esterification of chitosan with adipic acid catalyzed by immobilized candida antarctica lipase b was carried out in this study. response surface methodology (rsm) based on a four-factor- five-level small central composite design (sccd) was employed to model and analyze the reaction. a total of 21 experiments representing different combinations of the four reaction parameters including ch...

vanadium phosphorus oxides (vpo) has been applied as a heterogeneous catalyst in gas phase oxidation reactions and its application is very limited in liquid phase. in this study a series of cobalt-doped vanadium phosphorus oxides (vpo-co) catalysts with different loading of co (0.01-1.0 mol ratio of co/v) were prepared. oxidation of benzyl alcohol was studied in the liquid phase over vpo and vp...

in this paper, size distribution of nano-bubbles was measured by the reliable and fast method of laserdiffraction technique. nano-bubbles were produced using a nano-bubble generator designed and madebased on hydrodynamic cavitation phenomenon in venturi tubes. a central composite design withresponse surface methodology was used to conduct a five factor, five level factorial experimental designo...

in this present study the dissolved air flotation (daf) system was investigated for the treatment of kermanshah oil refinery wastewater. the effect of three parameters on flotation efficiency including of flow rate (outflow from the flotation tank), saturation pressure and coagulant dosage on chemical oxygen demand (cod) removal was examined experimentally. all the experiments were done under a...

in order to reduce the costs associated with poly-β-hydroxybutyrate production, growth and poly-β-hydroxybutyrate production of ralstonia eutropha were studied in batch culture on different carbon sources. experiments were designed and conducted to not only lower the cost of poly-β-hydroxybutyrate production by using inexpensive substrates, but also to increase poly-β-hydroxybutyrate production...

the impact resistance of new lightweight panel is studied. this panel consists of two thin metal layers bonded together by intermediate fiber/epoxy layers (mcm-sheets). to simulate a behavior of this kind of impact problem, explicit and implicit finite element software abaqus is used. in order to validate the finite element modeling, these results have been compared with experimental test resul...

in the present study, the effects of four factors including initial sulfide concentration (mg l-1 ), agitation speed (rpm), amount of inoculums (%) and sodium concentration (mg l-1) on removal efficiency (%r) and yield of sulfate production by thioalkalivibrio versutus from synthetic spent caustic were investigated. for this purpose, experiments are designed by design of experiments (doe) and r...

background: application of potassium ferrate is a chemical oxidation approach used for water and wastewater treatment. the aim of this study is to apply central composite design (ccd) and response surface methodology (rsm) to optimize potassium ferrate consumption in the treatment of wastewater from carpet industries. methods: samples in this experimental study were collected from wastewater, o...

anodic aluminum oxide (aao) fabricated by two step anodization technique, is used as a template to synthesize feco nanowire arrays by ac electrodeposition technique. response surface methodology (rsm) is applied to design the experiments, fit an empirical model and optimize the conditions to achieve the best magnetic properties. the magnetic properties, pore dimensions, composition and structur...

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 t...