Abstract: In this work, several metal oxides and zinc salts were used to catalyze propylene carbonate (PC) synthesis from urea and propylene glycol (PG). According to the results of catalytic test and characterization, the catalytic pattern of ZnO was different from that of other metal oxides such as CaO, MgO and La2O3, but similar to that of zinc salts. In fact, the leaching of Zn species took...

The study of the isotopic composition of structural carbonate in fossil vertebrate hydroxylapatite has been hampered by uncertainty concerning sample treatment and arguments about the susceptibility of this material to diagenetic alteration. Our investigation of sample treatment reveals that some methods commonly used to remove organic matter and secondary minerals induce significant isotopic o...

Reconstruction of the human auricle remains a challenge to plastic surgeons, and current approaches are not ideal. Tissue engineering provides a promising alternative. This study aims to evaluate the chondrogenic potential of bone marrow-derived mesenchymal stem cells on a novel, auricular-shaped polymer. The proposed polyhedral oligomeric silsesquioxane-modified poly(hexanolactone/carbonate)ur...

Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction....

Abstract Leaching experiments were performed in calcium aluminate slag with a high-sodium carbonate adaptation of the Pedersen process. A theoretical thermodynamic study pregnant leaching solution was conducted to specify thermodynamically favored species that exist within. Using HSC 9.0 software, carbonation process simulation (neutralization CO 2 gas) simulated. Laboratory verify predictions....

Solvent extraction of copper from the copper leach solution obtained from the ammoniacal carbonate leaching of the Sarcheshmeh copper concentrate was carried out, and the performance of CP-150, LIX984N, and Kelex100 as well as the effects of different parameters involved were investigated. According to the results obtained, the extraction kinetics of all the three extractants was fast. High con...

Industrial processing of mineral ores and concentrates generates large amounts solid residues, which can be landfilled or further processed to recover selected elements depending on its economical profitability. Pressure leaching is a technology enabling high recovery base metals like copper zinc, transferring others lead iron the residue. High temperature pressure such leads formation sparingl...

abstract microbial contaminants transport to groundwater is a serious environmental problem that can result in large outbreaks of waterborne diseases. some of bacteria can travel from vadose zone and cause contamination of groundwater resources. thus, an accurate prediction of transport and fate of pathogenic microorganisms in unsaturated soil is needed to protect groundwater resources. the mai...

Abstract Ferruginous sandstone considered as a one of the economically significant uranium mineralized areas in southwestern part Sinai that located at lower member Um Bogma Formation Abu Thor area. The studied sample was characterized geologically rock contain 450 mg/kg uranium. This work is aimed to compare between eco-friendly bioleaching and conventional leaching processe. efficiency achiev...