Growth of preferential attachment random graphs via continuous-time branching processes

Some growth asymptotics of a version of ‘preferential attachment’ random graphs are studied through an embedding into a continuous-time branching scheme. These results complement and extend previous work in the literature.     

Nonequilibrium fluctuations for a tagged particle in mean-zero one-dimensional zero-range processes

We prove a non-equilibrium functional central limit theorem for the position of a tagged particle in mean-zero one-dimensional zero-range process. The asymptotic behavior of the tagged particle is described by a stochastic differential equation governed by the solution of the hydrodynamic equation.     

<Emphasis Type="Italic">Areca catechu</Emphasis> Assisted Synthesis of Silver Nanoparticles and its Electrocatalytic Activity on Glucose Oxidation

In this work, a facile biogenic route for the synthesis of silver nanoparticles (AgNPs) is reported. The aqueous extract of Areca catechu (A. catechu) nuts are used as reducing source. The synthesized AgNPs characterized by UV–Visible (UV–Vis) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM) with energy dispersive spectrum (EDS) analysis. The formations of AgNPs are identified from the appearance of yellow color and the surface plasmon resonance absorbance peak between 407 and 437 nm. The FT-IR results exposed that the active biomolecules of A. catechu are responsible for capping of AgNPs. The synthesized AgNPs are distorted spherical shape with 45 nm of size, identified from the HR-TEM. In application, the electrocatalytic activity of AgNPs is analyzed towards glucose oxidation using cyclic voltammetry. The results showed that A. catechu derived AgNPs act as good electrocatalyst than bare bulk silver and glassy carbon electrodes.     

Growth and characterization of organic nonlinear optical crystal of 1-chloro-2,4-dinitrobenzene (CDNB)

Organic nonlinear optical crystal of 1-chloro-2,4-dinitrobenzene has been successfully grown by low temperature solution growth technique. Good optical quality single crystals of size 28 mm x 11 mm x 5mm are obtained. Grown crystals were subjected to X-ray powder diffraction analysis, FT-IR, FT-Raman, proton nuclear magnetic resonance (PNMR) and etching studies. Thermal properties of the grown crystals were studied by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA). UV-vis studies show the cutoff wavelength is less than 400 nm. Nonlinear optical property of the crystal was studied by Kurtz powder technique using Nd:YAG laser and the crystal exhibits second harmonic generation property.     

Molecular structure, vibrational spectroscopic, first order hyperpolarizability and HOMO-LUMO studies of 7-amino-8-oxo-3-vinyl-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

The FT-IR and FT-Raman spectra of 7-amino-8-oxo-3-vinyl-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (7AVCA) were recorded in the region 4000-400 cm(-1) and 3500-10 cm(-1), respectively. Quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers were carried out by ab initio HF and density functional theoretical methods invoking 6-311G(d,p) basis set. The differences between the observed and scaled wavenumber values of most of the fundamentals are very small. The electric dipole moment (μ) and the first order hyperpolarizability (β0) values have been computed quantum mechanically. The calculated results show that 7AVCA may have microscopic nonlinear optical (NLO) behavior with non-zero values. A detailed interpretation of the FT-IR and FT-Raman spectra of 7AVCA is reported. The theoretical IR and Raman spectra of 7AVCA have also been constructed. The calculated HOMO and LUMO energies show that the charge transfer occurs within the molecule.     

Conformational isomers from rotation of diacetylenic bond in an ethynylpyrene-substituted molecular hinge

The first example of isolation and X-ray crystallographic structural characterization of two conformers arising from rotation along a diacetylenic bond is reported. In both the conformers extensive pi-pi interactions are observed in the solid state. VT-NMR and fluorescence spectroscopic studies in solution suggest that the closed and open conformers are in equilibrium and that the closed conformer is the predominant species at room temperature.     

Electrically conducting,transparent, graphene based nanocomposite coatings on flexible film substrate

Transparent, electrically conducting nanocomposite coated polyethylene terephthalate (PET) films are prepared using two types of bulk synthesized few layered graphene; namely reduced graphene oxide (rGO) and liquid exfoliated graphite (EG) dispersed in ultra high molecular weight polyethylene (UHMWPE). This study focuses on application of high concentration of such nanofillers (1: 1 to 2.5: 1 ratios with polymer) in order to develop a highly conducting but ultrathin coating for better transparency. The coated PET films are characterized for their surface morphology, electrical and optical properties. High resolution transmission electron microscopic (HRTEM) images and corresponding selected area electron diffraction (SAED) patterns confirm that the graphite has been exfoliated to few layer graphene using both the synthesis routes. Transmittance values of these coated films are measured in UV visible spectrum. The rGO based samples have high transmittance (~90–95%) compared to EG based samples (~40–50%). From current-voltage (I?V) graph and surface resistivity studies, it has been observed that rGO based samples are dielectric in nature similar to UHMWPE while EG based samples are electrically conducting and its conductivity increases with its concentration. EG based nanocomposite coated samples show much better electrical conductivities (resistance 338 to 66 kΩ at different concentrations of EG) than rGO based samples.     

Quantum chromodynamics: Working group report

This is the report of the QCD working group at WHEPP-6. Discussions and work on heavy ion collisions, polarized scattering, and collider phenomenology are reported.     

High Precision Characterisation of Semiconductor Bolometers

We describe techniques for testing and characterising semiconductor bolometers, using the bolometer model presented in Sudiwala et. al. [1]. The procedures are illustrated with results from a prototype bolometer for the high frequency instrument (HFI) in the Planck Surveyor cosmic microwave background mission. This is a bolometer using spider-web geometry and a neutron transmutation doped (NTD) germanium thermistor, designed for operation at 100 mK. Details are given of the laboratory facility used to take data at temperatures from 70 mK to 350 mK. This employs an adiabatic demagnetisation refrigerator to cool the detector and optics. The spatial and spectral properties of the optical system are controlled using feedhorns and edge filters. To characterise the bolometer, blanked and optically loaded load curves were measured over a range of temperatures, and the response to modulated radiation was measured as a function of modulation frequency, temperature and bias current. Results for the prototype bolometer show that its behaviour is well represented by an ideal thermal detector down to a temperature of approximately 100 mK. Below this, non-thermal effects such as electron-phonon decoupling or electric field dependent resistance appear to lead to departure from ideal behaviour. The performance was in good agreement with the design goals for the bolometer.     

All Arbitrarily Fixed Generalized Banana Trees Are Graceful

Consider a set of caterpillars, having equal and fixed diameter, in which one of the penultimate vertices is of arbitrary degree and all the other internal vertices including the other penultimate vertex are of fixed even degree. Merge an end-vertex adjacent to the penultimate vertex of fixed even degree of each of such caterpillars together. The rooted tree thus obtained is called Arbitrarily Fixed Generalized Banana Tree. In this paper we prove that all arbitrarily fixed generalized banana trees are graceful. This would imply that “all banana trees are graceful” and “all generalized banana trees are graceful” as corollaries.