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981.
Sambhav Vora Mehul Khimani Chinmay De 《Journal of Dispersion Science and Technology》2013,34(7):947-956
The adsorption of cationic dye, Basic Red 13 from aqueous solution onto silica has been studied. The time growth adsorption as a function of the amount of adsorbent, pH, initial dye concentration as well as the temperature was measured of the system. Adsorption was found to follow a first-order process. Various isotherm and thermodynamic parameters for the adsorption of dye have been calculated. Isotherms were used to identify formation of either monolayer or multilayer formation whereas thermodynamic and other parameter indicated that the dye adsorption process was physisoption as well as spontaneous and exothermic in nature. 相似文献
982.
The conductometric measurements were employed to determine the critical micellar concentration (CMC), degree of dissociation and dissociation constant of dilute solutions of Gadolinium decanoate and dodecanoate in benzene and methanol mixture (7:3 v/v). The results show that the Gadolinium alkanoates behave as moderate electrolyte below the CMC. The various thermodynamic parameters were also evaluated for both dissociation and association process. 相似文献
983.
Ahmed M. Al-Sabagh Nadia G. Kandile Rasha A. El-Ghazawy 《Journal of Dispersion Science and Technology》2013,34(7):996-1007
In the present study, five types of water soluble demulsifiers based on linear alkyl benzene were prepared. The chemical structures of the prepared demulsifiers were elucidated using Fourier transform-infrared (FTIR) and 1H NMR spectra. Different factors affecting demulsification efficiency such as; water content, demulsifier concentration, hydrophilic lipophilic balance (HLB), and ethylene oxide unit were investigated. Also, the rheological properties in relation to demulsification efficiency were studied. The surface and thermodynamic parameters of the prepared demulsifiers were determined at 25°C including, surface tension (γ) and effectiveness, maximum surface excess (Γmax), and minimum surface area (Amin). From the obtained data, it was found that the demulsification efficiency increases with increasing the water content and concentration of the demulsifiers. Primarily evaluation study of demulsification performance of the new demulsifiers showed that as the ethylene oxide unit in the demulsifiers increase (10–40 ethylene oxide units), the performance of the demulsifiers increasing, however, it decrease in case of demulsifiers with (80 ethylene oxide unit). 相似文献
984.
Nermin E. Maysour 《Journal of Dispersion Science and Technology》2013,34(8):1287-1298
Poly (ethylene terephthalate), PET, waste was recycled to oligomers in the presence of triethanolamine and manganese acetate as a catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol having different molecular weights 400, 1000, and 4000 to produce nonionic polymeric surfactants having different hydrophile‐hydrophobe balances (HLB). The surface tension, critical micelle concentration (CMC) and surface activities were determined at different temperatures. Surface parameters such as, surface excess concentration Γmax, the area per molecule at interface Amin and the effectiveness of surface tension reduction (ΠCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process are calculated and discussed. 相似文献
985.
Recycling of PET waste was carried out in presence of diethanolamine and manganese acetate as catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol, PEG, which have different molecular weights 400, 1,000, and 4,000 to produce nonionic polymeric surfactants having different hydrophilic‐hydrophobic balance (HLB). The surface tension, critical micelle concentration (CMC), and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration Γmax, the area per molecule at interface Amin and the effectiveness of surface tension reduction (ΠCMC) were determined from the adsorption isotherms of the prepared surfactants. From the adsorption isotherm, some thermodynamic data for the adsorption process are calculated and discussed. 相似文献
986.
The interfacial composition, thermodynamic properties and structural characteristics of [bmim][BF4] + CTAB + alkanol + toluene microemulsions were studied by the method of dilution under varied temperatures (298 K, 308 K, 318 K). The compositions of surfactant and cosurfactant at the interfacial region, the distribution of cosurfactant between the interfacial region and the continuous oil phase have been estimated. The thermodynamics of transfer of cosurfactant from the continuous oil phase to the interface have been evaluated. The structural parameters viz. radii of the droplet (R e) and the ionic liquid pool (R IL), the thickness of the interfacial layer (l), the number of droplets (N d) have also been estimated assuming monodispersity of the spherical droplets. 相似文献
987.
We have developed a novel vertical-alignment (VA)-π cell mode that provides a wide viewing angle and fast response times for a negative dielectric anisotropy nematic liquid crystal on homeotropic polyimide surfaces. Good voltage-transmittance curves and low driving voltages were achieved with the novel VA-π cell mode without negative compensation film. Iso-viewing angle characteristics were also successfully observed. A fast response time of 31.7 ms for the novel VA-π cell mode was also measured. 相似文献
988.
Živković D. Živković Ž. Yonghua L. Chou K. C. 《Journal of Thermal Analysis and Calorimetry》2001,66(3):785-793
Results of the comparative thermodynamic analysis of the Pb-BixMgySbz section (x:y:z=8:1:1, in mole ratio) in the Pb-Bi-Mg-Sb system, obtained experimentally by Oelsen calorimetry and predicted by general solution
model in the temperature range 600–1100 K, are given in this paper.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
989.
990.