The main objectives of this work are: (1) to explore and improve the hybrid CO2 laser/waterjet (LWJ) technique, developed by Iowa State University’s Laboratory for Lasers, MEMS and Nanotechnology, to machine thick polycrystalline cubic boron nitride (PCBN) tool blanks both in 1D and 2D with minimum energy consumption and good cut quality; (2) to examine the mechanism of crack separation in the ...

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...

bacillus subtilis k40b was isolated from rice rhizospheres and its potential for production of xylanase was evaluated using biochemical methods. the gene for xylanase in b. subtilis k40b was amplified, sequenced and assigned to the ncbi genebank. the gene size was estimated to be 563 bp encoding 413 amino acids. comparison of the xylanase gene with reference sequences showed that the xylanase o...

In this research, Response Surface Methodology (RSM) is used to investigate the effect of four controllable input variables namely: discharge current, pulse duration, pulse off time and applied voltage Surface Roughness (SR) of on Electrical Discharge Machined surface. To study the proposed second-order polynomial model for SR, a Central Composite Design (CCD) is used to estimation the model co...