To Study the Significance of Processing Variables Using Quality by Design for Optimization of Nanoparticulate System of Cilnidipine

This investigation aimed to prepare Cilnidipine Nanoparticles by nanoprecipitation ultrasonication method and to study the significance of processing variables by applying quality by design. Cilnidipine is fourth-generation dual L/N-type Ca2+ channel blocker used for the management of hypertension. It is BCS class-II drug exhibiting lower aqueous solubility, which tends to lower bioavailability. The combination of Poloxamer 188 and Tween 80 was used as a stabilizer. The design of the experiment is one of the tools of Quality by design. Plackett-Burman design was applied for the screening of processing variables, which are significant for the method. The processing variables screened were stirring speed, antisolvent ratio, drug concentration, polymer concentration, stabilizer concentration. The effect of each parameter evaluated by particle size, entrapment efficiency, and drug release at 10 minutes of prepared Nanoparticles of Cilnidipine. Analysis of variance and Pareto-plot of Plackett-Burman design were utilized to find the significance of the factor and extent of the effect. The surface morphology of Cilnidipine Nanoparticles was studied by SEM. The Pareto plot, as well as statistical analysis of design, had shown that the Concentration of drug, solvent: antisolvent ratio and concentration of poloxamer 188 were the significant parameters for the method. The stabilizer concentration, the stirring speed, and the antisolvent ratio had a negative effect of while the concentration of drug has a positive effect on the particle size of Nanoparticles and drug release at 10 minutes and positive effect of entrapment efficiency of Cilnidipine Nanoparticles. The Cilnidipine Nanoparticles were characterized by FTIR and DSC analysis.

Removal of gas-phase benzene in an immobilized photocatalytic reactor

The photocatalytic degradation of gas-phase benzene was studied in an immobilized – annular tube reactor using titanium dioxide as the photocatalyst. The main and interaction effects due to the influence of essential process parameters such as catalyst load (5 to 20 g·m–2), benzene concentration (0.2 – 3.1 g·m–3) and flow rate (0.2 to 1 l·min–1 corresponding to residence times of 14 s and 70 s respectively) on the removal of benzene were investigated, by carrying out experiments that were designed to express statistical significance. The main effects plot and Pareto plot provided good insight into the effect of different parameters on the removal of gas-phase benzene. A new, statistical measurement suggests that low gas–phase benzene concentration is more important for maintaining high removal efficiencies (96 %) in the photocatalytic reactor than both catalyst load and flow rate.

Optimum Design of a Compliant Uniaxial Accelerometer

This work focuses on the multi-objective optimization of a compliant-mechanism accelerometer. The design objective is to maximize the sensitivity of the accelerometer in its sensing direction, while minimizing its sensitivity in all other directions. In addition, this work proposes a novel compliant hinge intended to reduce the stress concentration in compliant mechanisms. The paper starts with a brief description of the new compliant hinge, the Lamé-shaped hinge, followed by the formulation of the aposteriori multi-objective optimization of the compliant accelerometer. By using the normalized constrained method, an even distribution of the Pareto frontier is found. The paper also provides several optimum solutions on a Pareto plot, as well as the CAD model of the selected solution.

Optimum Design of a Compliant Uniaxial Accelerometer

This work focuses on the multi-objective optimization of a compliant-mechanism accelerometer. The method is used to optimally design an accelerometer with the architecture of a novel version of the Sarrus mechanism. The purpose is to maximize the sensitivity of the accelerometer in its sensing direction, while minimizing its sensitivity in all other directions. The paper starts with a brief description of the dynamics model of the compliant mechanism, followed by the formulation of the a posteriori multi-objective optimization. By using the normalized constrained method, an evenly distribution of the Pareto frontier is found. The paper also provides several optimum solutions on a Pareto plot, as well as the CAD model of the selected solution.