the influence of surface roughness magnitude and direction on dry static friction coefficient between two similar steel samples has been studied through an experiment. a testing apparatus has been designed and fabricated to measure the friction coefficient for a few forms of surface asperity. according to the results of the experiments, dry friction coefficient is affected by both magnitude and...

nowadays cmm machines are widely used in surface measurement and inspection. as inspection results from cmm machine are obtained by the means of measuring surfaces with direct contact, they are more precise than non-contact method (like optical measurement). however, cmm machines give more reliable and accurate results rather than non-contact methods but also these results come with error when ...

conclusions potato peels were proved to be potentially useful substrates for biosurfactant production by b. pumilus dsvp18. the strain possessed a unique property to reduce surface tension of the media from 72 to 28.7 mn/m. in addition, it showed a stable surface activity over a wide range of temperatures, ph, and saline conditions and had strong antimicrobial activity. this potential of the id...

nanoparticles made of biodegradable polymers has become the best approach for nanoparticle making due to their compatibility with the human body. new glycerol adipate polymers with hydroxyl group substituted with different percent of acyl group, sited as figures within the abbreviated name in the text, and triptophan were synthesized and proposed to be used in the preparction of dexamethason ph...

there have been many productive methods developed so far for optimization of multiple response surface (mrs) problems. this paper tends to review the most seminal approaches in mrs and discuss the strength and weakness of each of the approaches through existing aspects in mrs. a numerical example is included to compare results by different methods. finally some of the prominent areas for future...

treated sea water is the most significant source of water and surfactant floods. the various chemicals employed in treatment plants should be compatible with surfactant systems. based on surface tension experiments, the activity of these chemicals is examined over a wide range of concentrations in different solutions, including distillated water, sea water by using three types of surfactant mix...