The present study modifies the sorption isotherm for simulating the influences of initial pH and temperature variations on the cadmium sorption from contaminated water using waste foundry sand based on Langmuir, Freundlich, and Temkin models. Results proved that the Langmuir expression is able to adopt these effects by relating sorption capacity and affinity constants with pH and temperature of aqueous solution through exponential relationships (determination coefficient = 0.9375). The present model is assumed that the sorption process occurs through acidic functional groups and this is consistent with FTIR outputs. Interaction of cadmium/WFS is found to be exothermic by thermodynamic analysis.

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In this study, a modulating model for solenoid magnetic field was presented. This model describes the on axis field through its hard edginess parameter as well as its axial half of half width at half peak field. The modulating model indicates to increasing the spherical aberration at the fields from real soft boundary to hard boundary modulating model. The investigation simply shows stay the peak field value constant at all order n, and the field sketch diverges to the hard boundary shape within high values of n > 60 and, as well the half of half width of field is (a) for all orders n < 6.

In the present work, the optimization by synthesis approach in the field of charged particle optics has been followed, where a modified analytical function has been proposed to represent the axial magnetic scalar potential distribution of the charged particle lens. Thereby, the corresponding axial field distribution can be deduced which is necessary to determine the paraxial ray trajectories and the aberration coefficients. Indeed, the present work deals with asymmetrical distributions of the lens field, accordingly, the first order properties and third order aberrations of the charged particle lens have been evaluated under zero and infinite magnification modes taken into account the effect of some geometrical parameters. The present work aims to reconstruct the shape of the pole piece of the magnetic lens that produced the proposed target function. The results have shown that, the pole piece shape of the lens and the field distributions have new irregular configurations as well as the objective properties of the lens are of acceptable values, according to the constraints that are imposed in the design process.

Concern over potential antimony mediated toxicity from mining and smelting activities has instigated novel concepts toward removing aqueous antimony ions. The iron based adsorbent Fe3O4/HCO was found to be efficient for treating antimony-containing wastewater However, ineffective methodology for preparation limited its effective adsorption capacity and thus wider application. In this study, a new type of HCO-doped-(Fe3O4)x adsorbent was prepared by co-precipitation method for doping Fe3O4 into HCO sludge (HCO), thereby improving adsorption performance for Sb(III) and Sb(V) ions, with the maximum adsorbing capacity being 44.46 mg/g and 47.91 mg/g, respectively. According to the results of BET, SEM-EDS, XRD and XPS, it were confirmed that the FeOOH and X&equiv;Fe-OH were formed during the preparation process, bring about the increased the surface area, thus resulting in further increase of surface area, hydroxyl groups and the net negative ionic charge. Moreover, the adsorption kinetics followed the pseudo-second-order kinetic model which indicated that adsorption process of Sb(III)/Sb(V) by HCO-doped-(Fe3O4)x adsorbent was controlled by chemical reaction. The main adsorption mechanism is that antimony ion and amorphous iron oxide X&equiv;Fe-OH undergo coordination exchange reaction and complexation reaction with CeO2 or Ce2O3. Furthermore, HCO-doped-(Fe3O4)x could adapt to wide pH and had stable adsorption ability after regeneration. The good adsorption performance of HCO-doped-(Fe3O4)x makes it a potential applications of adsorbent for removal of antimony.