We have investigated the electronic structure and thermodynamic properties of supercell of the -Al2O3 by first-principles calculation in framework of density functional theory (DFT) and full potential linearized augmented plane wave (FP-LAPW) with generalized gradient approximation (GGA) and by quasi-harmonic Debye model. Our calculated value for direct band gap of α-Al2O3 is 7.2 eV which i...

expanded graphite nanosheets (eg-nanosheets) were used for adsorption of malachite green (mg) from aqueous solution. the influences of dye concentrations, absorbent dosage, ph values and the temperatures on the adsorption were investigated as well. the dye adsorption experiments were carried out by utilizing batch procedure. eg-nanosheets were initially characterized by scanning electron micros...

application of cogeneration systems based gas turbine for heat and power production is increasing. because of finite natural energy resources and increasing energy demand the cost effective design of energy systems is essential. cgam problem as a cogeneration system is considered here for analyzing. two new approaches are considered, first in thermodynamic model of gas turbine and cogeneration ...

a nanocomposite membrane cu2+ ion-selective electrode has been constructed using a new compound ethyl 1,2,3,4-tetrahydro-4-(4-methoxyphenyl)-6-methyl-2-oxopyrimidine-5-carboxylat (etmoc) as a neutral ionophore. the electrode works properly. it responds to cu2+ ion with a sensitivity of 29.5 ± 0.2 mv/decade over the range 1.0 × 10−9 to 5.0 × 10−1m at ph 3.0-8.0. the limit of detection was 4.5 × ...

abstractin this work, the micro powder was the product of cedar leaf (mpcl) is used as a low-cost adsorbent for the removal of pb2+ ions from aqueous solutions. bath experiments were used to determine the best adsorption conditions the adsorption percentage of pb2+ ions mpcl samples at different initial ph, contact time (tc), adsorbent dosage and temperature (t) were investigated. effective rem...

Surfactant-dye interactions are very important in chemical and dyeing processes. The dyes interact strongly with surfactant and show new spectrophotometric properties, so the UV-vis absorption spectrophotometric method has been used to study this process and extract some thermodynamic parameters. In this work, the association equilibrium between ionic dyes and ionic surfactant were studied by a...

heat recuperation is often used to improve the overall cycle efficiency of gas turbines. however, generally in small- scale gas turbines, it has a negative effect on turbine inlet temperature, pressure ratio and pressure drops, and thus decreases the overall cycle efficiency. in this paper, a thermodynamic model is performed to evaluate recovered heat as a function of heat exchanger effectivene...

in this work, we have studied the solvent effects on values of gibbs free energy, enthalpy. entropy and dipolemoment in spread of solvents around anticancer thug of temreolomide that is an alighting agent. for thispurpose, the quantum mechanic calculations bawd on hanrertnick theory at the sto-36/3-2ith levels havebeen done. moreover, we have compared resulted thermodynamic values in gas phase ...