Ionic Liquid Modified Resin for the Adsorptive Removal of Dibutyl Phthalate: Equilibrium,Kinetic, and Thermodynamic Studies     

Umair A. Qureshi  Amber R. Solangi  Saima Q. Memon  Syed I. H. Taqvi  Najma Memon 《洁净——土壤、空气、水》2012,40(6):630-639

This study evaluated the adsorptive properties of dibutyl phthalate (DBP) on room temperature ionic liquid (RTIL) modified XAD‐4 resin. The modified RTIL‐XAD 4 sorbent was characterized by FTIR. Effect of varying experimental conditions such as pH, contact time, temperature, shaking speed, concentrations, and interfering species were investigated by batch adsorption experiments. Adsorption was found to be most favorable at pH 6 within 30 min. Experimental data were evaluated in terms of kinetic, equilibrium, and thermodynamic modeling. Kinetics of the sorption was found to follow pseudo second order rate equation whereas Freundlich and D–R isotherms were the most suitable models to explain sorption phenomenon. Thermodynamically sorption was endothermic, irreversible, and spontaneous in nature.  相似文献   

Pore pressure coefficient B for saturated geomaterials with compressible,isotropic and uniform solid and fluid phases     

Szalwinski  Chris M.  Najma  Alireza  Sharma  Jitendra 《Acta Geotechnica》2020,15(8):2103-2115

  相似文献   

Predicting flow liquefaction,a constitutive model approach   总被引：1，自引：1，他引：0  

Alireza Najma  Manouchehr Latifi 《Acta Geotechnica》2017,12(4):793-808

In this paper, flow liquefaction criterion for contractive loose sands is analytically extracted based on the fundamental definition of flow liquefaction. In order to obtain the closed form of this criterion, Dafalias–Manzari constitutive model is employed; so the stress ratio at the onset of flow liquefaction is presented as a function of model parameters, state parameter and void ratio. Flow liquefaction line, as a graphical form of suggested criterion in stress space, shows that the peak points of undrained stress paths with same void ratios are not necessarily in a straight line. In order to validate the reliability of proposed flow liquefaction line to predict the onset of instability, it has been compared with the results of experimental tests performed on Toyoura, Ottawa and Leighton Buzzard sands. The verification results show that the present criterion can satisfactorily predict the onset of flow liquefaction in monotonic and cyclic undrained tests of saturated sands as well as the structural collapse in constant deviatoric stress tests of loose dry sands.  相似文献