Search for: inorganics
Total 106 records
Desulfurization of Tabas coal with microwave irradiation/peroxyacetic acid washing at 25, 55 and 85 °C, Article Fuel ; Volume 83, Issue 7-8 , 2004 , Pages 943-949 ; 00162361 (ISSN) ; Rezai, B ; Vossoughi, M ; Osanloo, M ; Sharif University of Technology
Tabas coal sample from Iran was desulfurized with combination of microwave irradiation and peroxyacetic acid washing in a batch reactor. The effect of irradiation time and power, peroxyacetic acid reaction time and temperature and particle size on reduction of sulfur was investigated. For microwaved/acid washed samples, depending on desulfurization conditions, the reduction in pyritic, organic and total sulfur ranged from 26 to 91, 2.6 to 38.4 and 17 to 65%, respectively. Microwave irradiation had positive effect on desulfurization with peroxyacetic acid. For <300 μm size fraction, after irradiation, the reduction enhanced from 49.9 to 86.6% in pyritic sulfur, 23.8 to 35% in organic sulfur...
Synthesis and Application of Aminophenolic Ligands in Preparation of Perovskite-type Inorganic Membranes, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram
Inorganic membranes are a group of compounds which are used in gas separations such as isolating of oxygen from air and/or in petrochemical process like OCM, POM. These days, a variety of research is being conducted to synthesize these membranes from perovskite structures with formulation of ABO3. These compounds have various production procedures and various final perovskite compounds. The purpose of this project is to synthesis and identification of a group of phenolic amino acidic derivatives as new chelating agents, and their use in synthesis of perovskite membranes. For this, novel phenol derivatives of glycine, alanine, β- alanine and leucine amino acids were synthesized and...
Article Journal of the Iranian Chemical Society ; Volume 17, Issue 6 , 31 January , 2020 , Pages 1259-1281 ; Keikavousi Behbahan, A ; Sharif University of Technology
Heavy metals belong to a group of lethal environmental pollutants. Ongoing efforts targeted at safeguarding public health have led to considerable attention being focused on methods that allow efficient extraction of these toxic substances. Polymer nanocomposites (PNCs) with their special characteristics are a class of adsorbents that demonstrate high potential for use in heavy metal extraction. As this process of removal is predominantly governed by adsorption, various parameters in PNCs’ chemical structure, as well as the metal solutions, can have a significant effect on the adsorption process. Herein, this review undertakes a survey of recently developed PNCs and their metal adsorption...
M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahab ; Taghikhani, Vahid
Quartz crystal microbalance (QCM) is a piezoelectric sensor used to measure the mass of adsorbent deposition at the nanoscale on the surface, real-time and non-destructively. The QCM technique has recently gained extensive attention in the chemical and oil industries and other research fields such as medicine and nanotechnology due to its various applications in the advanced sciences. This technique provides comprehensive insights to scientists in the field of phase equilibrium of low-solubility and solid-liquid interactions. Therefore, many attempts have been made to investigate the interaction phenomenon mechanistically using QCM.Scale formation can have many adverse effects, and...
Synthesis, Characterization and Application of Inorganic Nanosystems based on Biocompatible and Highly Tunable Materials for Targeted Delivery and Release of Gene and Drug, Ph.D. Dissertation Sharif University of Technology ; Bagherzadeh, Mojtaba
In this dissertation, an attempt has been made to prepare a library from most of the inorganic and organic compounds in order to strengthen the use of nanosystems for the purpose of controlled delivery and release of drugs and genetic material. In this regard, a complete set of compounds based on metal nanoparticles, layered double hydroxides, metal-organic frameworks, graphene oxide and carbon nanotubes were designed, synthesized and characterized, and nanocomposites and hybrids of them based on palladium, zinc, copper and nickel were designed as well. The nano-stable system is designed with positive surface potential, very low cytotoxicity, biodegradability and acceptable environment as...
