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Synthesis and properties of lead oxide carbonate
, Article Inorganic Materials ; Volume 42, Issue 10 , 2006 , Pages 1099-1103 ; 00201685 (ISSN) ; Alamolhoda, A. A ; Sharif University of Technology
2006
Abstract
PbCO 3·PbO and PbCO 3·2PbO compounds were prepared by thermal methods. The structure of each compound was determined by using XRD technique, and their purity was confirmed by analytical methods (98%). Also the thermal characteristics of each compound were investigated by thermogravimetry. At 600°C both compounds decompose completely and produce lead(II) oxide. © 2006 Nauka/Interperiodica
Amino acids and their complex formation properties with divalent metal ions, a comparative investigation of structure and stability in binary systems
, Article Current Pharmaceutical Analysis ; Volume 10, Issue 2 , 2014 , Pages 122-134 ; ISSN: 15734129 ; Sharif University of Technology
2014
Abstract
A comparative investigation has been developed for the stability constants of several amino acid complexes with divalent metal ions, which have been determined by potentiometric pH titration. Depending on the metal ion-binding properties, vital differences in the building complexes were observed. The present study indicates that in some M(L) complexes, metal ions are arranged in carboxyl groups, but in other M(L)complexes, some metal ions are able to build chelate over amine groups. The results mentioned-above demonstrate that for some M(L) complexes, the stability constants are also largely determined by the affinity of metal ions for amine group. This leads to a kind of selectivity of...
RETRACTED ARTICLE: Study of stabilities of L-cysteine and L-methionine with divalent metal ions: A comparison of thermodynamic data
, Article 5th International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2011 ; 2011 ; 9781424450893 (ISBN) ; Sharif University of Technology
2011
Abstract
The acidity and stability constants of M-Met (M: M2+; Met 1: L-methionine) complexes, determined by potentiometric pH titrations, were used to make a comparative investigation with L-cysteine (Cys). It is shown that regarding to M ion - binding properties vital differences on complex bilding were considered. It is demonstrated, that in M-Met complexes, M ion is coordinated to the carboxyl group, M ion is also able to build macrochelate over amine group. The upmentioned results demonstrate that for M-Met complex the stability constants is also largly determined by the affinity of Cu2+ for amino group but in opposite to Met, some metal ions such as Co2+, Cu2+, and Zn2+ build with Cys 2...
Investigation of heavy metals containing acidic waste waters from coal mine
, Article 2010 4th International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2010, 18 June 2010 through 20 June 2010 ; June , 2010 ; 9781424447138 (ISBN) ; Sharif University of Technology
2010
Abstract
Waste water from ore plant layout central Alborz's coal has been investigated and analyzed. Studies showed that because of acidic character, the waste water contains heavy metals including Cu, Cr, Ba, Zn, V, Sr, Pb, Ni. Considering the importance of this topic for outgoing acidic waste waters which is hazardous for the environment, i.e. heavy metals, the same should not be transferred into the environment. Since their waste water is transferred into nearby agricultural ground, it was developed a method, so that waste water is primarily directed into a slug pond for sedimentation. In the second stage in another pond, the outflow of waste water was treated with chemicals. Also the pH was...
