this paper investigates hollow and porous alumina nanospheres that were previously synthesized to be used for the dehydration of methanol to dimethyl ether (dme). as hollow nanostructures possess characteristics such as low density and high surface to volume ratio, their catalytic activity between hollow and porous structure is compared. for this purpose, three most important parameters (acidit...

The interactions of ethylene glycol with a partially reduced rutile TiO2(110) surface have been studied using temperature programmed desorption (TPD). The saturation coverage on surface Ti rows is determined to be 0.43 monolayer (ML), slightly less than one ethylene glycol per two Ti sites. Most of the adsorbed ethylene glycol (∼80%) undergoes further reactions to yield other products. Two majo...

A new experimental determination of the stability relationships for the dehydration of gypsum to the hemihydrate mineral bassanite at elevated temperature and pressure is described. The experimental method used depends on the observation of very small changes in pressure on the onset of reaction due to the potential volume change in the reaction. The technique yields P T data of very high preci...

In this investigation, a parametric study was performed using the transient cold-start model presented in our previous paper, in which the ice melting process and additional constitutive relations were newly included for transient cold-start simulations of polymer electrolyte fuel cells (PEFCs) from a sub-zero temperature (-20°C) to a normal operating temperature (80°C). The focus is placed on ...

This study aimed to evaluate the effects of temperature, time, and thickness of tomatoes fruits during adiabatic drying process. Dehydration, a simple and inexpensive process compared to other conservation methods, is widely used in the food industry in order to ensure a long shelf life for the product due to the low water activity. This study aimed to obtain the best processing conditions to a...

The physical and chemical properties of tungsten oxide supported on SBA-15 mesoporous silica prepared by a controlled grafting process through atomic layer deposition (ALD) were studied using complementary characterization methods. X-ray diffraction, optical absorption, and transmission electron microscopy showed that tungsten oxide species are highly dispersed on SBA-15 surfaces, even at 30 wt...

The thermal calcination of borax pentahydrate was investigated for both dehydration and decomposition steps at temperatures between 392 and 573 K in a controlled fluidized bed drier. The best kinetic parameters (reaction rate constants, reaction order and equilibrium values) of both steps were determined by the genetic algorithm (GA) method for each calcination temperature in respect of relativ...