The integration of the steam reforming and combustion of methane in a catalytic microchannel reactor has been simulated by computational fluid dynamics (CFD). Two models including 4 or 20 square microchannels of 20 mm of length and 0.7 mm of side have been developed. It has been assumed that a thin and homogeneous layer of…
Novel controlled release formulations (CRFs) were developed for reducing leaching of herbicides and contamination of groundwater. The herbicide metribuzin (MTB) was entrapped within a sepiolite-gel matrix using a novel and ultrasound-based technique. Different sepiolite/herbicide matrices (either as a gel or as a powder after freeze-drying) were prepared with pesticide loading between 28.6 and 9.1%. The…
A mimetic polymer of plant cutin have been synthesized from 9,10,16-trihydroxyhexadecanoic (aleuritic) acid through a low temperature polycondensation reaction. Reaction conditions (solvent, catalyst, temperature, etc…) were studied and modified to optimize yield and product characteristics. The resulting polyaleurate polymer was characterized by Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC), X-ray Diffraction…
Nanocomposite coatings combining hard phases (TiB2, TiC) with an amorphous carbon (a-C) were developed to provide a good compromise between mechanical and tribological properties for M2 steels used in a wide variety of applications such as cutting tools, bearings and gear mechanisms. A combined d.c.-pulsed and r.f.-magnetron deposition process was used to deposit nanocomposite TiBC/a-C…
Dielectric Barrier Discharges (DBD) operated at atmospheric pressure and working at reduced temperatures (T < 115 °C) and a copper–manganese oxide catalyst are combined for the direct decomposition and the steam reforming of methanol (SRM) for hydrogen production and for the preferential oxidation of CO (CO-PROX)
Kalsilite (the low-temperature form of KAlSiO4) is used as the precursor of leucite, an important component in porcelain-fused-to-metal and ceramic-restoration systems, and it has also been proposed as a high-thermal expansion ceramic for bonding to metals. The present study reports the hydrothermal synthesis and characterization of pure kalsilite from kaolinite in subcritical conditions, as well…
The process of investigating paintings includes the identification of materials to solve technical and historical art questions, to aid in the deduction of the original appearance, and in the establishment of the chemical and physical conditions for adequate restoration and conservation. In particular, we have focused on the identification of several samples taken from six…
An easy solvothermal route has been developed to synthesize the first mesoporous Er2O3-TiO2 mixed oxide spherical particles composed of crystalline nanoplatelets, with high surface area and narrow pore size distribution. This synthetic strategy allows the preparation of materials at low temperature with interesting textural properties without the use of surfactants, as well as the control…
Combined kinetic analysis has been applied for the first time to the thermal degradation of polymeric materials. The combined kinetic analysis allows the determination of the kinetic parameters from the simultaneous analysis of a set of experimental curves recorded under any thermal schedule. The method does not make any assumptions about the kinetic model or…
This work presents the synthesis of a nanostructured titania support and its subsequent utilization for the gold particles deposition and application in the reaction of the CO oxidation. A functionalized ionic liquid has been used as a templating agent for the titanium oxide synthesis resulting in a high specific surface nanostructured titania anatase. The as…