Search for: organic-compounds
Total 100 records
Article Materials Chemistry and Physics ; Volume 78, Issue 3 , 2003 , Pages 800-808 ; 02540584 (ISSN) ; Mertens, S. F. L ; Ghorbani, M ; Arshadi, M. R ; Sharif University of Technology
Two newly synthesised Schiff bases [H2A3, N,N′-ortho-phenylene(salicylaldimine-acetylacetone imine) and H2A4, N,N′-ortho-phenylene(salicylaldimine-2-hydroxy-1-naphthaldimine)] were studied as inhibitors for the corrosion of mild steel in 0.5 mol dm-3 sulphuric acid. Results of weight loss, electrochemical impedance and Tafel polarisation measurements consistently identify both compounds as good inhibitors, with efficiencies of around 95% at a concentration of 400 ppm. The inhibition is in both cases of a mixed anodic-cathodic nature. Differences in inhibition efficiency between H2A3 and H2A4 are correlated with their chemical structures. Several adsorption isotherms are assessed, and the...
M.Sc. Thesis Sharif University of Technology ; Kariminia, Hamid-Reza ; Borghei, Mehdi
Odor caused by the release of volatiles from refinery waste, causing environmental pollution and health hazards may occur. Refinery wastewater project in Saeakhs (Khangiran) has been studied. Contaminated water in evaporation ponds at the plant accumulates due to the large volume of incoming water and slow evaporation in summer the water will smell unpleasant. Odor from the ponds due to wind scattered around the refinery and residents will be put at risk. Several tests to identify the source of the odor was designed and implemented. Among these methods, microalgae growth, the import of oil products such as aromatic compounds or mercaptans, and bacterial growth, for each of the hypotheses...
Evaluation Of Nano-sorbents for Removal of Ethyl-benzene from Exhaust of Soil Vapor Extraction (SVE)System, M.Sc. Thesis Sharif University of Technology ; Sayf Kordi, Ali Akbar ; Alaiee, Ebrahim ; Tasharrofi, Saiedeh
Volatile organic compounds are major cause of air pollution. In this work, Nano porous material named MIL-101(Fe), MIL-53(Fe), MIL-101(Fe) and MIL-88(Fe) as an adsorbent for the removal of ethyl benzene have been synthesized hydrothermally. The materials were characterized by Fourier-transform infrared (FT-IR) spectroscopy, Surface Analysis Systems (ASAP), and x-ray diffraction (XRD) analysis. Adsorption isotherms of ethyl benzene on the materials were measured experimentally in case of 0-1000ppm concentration of ethyl benzene in air and pressure 1 atmosphere. The mixture of air and VOC (ethyl benzene) with concentration of 100, 250, 500 and 1000 ppm and flow rate of 400, 1030, 1525 and 2025...
Article Scientia Iranica ; Volume 19, Issue 3 , June , 2012 , Pages 551-554 ; 10263098 (ISSN) ; Saidi, M. R ; Sharif University of Technology
Dithiocarbamic acids and thiols are employed in the Bargellini reaction to generate useful intermediates for the synthesis of organic molecules. This is the first time that dithiocarbamic acids are used as nucleophile in this reaction
Reduced graphene oxide–melamine formaldehyde as a highly efficient platform for needle trap microextraction of volatile organic compounds, Article Microchemical Journal ; Volume 157 , 2020 ; Allahdadlalouni, M ; Baktash, M. Y ; Bagheri, H ; Sharif University of Technology
Elsevier Inc 2020
A superhydrophobic extractive phase was prepared and packed in a needle trap microextraction device for extraction of volatile organic compounds, followed by their determination by gas chromatography. The superhydrophobic phase was prepared by surface modification of melamine formaldehyde (MF) sponge embedded by reduced graphene oxide (rGO). The overall properties of the modified MF along with its high sorption capacity and low cost fabrication were indicative of its feasibility to be highly suitable for extraction of organic pollutants. The determined water contact angle (>150o) from the surface of melamine formaldehyde–reduced graphene oxide (MF–rGO) revealed its high affinity toward...
