The removal of any pollutant by Commercial Activated Carbon is highly practiced one. But in this study, manganese (II) ions by adsorption on Prosopis Juliflora Carbon (PJC) and comparison with Commercial Activated Carbon (CAC) have been made at 30±1°C under batch mode. The removal data on the variation of (i) initial concentration of manganese (II) ions, (ii) initial pH of the solution are determined, (iii) amount of material and (iv) contact time. The percentage removal of manganese (II) ions increased with the decrease in initial concentration and increased with the increase in contact time, the amount of adsorbent (PJC and CAC) and initial pH of the solution. Adsorption data have been analyzed with the help of adsorption kinetics. The observed RL value is 0-1 (0.102) and the correlations of log q vs log (dose) are also found to be linear with r-value close to unity (r value = 0.946 and 0.979) and after 90 minutes of contact time, the increase in the percentage removal of Mn (II) ions is not significant. The limiting factor involved in the study is intraparticle diffusion. In the current research it is found that PJC could be used as an alternate adsorbent material in the removal of metal ions, in general and manganese (II) ions, in particular.
In this study, a biosorbent was successfully applied to remove thorium metal Th(IV) from aqueous solutions. Moringa oleifera bark was fractionated into 60-mesh particles to perform characterization and extraction experiments. The adsorption kinetics for Th(IV) followed a pseudo second-order model, and small difference between the experimental and calculated Qeq values [4.38 and 3.32 mg/g for Qeq(exp.) and Qeq(cal.), respectively] was observed. The maximum capacity (Qmax) value calculated using the modified Langmuir equation 5.46 mg/g.
Three rapid, accurate and sensitive visible spectrophotometric methods for the assay of tobramycin sulphate have been development. Method A (λmax; 470 nm) is based on the reaction of tobramycin with 3-methyl-2-benzothiazolinone hydrazone hydrochloride in the presence of ceric ammonium sulphate. Method B (λmax; 505 nm) involves the reaction with p-dimethylaminobenzaldehyde in presence of sulphuric acid and ferric chloride. Method C (λmax; 579 nm), is based on the formation of a coloured ion-pair complex between tobramycin and rose bengal. All variables have been optimized and the reaction mechanisms presented. Regression analysis of the Beer’s plots showed good correlation in concentration ranges 1.0-12, 1.5-30, and 3.5-71 μg/mL for method A, B, and C, respectively. No interferences were observed from excipients and analyzing pharmaceutical dosage forms containing tobramycin tested the validity of the methods. The relative standard deviations were within 1.42%. For more accurate results, Ringbom optimum concentration ranges are 1.5-11, 3.0-27, and 7.0-68 μg mL, respectively. The apparent molar absorptivity, Sandell sensitivity, detection and quantification limits are also calculated.
The density functional pseudopotential simulation was used to study dissociation of an H2O molecule on the anatase TiO2 surface (undoped and W, Cr, V or Mo doped). Desorption of the OH group was studied, and it was shown that the doping of W, Cr and V atoms into titanium dioxide leads to reduction of the desorption energy of the OH radical that can increase efficiency of photocatalytic reactions in water. Molybdenum does not affect the desorption features of the OH group.
Surface active agents (surfactants) are among the most versatile chemicals used in various areas and known to play an important role in many processes of interest; in fundamental and applied science, such as cleaners, paints, cosmetics, pharmaceuticals, food, medicine and biochemical research. Over the years, the use of surfactants has increased considerably. Especially, the use of surfactants with different roles in sample-preparation methodologies is a great contribution to minimizing the problems arising from pre-processing or primary production processes such as recovery, purification of raw materials or to enhance quality of finished products such as an emulsifier, an extraction medium, solubilizing agent and excipients in pharmacy. In addition to these properties, surfactant micelles provide an attractive model system for bio-membranes. Knowledge and understanding of surfactant systems have led to the development of successful models to provide useful information for industrial applications. This mini review has been intended to provide information and general references of surfactants used in the field of pharmacy and presented under forth sections: i) surfactants commonly used in pharmacy and pharmaceutical applications ii) micellar binding of drugs and interactions iii) micellar solubilization iv) surfactants in drug delivery.