Role of different compatibilizing approaches on the microstructure and mechanical properties of polypropylene/talc composites, Article AIP Conference Proceedings ; Vol. 1593, issue , 15- 19 July , 2014 , pp. 428-431 ; ISSN: 0094243X ; Bagheri, R ; Sharif University of Technology
Since in a highly filled polymer, a major problem arises from non-uniformity of properties due to the poor dispersion of filler, the application of coupling agents have been directed to overcome this problem and also to enhance the mechanical performance of the composites by improving the adhesion at the interface. In this study, a comparison between two major coupling approaches is conducted: 1) Using PPgMA as a kind of compatibilizer which changes the nature of the matrix, 2) Using titanate coupling agent which takes action at the interface and reacts with hydroxyl groups at the inorganic filler surface, resulting in the formation of monomolecular layer on the inorganic surface to increase...
Article International Journal of Engineering, Transactions A: Basics ; Vol. 27, issue. 7 , 2014 , p. 1133-1138 ; Kasaeian, A. B ; Nikfarjam, A. R ; Mohammadpour, R ; Sharif University of Technology
In this work, a comparative study of hybrid solar cells based on P3HT and TiO2 nanofibers was accomplished. Electrospinning, a low cost production method for large area nanofibrous films, was employed to fabricate the organic-inorganic hybrid solar cells based on poly (3-hexylthiophene) and TiO2 nanofibers. The performance of the hybrid solar cells was analyzed for four density levels of TiO2 nanofibers which resulted in the average power conversion efficiency of about 0.0134% under AM 1.5 simulated illuminations (100 mWcm-2). It is found that the higher densities of TiO2 lead to more interface area and generating exciton, so the power conversion efficiency will be increased till the active...
Nanocrystalline copper doped zinc oxide produced from copper doped zinc hydroxide nitrate as a layered precursor, Article Advanced Powder Technology ; Volume 23, Issue 3 , 2012 , Pages 279-283 ; 09218831 (ISSN) ; Bagheri, N ; Sadrnezhaad, S. K ; Sharif University of Technology
Undoped and copper doped nanostructured zinc oxides were synthesized by using a series of synthetic layered material, undoped and copper doped zinc hydroxide nitrates at various molar percentages of copper (2-10) within the layers as precursors. The layered materials were heat-treated at 500 °C to produce zinc oxide nanostructures with crystallite sizes in the range of 23-35 nm. Optical studies of the nanostructured copper doped zinc oxides showed the decrease in band gap with increasing content of the doping agent, copper
Effect of bromine doping on the charge transfer, ion migration and stability of the single crystalline MAPb(Br: XI1- x)3photodetector, Article Journal of Materials Chemistry C ; Volume 9, Issue 42 , 2021 , Pages 15189-15200 ; 20507534 (ISSN) ; Prochowicz, D ; Kruszyńska, J ; Satapathi, S ; Akin, S ; Kumari, H ; Kumar, P ; Fazel, Z ; Tavakoli, M. M ; Yadav, P ; Sharif University of Technology
Royal Society of Chemistry 2021
Organic-inorganic halide perovskites (OIHPs) have emerged as a promising semiconductor for the fabrication of efficient optoelectronic devices such as photodetectors (PDs). Among all the perovskite compositions, the mixed-halide MAPb(BrxI1-x)3 formulations have gained more attention for photodetection application thanks to their tunable optoelectronic properties and great stability. However, there is still a lack of sufficient understanding of the effect of Br doping on the stability and physical properties of MAPb(BrxI1-x)3 based PDs. In this work, we prepare a series of MAPb(BrxI1-x)3 (x = 0, 0.04, 0.08, 0.12, and 0.16) single crystals (SCs) and investigate the influence of the Br content...
M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram
The purpose of this project is the synthesis and characterization of a group of phenolic amino acidic derivatives that are studied in both solid phases as well as their solutions. For this, new phenol derivatives of serin and isoleucine amino acids were synthesized and characterized by 1H NMR , 13C NMR, IR spectroscopy as well as elemental analysis. These ligands were utilized to prepare LSF perovskite membrane. According to their XRD patterns, it was concluded that the powdered precursor prepared by serin derivative has shown better qualification and less intermediate phase in the synthesized perovskite membrane similar to the sample prepared by applying EDTA. Furthermore, in the previous...
