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...

the study describes the synthesis and characterization of zinc(ii) minoxidil nanocomposite (1). the reaction between zinc(ii) acetate, minoxidil, {c9h15n5o=minoxidil=(2,4-diamino-6-piperidine-1-yl) pyrimidine n-oxide)} as a ligand and ki as bridging agent, in methanol at 60°c leads to the formation of nano-sized zn(ii) minoxidil nanocomposite, 1. characterization of (1) was carried out by eleme...

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 ...

Gas phase polymerization of propylene was carried out in a semi-batch minireactor using a commercially supported Ziegler–Natta (ZN) catalyst. The influence of variables including monomer partial pressure, external electron donor, reaction temperature and time on the particle morphology and size distribution was investigated. Generally, more uniform fragmentation and particle densities were obta...

stoichiometric tetragonal bal-xsrxtio3 (x = 0.23) nanopowders were prepared by stearic acid gel(sag) method using barium stearate, strontium stearate, tetrabutyl titanate as ba, sr, ti sourcesand stearic acid as complexing reagent. thermal analysis including differential thermogravimetric(dtg) and tg, fourier transform infrared spectrometry (ftir), x-ray diffraction (xrd) andtransmission electr...

benzoyl peroxide (bpo) is a first-line topical treatment in acne vulgaris, and it is superior to antibiotics, because the bacteria do not develop resistance to it. skin irritation is a common side effect, and it has been shown that controlled release of bpo from a delivery system to the skin could reduce the side effects while reducing percutaneous absorption. therefore, the purpose of the pres...

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...

nanocomposite of zro2/zno was prepared under ultrasonic irradiation by sol gel process from directly mixing zirconium and zinc gels, and the mixture was placed under ultrasonic irradiation for 2 hours then aging time the filtrated composite gel was calcinated at 500°c for 3h in furnace. the precursor sol of zirconium was prepared from an aqueous solution of zrcl4 and zinc acetate dihydrated was...

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 ...