Fluctuation study of pionisation in ultrarelativistic nucleus-nucleus interaction

The scaled factorial moments and the multifractal moments have been investigated in differentη-intervals to study the dynamical fluctuation of pions produced in 200 AGeV³²S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process.     

Vanadium(III) complexes of salicylaldehyde thiosemicarbazones

Hexacoordinate complexes of vanadium(III) containing tridentate ONS chelating substituted salicylaldehyde thiosemicarbazones have been prepared and characterised by elemental analysis, i.r. and u.v.–vis. spectroscopy and cyclic voltammetry.     

Fluctuation study of pionisation in ultrarelativistic nucleus-nucleus interaction

The scaled factorial moments and the multifractal moments have been investigated in different??-intervals to study the dynamical fluctuation of pions produced in 200 AGeV³²S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process.     

Dissipative Waves in a Relaxing Gas Exhibiting Mixed Nonlinearity

We consider a weakly dissipative quasilinear system of PDEs, governingthe unsteady one-dimensional motion of a relaxing gas, and investigatethe effects ofhigher order terms and the source term, present in the differentialsystem, on the wave motion associated with it. The undisturbed stateof the medium, which is assumed to be uniform and at restadmits mixed nonlinearity, i.e., the quadratic nonlinearity parameter inherent in the system changes sign depending on the basestate. The method of multiple scales is employed to determine theevolution equation governing small perturbations to the state where is of O(), and the effects of nonlinearity arenoticeable over times of order O(^–2).     

Antibacterial behaviour of quaternized poly(vinyl chloride)-g-poly(4-vinyl pyridine) graft copolymers

Amphiphilic graft copolymers consisting of poly(vinyl chloride)(PVC) main chains and poly(4-vinyl pyridine)(P4VP) side chains were synthesized via atom transfer radical polymerization(ATRP) using direct initiation of chlorine atoms. The successful synthesis of PVC-g-P4 VP graft copolymers was confirmed by Fourier transform infrared spectroscopy(FTIR) and proton nuclear magnetic resonance(1H-NMR). Transmission electron microscope(TEM) and small angle X-ray scattering(SAXS) analysis showed that PVC-g-P4 VP exhibited microphase-separated, ordered structure with 37.6 nm of domain spacing, which was not observed in neat PVC. For antibacterial applications, the tertiary nitrogen atoms of PVC-gP4 VP was quaternized using 1-bromohexane, as confirmed by FTIR measurements. Bacteria including Escherichia coli(E. coli), Staphylococcus aureus(S. aureus), Bacillus cereus(B. cereus), and Pseudomonas aeruginosa(P. aeruginosa) were completely killed in 24 h on the quaternized PVC-g-P4VP(46% grafting) surface, indicating its excellent antibacterial behavior while it showed to be cytotoxic to mammalian cell.     

Optical Generation of mm-Wave Signal Through Optoelectronic Phase-Locked Loop

In this paper, we propose a scheme for the generation of low phase noise tunable mm-wave signal by beating two lightwaves in a photodiode. These two lightwaves are made phase coherent by an optoelectronic phase locked loop.Calculated mm-wave power at a frequency of 60 GHz is found to be -4 dBm.     

Total ionization cross section in electron-hydrogen scattering

The total ionization cross section in electron-hydrogen scattering in the energy range 20.4–68.0 eV has been calculated by a method in which the initial state of the system is treated by a distorted wave polarized orbital method and the final state is described by (1) a product of two unscreened Coulomb functions and (2) a product of a plane wave and a Coulomb function. The corresponding two sets of results using a plane wave in the incident channel have also been reported. The present results where both the electrons are represented by Coulomb waves are in closer agreement than other theoretical predictions With measured values.     

Divergent cycloaddition and ring-closing metathesis approaches to indolizidine and pyrrolo[1,2-a]azepine skeletons from a chiral precursor: an expeditious route to (-)-8-epi-swainsonine triacetate

[reaction: see text] A divergent strategy for the synthesis of diverse azabicyclic ring systems has been developed in which a chiral N-allylpyrrolidine derivative, obtained from a carbohydrate precursor was converted to (-)-8-epi-swainsonine triacetate by RCM and to a pyrrolo[1,2-a]azepine derivative and a 3-hydroxymethyl-substituted indolizidine by N-allylcarbohydrate nitrone and nitrile oxide cycloadditions.     

In vitro nonenzymatic glycation of DNA nucleobases: an evaluation of advanced glycation end products under alkaline pH

The advanced glycation end products (AGEs) of DNA nucleobases have received little attention, perhaps due to the fact that adenine, guanine, cytosine and thymine do not dissolve under mild pH conditions. To maintain nucleobases in solution, alkaline pH conditions are typically required. The objectives of this investigation were twofold: to study the susceptibility of DNA nucleobases to nonenzymatic attack by different sugars, and to evaluate the factors that influence the formation of nucleobase AGEs at pH 12, i.e., in an alkaline environment that promotes the aldo–keto isomerization and epimerization of sugars. Varying concentrations of adenine, guanine, thymine and cytosine were incubated over time with constant concentrations of D-glucose, D-galactose or D/L-glyceraldehyde under different conditions of temperature and ionic strength. Incubation of the nucleobases with the sugars resulted in a heterogeneous assembly of AGEs whose formation was monitored by UV/fluorescence spectroscopy. Capillary electrophoresis and HPLC were used to resolve the AGEs of the DNA adducts and provided a powerful tool for following the extent of glycation in each of the DNA nucleobases. Mass spectrometry studies of DNA adducts of guanine established that glycation at pH 12 proceeded through an Amadori intermediate.