in our current study, supercritical water impregnation (scwi) was introduced as a unique catalyst preparation method by employing the high diffusivity property of supercritical water. the method allows nano-particles to place on support surfaces in extremely dispersed conditions. the silica-based nanocatalyst granules for this purpose were prepared by initial impregnation of highly porous silic...

gold nanoparticles were synthesized by chemical reduction of haucl4 inside the pores of a polycarbonate-based membrane followed by dissolving the membrane in dichloromethane and further sonication. sonication time as the main affecting factor on the nanoparticle size was investigated. the characterization by transmission electron microscopy showed the formation of gold nanoparticles with diamet...

a novel modified ni-zsm-5 nanozeolite was fabricated via an organic template-free hydrothermal route. the average particle size of ni-zsm-5 nanozeolite was calculated to be 85 nm by scanning electronic microscopy. then, carbon paste electrode (cpe) was modified by ni-zsm-5 nanozeolite and ni2+ ions were then incorporated to the nanozeolite matrix. electrochemical behavior of this electrode was ...

Zeolite ZSM-5 presents a great source of interest in catalysis because of its shape selective properties. The absence of a relationship between the template size and shape of the structure generated during the synthesis of zeolites is illustrated by the case of ZSM-5. In this study, we have investigated the role of ethanol, methyltriphenylphosphonium bromide (MTPBr) and cetyltrimethylammonium b...

Two approaches for metal ion incorporation were employed to introduce Ca2+ into SBA-15; Direct Synthesis (DS) and Wet Impregnation (WI). The non-ionic template was removed by two different methods; calcination and solvent extraction. The obtained catalysts were characterized by means of X-Ray Powder Diffraction (XRD), Energy Dispersive X-ray (EDX), and FT-IR spectroscopy. The bas...

zeolite zsm-5 presents a great source of interest in catalysis because of its shape selective properties. the absence of a relationship between the template size and shape of the structure generated during the synthesis of zeolites is illustrated by the case of zsm-5. in this study, we have investigated the role of ethanol, methyltriphenylphosphonium bromide (mtpbr) and cetyltrimethylammonium b...

oxide nanoparticles can exhibit unique physical and chemical properties due to their limited size and a high density of corner or edge surface sites. in this study, mgo nanoparticle was synthesized using mg(ch3coo)2 and hexamethylenetetramine as starting materials. the structure and optical properties of these particles are investigated by using x-ray diffraction (xrd), scanning electron micros...

The article discusses differences between a priori and a posteriori phrasing and their importance in the task of automatic prosodic phrasing in text-to-speech systems. On several examples it illustrates shortcomings of common evaluation of a priori phrasing performance using a posteriori phrasing of referential corpus data. The paper also proposes and evaluates a method for a priori phrasing ba...