in this study, sio2 nanoparticles were successfully synthesized via sol-gel precipitation method and the effects of different parameters such as temperature, ethanol, ammonia and tetraethylorthosilicate (teos) contents based on water were investigated in a systematic way applying taguchi experimental design method. it was found that, among all the investigated parameters, ethanol as a co-solven...

tehran is located in a valley at the foot of the alborz mountains in northern iran (35 degrees latitude north). urban expansion in tehran resulted from a high rate of population growth and rural-urban migration combined with a strong tradition of centralization in the capital. airborne particulate of tehran's atmosphere was fractionated in a 6-stage high-volume cascade impactor. the first ...

background : this research provides an insight into exposure information and particle size distributions of bisphenol a (bpa), a common environmental hormone, at polycarbonate (pc) molding plants in southern taiwan. methods : the inhalable dust sampler as iom and the micro-orifice uniform deposition impactor (moudi) were used for samples collection to evaluate the level and particle size distri...

as a native fermented dairy drink, doogh is an important industrial product in iran. however, its characteristics have not been completely evaluated. this study evaluated the flow behavior, particle size distribution and stability of non-fat doogh as affected by the row material employed (fresh skim milk or skim milk powder) and the total solids (ts) content of the final drink. the viscosity of...

the design of cement slurry for horizontal wellbores is challenging as it must present very high quality cement slurry properties e.g. zero free water, less than 50 cc api fluid loss value, appropriate rheology and yield point for effective displacement, adequate compressive strength, which is critical for lightweight slurries, and finally stable cement column behind casing. the main objective ...

the benefits of using mineral admixtures as a partial replacement of portland cement (pc) are well established in the literature. economic and environmental advantages by reducing co2 emissions are well known. this paper examines the influence of intergrinding and separate grinding on the amount of energy consumption, blaine fineness and particle size distribution (psd) of blended cements, name...

introduction: particle size and distribution can influence the properties of materials. this study analyzed and compared the particle size of root mta, calcium hydroxide (ch), and a new endodontic cement called calcium enriched material (cem). materials and methods: the particle size of each material was analyzed three times using 0.05 mg of test material with a particle size analyzer. the part...

quantum dots of cds with hexagonal phase were prepared at relatively low temperature (60 oc) and short time by micro-emulsion (o/w) under ultrasound. this study was focused on the particle size distribution and the growth kinetics. the particle size distribution obtained from the optical absorption edge. it was relatively symmetrical with sonication time. in addition, an agreement was observed ...