Article Solar Energy ; Volume 223 , 2021 , Pages 106-112 ; 0038092X (ISSN) ; Heidariramsheh, M ; Javadpour, S ; Ghavaminia, E ; Mahdavi, S. M ; Taghavinia, N ; Sharif University of Technology
Elsevier Ltd 2021
One of the key parts of perovskite solar cells which has great influence on their performance and stability is hole transporting layer. Spiro-OMeTAD is extensively used as organic hole transporting material in perovskite solar cells. However, Spiro-OMeTAD is expensive and has low chemical stability. In this study, the solution processed Sb2S3 and Cu3SbS4 nanocrystals have been synthesized and then the n-i-p mesoscopic perovskite solar cells have been fabricated using Spiro-OMeTAD, Sb2S3 and Cu3SbS4 nanocrystals as hole transporting layer at ambient air condition. It is shown that the conduction and valence band levels of the synthesized Sb2S3 and Cu3SbS4 nanocrystals are in the proper...
M.Sc. Thesis Sharif University of Technology ; Taghavinia, Nima
UF membranes are widely used in various industries now, a major type of these membranes are ceramic membranes which are resistant to high temperatures and corrosive fluids. In this thesis we developed an anisotropic UF ceramic membrane based on 20nm TiO2 nanoparticles on a prous sustrate. We had two major challenges, the first one was to find a suitable prous substrate and the second one was to find an appropriate coating method. Our main task was to optimise the process conditions to achive a crackless and uniform membrane layer with minimal ups and downs. Lots of coating methods and TiO2 inks have been tried, finally we used a coating method which we called it “Soft Blade Coating”, with...
M.Sc. Thesis Sharif University of Technology ; Taghavinia, Nima
In this research, we fabricated and characterized hybrid organic-inorganic perovskite solar. The purpose of this study was the fabrication of multi-cationic perovskite films with vapor-assisted solution process, which was carried out in two different atmospheric and low-pressure conditions. In this regard, the reference cells with CH3NH3PbI3 and HC(NH2)2PbI3 compositions were made, which yielded 15.2% and 7.19% efficiencies in atmospheric conditions, and 6.38% and 2.65% in low pressure conditions, respectively. To increase the stability and to improve cell device performance, Br anion was added to the CH3NH3PbI3 structure. In optimum conditions, the conversion efficiency was 12.18%. Further...
M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram
In our previous work, we have been undertake complexion of new amino phenolic ligand with Fe(III) and Co(II) in order to synthesis LSCF - and LSF - type perovskite inorganic membranes. In this study, the interactions between Co(II) and Fe(III) cations and the mentioned ligands were investigated their by cyclic voltammetry technique. In aqueous solution, it was found that chelate ring size has more prominent effect on the ligand-metal interaction than the related amino acid substitution. Accordingly, the amino phenol substituted...
Synthesis and Study of the Interaction of Aza-Crwon Macrocyclic Ligands with Carboxylate Side Arms with Cd Salts, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram
In the present study, the coordination chemistry of an amino acid azacrown macrocycle ligand bearing one carboxylic acid arm (MA1) was investigated by employing NMR spectroscopy, crystallography and computational chemistry. MA1 was synthetized by the reaction of chloroacetic acid with the parent azacrown macrocycle and its purity was confirmed with 13C and 1H NMR for the first time. A new MA1 homologue, MA3 was also successfully prepared and characterized with NMR, mass spectrometry, and elemental analysis. NMR studies showed that MA1 binds to cadmium via the carboxylate arm in solution. Crystallographic studies showed that MA1 formed a one-dimensional polymer with cadmium, wherein the...
Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Vol. 228, Issue. 13 , December , 2014 , pp. 2475-2486 ; ISSN: 09544100 ; Soltani, M. R ; Sharif University of Technology
The hybrid rocket motor is a kind of chemical propulsion system that has been recently given serious attention by various industries and research centers. The relative simplicity, safety and low cost of this motor, in comparison with other chemical propulsion motors, are the most important reasons for such interest. Moreover, throttle-ability and thrust variability on demand are additional advantages of this type of motor. In this paper, the result of an internal ballistic simulation of hybrid rocket motor in a zero-dimensional form is presented. Further to validate the code, an experimental setup was designed and manufactured. The simulation results are compared with the experimental data...
