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calcium-sulfate
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Rigorous modeling of gypsum solubility in Na-Ca-Mg-Fe-Al-H-Cl-H2O system at elevated temperatures
, Article Neural Computing and Applications ; Volume 25, Issue 3 , September , 2014 , pp 955-965 ; ISSN: 09410643 ; Gharagheizi, F ; Lemraski, A. S ; Jamialahmadi, M ; Mohammadi, A. H ; Ebrahimi, M ; Sharif University of Technology
Abstract
Precipitation and scaling of calcium sulfate have been known as major problems facing process industries and oilfield operations. Most scale prediction models are based on aqueous thermodynamics and solubility behavior of salts in aqueous electrolyte solutions. There is yet a huge interest in developing reliable, simple, and accurate solubility prediction models. In this study, a comprehensive model based on least-squares support vector machine (LS-SVM) is presented, which is mainly devoted to calcium sulfate dihydrate (or gypsum) solubility in aqueous solutions of mixed electrolytes covering wide temperature ranges. In this respect, an aggregate of 880 experimental data were gathered from...
Microscopic Investigation of Formation Damage Inhibitor Effects during Low Salinity Water Injection
, M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahab (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
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...
Fabrication of Bioactive Bone Cement
, M.Sc. Thesis Sharif University of Technology ; Bahrevari, Mohammad Reza (Supervisor) ; Mashayekhan, Shohreh (Supervisor) ; Abd Khodaei, Mohammad Jafar (Supervisor)
Abstract
PMMA bone cement lacks biodegradability and the ability to bond with surrounding bone tissue. Therefore, the development of a new generation of bioactive bone cements that are biodegradable and possess adequate mechanical properties as well as desirable setting time is receiving remarkable interest.In this study, we have developed novel mineral-based bioactive bone cements. Our mineral bioactive bone cements were composed of Calcium Sulfate Hemihydrate, Bioactive Glass, and Tricalcium Silicate. Firstly, a binary system composed of Calcium Sulfate Hemihydrate and Bioactive Glass was optimized based on mechanical and setting behavior. Secondly, Tricalcium Silicate was added to the powder phase...
A newmodel for permeability reduction rate due to calciumsulfate precipitation in sandstone cores
, Article Journal of Porous Media ; Volume 13, Issue 10 , 2010 , Pages 911-922 ; 1091028X (ISSN) ; Soltanieh, M ; Kharrat, R ; Sharif University of Technology
2010
Abstract
In this work, a reliable dimensionless correlation is proposed for prediction of permeability reduction rate in porous media, which is verified by experimental data obtained in this work in glass bead and sand pack as well as the core data from the literature. Although this correlation is based on the data which were obtained in our work in glass bead and sand-packed media at low pressure, it shows considerable flexibility to match with the extracted data for sandstone cores at high pressure, various flow rates, different temperatures and concentrations of calcium, and sulfate ions in brine solutions. In addition, a novel relationship for predicting the rate of precipitation of CaSO4 in...
Characterization of ionic composition of TSP and PM10 during the Middle Eastern Dust (MED) storms in Ahvaz, Iran
, Article Environmental Monitoring and Assessment ; Volume 184, Issue 11 , November , 2012 , Pages 6683-6692 ; 01676369 (ISSN) ; Naddafi, K ; Jaafarzadeh Haghighifard, N ; Mesdaghinia, A ; Yunesian, M ; Nabizadeh, R ; Arhami, M ; Yarahmadi, M ; Sowlat, M. H ; Ghani, M ; Jonidi Jafari, A ; Alimohamadi, M ; Motevalian, S. A ; Soleimani, Z ; Sharif University of Technology
2012
Abstract
Because of the recent frequent observations of major dust storms in southwestern cities in Iran such as Ahvaz, and the importance of the ionic composition of particulate matters regarding their health effects, source apportionment, etc., the present work was conducted aiming at characterizing the ionic composition of total suspended particles (TSP) and particles on the order of ∼10 μm or less (PM10) during dust storms in Ahvaz in April-September 2010. TSP and PM10 samples were collected and their ionic compositions were determined using an ion chromatography. Mean concentrations of TSP and PM10 were 1,481.5 and 1,072.9 μg/m 3, respectively. Particle concentrations during the Middle Eastern...
Analytical modeling of strength in randomly oriented PP and PPTA short fiber reinforced gypsum composites
, Article Computational Materials Science ; Volume 50, Issue 5 , 2011 , Pages 1619-1624 ; 09270256 (ISSN) ; Sangghaleh, A ; Nazari, A ; Pourjavad, N ; Sharif University of Technology
Abstract
Fiber reinforced gypsum are prevalent building materials in which short fibers with high tensile strength are embedded into a gypsum matrix to produce supplemental strong and lightweight construction materials. Due to confrontation to a rising risk of death and economic disaster in earthquake-prone areas, quake-resistant materials and structures should be employed for building constructions. Gypsum based composites as a unique candidate for this purpose reduce the risks and produce much confident construction materials for residential buildings. In this work tensile strength of gypsum composites with different volume fraction of polypropylene (PP) and poly-paraphenylene terephthalamide...