Study of thermal behavior of α-PbO2, using TG and DSC
, Article Journal of Thermal Analysis and Calorimetry ; Volume 92, Issue 3 , 2008 , Pages 917-920 ; 13886150 (ISSN) ; Alamolhoda, A. A ; Hashemian, S. J ; Sharif University of Technology
2008
Abstract
Using two techniques of thermogravimetry and differential scanning calorimetry under O2 gas atmosphere from 25 to 600°C, the thermal behavior of laboratory-produced compound lead(IV) oxide α-PbO2 was investigated. The identity of products at different stages were confirmed by XRD technique. Both techniques produced similar results supporting the same decomposition stages for the compound. Three distinct energy changes were observed, namely, two endothermic and one exothermic in DSC. The amount of ΔH for each peak is also reported. © 2008 Springer Science+Business Media, LLC
Thermal behavior of alkaline lead acetate, a study of thermogravimetry and differential scanning calorimetry
, Article Scientia Iranica ; Volume 15, Issue 4 , 2008 , Pages 435-439 ; 10263098 (ISSN) ; Alamolhoda, A. A ; Hashemian, S. J ; Sharif University of Technology
Sharif University of Technology
2008
Abstract
The compound, alkaline lead acetate, Pb(CH3COO)2·PbO·H2O (ALA), was purchased from the Fluka Company. The X-ray diffraction film and SEM electron microgaph of this compound were obtained and reported in this paper for the first time. The thermal behavior of alkaline lead acetate (ALA) was studied using thermogravimetery (TGA) and Differential Scanning Calorimetery (DSC) techniques under an O2 gas atmosphere from 25 to 600°C. Four distinct energy changes associated with weight changes were observed, all of them being exothermic in the DSC results. The amount of ΔH for each peak is reported. © Sharif University of Technology
An investigation into the structure and thermal properties of lead hydroxide
, Article Scientia Iranica ; Volume 14, Issue 2 , 2007 , Pages 169-173 ; 10263098 (ISSN) ; Alamolhoda, A. A ; Hashemian, S. J ; Sharif University of Technology
Sharif University of Technology
2007
Abstract
The compound, lead hydroxide Pb6O4(OH)4, was prepared by a method used for the first time in the authors laboratory. The compound was identified by XRD and it's purity was determined by analytical methods (100%). The thermal characteristics of this compound were investigated by using a thermogravimetry (TGA). This compound was found to be stable at room temperature and at 160°C will decompose completely to produce lead (II) oxide. © Sharif University of Technology, April 2007
Separation and recovery of cobalt catalyst from wastewater of PTA unit
, Article Reviews in Inorganic Chemistry ; Volume 29, Issue 3 , 2009 , Pages 171-179 ; 01934929 (ISSN) ; Abdolahifar, A ; Jafarbegloo, M ; Sharif University of Technology
2009
Abstract
The goal of this work is separation and recovery of catalyst residue in wastewater and byproducts of PTA (poly terephetalic acid) unit. Catalyst recovery consists in separating the maximum amount of catalyst and changing the same into valuable compounds. The PTA unit uses cobalt catalyst for oxidation reactions. The byproducts, which contain catalyst, were burned. In the case of metal oxide recovery in the ashes of waste materials, we could solve the problem of the Petrochemical Company. This new method may help us to recover catalyst from wastewater in PTA unit, after which small amounts of ions may be absorbed on a column filled with special absorbent, in such a way that the wastewater...
Study of thermal behavior of CrO3 using TG and DSC
, Article Journal of Thermal Analysis and Calorimetry ; Vol. 116, Issue. 2 , 2014 , pp. 915-921 ; ISSN: 13886150 ; Khaleghian, M ; Sharif University of Technology
2014
Abstract
Using two techniques of thermogravimetry and differential scanning calorimetry under O2 and N2 gas atmosphere from 25 to 600 °C, the thermal behavior of chromium(VI) oxide CrO3 was investigated. The identity of products at different decomposition steps was confirmed by XRD technique. Both techniques produced similar results supporting the same steps for the compound. The received products were investigated by SEM electron microscope. The form and the size of crystals were investigated. Three distinct energy changes were observed, namely, two endothermic and one exothermic in DSC. The amount of ΔH for each peak is also reported
Surveying the jagorood river's self-purification
, Article 6th International Conference on Environmental Informatics, ISEIS 2007 ; 21-23 November , 2014 ; Mirzai, M ; Sajadi, S. A. A ; Alamolhoda, A. A ; Sharif University of Technology
2014
Abstract
the development and enlargement of city structure has caused the environmental problems on watershed of Latian dam which is one of the drinking water resourses of Tehran. The enlargement of Lavasan town and existence of an army garrison that it's effluents of treatment plant discharge to this river necessitate a water quality surveillance in entrance area of the dam. The present research includes the survey of this river's self-purification in the mentioned-above area. Numerical analysis is used in different methods to explain self- purification. Frist, we have the numerical analysis and analytical methods for a known sample in order to determine the accuracy and deviation between two...
Studying of possible remedies for solving environment problems of coal spoil and making them economical
, Article 5th International Conference on Environmental Informatics, ISEIS 2006, 1 August 2006 through 3 August 2006 ; 2006 ; Afshoon, M. R ; Hashemian, S. J ; Alamolhoda, A. A ; Sharif University of Technology
International Society for Environmental Information Sciences
2006
Abstract
Site visits of selected factories and mines show large amounts of coal were collected as spoil and waste outside these locations due to un-efficiency of coal exploiting technology from mined material. The coal content of these waste materials is about 60%. In this work, we propose a method to be used for complete consumption of these materials in industry. In some samples, volume and weight of spoils could be decreased by half. This review also shows that aluminum oxide in industrial and minerals spoils are high, in some samples up to 25%. We suggest some remedies, e.g. we can use ashes produced by complete combustion of coal for production of aluminum hydroxide thus making it economical....