Article ASME International Mechanical Engineering Congress and Exposition, IMECE 2007, Seattle, WA, 11 November 2007 through 15 November 2007 ; Volume 11 PART A , 2008 , Pages 99-104 ; 079184305X (ISBN); 9780791843055 (ISBN) ; Ahmadian, M. T ; Vafai, A ; Sharif University of Technology
Molecular structural mechanics is implemented to model vibrational behavior of defect free single-layered graphene sheets (SLGSs) at constant temperature. To mimic these two-dimensional layers, zigzag and armchair models with cantilever and bridge boundary conditions are adopted. Fundamental frequencies of these nano structures are calculated, and it is perceived that they are independent of the chirality and aspect ratio. Effects of point mass and atomistic dust on the fundamental frequencies are also considered in order to investigate the possibility of using SLGSs as sensors. Results of exhibit the principle frequencies are highly sensitive to the added mass in the order of 10-6fg....
Article Journal of Chemical Technology and Biotechnology ; Volume 78, Issue 7 , 2003 , Pages 795-801 ; 02682575 (ISSN) ; Dehghanzadeh, R ; Hakimjavadi, M ; Sharif University of Technology
Two laboratory-scale biofilters filled with the same type of packing material were operated at different gas flow rates and influent concentrations of toluene and xylene in order to investigate their performance in treating waste gas streams. The columns contained a mixture of municipal compost as a base material and wood chips as a bulking agent in an 80:20 ratio; the porosity was 54%. Microbial acclimation was achieved by addition of nutrient-enriched solution along with pollutants for a week by daily mixing and natural aeration. During the start-up of the systems with inlet concentrations of 20 and 70 ppm for toluene and xylene, respectively, high biomass growth resulted in pressure drops...
A combined micro-solid phase-single drop microextraction approach for trace enrichment of volatile organic compounds, Article Analytical Methods ; Volume 7, Issue 16 , Jun , 2015 , Pages 6514-6519 ; 17599660 (ISSN) ; Zare, M ; Piri Moghadam, H ; Es haghi, A ; Sharif University of Technology
Royal Society of Chemistry 2015
An attempt was made to combine μ-solid phase extraction and headspace single drop microextraction techniques and use their advantages for trace determination of some volatile organic compounds in aqueous samples. After performing the two-step preconcentration approach, the desired analytes were determined by gas chromatography-mass spectrometry. A resorcinol-formaldehyde-based xerogel was used as the extraction medium in the μ-solid phase extraction (μ-SPE) method. Then, the extracted BTEX was eluted with a rather large amount of methanol. To remove the laborious process including solvent evaporation and further reconstitution, which is usually accompanied by loss of analytes and accuracy,...
Optimization and Modification of the Nanostructures Adsorbent for Reduction voc in Flue Gas (Benzene, Toluene, Xylene, Ethyl Benzene), M.Sc. Thesis Sharif University of Technology ; Sayf Kordi, Ali Akbar ; Mahdyarfar, Mohammad ; Tasharrofi, Saiedeh
In this study, In order to reduce volatile organic component (benzene, toluene, xylene and ethyl benzene) some appropriate nanostructures were used. First the appropriate nano structures were identified, then modified and optimized and finally characterized by XRD, SEM, ASAP. Appropriate nano adsorbent such as nano active carbon, single wall and multi wall nano carbon tubs , nano fiber carbon, graphene oxide, aluminum oxide particles, nano-zinc oxide , titanium oxide particles, 13x zeolite and extruded nano carbon tubes, were prepared and optimized, than evaluated from perspective of the crystal structure, surface area and porosity. nano active carbon, single wall and multi wall nano carbon...
Synthesis of Selected Pyridazine-based Organic Compounds and Investigation of Their Inhibitory Effects Against Amyloid Formation, M.Sc. Thesis Sharif University of Technology ; Kalhor, Hamid Reza
At the molecular level, proteins control almost all the biochemical reactions in the cells. In order for proteins to function, they must be able to fold into their unique 3D structure. Deformation of protein structure due to some environmental phenomena such as pH, high temperature, and stress may cause unfolding of proteins and finally result in formation of protein fibrils called "amyloid". Amyloid has been found in a number of human diseases such as Alzheimer, type II diabetes, and Parkinson. Recently pyridazine has been under spotlight due to its unique chemical properties such as high dipole moment and higher solubility in biological solvents. In this study, we aim at using a...
