We study compact stars with hybrid equations of state consisting a nuclear outer region and two nested quark phases, each separated from the lower density phase by strong first-order transition. The stability these models is determined calculating their radial oscillation modes different conversion rates between adjacent phases hence junction conditions for at separation interface them. In case...

Calcium oxide is one of the appropriate catalysts for biodiesel production. In this study, cheap and compatible with environment catalyst has been used. Mussel shell of Persian Gulf coast is one of the sources of calcium carbonate that is converted to calcium oxide at calcination temperature up to 950°C. Transesterification reaction was carried out at optimum condition of our previous study...

Pills of Mefenamic acid were  employed as effective catalysts in the three component reaction of aromatic  aldehydes,  malononitrile,  as  well  as  4-hydroxycoumarin  or  barbituric  acid  in  aqueous solution,  using  reflux  conditions  in  order  to  synthesize  derivatives  of  dihydropyrano[2,3-c]chromene and pyrano[2,3-d]pyrimidine, correspondingly. Among the benefits of this technique, ...

in order to gain a better understanding of the chemistry of methanl-to-hydro-carbon conversion, it is necessary to determine the nature of the primary reaction products. experiments carried out in this work on h-zsm-11, using a continuous flow reactor linked to an on-line gas chromatograph demonstrated that ethylene and methane are the primary reaction products. the results obtained using solid...

acetic acid has been applied as an efficient catalyst and a green solvent for the two–component condensation reaction consisting of benzaldehyde, 2-amino-benzamide. the advantages of this protocol was excellent yield, short reaction time, mild reaction conditions, higher availability, low costs, more environmentally friendly, lack of need for column chromatography and simple work-up procedure. ...

antranilic acid is an intermediate material which we can produce by hofmann's rearrangement reaction. in this process phithalimide is a main reactant. one procedure for produceing phthalimide is the reaction of phithalic anhydride with urea in the presence of acetic acid. in this research, the kinetics of this reaction was studied at 115 c. we found that the reaction of phthalic anhydride ...

leaching of molybdenite concentrate with hydrogen peroxide in sulfuric acid solution was investigated to determine the effects of reaction time, reaction temperature, h2o2 concentration, h2so4 concentration, pulp density and rotation speed on molybdenum extraction and molybdenite dissolution kinetics, using the taguchi method. from analysis of variance (anova) for molybdenum extraction, the mos...