Investigation of thermal behavior of α-PbO and β-PbO IN O2 atmosphere
, Article Metalurgija ; Volume 57, Issue 4 , 2018 , Pages 287-290 ; 05435846 (ISSN) ; Nazari Alavi, A ; Mirzai, M ; Sharif University of Technology
Faculty of Metallurgy
2018
Abstract
The compounds α-lead oxide (α-PbO) and β-lead oxide (β-PbO) were purchased from Merck co. and used for thermal investigations in laboratory. The compound was heated in a thermogravimeter at different temperature, from 25 to 400 °C. The used gas atmosphere was O2. The received products were investigated by X-ray diffraction (XRD) technique. The received product Pb3O4 was confirmed by XRD. The textures of two different morphologies of α-PbO, β-PbO and the product Pb3O4 is investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM) techniques. © 2018, Faculty of Metallurgy. All rights reserved
Mechanical design, fabrication, kinematics and dynamics modeling, multiple impedance control of a wrist rehabilitation robot
, Article International Conference on Robotics and Mechatronics, ICROM 2015, 7 October 2015 through 9 October 2015 ; 2015 , Pages 290-295 ; 9781467372343 (ISBN) ; Nasr, A ; Moosavian, S. A. A ; Zohoor, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Rehabilitation is the best approach for patients who suffer physical disability of their upper-limbs. Maintaining the intensity of exercise during treatment is the main factor that makes the robots suitable for rehabilitation since robots do not get tired and do the exercises with constant intensity under supervision of the doctor. Two main categories of rehabilitation robots are End-Effector based robots and wearable robots. According to the fact that most problems occur in need of rehabilitation for hand wrist area, in this paper a wearable rehabilitation robot has been developed for the wrist. Nowadays, wearable robots attract more attention than the other group. Wearable robots are...
Optimization of alginate-whey protein isolate microcapsules for survivability and release behavior of probiotic bacteria
, Article Applied Biochemistry and Biotechnology ; Volume 190, Issue 1 , 2020 , Pages 182-196 ; Alemzadeh, I ; Vaziri, A. S ; Vossoughi, A ; Sharif University of Technology
Springer
2020
Abstract
The present study aimed to improve the survivability of L. acidophilus encapsulated in alginate-whey protein isolate (AL-WPI) biocomposite under simulated gastric juice (SGJ) and simulated intestinal juice (SIJ). Microcapsules were prepared based on emulsification/internal gelation technique. Optimal compositions of AL and WPI and their ratio in the aqueous phase were evaluated based on minimizing mean diameter (MD) of the microcapsules and maximizing encapsulation efficiency (EE), survivability of cells under SGJ (Viability), and release of viable cells under SIJ (Release) using Box-Behnken experimental design. Optimal composition comprising 4.54% (w/v) AL, 10% (w/v) WPI, and 10% (v/v)...
An experimental study on mechanical behavior of a calcite cemented gravelly sand
, Article Geotechnical Testing Journal ; Volume 41, Issue 3 , May , 2018 , Pages 494-507 ; 01496115 (ISSN) ; Haeri, S. M ; Shahrabi, M. M ; Khosravi, A ; Sajadi, A. A ; Sharif University of Technology
ASTM International
2018
Abstract
In the study presented herein, a simple method for laboratory calcite cementation of a reconstituted gravelly sand was presented. This method was used to prepare cemented gravelly sand specimens, which have similar natural characteristics to alluvial deposit of the city of Tehran. The formation and distribution of calcite bonds, as well as the effectiveness of the presented calcite cementation method in increasing interparticle cohesion, as observed in weakly to moderately cemented soil in Tehran, were evaluated by means of chemical analysis, X-ray diffraction technique, and unconfined compressive strength tests. The cementation technique was used to prepare triaxial specimens with calcite...
