Spectroscopic Study on Interaction of β-Cyclodextrin with Triprolidine Hydrochloride

The complexation of triprolidine hydrochloride （TRP） and β-cyclodextrin （β-CD） in deuterium oxide was investigated by 400 MHz 1^H NMR spectroscopy. The 800 MHz 2D ROESY data revealed that two 1 ：1 and one 2 ： 1 β-CD-TRP inclusion complexes were formed. Both aromatic moieties （p-tolyl and pyridyl ring） has entered into the β-CD cavity, confirming the existence of two different equilibria for 1 ： 1 inclusion complexes in which p-tolyl ring of the guest is more tightly held by the host cavity. The ROE intermolecular interactions provided the plausible structures of these 1 ： 1 and 2 ： 1 stoichiometric inclusion complexes of β-CD-triprolidine hydrochloride in solu- tion.     

Magnetic properties and magnetic structures of CeAl and PrAla (PrAl annealed)

The intermetallic compounds CeAl and PrAl_a (PrAl annealed) crystallize in the Cmcm orthorhombic space group. They exhibit a metamagnetic behavior below their Néel temperatures. Both compounds have the same noncollinear magnetic structure; rare earth atoms are divided into two sublattices with different magnetization axes which make the same angle with the b axis. Inside each sublattice the arrangement of the moments is collinear and antiferromagnetic. We show that the two moment directions are essentially due to the crystal field effects which act on the rare earth ions lying in a low symmetry site.     

Effect of ZnNiCrFe<Subscript>2</Subscript>O<Subscript>4</Subscript> content on structural and dielectric properties of polyaniline based nanocomposites,synthesized via in-situ chemical polymerization

Zn_0.5Ni_0.4Cr_0.1Fe₂O₄ nanopowder and its composite with polyaniline were successfully prepared by using wow sol-gel and in situ chemical polymerization respectively. The samples were characterized by X-ray diffraction and field emission scanning electron microscopy. Dielectric properties were investigated as function of frequency by using impedance analyzer. The results showed the presence of the two intended phases. The ac conductivity was found to obey Jonscher’s universal power law. The dielectric constant and loss showed dispersion in low frequency region. Impedance analysis revealed the semiconducting behavior of the investigated samples.     

Approximations of the nonlinear Volterra's population model by an efficient numerical method

In this paper, we apply the new homotopy perturbation method to solve the Volterra's model for population growth of a species in a closed system. This technique is extended to give solution for nonlinear integro‐differential equation in which the integral term represents the total metabolism accumulated fromtime zero. The approximate analytical procedure only depends on two components. The newhomotopy perturbationmethodwas applied to nonlinear integro‐differential equations directly and by converting the problem into nonlinear ordinary differential equation. We also compare this method with some other numerical results and show that the present approach is less computational and is applicable for solving nonlinear integro‐differential equations and ordinary differential equations as well. Copyright © 2011 John Wiley & Sons, Ltd.     

1H NMR spectroscopic investigation of β-cyclodextrin inclusion compounds with parecoxib

The inclusion complexes of β-CD and parecoxib [PRB] in aqueous solution were investigated using ¹H NMR spectroscopic study revealed the existence of four different equilibria for 1:1 inclusion complexes in which both the aromatic rings of the guest are tightly held by the host cavity. The NMR spectra of the PRB studied in the presence of β-CD are fully assigned and interpreted by means of COSY spectrum for the unambiguous assignment of guest aromatic ring protons. The parallel interpretation of β-CD chemical shift changes and dipolar contacts, with the aid of 2D ROESY, allows the mode of binding to be established for four possible structures of 1:1 PRB-β-CD inclusion complexes.