One of the key influencing parameters in the safe management of nuclear waste repositories is the distribution coefficient ( ) of radionuclides on bedrock. In this study,  of uranium and thorium ions in intact bedrock were determined using BATCH EXPERIMENTS on crushed bedrock at seven different particle size fractions as well as three different initial concentrations of ions. Sorption EXPERIMENTS have been performed on crushed bedrock prepared from intact drill core samples and an aqueous solution containing desired ions from the local water (LW) near Anarak Nuclear Waste Repository. The results showed that both factors of the initial ions concentration as well as the size of the crushed bedrock particles significantly affect the value of the distribution coefficient so that (  value increases with decreasing particle size and increasing ion concentration. Also, ( calculated at three studied concentrations showed that the difference in the ( values in smaller particles is large but decrease with increasing particle size and ( ) curves for two concentrations of (100 and 10) ppm overlap at the end of the chart. Therefore, it can be concluded that for accurate calculation, it is better to use large particles and low concentrations of ions to determine ( ) in intact bedrock. In this report, different mechanisms including chemical interactions, physical adsorption, and ion exchange were presented for ion adsorption by bedrock. The proposed mechanisms were related to the type of metal speciation of ions in the solution. Based on the obtained data, the preferred mechanism to describe the adsorption of uranium and thorium ions is composed of chemical interactions and physical adsorption.

This study reports the usage of chemically impregnated coconut coir waste (CICCW) as a low-cost adsorbent for the desulfurization of feed diesel. The characterization of the developed adsorbent was focused on quantitative analysis (carbon yield %, proximate, ultimate, carbon surface functionalities, BET surface area and porosity distribution, and particle size analysis), qualitative analysis (FTIR), and optical analysis (SEM). BATCH EXPERIMENTS with feed diesel having a total sulfur concentration of 2,050 mg L-1 were conducted to optimize the adsorption parameters such as adsorbent dose, temperature, and contact time. The adsorption process shows an optimum dose of 1 g/20 mL, and the equilibrium is attained in 3 h. The adsorption of sulfur onto the adsorbent at optimum temperature 293 K is regulated by external mass transfer (diffusion into mesopores) followed by a steady adsorption phase with intra-particle diffusion in micropores. A Fickian mechanism controls the diffusion of sulfur molecules from the solution onto the surface of the adsorbent. Freundlich adsorption isotherm illustrates the equilibrium adsorption data very well. The negative value of ΔGo (-27.61 kJ mol-1) and ΔSo (-44.56 J K-1 mol-1) indicates the feasibility, spontaneity of the adsorption process and justified the decrease in the randomness of adsorbed sulfur molecules onto the adsorbent surface, respectively. The exhausted CICCW can be effectively regenerated by methanol and reutilized for three adsorption–desorption cycles. The approximate cost of preparation of the adsorbent was USD 10.714 per kg. These results clearly proved the feasibility of the developed low-cost adsorbent (CICCW) as a good candidate for the desulfurization of feed diesel.

BATCH sizing in different planning period is categorized as a classical problem in production planning, that so many exact & heuristic methods have been proposed to solve this problem, each of which considering various aspects of the original problem. The solution obtained from majority – e.g. MRP – is in this format that there may be some periods of idleness or each period should produce as needed in different adjacent periods. If there are more the one final independent product to be produced in a factory, this makes the production planning experience strong variations in BATCH sizes for different periods, which production managers are opposed to these proposed production plans. In this paper, some of the models are proposed to solve this shortcoming of the production plan to smooth the variation of BATCH sizes and consequently to meet the managers ideal. Finally all of the proposed models are used in a real case problem and the best model is introduced in that case.

The present study explores the effectiveness of Typha domingensis leaf powder for simultaneous removal of aluminium, iron, zinc and lead ions from aqueous solution. BATCH EXPERIMENTS were carried out in laboratory at room temperature and at initial ions concentrations simulating the concentrations of these cations in real wastewater samples. The sorption process was examined applying the first and second order kinetic mechanisms. The results were best described by the second order rate kinetics. The applicability of the three equilibrium isotherm models was investigated. The obtained data follow the three investigated isothermal models in the following order: Langmuir > Freundlich > Temkin, for all the studied metal ions. The infrared spectra of native and exhausted Typha leaf powder confirmed ions-biomass interactions responsible for sorption. The results showed that Typha domingensis leaf powder can easily be envisaged as a new low cost natural biosorbent for metal clean up operations in aquatic systems.