University of Patras

About: University of Patras is a education organization based out in Pátrai, Greece. It is known for research contribution in the topics: Population & Catalysis. The organization has 13372 authors who have published 31263 publications receiving 677159 citations. The organization is also known as: Panepistímio Patrón.

Production of electricity by photoelectrochemical oxidation of ethanol in a PhotoFuelCell

Abstract: Photocatalytic oxidation of ethanol was carried out in a non-biased photoelectrochemical cell at high pH. The cell was made of two compartments separated by a silica frit, both filled with aerated NaOH electrolyte. The anode electrode bore multilayer nanocrystalline titania, made of either commercial Degussa P25, sol–gel synthesized titania or both. The cathode electrode was made of carbon cloth carrying Carbon Black and Pt as catalyst. When the anode was excited by UVA radiation (363 nm), the cell produced electricity very efficiently. The open-circuit voltage was 0.88 V in the absence and almost 1.2 V in the presence of ethanol. The current increased by more than an order of magnitude by adding ethanol, showing that it is much more efficient to oxidize ethanol than to oxidize (split) water. The performance of the cell improved when a compact titania layer was introduced between the FTO electrode and the thick photocatalytic layer. Ethanol was used as a model fuel but the cell can run on many other organic substances as well. The cell can be used as a source of renewable electricity, by consuming organic wastes under photo-excitation, thus making a PhotoFuelCell.

Intensely Luminescent Materials Obtained by Combining Lanthanide Ions, 2,2‘-Bipyridine, and Poly(ethylene glycol) in Various Fluid or Solid Environments

Abstract: Steady-state luminescence spectroscopy and luminescence decay analysis have been employed to study the association of two rare earth ions (i.e., Eu3+ and Tb3+) with poly(ethylene glycol) in the absence and in the presence of 2,2‘-bipyridine, which acted as an antenna of near-UV radiation. Three different systems have been studied at various polymer concentrations, i.e., aqueous solutions, transparent composite organic/inorganic sol−gel matrixes made by hydrolysis of tetramethoxysilane, and polymer matrixes. The photophysical behavior of the luminescent species has been studied in conjunction with the poly(ethylene glycol) content. In both aqueous solutions and silica matrixes, luminescence intensity and decay time were found to increase by increasing polymer concentration. Addition of 2,2‘-bipyridine resulted in complex formation between the ligand and the lanthanide ions. This complex was stabilized by association with the polymer chains. Excitation at the ligand absorption wavelength (337 nm) resulted i...

Deposition and optical properties of optimised ZnS/Ag/ZnS thin films for energy saving applications

Abstract: Copyright (c) 1997 Elsevier Science S.A. All rights reserved. Dielectric/Metal/Dielectric (D/M/D) thin films deposited on glass offer the possibility of significant energy savings in buildings and can find other applications as components of advanced materials design. In an effort to reduce the complexity and cost of production of D/M/D films, physical vapour deposition was used for the laboratory manufacture of ZnS/Ag/ZnS films on glass. ZnS was used because of its high refractive index, ease of deposition and low cost; Ag was used because of its low absorption in the visible spectrum. The films produced were of good quality, with luminous transmittance as high as 83.9%, IR reflectance above 90% and total hemispherical emittance equal to 6%. The ZnS layers were found not only to antireflect the Ag layer, but also to stabilise the ZnS/Ag/ZnS film, improve its adherence on glass and increase the film thermal resistance up to 240°C. A multipurpose computational optics tool based on the characteristic matrix formulation has been developed for the design and optimisation of the D/M/D films: The optimum thickness of each dielectric layer required to maximise the film luminous transmittance for a given metal layer thickness was established. The optical properties of the films designed were also predicted and the most suitable materials were identified. The optical properties of the films produced were measured and were found to compare favourably with the theoretical predictions. © 1997 Elsevier Science S.A.

The whole genome sequence of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), reveals insights into the biology and adaptive evolution of a highly invasive pest species

Abstract: The Mediterranean fruit fly (medfly), Ceratitis capitata, is a major destructive insect pest due to its broad host range, which includes hundreds of fruits and vegetables. It exhibits a unique ability to invade and adapt to ecological niches throughout tropical and subtropical regions of the world, though medfly infestations have been prevented and controlled by the sterile insect technique (SIT) as part of integrated pest management programs (IPMs). The genetic analysis and manipulation of medfly has been subject to intensive study in an effort to improve SIT efficacy and other aspects of IPM control. The 479 Mb medfly genome is sequenced from adult flies from lines inbred for 20 generations. A high-quality assembly is achieved having a contig N50 of 45.7 kb and scaffold N50 of 4.06 Mb. In-depth curation of more than 1800 messenger RNAs shows specific gene expansions that can be related to invasiveness and host adaptation, including gene families for chemoreception, toxin and insecticide metabolism, cuticle proteins, opsins, and aquaporins. We identify genes relevant to IPM control, including those required to improve SIT. The medfly genome sequence provides critical insights into the biology of one of the most serious and widespread agricultural pests. This knowledge should significantly advance the means of controlling the size and invasive potential of medfly populations. Its close relationship to Drosophila, and other insect species important to agriculture and human health, will further comparative functional and structural studies of insect genomes that should broaden our understanding of gene family evolution.