Stability of binary and ternary copper (II) complexes of 2((4-methyl-5-nitro-6-(pyrrolidine-l-yl)pyrimidine-2-yl) amino) propionic acid in aqueous solution
, Article Scientia Iranica ; Vol. 21, Issue. 6 , 2014 , pp. 2029-2035 ; ISSN: 10263098 ; Bagherzadeh, G ; Khaleghian, M ; Kermani, M ; Sharif University of Technology
2014
Abstract
The acidity and stability constants of M (MNPPAP) (MNPPAP: 2((4-methyl-5-nitro-6-(pyrrolidine-l-yl)pyrimidine-2-yl)amino)propionic acid) M: Cu2+, Cu (Bpy)2+ (Bpy: 2,2'-Bipyridine), or Cu(Phen) (Phen: 1,10-Phenanthroline) complexes were determined by potentiometric pH titration. It is shown that the stability of the binary Cu (MNPPAP) complex is determined by the basicity of the carboxylate group on one side and amine group on the other side. It is demonstrated that the equilibrium, Cu(Har)2+ (H ar: Heteroaromatic ligand such as Bpy or Phen) + Cu(MNPPAP) ^ Cu(Har)(MNPPAP) + Cu2+, is displacement due to the well known experience that mixed ligand complexes formed by a divalent 3d ion, a...
A hybrid deep and machine learning model for short-term traffic volume forecasting of adjacent intersections
, Article IET Intelligent Transport Systems ; Volume 16, Issue 11 , 2022 , Pages 1648-1663 ; 1751956X (ISSN) ; Gholampour, I ; Sajadi, S. R ; Zamani, A. H ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Despite complex fluctuations, missing data, and maintenance costs of detectors, traffic volume forecasting at intersections is still a challenge. Moreover, most existing forecasting methods consider an isolated intersection instead of multiple adjacent ones. By accurately forecasting the volume of short-term traffic, a low-cost method can be provided to solve the problems of congestion, delay, and breakdown of detectors in the road transport system. This paper outlines a novel hybrid method based on deep learning to estimate short-term traffic volume at three adjacent intersections. The gated recurrent unit (GRU) and long short-term memory (LSTM) bilayer network with wavelet transform (WL)...
Encapsulation of food components and bioactive ingredients and targeted release
, Article International Journal of Engineering, Transactions A: Basics ; Volume 33, Issue 1 , 2020 , Pages 1-11 ; Hajiabbas, M ; Pakzad, H ; Sajadi Dehkordi, S ; Vossoughi, A ; Sharif University of Technology
Materials and Energy Research Center
2020
Abstract
The potential utilization of encapsulation techniques in food, pharmaceutical and agricultural products preparation, presents a new alternative for complementary technologies such as targeting delivery vehicles and carriers for active food ingredients. Encapsulation could be accomplished by different techniques like: simple or complex coacervation, emulsification technique, phase separation, spray drying, spray chilling or spray cooling, extrusion coating, freeze drying, fluidized-bed coating, liposomal entrapment, centrifugal suspension separation, co-crystallization and molecular inclusion complexation. Encapsulation is a method by which one bioactive material or mixture of materials is...
Numerical investigation of the swirling air diffuser: Parametric study and optimization
, Article Energy and Buildings ; Volume 43, Issue 6 , June , 2011 , Pages 1329-1333 ; 03787788 (ISSN) ; Saidi, M. H ; Mohebbian, A ; Sharif University of Technology
2011
Abstract
During the recent decade, high induction diffusers have become more appealing in applications which require relatively high ventilation airflow rates, such as clean rooms. In this research, the effect of geometric parameters on the performance of a specific type of swirling air diffuser is investigated numerically. The results show that although the diffuser slots geometry, namely their angle and aspect ratio, is impressive on the diffuser performance, it is not as important as the swirling blade angle and the performance is almost constant in a wide range of slots specifications. The results also demonstrate that the diffuser performance and the resultant indoor airflow distribution highly...
Simulation of two-phase flow by injecting water and surfactant into porous media containing oil and investigation of trapped oil areas
, Article Journal of Petroleum Exploration and Production ; Volume 11, Issue 3 , 2021 , Pages 1353-1362 ; 21900558 (ISSN) ; Jamshidi, S ; Kamalipoor, M ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Nowadays, as the oil reservoirs reaching their half-life, using enhanced oil recovery methods is more necessary and more common. Simulations are the synthetic process of real systems. In this study, simulation of water and surfactant injection into a porous media containing oil (two-phase) was performed using the computational fluid dynamics method on the image of a real micro-model. Also, the selected anionic surfactant is sodium dodecyl sulfate, which is more effective in sand reservoirs. The effect of using surfactant depends on its concentration. This dependence on concentration in using injection compounds is referred to as critical micelle concentration (CMC). In this study, an...