http://nopr.niscpr.res.in/handle/123456789/43610 Sat, 10 Oct 2026 20:51:04 GMT 2026-10-10T20:51:04Z http://nopr.niscpr.res.in/handle/123456789/43623 Title: Electrochemical studies on the adsorption interaction and corrosion inhibition properties of a substituted triazinone, BCATDT on mild steel in hydrochloric acid Authors: Shainy, K M; Kuruvilla, Mathew; Joseph, Abraham Abstract: A novel triazine based corrosion inhibitor, 6-benzyl-(2-chlorobenzyl) amino 3-thioxo-3, 4-dihydro-1, 2, 4-triazin- (2H)-5-one (BCATDT) has been synthesized and characterized using various spectroscopic techniques. Corrosion inhibition efficiency and other corrosion parameters of BCATDT have been calculated using weight loss measurements, potentiodynamic polarization studies and electrochemical impedance spectroscopy techniques at three different temperatures (303 K, 313 K and 323 K). Among the 0.5 M and 1M HCl solutions 99.55% efficiency is reported for 0.5M solution corresponding to 200 ppm BCATDT. As the acid concentration doubled, only < 7% efficiency decreases even at 323K (92.32%). The potentiodynamic polarization indicates that BCATDT act as an efficient mixed type inhibitor and the most suitable isotherm is found to be the Langmuir adsorption isotherm. The experimental results are then shown to be in conformity with theoretical parameters under B3LYP/6-31G* of Gaussian 03 soft ware. Molecular simulation studies are also performed by Monte Carlo simulation for studying the adsorption of BCATDT on to the various unit cell of iron surface such as Fe (111) Fe (110) and Fe (100) etc. Page(s): 9-20 Mon, 01 Jan 2018 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/43623 2018-01-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/43622 Title: Polyethylene quality control in an industrial scale fluidized bed reactor Authors: Vahidi, Omid; Shahrokhi, Mohammad Abstract: Polymer quality control in an industrial scale polyethylene fluidized bed reactor has been addressed. Since online measurements of polymer properties (melt index and density) are not available, they must be controlled indirectly via other available measurements. In the present paper, two algebraic equations correlating polyethylene melt index and density with the measureable concentrations of chemical components are obtained. Having the desired polyethylene properties and using these correlations, desired concentrations of chemical components are calculated and used via corresponding control loops. By using the infrequently available polyethylene property measurements, the correlation parameters are updated. In order to simulate the fluidized bed reactor behaviour, a comprehensive two phase model including bubble and emulsion phases is used. Six control loops with PI controllers are considered to regulate the reactor operating conditions. To improve the performances of the component concentration loops, ratio control strategy in a cascade framework is implemented. The effectiveness of proposed reactor control structure for several scenarios comprising the rejection of operational disturbances, set-point tracking for polyethylene production amount and grade changes and compensating the model uncertainties is demonstrated via computer simulation. The results indicate that the polyethylene properties are well controlled with the proposed inferential control strategy. Page(s): 21-30 Mon, 01 Jan 2018 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/43622 2018-01-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/43621 Title: Evaluation of fermentation kinetics of xylose to ethanol fermentation in the presence of acetic acid by <em>Pichia stipitis: </em> Modeling and experimental data comparison Authors: Kashid, Mohan; Ghosalkar, Anand Abstract: Acetic acid is one of the main inhibitor that shows negative impact on kinetics of sugar fermentation in the presence of <em>Pichia stipitis. </em> Unstructured kinetic model has been formulated that describes cell mass growth and ethanol production as a function of ethanol, oxygen, xylose and acetic acid concentration. Experiments have been carried out in batch mode with the acetic acid concentration varying from 3 to 12 gL^-1. Kinetic parameters are estimated for <em>Pichia stipitis</em> with various operating conditions of fermentation. Among all the kinetic parameters a great reduction in &mu;_MAX and increase in Y_P/X has been observed, which strongly affect the fermentation kinetics. Acetic acid presence in the fermentation lead to significant reduction in the maximum cell biomass concentration, reduction in xylose consumption rate, improvement in ethanol metabolic and reduction in ethanol production rate. This model describe physiological properties of PSA30 strain of <em>Pichia stipitis </em> and proposed models can be used to predict the influence of xylose, ethanol and acetic acid on cell growth and ethanol productivity in industrial fermentation. Page(s): 31-39 Mon, 01 Jan 2018 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/43621 2018-01-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/43620 Title: Preparation and characterization of Scallop shell coated with Fe₃O₄ nanoparticles for the removal of azo dye: Kinetic, equilibrium and thermodynamic studies Authors: Mohagheghian, Azita; Vahidi-Kolur, Robabeh; Pourmohseni, Melina; Yang, Jae-Kyu; Shirzad-Siboni, Mehdi Abstract: In this study, Scallop shell-Fe₃O₄ nanoparticles have been used as adsorbents for investigation of the adsorption kinetics, isotherms and thermodynamic parameters of the Acid Red 14 (AR14) from aqueous solutions at various <em>p</em>H, dye concentrations, adsorbent dosages, temperatures and ionic strength. Scallop shell-Fe₃O₄ nanoparticles are synthesized by co-precipitation method in vacuum condition. Efficient coating of Fe₃O₄ nanoparticles onto Scallop shell is identified by FT-IR, XRD, SEM, EDX and VSM analysis. Removal efficiency of AR14 by Scallop shell-Fe₃O₄ nanoparticles is greater than that by Scallop shell-alone and Fe₃O₄-alone. Maximum adsorption is observed at acidic condition. The removal efficiency of AR14 increased with increasing adsorbent dosage, but decreased with increasing initial AR14 concentration and temperature.The adsorption capacity of AR14 onto adsorbent is little affected by the type of ionic strength except carbonate ion. In kinetic studies, removal rate is better described by the pseudo-second order model than the pseudo-first order model and intra-particle diffusion model. Adsorption isotherm is analyzed by both Langmuir and Freundlich equation. Experimental results reveal that the adsorption reaction is exothermic process. Adsorption efficiency of AR14 by Scallop shell-Fe₃O₄ nanoparticles is maintained even after six successive cycles. Page(s): 40-50 Mon, 01 Jan 2018 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/43620 2018-01-01T00:00:00Z