Effects of sulfonation process on thermal behavior and microstructure of sulfonated polysulfone membranes as a material for Proton Exchange Membrane (PEM)

This paper reports the effect of sulfonation processon thermal behavior and microstrucutre of sulfonated polysulfone membrane. Various degree of sulfonation reactin has been conducted and the sulfonated membranes were characterized by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), x-ray diffraction (XRD) and scanning electron microscopy (SEM). Modifications of the origin polysulfone polymer resulted in an increment value of glass transition temperature (Tg) due to the introduction of sulfonic acid group to the polymer backbone. However, due to some hindrance such as trace amount of organic solvent left during solvent evaporation and high hydrophilicity of the produced sulfonated membranes resulted in decreasing values of Tg. The polymer membrane showed lower degradation temperature as a function of degree of sulfonation. From XRD analysis, it was found that the membrane shows slight crystalline behavior after the sulfonation reaction. Detail discussions and observation of the alteration in microstructure of the sulfonated membrane were supported by SEM micrograph

On Black Attractors in 8D and Heterotic/Type IIA Duality

Motivated by the study of black attractors in 8D supergravity with 16 supersymmetries, we use the field theory approach and 8D supersymmetry with non trivial central charges to shed light on the exact duality between heterotic string on T^2 and type IIA on real connected and compact surfaces {\Sigma}2. We investigate the two constraints that should be obeyed by {\Sigma}2 and give their solutions in terms of intersecting 2-cycles as well their classification using Dynkin diagrams of affine Kac-Moody algebras. It is shown as well that the moduli space of these dual theories is given by SO(1,1)x((SO(2,r+2))/(SO(2)xSO(r+2))) where r stands for the rank of the gauge symmetry G_{r} of the 10D heterotic string on T^2. The remarkable cases r=-2,-1,0 as well as other features are also investigated.Comment: LaTex, 18 pages, 2 figures, To appear in JHE

Extremal Black Attractors in 8D Maximal Supergravity

Motivated by the new higher D-supergravity solutions on intersecting attractors obtained by Ferrara et al. in [Phys.Rev.D79:065031-2009], we focus in this paper on 8D maximal supergravity with moduli space [SL(3,R)/SO(3)]x[SL(2,R)/SO(2)] and study explicitly the attractor mechanism for various configurations of extremal black p- branes (anti-branes) with the typical near horizon geometries AdS_{p+2}xS^{m}xT^{6-p-m} and p=0,1,2,3,4; 2<=m<=6. Interpretations in terms of wrapped M2 and M5 branes of the 11D M-theory on 3-torus are also given. Keywords: 8D supergravity, black p-branes, attractor mechanism, M-theory.Comment: 37 page

Activité hypoglycémique de l’extrait aqueux d’Ajuga iva L. schreber chez les rats diabétiques induite par l’alloxane

Ajuga iva (L) schreber est utilisé en médecine traditionnelle dans le traitement du diabète. Le but de cette étude était d'évaluer l'activité l'hypoglycémique de l'extrait aqueux de la partie aérienne de cette plante sur un modèle animal. L’extrait a été préparé dans de l'eau bouillante et le filtrat aqueux a été lyophilisé et conservé. A iva est une plante capable d’induire une hypoglycémie chez les rats diabétiques. Alloxane a été administré en dose unique (150 mg poids corporel / kg) par injection intra-péritonéal. Des rats femelles Wistar (n = 30) pesant 200 ± 2g divisés en 5 groupes, ont reçu des doses différentes (0,05 g/mL, 0,10 g/mL, 0,15 g/mL) par voie orale. Cette opération est répétée tous les jours pendant 3 semaines. La glycémie a été déterminée par la méthode enzymatique colorimétrique par spectrophotométrie. Seul l’extrait aqueux à forte dose a diminuée le taux du glucose sanguins de 62, 96±7, 30% comparativement au groupe control. Dans la présente étude, le potentiel hypoglycémiant de A iva est démontré chez le rat. Ces résultats confirment l'utilisation de cette plante comme antidiabétique.Mots-clés : Ajuga iva, extrait aqueux, alloxane, activité hypoglycémique, diabète.Hypoglycemic Activity of the aqueous extract of Ajuga iva L. in diabetic rats induced by alloxanAjuga iva (L) schreber is used in traditional medicine in the treatment of diabetes, The purpose of this study was to evaluate hypoglycemic effect of the aqueous extract of aerial parts of this plant on animal model. The extract was prepared in boiling water and the aqueous filtrate was lyophilized and conserved. A iva is a plant capable of inducing hypoglycemia in diabetic rats. Alloxan was administered as a single dose (150 mg body weight / kg) injection intaperitoneal injection. Female Wistar rats (n = 30) weighing 200 ± 2g divided into 5 groups received different doses (0.05 GML-1, 0.10 GML-1, 0.15 g / mL) by oral route. This is repeated every day for three weeks. Blood glucose was determined by the enzymatic and colorimetric method by spectrophotometry. Only the aqueous extract high dose rate decreased blood glucose of 62, 96 ± 7, 30% compared with the control group. In the present study, the hypoglycemic potential of the A iva was demonstrated in rats. These results give support to the traditional use of this plant as antidiabetic herbal medicine.Keywords : Ajuga iva L, aqueous extract, alloxan, diabetes, hypoglycemic activity

Fractional Statistics in terms of the r-Generalized Fibonacci Sequences

We develop the basis of the two dimensional generalized quantum statistical systems by using results on $r$-generalized Fibonacci sequences. According to the spin value $s$ of the 2d-quasiparticles, we distinguish four classes of quantum statistical systems indexed by $s=0,1/2:mod(1)$, $s=1/M:mod(1)$, $s=n/M:mod(1)$ and $0\leq s\leq 1:mod(1)$. For quantum gases of quasiparticles with $s=1/M:mod(1)$, $M\geq 2,$, we show that the statistical weights densities $\rho_M$ are given by the integer hierarchies of Fibonacci sequences. This is a remarkable result which envelopes naturally the Fermi and Bose statistics and may be thought of as an alternative way to the Haldane interpolating statistical method.Comment: Late

Étude comparative de l’activité antispasmodique de l’extrait aqueux d’Ajuga iva L. et de l’ibuprofène chez les souris

Ajuga iva (L.) Schreber, utilisé dans la pharmacopée traditionnelle, pour des troubles gastro-intestinaux, le diabète et comme  hypocholestérolémiante. L’étude pharmacologique de l’extrait aqueux d’Ajuga iva (Lamiaceae) a été effectuée à l’aide de modèles animaux. L’évaluation de l’activité analgésique, montre que l’extrait aqueux à 0,4g/ L de cette plante induit une diminution du nombre de crampes abdominales dans le test de writhing provoqué par l’acide acétique à 1% Ajuga iva a un effet analgésique plus efficace que celui de l’ibuprofène, en effet ce dernier provoque une inhibition de la douleur de 77,53±3,80 % et celui de ,l’extrait aqueux d’Ajuga iva de 85,39±4,29 % pour la même concentration (200mg/kg). L’extrait aqueux d’Ajuga iva a des propriétés analgésiques qui justifient son usage traditionnel. Les effets  thérapeutiques sont induits par divers composés révélés lors du tri phyto chimique de cette plante (alcaloïdes, flavonoïdes, polyphénols, saponosides, et tanins catéchiques) qui constituent la base scientifique de l’utilisation thérapeutique traditionnelle de la plante étudiée.Mots- clés : Ajuga iva L., extrait aqueux, effet analgésique, ibuprofène, writhing test