Valence charge distribution and electric field gradients in GaAsAlAs mixed crystals

Electric field gradients at the arsenic sites in the GaAsAlAs mixed compounds are calculated using the self-consistent pseudo-potential method. The result is in good agreement with recent nuclear quadrupole resonance (NQR) experiments and supports the interpretation that the NQR splittings arise from an Al ion relacing one of the four Ga ions near an As site.     

Series solution of unsteady free convection flow with mass transfer along an accelerated vertical porous plate with suction

The problem of unsteady free convection flow is considered for the series solution (analytic solution). The flow is induced by an infinite vertical porous plate which is accelerated in its own plane. The series solution expressions for velocity field, temperature field and concentration distribution are presented. The influence of important parameters is seen on the velocity, temperature, concentration, skin friction coefficient and temperature gradient with the help of graphs and tables. Convergence is also properly checked for different values of the important parametes for velocity field, temperature and concentration with the help of ħ-curves.     

Inverse Problem for an Integro-Differential Equation of Acoustics

We consider the hyperbolic integro-differential equation of acoustics. The direct problem is to determine the acoustic pressure created by a concentrated excitation source located at the boundary of a spatial domain from the initial boundary-value problem for this equation. For this direct problem, we study the inverse problem, which consists in determining the onedimensional kernel of the integral term from the known solution of the direct problem at the point x = 0 for t > 0. This problem reduces to solving a system of integral equations in unknown functions. The latter is solved by using the principle of contraction mapping in the space of continuous functions. The local unique solvability of the posed problem is proved.     

Organometallic assembling of chitosan‐Iron oxide nanoparticles with their antifungal evaluation against Rhizopus oryzae

The ever‐increasing resistance of plant microbes towards fungicides and bactericides has been causing serious threat to plant production in recent years. For the development of an effective antifungal agent, we introduce a novel hydrothermal protocol for synthesis of chitosan iron oxide nanoparticles (CH‐Fe₂O₃ NPs) using acetate buffer of low pH 5.0 for intermolecular interaction of Fe₂O₃ NPs and CH. The composite structure and elemental elucidation were carried out by using X‐ray power diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X‐ray (EDX), Transmission Electron Microscopy (TEM), Fourier Transformed Infrared Spectroscopy (FTIR) and Ultraviolet Visible Absorption Spectroscopy (UV–vis spectroscopy). Additionally, antifungal activity was evaluated both In vitro and In vivo against Rhizopus oryzae which is causing fruit rot disease of strawberry. We compared different concentrations (0.25%, 0.50%, 075% and 1%) of CH‐Fe₂O₃ NPs and 50% synthetic fungicide (Matalyxal Mancozab) to figure out suitable concentration for application in the field. XRD analysis showed a high crystalline nature of the NPs with average size of 52 nanometer (nm). SEM images revealed spherical shape with size range of 50–70 nm, whereas, TEM also revealed spherical shape, size ranging from 0 nm to 80 nm. EDX and FTIR results revealed presence of CH on surface of Fe₂O₃ NPs. The band gap measurement showed peak 317–318 nm for bare Fe₂O₃ NPs and CH‐Fe₂O₃ NPs respectively. Antifungal activity in both In vitro and In vivo significantly increased with increase in concentration. The overall results revealed high synergetic antifungal potential of organometallic CH‐Fe₂O₃ NPs against Rhizopus oryzae and suggest the use of CH‐Fe₂O₃ NPs against other Phyto‐pathological diseases due to biodegradable nature.     

Nanocrystalline TiO2, via green combustion synthesis,as an efficient and reusable catalyst for the preparation of 1,8‐dioxooctahydroxanthenes and 1,8‐dioxodecahydroacridines

Nanocrystalline TiO₂ is synthesized using a green combustion method and used as a recyclable catalyst for the one‐pot multicomponent synthesis of 1,8‐dioxodecahydroacridines and 1,8‐dioxooctahydroxanthenes, under solvent‐free conditions. This method is mild, environmentally friendly, inexpensive and highly effective for obtaining good to excellent yields of the products. Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis and Characterization of a Cu14 Hydride Cluster Supported by Neutral Donor Ligands

The copper hydride clusters [Cu₁₄H₁₂(phen)₆(PPh₃)₄][X]₂ (X=Cl or OTf; OTf=trifluoromethanesulfonate, phen=1,10‐phenanthroline) are obtained in good yields by the reaction of [(Ph₃P)CuH]₆ with phen, in the presence of a halide or pseudohalide source. The complex [Cu₁₄H₁₂(phen)₆(PPh₃)₄][Cl]₂ reacts with CO₂ in CH₂Cl₂, in the presence of excess Ph₃P, to form the formate complex [(Ph₃P)₂Cu(κ²‐O₂CH)], along with [(phen)(Ph₃P)CuCl].