formaldehyde in small quantities is commonly analyzed by spectrophotometric methods. one of the most-commonly used spectrophotometric techniques for this purpose is based on the reaction with chromotropic acid. because of its simplicity, sensitivity, selectivity and its low cost, it is still widely used. investigations for replacing the concentrated sulfuric acid with other acids or using more ...

a box-behnken design with three replicates was used for preparation and evaluation of eudragit vancomycin (vcm) nanoparticles prepared by double emulsion. the purpose of this work was to optimize vcm nanoparticles to improve the physicochemical properties. nanoparticles were formed by using w1/o/w2 double-emulsion solvent evaporation method using eudragit rs as a retardant material. full factor...

a rhamnolipid–type biosurfactant production by pseudomonas aeruginosa mm1011 was studied in a miniaturized shaken bioreactor. the operational parameters, affecting the biosurfactant production in shaken bioreactors, such as shaking frequency (200, 250, 300 rpm), filling volume (50, 75, 100 ml), and aeration rate (0.2, 0.6, 1 vvm), were optimized using response surface methodology. the optimizat...

environmental pollution by 2,4-dicholorphenol (2,4-dcp), commonly found in industrial wastewater has been a concern for humans over the past 50 years. garden radish peroxidase (grp) can eliminate this poisonous pollutant. the aim of this study was to apply an experimental response surface methodology (rsm) and central composite design (ccd) to optimize grp-based treatment in order to maximize ...

in this study fullerene functionalized using oleum (h2so4·so3), followed by the hydrolysis of the intermediate cyclosulfated fullerene as well as  an oxidizing agent was employed to functionalize the fullerenes. ruthenium was then added by the impregnation method or deposited on the functionalized fullerene. subsequent to this step, response surface methodology (rsm) was used to study the cumul...

   In this work, magnetic graphene oxide (MGO) was prepared by in situ synthesis of magnetite nanoparticles in the presence of graphene oxide (GO). The prepared nanocomposite was characterized by applying scanning electron microscopy (SEM), X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer (VSM). MGO was applied as an ...

Microcystin leucine-arginine (MC-LR), is a hepatotoxic agent produced by cyanobacteria, capable of posing serious threat to the human and ecological environment. In this study, bismuth vanadate (BiVO4)/NaY-Zeolite nanocomposite was intended for degradation MC-LR in aquatic solutions. The response surface methodology (RSM) used optimize operating variables affecting removal. results showed that ...

ultrasound-assisted extraction was used to determine the optimum processing conditions and to achieve the maximum extraction yield and viscosity of the gum extracted from quince seed. using response surface methodology (rsm) to design the experiments and adopting the central composite rotatable design (ccrd), the effect of extraction temperature (25-55°c), time (3-10 minutes), and ph (6-8) were...

In the present work, the optimization of different structural and process parameters of a divided wall column (DWC) for the energy efficiency has been presented. The optimal design and operation of divided wall distillation columns involve a number of variables and is a non-linear problem. Rigorous simulation of a DWC was carried out using Multifrac model of ASPEN Plus software. Box–Behnken des...

In this study, extraction of amoxicillin (AMOX) ions from aqueous solution by liquid-liquid extraction (LLE) was investigated. The LLE process by response surface methodology (RSM) was carried out based on central composite design (CCD). The organic phase consisted of extractant and toluene as diluent. In this process, triethylamine (TEA), di-2-ethylhexyl phosphoric acid and mono-2-ethylhexyl p...