Islamic Azad University North Tehran Branch

About: Islamic Azad University North Tehran Branch is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Adsorption & Catalysis. The organization has 868 authors who have published 968 publications receiving 9987 citations.

Studying some effective parameters on transesterification reaction to produce biodiesel from safflower oil.

Abstract: Biodiesel fuel, due to uncontrollable prices of fossil fuels, reduction of its resources and environmental pollution, has become increasingly important. Biodiesel (the mono alkyl esters of fatty acids) is a renewable and green energy, derived from vegetable oils and animal fats. The high viscosity of vegetable oils prevents their direct use in diesel engines, so, among different methods of chemical modification, transesterification is used to produce biodiesel. In this study, safflower plant oil was used to produce biodiesel. Safflower oil was extracted by soxhlet apparatus and its physical properties were determined. The effect of molar ratio (oil to alcohol) and amount of catalyst on the conversion of oil to methyl ester was studied. The results indicate that, catalyst amount (1%w/w) and 6:1 molar ratio of alchohol to oil were the optimum conditions for producing of biodiesel and 96% yield of methyl esters has been obtained. Produced biodiesel was within recommended standards of biodiesel fuel (ASTMD675109).

Investigation of the Non-Relativistic Fermi-Gas Model by Considering the Position-Dependent Mass

Abstract: We investigate the Schrodinger equation in the position-dependent mass framework with an infinite square well potential. We apply this approach to a Fermi gas, calculate the density of states of the gas, examine the information entropy, some expectation values and the uncertainty principle.

Determination and preconcentration of manganese using ionic liquid based microextraction technique in biological samples

Abstract: In this work, a procedure for preconcentration and determination of manganese using modified cold-induced aggregation microextraction(CIAME) based ionic liquid with the reagent 1-(2-pyridylazo)-2-naphthol (PAN) as complexing reagent was developed. In the preconcentration step, the mixture was cooled in an ice bath and manganese from 10mL of an aqueous solution was extracted into70µL of ionic liquid, 1-hexyl-3-methylimidazolium hexafluorophosphate [Hmim][PF 6]. After centrifuging the extraction phase was settled. Then, the absorbance of the complex was measured by UV-Vis spectrophotometry. In this study, the effect of matrix ions on the extraction efficiency of Mn +2 were investigated. Also the optimization extraction conditions, such as: pH, PAN concentration, extraction time, addition of salt, ionic liquid volume and centrifugation rate were studied. The relative standard deviation was 1.14 % (n=4). The detection limit of 0.54 ngL -1 and enrichment factor of 70 for Mn +2 were achieved. The presented procedure was successfully applied for determination of manganese in environmental and biological samples.

Molecular characterization of a Squalene epoxidase gene in dermatophyte pathogen Trichophyton tonsurans.

Abstract: Background: Trichophyton tonsurans is one of the dermatophyte fungi which invades the skin and hair of human. Several properties of this fungus have been investigated so far. However a few studies were carried out in the field of molecular biology of this fungus. In the present study, we tried to identify the Squalene epoxidase gene which is related to synthesis of ergosterol in this fungus. Methods: Pairs of 23 and 24 nucleotides primers were designed from highly conserved regions of the similar genes in other fungi. Mentioned primers were utilized in PCR by using isolated genomic DNA of T. tonsurans whereas the PCR fragments were then sequenced. Results and Conclusion: Nucleotides (n = 558) have been sequenced from this new gene which encodes a polypeptide with 186 amino acids. Sequences comparison in gene data banks (NCBI, NIH) for this part of DNA and its deduced amino acid revealed significant homology with members of the eukaryotic Squalene epoxidase. Iran. Biomed. J. 12 (1): 55-58, 2008