Asymptotic N-wave Solutions of the Nonplanar Burgers Equation

In this paper, we construct asymptotic N-wave solutions for the nonplanar Burgers equation as   t →∞  via a balancing argument. These constructed asymptotics are compared with the approximate solutions of the nonplanar Burgers equation obtained by an approach due to Parker ( Acoust. Lett. 4 (1981)). We also present a computationally convenient form for the N-wave solution of the nonplanar Burgers equation modifying Sachdev et al.'s ( Stud. Appl. Math . 103 (1999)) approach. The asymptotic N-wave solutions obtained by balancing argument and modification to Sachdev et al.'s approach are validated by a careful numerical study.     

A Biophysical Study of Ru(II) Polypyridyl Complex,Properties and its Interaction with DNA

Mononuclear Ru(II)Polypyridyl complexes of type [Ru(A)₂BPIIP] (ClO₄)₂.2H₂O, where BPIIP?=?2-(3-(4-bromophenyl)isoxazole-5-yl)-1 H-imidazo [4,5-f] [1, 10] phenanthroline and A?=?bpy?=?bipyridyl (1), phen?=?1,10 Phenanthroline (2), dmb?=?4, 4' -dimethyl 2, 2'- bipyridine (3) & dmp?=?4,4'-dimethyl-1,10 –Ortho Phenanthroline (4), were synthesized and their antibacterial activity were examined. The synthesized complexes were characterized and their interaction with DNA was studied using Computational and Biophysical methods (Absorption, emission methods, and viscosity). Molecular modelling studies were carried out for molecular geometry and electronic properties (Frontier molecular orbital HOMO—LUMO). The electrostatic potential surface contours for the complexes were analysed to give their nucleophilic level of sensitivity. The study reveals that the Ru(II) Polypyridyl complexes bind to DNA preponderantly by intercalation. The results recommend that the phen and dmp complex have more effective binding ability than the bpy and dmb, indicating the role of the ancillary ligand in determining their specificity for DNA binding. Further molecular docking studies suggested an octahedral geometry and bind to DNA by preferential binding to Guanine. The docking study additionally sustains the binding constant data acquired with the absorption and emission techniques.The results reveal that the nature of the ancillary Ligand plays a considerable role for the intercalation of the Ru(II) polypyridyl complex to DNA, which subsequently influences the antibacterial activity. Biological studies conducted on Gram‐Negative (E.coli and K.pneumonia) and Gram-Positive (S. aureus and E. faecalis) bacteria establish that complex 1 and 2 were considerably active against S. aureus and E. coli.

     

Electrical and dielectric properties of rare earth oxides coated LiCoO2 particles

Pure and rare earth oxides (Sm₂O₃, La₂O₃) coated LiCoO₂ nanoparticles were prepared by acrylamide-assisted polymeric citrate and resin-coating processes, respectively. The prepared powders were characterized by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, and impedance spectroscopy. Powder X-ray diffraction patterns confirmed the formation of phase pure LiCoO₂ with nanocrystallite size. X-ray fluorescence spectra confirm the presence of Sm₂O₃ and La₂O₃ in coated samples. The conductivity, dielectric and electric modulus studies of the samples were carried out at room temperature. Dielectric spectra of the samples show the decrease in dielectric constant with an increase in frequency of the applied field. The modulus studies indicate the non-Debye behavior of the samples, which is due to long-time slow polarization and relaxation of hopping charges.     

Generation of 10-Diazolongibornane from Longifolene and Synthesis of Neolongifolene-the Elusive Progenitor of Isolongifolene

Neolongifolene 2, the elusive progenitor of isolongifolene 3, has been synthesised from longifolene in five steps. The strategy consists in generating the crucial longibornyl-10-cation 11 under basic conditions (via 10-diazolongibornane 9 in a protic Bamford-Stevens reaction), which then expels a proton after prior rearrangement, thus affording the target olefin 2; on exposure to any acid, 2 readily collapses into isolongifolene 3.     

1-Butyl-3-methylimidazolium Tetrafluoroborate ([BMIM]BF4): An Efficient Ionic Liquid Medium for the Synthesis of Novel 2-(Oxazolo[5,4-b]pyridin-2-yl)-N-phenylbenzamides

Russian Journal of Organic Chemistry - A series of novel 2-(oxazolo[5,4-b]pyridin-2-yl)-N-phenylbenzamide derivatives have been prepared by one-pot three-component synthesis using...     

Preparation and characterization of nanocrystalline CoFe<Subscript>2</Subscript>O<Subscript>4</Subscript> deposited on SiO<Subscript>2</Subscript>: in situ sol–gel process

In situ base catalyst assisted sol–gel process is used for the synthesis of nanocrystalline CoFe₂O₄ deposition on SiO₂ particles. The SiO₂ particles were prepared using base catalyst assisted sol–gel process and the consecutive formation and deposition of nanocrystalline CoFe₂O₄ on SiO₂ particles was monitored using Powder X ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Thermo Gravimetric And Differential Thermal Analysis (TG/DTA), Scanning Electron Microscopy and Energy Dispersive X ray Spectroscopy (SEM–EDS) and High Resolution Transmission Electron Microscopy (HRTEM). The crystallite size of CoFe₂O₄ is calculated using Scherrer’s formula and it is found to be 8 nm. The HRTEM images and selective area electron diffraction (SAED) results confirmed the formation of nanocrystalline CoFe₂O₄ particles deposited over SiO₂ spheres.     

Allylation of Grignard Reagents: Its Application for the Synthesis of (4E, 7Z)-4,7-Tridecadienyl Acetate,A Sex Pheromone of Potato Tuberworm Moth

Alkylmagnesium halides have been found to react with (Z)-4-benzyloxy-1-chloro-2-butene in presence of HMPA to produce a rearranged product 3-alkyl-4-benzyloxy-1-butene, while in absence of HMPA a normal product (Z)-1-alkyl-4-benzyloxy-2-butene resulted as the predominant product. Latter product has been utilized for the synthesis of (4E, 7Z)-4,7-tridecadienyl acetate, a sex pheromone of potato tuberworm moth.     

Extraction and spectrophotometric determination of vanadium(V) with 8-hydroxyquinoline

The extraction and spectrophotometric determination of vanadium (V) with oxine is investigated at higher acidities than described previously. Under these conditions, n-butanol and other alcohols are found to exert a synergic effect on the extraction of vanadium into benzene. In the presence of alcohol only a 6-fold ligand excess is needed for quantitative extraction in a single operation, the acidity of the aqueous medium being 0.05M with respect to sulphuric or phosphoric acid. The interference of iron(III) in the spectrophotometric determination of vanadium is suppressed by the addition of pyrophosphate. Beer's law is obeyed up to 14.0 mug of vanadium/ml and the sensitivity is 0.008 mug of vanadium/cm(2) at 390 mmu. The composition of the extracted species is found to be vanadium:oxine:n-butanol = 1:2:2.