Hollow nanostructures are paid increasing attention in many nanotechnology-related communities in view of their numerous applications in chemistry and biotechnology, e.g. as smart nanoreactors or drug-delivery systems. In this paper we consider irreversible, diffusion-influenced reactions occurring within a hollow spherical cavity endowed with a circular hole on its surface. Importantly, our mo...

The amount of carbon dioxide in the atmosphere is increasing continuously. Its accumulation in the air is one of the major causes of global warming and the change at equilibrium condition of weather and the environment. Utilization of carbon dioxide and other greenhouse gases to produce useful chemicals could be a suitable solution to this problem. CO2 is not just a greenhouse gas, but also an ...

in this study, pyrite was produced by hydrothermal precipitation from the reaction between feso4 and na2s2o3 at high pressure and high temperature in a stirred reactor. the solid product was purified by means of solvent extraction to remove sulfur. powder was characterized by x-ray diffraction (xrd), scanning electron microscopy (sem) and thermal analyses. results indicated that pyrite was prod...

this paper reports results of a study regarding the activities of nano structure mn/γ-al2o3 and γ-al2o3 catalysts for oxidation of 2-propanol (as a model of volatile organic compound). nanostructure of catalysts was revealed using xrd, sem and tem techniques. catalytic studies were carried out in u-shaped packed bed reactor under atmospheric pressure and at the reaction temperature of 150- 500°...

A novel generic method of silica supported catalyst system generation from a fluid state is presented. The technique is based on the combined flow and radiation (such as microwave, thermal or UV) induced co-assembly of the support and catalyst precursors forming nano-reactors, followed by catalyst precursor decomposition. The transformation from the precursor to supported catalyst oxide state c...

In the present study, selected metal ions (M = Cr, Mn, Co, Ni, Cu, Zn, and Ce) were introduced into iron oxide (spinel lattice) and screened for effectiveness for a high-temperature water–gas shift reaction. Simultaneous precipitation of Fe(III) nitrates along with metal nitrate(s) at optimal concentrations resulted in the formation of high-surface area nanosized catalysts. A noticeable interac...

nowadays, the use of innovative nano-technology in the food industry quality control has significantly increased and it is widely employed in numerous fields such as diagnosis of microbial toxin of foods using nano-biosensors, increasing food shelf-life with the help of nano-clay and nano-silver packaging, as well as changing some of the unpleasant organoleptic properties such as taste, color, ...

In this study, pyrite was produced by hydrothermal precipitation from the reaction between FeSO4 and Na2S2O3 at high pressure and high temperature in a stirred reactor. The solid product was purified by means of solvent extraction to remove sulfur. Powder was characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and thermal ...

the steps taken in designing a loop reactor for bulk propylene polymerization are discussed. the roles played by several parameters like particle growth factor, catalyst activity and solid fraction on reactor volume at different operating conditions are investigated. at first, based on a fixed production capacity and specific rate of catalyst, reactor volume is determined. next, the length and ...

h-zsm-5 nano-zeolites were synthesized by hydrothermal method using tetrapropylammonium hydroxide (tpaoh) as a template in the presence of various tpabr concentrations. the effect of different tpabr/tpaoh molar ratios was studied on the catalytic performance of dehydration of methanol to dimethyl ether (dme) in a fixed bed reactor under the same operating conditions (t=300°c, p=1 atm, and whsv=...