Article Analytica Chimica Acta ; Volume 863, Issue 1 , 2015 , Pages 20-28 ; 00032670 (ISSN) ; Roostaie, A ; Sharif University of Technology
A highly efficient polybutylene terephthalate (PBT)-based nanocomposite containing nickel oxide nanoparticles was synthesized by electrospinning technique and used as a fiber coating for solid phase microextraction. The influential morphological parameters and capability of the prepared nanocomposite including the NiO content, the coating time, the PBT concentration and applied voltage were considered for optimization. The applicability of the synthesized fiber coating was examined by headspace solid phase micro extraction and gas chromatography mass spectrometry detection of some volatile organic compounds in aqueous samples. Among the synthesized nanocomposites and pristine PBT nanofibers,...
Modeling the formation of traditional and non-traditional secondary organic aerosols from in-use, on-road gasoline and diesel vehicles exhaust, Article Journal of Aerosol Science ; Volume 124 , 2018 , Pages 68-82 ; 00218502 (ISSN) ; Hosseini, V ; Sharif University of Technology
Elsevier Ltd 2018
In this study, we implement a numerical model to predict secondary organic aerosol (SOA) formation from semi- and intermediate-volatility organic compounds emitted from in-use gasoline and diesel vehicles. The model is formulated based on the volatility basis set (VBS) approach, and it accounts for OH oxidation of unspeciated low-volatility organics, which are classified by their volatility. This model incorporates SOA formation data from smog chamber and emission measurements of vehicle exhaust in a Hybrid framework to calculate the contribution of both traditional and non-traditional SOA precursors to total SOA formation observed in photo-oxidation experiments. Emission and SOA formation...
Desion an Appropriate Supported transition Metals Oxide Over Alumina Catalyst for Deep Oxidation of Cyclohexane in Air, M.Sc. Thesis Sharif University of Technology ; Khorashe, Farhad ; Kazemini, Mohammad
Volatile Organic Compounds (VOCs) have become an important source of air pollution due to their extended use as solvents in many industrial processes. Aliphatic and aromatic VOC removal from contaminated air can be achieved by a variety of methods including catalytic oxidation, adsorption, and biological treatment. Catalytic oxidation is often the preferred process due to its low cost and high efficiency. Supported transition metal catalysts are effective and inexpensive catalysts for VOC removal from contaminated air. The objective of this project was to prepare low cost transition metal catalysts (Fe, Ni, Co, and Cu) supported on alumina for catalytic oxidation of cyclohexane (as a...
M.Sc. Thesis Sharif University of Technology ; Shaygan Salek, Jalaloddin
Nowadays, increased pollutants in the air threat the society health condition and Volatile Organic Compounds (VOCs) are the most hazardous ones among them. In the present study, catalytic oxidation as a prominent of the VOCs removal method from air, have attracted attentions due to high removal efficiency and suitable kinetic reaction. Because of its common industrial applications, toluene is intended to be eliminated through a low cost carbon supported catalyst which is synthesised in the laboratory. Construction method, carbonaceous support type, catalyst metal and its load, calcination temperature and time are among influencing design characteristics. A combination of Impregnation and...
in Partial Fulfilment of the Requirements for the Degree of Master of Engineering Faculty of Civil Engineering, Department of Water and Environmental Engineering Sharif University of Technology, M.Sc. Thesis Sharif University of Technology ; Arhami, Mohammad ; Abrishamchi, Ahmad
Oil and gas industries are always considered as one of the most polluting industries in the world. Many pollutants are emitted from the industry into the environment every year. Equipment’s leak and flaring off additional gases produced by various processes of oil and gas production are the main sources of waste in these industries. In order to control these hazardous wastes, it is necessary to provide effective solutions and make appropriate decisions so policymakers will be able to implement policies in order to reduce the emissions of air pollutants. In order to reduce the emissions, it is necessary to conduct the correct and reliable methods and have sufficient information about the...
