methodology from Saccharomyces cerevisiae

Applied Biochemistry and Biotechnology - In this study, a homogenization-based extraction method was developed and was compared to five conventional methods of squalene extraction. Squalene...     

Development of Materials for Blue Organic Light Emitting Devices

The success of organic light emitting diodes (OLED) has been witnessed by the commercialization of this technology for manufacturing the vivid and colorful displays used in our daily life now. The prospective growth of OLED technology on display industry will be optimistic. Over the last three decades, many different approaches on material and device designs have been implemented for improving the efficiency and stability of OLED devices. These efforts install main cornerstones to support the great achievement of OLED technology. However, until now, the performance and stability of blue OLEDs still have some concerns. This troublesome issue should be totally conquered before the large‐scale manufactures dominated over other display technologies, particularly liquid crystal‐based displays, takes place. Though significant progress has already been made to achieve high performance and long lifetime blue OLEDs, this topic still remains as one of the hot researches in OLEDs. We have been working on this area for about two decades and made some notable contributions. Consequently, in this personal account we have outlined our efforts to obtain better performing blue OLEDs by utilizing a range of emitters based on fluorescence, phosphorescence, delayed fluorescence and exciplex systems. We have also developed some novel host materials for blue OLEDs, which are worth mentioning in this account.     

Electronic structure, phonons, and dielectric anomaly in ferromagnetic insulating double pervoskite La2NiMnO6

Using first-principles density functional calculations, we study the electronic and magnetic properties of the ferromagnetic insulating double perovskite compound La2NiMnO6, which has been reported to exhibit an interesting magnetic field sensitive dielectric anomaly as a function of temperature. Our study reveals the existence of very soft infrared active phonons that couple strongly with spins at the Ni and Mn sites through modification of the superexchange interaction. We suggest that these modes are the origin for the observed dielectric anomaly in La2NiMnO6.     

Chirality-induced dynamic kohn anomalies in graphene

We develop a theory for the renormalization of the phonon energy dispersion in graphene due to the combined effects of both Coulomb and electron-phonon (e-ph) interactions. We obtain the renormalized phonon energy spectrum by an exact analytic derivation of the phonon self-energy, finding three distinct Kohn anomalies (KAs) at the phonon wave vector q=omega/v, 2k_{F}+/-omega/v for LO phonons and one at q=omega/v for TO phonons. The presence of these new KAs in graphene, in contrast to the usual KA q=2k_{F} in ordinary metals, originates from the dynamical screening of e-ph interaction (with a concomitant breakdown of the Born-Oppenheimer approximation) and the peculiar chirality of the graphene e-ph coupling.     

Density matrix renormalization group study of incompressible fractional quantum Hall states

We develop the density-matrix renormalization group (DMRG) technique for numerically studying incompressible fractional quantum Hall (FQH) states on the sphere. We calculate accurate estimates for ground-state energies and excitation gaps at FQH filling fractions nu=1/3 and nu=5/2 for systems that are considerably larger than the largest ever studied by exact diagonalization. We establish, by carefully comparing with existing numerical results on smaller systems, that DMRG is a highly effective numerical tool for studying incompressible FQH states.     

Ground state of graphene in the presence of random charged impurities

We calculate the carrier-density-dependent ground-state properties of graphene in the presence of random charged impurities in the substrate taking into account disorder and interaction effects nonperturbatively on an equal footing in a self-consistent theoretical formalism. We provide detailed quantitative results on the dependence of the disorder-induced spatially inhomogeneous two-dimensional carrier density distribution on the external gate bias, the impurity density, and the impurity location. We find that the interplay between disorder and interaction is strong, particularly at lower impurity densities. We show that, for the currently available typical graphene samples, inhomogeneity dominates graphene physics at low (< or approximately 10(12) cm(-2)) carrier density with the density fluctuations becoming larger than the average density.     

Testable signatures of quantum nonlocality in a two-dimensional chiral p-wave superconductor

A class of topological excitations-the odd-winding number vortices-in a spinless 2D chiral p-wave (px+ipy) superconductor traps Majorana fermion states in the vortex cores. For a dilute gas of such vortices, the lowest energy fermionic eigenstates are intrinsically nonlocal. We predict two testable signatures of this unusual quantum nonlocality in quasiparticle tunneling experiments. We discuss why the associated teleportationlike phenomenon does not imply the violation of causality.     

Effect of Ti4+ substitution on the hyperfine properties of Li–Sb–Ti ferrites using Mössbauer spectroscopy

Mössbauer investigations were carried out at room temperature on the ferrite system Li_0.6?+?0.5tFe_2.3???1.5tTi_tSb_0.1O₄ (0.0 ≤ t ≤ 1.0 in steps of 0.2). The effect of Ti^4?+? concentration on the various hyperfine interactions like Isomer shift, quadrupole splitting and internal magnetic field have been studied. The spectra exhibited well-defined Zeeman sextets at low substitution level, corresponding to the A and B sites. The sample with t = 1.0 showed paramagnetic behaviour. The results obtained have been discussed.