Slip effects in peristalsis

Taking slip condition into account the magnetohydrodynamic peristaltic flow in an asymmetric channel is theoretically analyzed. The analytic solutions for stream function, longitudinal pressure gradient, and temperature have been found in closed form by employing long wavelength and low Reynolds number approximations. A discussion for pressure rise and frictional forces is provided through numerical integration. Finally, the effects of various key parameters are discussed with the help of graphs and tables. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 1003–1015, 2011     

An Efficient Regio and Stereoselective Synthesis of Silyl Enol Ethers

Ketones and aldehydes on treatment with NaBr-Me₃SiCl-Et₃N in DMF at ambient temperature yield silyl enol ethers with high regio- and stereoselecti-vity.     

Sequential coupling/desilylation-coupling/cyclization in a single pot under Pd/C-Cu catalysis: synthesis of 2-(hetero)aryl indoles

A new one-pot synthesis of 2-(hetero)aryl indoles via sequential C-C coupling followed by C-Si bond cleavage and a subsequent tandem C-C/C-N bond forming reaction is described. A variety of functionalized indole derivatives were prepared by conducting this four step reaction under Pd/C-Cu catalysis. The methodology involved coupling of (trimethylsilyl)acetylene with iodoarenes in the presence of 10% Pd/C-CuI-PPh(3) and triethylamine in MeOH, followed by treating the reaction mixture with K(2)CO(3) in aqueous MeOH, and finally coupling with o-iodoanilides. The single crystal X-ray data of a synthesized indole derivative is presented. Application of the methodology, in vitro pharmacological properties of the synthesized compound, along with a docking study is described.     

Synthesis of ethyl zinc fluoroalkoxide complexes and the crystal structure of [EtZn(py){μ-OCH(CF3)2}]2

Fluorinated alkoxide complexes of zinc were synthesized for possible use as precursors to fluorine-doped ZnO films. Diethyl zinc reacted with fluorinated alcohols to form [EtZn(OR_f)]_n (R_f = CH(CF₃)₂, CMe₂CF₃, CMe(CF₃)₂) compounds. The [EtZn(OR_f)]_n compounds reacted with excess pyridine to yield the pyridine adducts [EtZn(py)(μ-OR_f)]₂. The X-ray structure of [EtZn(py){μ-OCH(CF₃)₂}]₂ showed that it has virtual C_i symmetry.     

Effect of pH on the adsorption of Ce3+, Sm3+, Eu3+ and Gd3+ ions on activated charcoal

The adsorption of metal ions such as Ce³⁺, Sm³⁺, Eu³⁺ and Gd³⁺ ions on activated charcoal has been studied as a function of pH. The adsorption mechanism of these ions is discussed in terms of hydrolyzed species formed in aqueous solution at different pH.     

Stretching a Curved Surface in a Viscous Fluid

This work is concerned with the viscous flow due to a curved stretching sheet. The similarity solution of the problem is obtained numerically by a shooting method using the Runge-Kutta algorithm. The physical quantities of interest like the fluid velocity and skin friction coefficient are obtained and discussed under the influence of dimensionless curvature. It is evident from the results that dimensionless curvature causes an increase in boundary layer thickness and a decrease in the skin friction coefficient.     

A Highly Regioselective Iodoenoletherification of α-Allyl-β-ketoesters. A Convenient Route to 2-Alkyl-5-iodomethyl-3-methoxycarbonyl-4, 5-Dihydrofurans

A variety of α-allyl-β-ketoesters (1) containing two different double bonds, undergo highly regioselective iodoenoletherification to give the titled compound (2) in excellent yields.     

An Efficient Synthesis of Silyl Dienol Ethers from α, β-Unsaturated Aldehydes and Ketones

α, β-Unsaturated aldehydes and Ketones when reacted with NaBr-Me₃SiCl-Et₃N in DMF at ambient temperature, yield silyl dienol ethers in high yields.     

Biofabrication of iron oxide nanoparticles by leaf extract of Rhamnus virgata: Characterization and evaluation of cytotoxic,antimicrobial and antioxidant potentials

In the present study, plant‐mediated synthesis of iron oxide nanoparticles (IONPs) using leaves extract of Rhamnus virgata (Roxb.) as a potential stabilizing, reducing and chelating agent is reported. The biogenic IONPs are extensively characterized for their physical and biological properties. The morphology, structure and physicochemical properties of biogenic IONPs were characterized using ultraviolet spectroscopy, X‐ray diffraction, Fourier transform‐infrared analysis, scanning electron microscopy, energy‐dispersive spectroscopy, transmission electron microscopy, Raman spectroscopy and dynamic light scattering. The Scherrer equation deduced a mean crystallite size of ~20 nm for IONPs. Detailed in vitro biological activities revealed significant therapeutic potentials for IONPs. Potential antibacterial and antifungal activities are reported for IONPs. Bioinspired IONPs have shown potential results against HepG2 cells (IC₅₀: 13.47 μg/ml). Dose‐dependent cytotoxicity assays were revealed against Leishmania tropica (KMH₂₃) promastigotes (IC₅₀: 8.08 μg/ml) and amastigotes (IC₅₀: 20.82 μg/ml) using different concentrations of IONPs (1–200 μg/ml). The cytotoxic activity was also studied using brine shrimps, and their IC₅₀ value was calculated as 32.41 μg/ml. Significant antioxidant [TAC (51.4%), DPPH (79.4%) and total reducing power (62%)], protein kinase and alpha amylase inhibition assays were revealed. The biocompatibility assays using red blood cells (> 200 μg/ml) and macrophages (> 200 μg/ml) confirmed the biosafe nature of IONPs. In conclusion, bioinspired IONPs have shown potential biological applications and should be subjected to further research work to develop their nano‐pharmacological relevance in biomedical applications.     

Stability-Indicating High-Performance Thin-Layer Chromatographic Method for the Simultaneous Determination of Quercetin and Resveratrol in the Lipid-Based Nanoformulation

JPC – Journal of Planar Chromatography – Modern TLC - A simple, sensitive, specific, rapid, and accurate high-performance thin-layer chromatographic (HPTLC) method has been developed...