Synthesis and Structural Activity Relationship (SAR) of Novel Pyridazine-based Inhibitors for Inhibition of Amyloid Fibril Formation, and Biosynthesis and Optimization of L-AsparaginaseII Enzyme for Hydrolysis of Non-Native Substrate, M.Sc. Thesis Sharif University of Technology ; Kalhor, Hamid Reza
After proteins, one of the important biological macromolecules, are synthesized by ribosomes,they automatically reach their own special 3-D structure. This native structur or better known as folded state is what determines the function of a protein. In some situations, the proteins become misfolded leading to its lack of biological function through aggregation or fibril formation known as "amyloid". The amyloid fibrils have been shown to be a causative factor in nerve decay such as Alzheimer's. Therefore, inhibition of amyloid formation using different approaches such as synthetic organic and natural compounds has, recently, been under spotlight. A pyridazine basedcompound (RS-0406) has...
M.Sc. Thesis Sharif University of Technology ; Banaei, Ali
In this thesis first of all we investigate phase noise and it's generation factors. Then we design and implement an ultra low phase noise oscillator. To do this, an ultra low phase noise oscillator which is tunable in 1-2GHz with 100MHz steps will be designed. The outline of the circuit is as follows: at the first we design a VCO which is ultra low phase noise and mechanically tunable in 1-2GHz by means of rotation of a handle. Then a phase locked loop will be built with the help of an ultra low phase noise OCXO at 100MHz and one SPD1 which generates harmonics of OCXO's output frequency. For the next, design and implementation of a 1.6GHz oscillator with fixed output frequency has been done....
Organoplatinum(ii) complexes containing chelating or bridging bis(N-heterocyclic carbene) ligands: Formation of a platinum(ii) carbonate complex by aerial CO2 fixation, Article Dalton Transactions ; Volume 40, Issue 37 , Jun , 2011 , Pages 9362-9365 ; 14779226 (ISSN) ; Milić, D ; Kia, R ; Mazloomi, Z ; Abdolahi, H ; Sharif University of Technology
The preparation of two new bis(N-heterocyclic carbene) platinum(ii) complexes, in which NHC rings are joined by a CH2 linker group, is described. While, the chelate complex [PtMe2(bis-NHC1)], 1, was formed with large tert-butyl wingtips, the iso-propyl N-substituent analogue favors formation of the cluster complex [Pt2Me4(μ- SMe2)(μ-bis-NHC2)]2(μ-Ag2Br2), 2, in which two binuclear platinum(ii) complexes are linked together by an Ag2Br2 unit. The chelating platinum complex 1 undergoes aerial CO2 fixation and forms platinum(ii) carbonate complex [Pt(CO3)(bis-NHC1)], 3
Adsorption of terephthalic acid and p-toluic acid from aqueous solution using metal organic frameworks: Effect of molecular properties of the adsorbates and structural characteristics of the adsorbents, Article Desalination and Water Treatment ; Volume 66 , 2017 , Pages 367-382 ; 19443994 (ISSN) ; Khorasheh, F ; Safekordi, A. A ; Sharif University of Technology
Desalination Publications 2017
The adsorptive removal of terephthalic acid (TPA) and p-toluic acid (p-tol) by metal organic frameworks (MOF) of Cu-BTC, Fe-BTC, MIL-101(Cr) and MIL-53(Al) was investigated in this study. The influence of various factors including solution pH, contact time, and initial concentration of TPA and p-tol solutions on the adsorption behavior was evaluated. Different adsorption isotherms and kinetic models were used to fit experimental adsorption data. It was found that the Langmuir and Redlich-Peterson adsorption isotherms were adequate to represent the experimental data (R2 > 0.97) and that the adsorption kinetics was well-represented by a pseudo-second-order kinetic model (R2 > 0.98). The zeta...
Article Petroleum Exploration and Development ; Volume 45, Issue 1 , February , 2018 , Pages 167-171 ; 18763804 (ISSN) ; Ameri Shahrabi, M. J ; Heidari, H ; Valizadeh, M ; Sharif University of Technology
Elsevier B.V 2018
To improve the thermal stability of starch in water-based drilling fluid, monoethanolamine (MEA) was added, and the effect was investigated by laboratory experiment. The experimental results show that the addition of monoethanolamine (MEA) increases the apparent viscosity, plastic viscosity, dynamic shear force, and static shear force of the drilling fluid, and reduces the filtration rate of drilling fluid and thickness of mud cake apparently. By creating hydrogen bonds with starch polymer, the monoethanolamine can prevent hydrolysis of starch at high temperature. Starch, as a natural polymer, is able to improve the rheological properties and reduce filtration of drilling fluid, but it works...