Polar ring galaxies, where matter is in equilibrium in perpendicular orbits around spiral galaxies, are ideal objects to probe the 3D shapes of dark matter halos. The conditions to constrain the halos are that the perpendicular system does not strongly perturb the host galaxy, or that it is possible to derive back its initial shape, knowing the formation scenario of the polar ring. The formatio...

in the present work, impact of lewis acid (la) catalysts bf3, bcl3, and bbr3 on the kinetics andregioselectivity of 1,3-dipolar cycloaddition (1,3-dc) reaction between azidobenzene and acroleinwas theoretically studied using b3lyp/6-31g* level. our results indicate while the uncatalyzed 1,3-dc reaction under investigation takes place via a non-polar, non-regioselective, and lowasynchronous proc...

from rosana's point of view, following the decline of the dominant role of states in the international arena, the world system has changed from a uni-polar to a multi-polar system. in the new system, there are many independent players. in crease in citizen's knowldge and individual expertise is one of the charactristics of our new world. in this era, legitimacy is no longer derived fr...

deproteinisation with acetonitrile (along with methanol or other reagents) is a useful and rapid technique in analysis of drugs or their metabolites in human serum. in this paper application of this simple technique in biopharmaceutical analysis using capillary electrophoresis (ce) is evaluated. some drugs with different ionic and protein binding properties were selected and dissolved in human ...

the waste tyres represent a source of energy and valuable hydrocarbon products. waste tyres were pyrolysed catalytically in a batch reactor under atmospheric pressure. the effects of basic catalysts (mgo and caco3) were studied on the pyrolysis products. the distribution ratio of gas, liquid and char with mgo and caco3 were 24.4:39.8:35.8 wt % and 32.5:32.2:35.2 wt % respectively at 350°c for 2...

pythium irregulare oomycetes adapts with environmental changes including crude oil concentration by changing the composition of lipids in the cytoplasmic membrane and providing the required characteristics for adaptation in improper and stressful environmental situations. it was found that cultivation of pythium irregulare lx oomycetes in the nutrient media with different concentrations of crud...

For polar/nonpolar heterostructures, Maxwell's theory dictates that the electric potential in the polar components will increase divergently with the film thickness. For LaAlO₃/SrTiO₃, a conceptually intriguing route, termed charge reconstruction, has been proposed to avert such "polar catastrophe". The existence of a polar potential in LaAlO₃ is a prerequisite for the validity of the charge re...

We discuss some recent results of us regarding a class of polar spaces which includes the nonembeddable polar spaces introduced by Tits [3]. These results include an elementary construction of the polar space, a construction of a polarized embedding of the corresponding dual polar space and the determination whether this projective embedding is universal and unique (as a polarized embedding).

Some new perturbation bounds of the positive (semi) definite polar factor and the (sub) unitary polar factor for the (generalized) polar decomposition under the general unitarily invariant norm and the spectral norm are presented. By applying our new bounds to the weighted cases, the known perturbation bounds for the weighted polar decomposition are improved. 2014 Elsevier Inc. All rights reser...

plants produce a diverse array of secondary metabolites, many of which have antimicrobial activity. otostegia persica bioss. (labiatae) grows in south east of iran. no previous investigation on antimicrobial effects of this plant has been reported. thus, the aim of this work was to examine the antimicrobial effect of o. persica extracts with different polarity on several microorganisms. aerial ...