MgCl 2 Support Preparation Techniques and Their Effects on Ziegler-Natta Catalysts Performance in Propylene Polymerization (original) (raw)
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بررسی سیستم پخت دی اکسید منگنز، بر خواص آمیزه های پلیمر پلی سولفاید مایع
2005
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Study of Polymer Composite Cases in Solid Propellant Rocket Motors
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2021
Research subject: Magnesium ethoxide is a metal alkoxide used as a support for preparation of Ziegler-Natta catalyst. This important material which is used in HDPE production plants is not produced in Iran. It forms a complex with the catalyst that results in increase of the number of the reacting transition metal atoms inside it. Therefore the catalyst activity increases. The chemical reaction between magnesium and ethanol, in presence of iodine, results in magnesium ethoxide production. Research approach: In this work, by performing analyses such as thermal gravimetric analysis (TGA), BET and scanning electron microscopy (SEM), the effects of reaction conditions such as iodine/ magnesium, ethanol/magnesium, temperature and mixer speed on morphology and characteristics of magnesium ethoxide were investigated. Main results: By using Iodine, proper morphology of product was obtained. The mixer rotation speed didn›t affect the reaction time. The particle size of the product was depend...
علوم و تکنولوژی پلیمر, 2009
Copolymerization of aniline and 2-anilinoethanol was carried out by electrochemical and chemical polymerization. Homo and copolymer thin films were synthesized electrochemically, under cyclic voltammetric conditions in aqueous solutions of sulfuric acid as electrolyte at room temperature. The films were deposited on the surface of working electrode [Glassy Carbon ()GC)(] versus Ag/AgCl electrode in solution containing 0.1 M mixture of monomers and 1M H2SO4 as electrolyte by applying sequential linear potential scan rate of 25 mV/s between -0.1 to 0.9 V. The cyclic voltammograms CVs)( of obtained copolymer illustrate the formation of copolymer. The homo- and copolymers of aniline ()ANI)( and 2-anilinoethanol 2-ANE)( with different feed ratios of monomers were prepared in 1M H2SO4 in presence of ammonium persulfate [()NH4)(2S2O8] as an oxidant. FTIR spectroscopy and conductivity measurement using four-probe technique were applied for the characterization of the products. The solubilit...
The effect of synthesis method of PbI2 on the hole-transport–free perovskite solar cell performance
Optics and Photonics Society of Iran, 2018
Solar cells fabricated by Organic−inorganic perovskite material because of optimal properties including direct band gap, large absorption coefficients, high carrier mobility and easier process is under consideration by the researcher, recently. One of these promising organic-inorganic material is CH3NH3PbI3 which prepare by mixture of PbI2 and CH3NH3I. In this research, PbI2 powder was synthesized with Golderin technique and by two different calcination procedures and used in preparing perovskite material. Then, the perovskite solar cells with planar structure were fabricated using these materials and also PbI2 powder purchased from Sharif Solar Company as a reference. Then, the solar cell performance including photovoltaic performance and cell efficiencies were compared. Results indicate that the solar cell samples in which PbI2 prepared with heat-shock-process have better photovoltaic performance such as short circuit current density, fill factor and efficiency. It should be noted that these reported data are related to hole-transport-free perovskite solar cells.
2019
s of Papers in English Study of effect of coupling geometry in improvement of thermoelectric properties of polyaniline molecular junction Zahra Golsanamlou1 Meysam Bagheri Tagani1 Hamid Rahimpour Soleimani1* Received: 2016-6-4 Accept: 2018-03-14 Abstract In this paper, we investigate thermoelectric properties of polyaniline molecular junction for three different geometries of the coupling of the molecule to the electrodes including para (symmetric), meta and ortho (asymmetric) configurations. The selected electrodes are threedimensional and face centered cubic (FCC) according to the experimental works. The nonequilibrium Green function formalism is used to obtain thermoelectric coefficients in nonlinear response regime. The Hamiltonian of the system is described by tight-binding method. The results show, in asymmetric coupling, the electrical conductance and thermal conductance decrease whereas thermopower and figure of merit show better behavior and increase in meta and ortho confi...