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butyl-acetate
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Preparation of Polyethersulfone Membrane for Separation of Aroma Compounds in Grape Juice
, M.Sc. Thesis Sharif University of Technology ; Roostaazad, Reza (Supervisor) ; Mousavi, Abbas (Co-Advisor)
Abstract
Many aroma compounds of fruit juice recovered by thermal processes like evaporation and distillation can lead to undesirable chemical changes and even their loss. Pervaporation is a promising process for the recovery of volatile organic compounds from their aqueous solutions. In the present work, pervaporation recovery of Butyl acetate as a model solution ofgrape juice aroma compoundwas evaluated with polyethersulfone (PES) and ethylvinylacetate (EVA) membranes. PES membrane generally showed better selectivity so that the separation factor at the concentration of 500 ppmand the temperature of 30°C for PES and EVA membranes, respectively, was 230.78 and 156.9. The effect of two operating...
A novel approach for preparation of CL-20 nanoparticles by microemulsion method
, Article Journal of Molecular Liquids ; Vol. 193, issue , May , 2014 , pp. 83-86 ; Zarandi, M ; Zarei, M. A ; Soleyman, R ; Zeynali, V ; Sharif University of Technology
Abstract
2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) as one of the high energy cage nitramines has been used in various propellants and explosive formulations. The performance of energetic materials depends on its particle size and shape. Therefore, in this research, microemulsion method has been applied for the preparation of CL-20 nanoparticles via oil in water (O/W) microemulsions. The optimized formulation contains water 45%, n-butyl acetate 20.5%, sodium dodecyl sulfate (SDS, as anionic surfactant) 6.5% and 2-propanol (as co-surfactant) 26.5%. CL-20 nanoparticles that were obtained by microemulsion method are spherical with an average diameter of 25 nm, based on TEM image....
Immersed solvent microextraction and gas chromatography-mass spectrometric detection of s-triazine herbicides in aquatic media
, Article Analytica Chimica Acta ; Volume 537, Issue 1-2 , 2005 , Pages 81-87 ; 00032670 (ISSN) ; Khalilian, F ; Sharif University of Technology
Elsevier
2005
Abstract
An immersed solvent microextraction (SME) method was successfully developed for the trace enrichment of s-triazine herbicides from aquatic media. A microdrop of butyl acetate was applied as the extraction solvent. After extraction, the microdrop was introduced directly into a gas chromatography-mass spectrometry (GC-MS) injection port. Some important extraction parameters such as type of solvent, extraction time, stirring rate, and temperature were investigated and optimized. The highest possible microdrop volume of 3 μl, a sampling temperature of 60°C, and use of butyl acetate are major parameters to obtain high enrichment factors. The enrichment factor and linearity was studied by...
Modified solvent microextraction with back extraction combined with liquid chromatography-fluorescence detection for the determination of citalopram in human plasma
, Article Analytica Chimica Acta ; Volume 610, Issue 2 , 2008 , Pages 211-216 ; 00032670 (ISSN) ; Khalilian, F ; Babanezhad, E ; Es haghi, A ; Rouini, M. R ; Sharif University of Technology
2008
Abstract
A modified solvent microextraction with back extraction method (SME/BE) combined with high performance liquid chromatography and fluorescence detection (HPLC-FD) was developed for the determination of citalopram in human plasma. Extraction process was performed in a home-made total glass vial without using a teflon ring, usually employed in SME/BE. Citalopram was first extracted from 0.5 mL of plasma, modified with sodium hydroxide, into hexane. Back extraction step was then performed into 5.2 μL of 45 mM ammonium formate solution (pH 4) using a GC microsyringe. The extract was subsequently transferred into a liner-like vial and then injected into the HPLC system. An enrichment factor of 150...