in this study chemical method of dissolution-precipitation was applied to produce amorphous silica nanoparticles from rice straw ash (rsa), the waste material of rice cultivation. the morphology, particle size, structure and area of specific surface of synthesized amorphous silica nanoparticles were evaluated using transmission electron microscopy (tem), x-ray diffraction analysis (xrd) and bet...

The increase of combination number according to the variables is a serious problem in using section optimization for steel structures. Response Surface Method (RSM) which uses approximate functions made by sampling data was proofed as one effective methods. This paper shows features proposed method that combined with genetic algorithm applying it allowable stress design middle rise structure an...