Synthesis, characterization, and swelling behavior of alginate-g- poly(sodium acrylate)/kaolin superabsorbent hydrogel composites, Article Journal of Applied Polymer Science ; Volume 105, Issue 5 , 2007 , Pages 2631-2639 ; 00218995 (ISSN) ; Ghasemzadeh, H ; Soleyman, R ; Sharif University of Technology
A novel superabsorbent composite based on sodium alginate and the inorganic clay kaolin was synthesized via the graft copolymerization of acrylic acid (AA) in an aqueous medium with methylene bisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The effects of reaction variables, such as the MBA, AA, and APS concentrations and the alginate/kaolin weight ratio, on the water absorbency of the composite were systematically optimized. Evidence of grafting and kaolin interactions was obtained by a comparison of the Fourier transform infrared spectra of the initial substrates with that of the superabsorbent composite, and the hydrogel structure was confirmed...
Magnetic inorganic-organic hybrid nanomaterial for the catalytic preparation of bis(indolyl)arylmethanes under solvent-free conditions: Preparation and characterization of H5PW10V 2O40/pyridino-Fe3O4 nanoparticles, Article Applied Catalysis A: General ; Volume 468 , 2013 , Pages 75-87 ; 0926860X (ISSN) ; Amini, M. M ; Abdollahi, N ; Aliakbari, A ; Rabiei, S ; Ramshini, H ; Sharif University of Technology
Magnetically separable inorganic-organic hybrid material H 5PW10V2O40/pyridino-Fe 3O4 (HPA/TPI-Fe3O4) nanoparticles provide an efficient and economic route for the synthesis of substituted bis(indolyl)methanes by the electrophilic substitution of indole with various aldehydes and ketones under solvent-free conditions with excellent yields in <30 min. This catalyst was prepared by the chemically anchoring H 5PW10V2O40 onto Fe3O 4 nanoparticles via the use of N-[3-(triethoxysilyl)propyl] isonicotinamide (TPI) linker. High catalytic activity and ease of recovery using an external magnetic field are additional eco-friendly attributes of this new catalytic system. The catalyst was recycled at...
Article Materials Research Bulletin ; Volume 44, Issue 4 , 2009 , Pages 913-917 ; 00255408 (ISSN) ; Kazemian, H ; Kazemeini, M ; Sharif University of Technology
High silicon fly ash (HSFA) utilized as a source of silicon in synthesizing of Na-A, -X and -Y zeolites through alkali fusion followed by hydrothermal treatment at 100 °C for 12 h. Various types of zeolites with different degrees of purity were prepared by changing Si/Al ratio of the reaction mixture from 1.6 to 3.0. In addition, exact boundaries of this ratio for synthesis of each zeolite type were determined. Furthermore, the effect of NaOH amount utilized in alkaline fusion step on crystalinity of samples investigated. The synthesized zeolites were characterized using various techniques including; XRD, TGA, FTIR, SEM and BET. The ion-exchange behaviors of zeolitic samples tested with...
Hole transport material based on modified N-annulated perylene for efficient and stable perovskite solar cells, Article Solar Energy ; Volume 194 , 2019 , Pages 279-285 ; 0038092X (ISSN) ; Amini, M ; Heydari, M ; Ahangar, H ; Keshavarzi, R ; Zhang, J ; Mirkhani, V ; Sharif University of Technology
Elsevier Ltd 2019
N-annulated perylene based materials show outstanding and tunable optical and physical properties, making them suitable to be charge transport materials for optoelectronic applications. However, this type of materials has so far not been well studied in solar cells. Here, we develop a new hole transport material (HTM), namely S5, based on perylene building block terms, for organic-inorganic hybrid perovskite solar cells (PSCs). We have systematically studied the influences of the film thickness of S5 on their photovoltaic performance, and a low concentration of S5 with a thinner HTM film is favorable for obtaining higher solar cell efficiency. S5 shows excellent energy alignment with...