October 2011

Structural study of complex lipids present in soils: Characterization of monocarboxylic acids resulting from polar lipids fraction alkaline hydrolysis

In acid soils such as turf, the biological activity is reduced, so lipids tend to accumulate. Those lipids are made of two fractions: one fraction, named “simple lipids”, directly analyzable, and the other, named “polar lipids” or “complex lipids”. The structure and origin of these “polar lipids” had been investigated using chemical degradation methods. The degradation...

Author(s): Okome Mintsa Madeleine, Nguele Jean-Calvin, Eba François, Amblès Andréand  Joffre Janie

October 2011

Reverse-flow-injection analysis (FIA) for the determination of Vitamin C in pharmaceutical formulation with chemiluminescence detection

A reverse flow injection chemiluminescence (CL) method for the fast and simple determination of vitamin C has been developed. The CL light observed after luminal-H2O2 aqueous solution was added to the on-line formed Br2 solution from mixing of HBr and KBrO3 solutions was inhibited in the presence of Vitamin C. Based on these facts, a determination method of Vitamin c was developed. In order to...

Author(s): Rebwar O. Hassan and Azad T. Faizullah

October 2011

Potential of nano crystalline hydroxyapatite for lead (II) removal from aqueous solutions: Thermodynamic and adsorption isotherm study

The potential of the synthesized nano hydroxyapatite to remove Pb (II) from aqueous solutions was investigated in batch reactor under different experimental conditions. The study also investigates the effects of process parameters such as initial concentration of Pb (II) ion, temperature and adsorbent mass. Various thermodynamic parameters, such as G°, H° and S° have been calculated. The...

Author(s): I. Mobasherpour, E. Salahi and M. Pazouki

October 2011

Effects of solvent on the UV-visible absorption spectra of acenaphtho(1,2-b) quinoxaline and acenaphtho(1,2-b)benzo(g)quinoxaline

The effects of solvent on the electronic absorption spectra has been used to investigate the structural and molecular properties of acenaphtho(1,2-b)quinoxaline and acenaphtho(1,2-b) benzo(g)quinoxaline. The structures of the compounds have been established by UV-visible spectrophotometer. The spectra behaviours in terms of dipole moments in the ground and excited states have been interpreted and related to the...

Author(s): S. A. Ahmed, N. O. Obi-Egbedi, N. W. Odozi, I. Iweibo and M. D. Adeoye

October 2011

Comparing the conducting properties of benzobispyrrole-derived and benzobisthiazoles-derived squaraines

Smaller or vanishing value of semiconductor energy band-gap (Eg ) is a good factor that determines the conductivity of semiconductor polymers and it has high correlation with the intrinsic electronic, optical and magnetic properties of materials. Squaraine dyes because of their unique optical properties have been shown to be an ideal candidate as one of the building blocks organic dyes with physical property of low HOMO...

Author(s): I. A. ADEJORO and Adebayo A. ADENIYI

October 2011

“Photochemical synthesis and spectroscopic studies of 3, 5-alkyl/aryl substituted-tetrahydro-2H-1,3,5-thiadiazine-2-thione and their complexes with M(CO)4(η2:2- NBD) [M = Cr, Mo and W] as M(CO)4 transfer reagent”

Fifteen new complexes, [M(CO)4(L)2] [M=Cr;  Mo; W]; [L= met-DTTT; et-DTTT; n-pr-DTTT; ph-DTTT and benz-DTTT] have been synthesized by the photochemical exchange reaction of [(η2:2- NBD)M(CO)4] (M= Cr, Mo and W) with 3,5-dimethyl-tetrahydro-2H-1,3,5-thiadiazine-2-thione (met-DTTT),  3,5-diethyl-tetrahydro-2H-1,3,5-thiadiazine-2-thione (eth-DTTT), 3,5-di-n-propyl-tetrahydro-2H-1,3,5-thiadiazine-2-thione...

Author(s): Ayodhya Singh, Munesh Kumar, Manish Kaushik, Anjali Singh and Seema Singh