EPR and optical absorption studies on VO ions in KZnClSO4·3H2O single crystals—an observation of superhyperfine structure

EPR spectra of VO²⁺ ions doped in KZnClSO₄·3H₂O single crystals have been studied at different temperatures. The EPR spectrum shows a well-resolved hyperfine and superhyperfine structure patterns. The angular variation of EPR spectra reveals the presence of more than three magnetic complexes, which correspond to distinct sites of VO²⁺ ion. From the angular variation EPR data, the spin-Hamiltonian parameters are evaluated and discussed. The optical absorption spectrum studied at room temperature shows bands corresponding to C_4v symmetry. From the EPR and optical data, the molecular-orbital bonding coefficient ε² and β² are evaluated and discussed. The observed five-line superhyperfine structure has been attributed to four protons (with I=1/2) from the surrounding water molecules of one of the vanadyl sites.     

Valence band and chemical interactions of Zn/CdSnAs2 interfaces

X-ray photoelectron spectroscopy (XPS) together with argon ion sputtering was used to investigate the interface of the Zn/CdSnAs₂ system at various temperatures. The formation of an intermediate compound between Zn and As is proposed. The surface enrichment of Cd and Sn at 200 and 400°C is explained in terms of bond breaking and lattice strain theories.NCL Communication No. 4352     

Peristaltic motion of a non-Newtonian fluid

Summary To understand theoretically the flow properties of physiological fluids, we have considered as a model the peristaltic motion of a power law fluid in a tube, with a sinusoidal wave of small amplitude travelling down its wall. The solution for the stream function is obtained as a power series in terms of the amplitude of the wave. The stream function and the velocity components are evaluated by solving numerically two point boundary value problems with a singular point at the origin. The influence of the applied pressure gradient along with non-Newtonian parameters on the streamlines and velocity profiles are discussed in detail.     

A short and concise route to total synthesis of Dendrodolide L

A short and efficient method for the stereoselective synthesis of Dendrodolide L has been developed from inexpensive and commercially available starting material. This convergent synthesis utilizes Jacobsen kinetic resolution, regioselective ring-opening of epoxide and Yamaguchi macrolactonization as key steps.     

Stereoselective synthesis of peracetylated (−)-gloeosporiol via acid catalysed intramolecular etherification

A simple and an efficient strategy have been developed for the stereoselective synthesis of peracetylated (?)-gloeosporiol by acid catalysed cyclisation from the commercially available starting materials.     

Third‐order WENO scheme with a new smoothness indicator

In this article, we have devised a new reference smoothness indicator for third‐order weighted essentially non‐oscillatory (WENO) scheme to achieve desired order of convergence at critical points. In the context of the weighted essentially non‐oscillatory scheme, reference smoothness indicator is constructed in such a way that it satisfies the sufficient condition on the weights for the third‐order convergence. The goal is to construct a reference smoothness indicator such that the resulted scheme have to achieve the required order of accuracy even if the first two derivatives vanish but not the third derivative. The construction of such reference smoothness indicator is not possible through a linear combination of local smoothness indicators only. We have proposed a reference smoothness indicator to be of the fourth order of accuracy on three‐point stencil that contains the linear combination of the first derivative information of the local and global stencils. The performance enhancement of the WENO scheme through this reference smoothness indicator is verified through the standard numerical experiments. Numerical results indicate that the new scheme provides better results in comparison with the earlier third‐order WENO schemes like WENO‐JS and WENO‐Z. Copyright © 2017 John Wiley & Sons, Ltd.     

Design,Synthesis, and Anticancer Activity of 1,2,3-Triazole Linked 1,2-Isoxazole-imidazo[4,5-b]pyridine Derivatives

Russian Journal of General Chemistry - A series of novel 1,2-isoxazole-pyridobenzimidazole is synthesized. Structures of the products are supported by 1H and 13C NMR, and mass spectra. All...