H-2 Production by water radiolysis in presence of M/TiO2 (M= Pt; Au) nanocomposite films

International Conference in Energy and Sustainability in Small Developing Economies (ES2DE), PORTUGAL, JUL 10-12, 2017International audienceIn the present work we report on the synthesis of M/TiO2 (M=Pt, Au) nanocomposite films processed on Si-substrate. X-Ray diffraction and Raman experiments allowed the identification of formed phases. The hydrogen production has been carried out by gamma-irradiation of water in the presence of the nanocomposite films. The existence of Au- and Pt-TiO2 thin films resulted in a significant enhancement of H-2 production which is promising for clean energy applications

H-2 Production by water radiolysis in presence of M/TiO2 (M= Pt; Au) nanocomposite films

International Conference in Energy and Sustainability in Small Developing Economies (ES2DE), PORTUGAL, JUL 10-12, 2017International audienceIn the present work we report on the synthesis of M/TiO2 (M=Pt, Au) nanocomposite films processed on Si-substrate. X-Ray diffraction and Raman experiments allowed the identification of formed phases. The hydrogen production has been carried out by gamma-irradiation of water in the presence of the nanocomposite films. The existence of Au- and Pt-TiO2 thin films resulted in a significant enhancement of H-2 production which is promising for clean energy applications

Application of the Wavelet Multi-resolution Analysis and Hilbert transform for the prediction of gear tooth defects

In machine defect detection, namely those of gears, the major problem is isolating the defect signature from the measured signal, especially where there is significant background noise or multiple machine components. This article presents a method of gear defect detection based on the combination of Wavelet Multi-resolution Analysis and the Hilbert transform. The pairing of these techniques allows simultaneous filtering and denoising, along with the possibility of detecting transitory phenomena, as well as a demodulation. This paper presents a numerical simulation of the requisite mathematical model followed by its experimental application of acceleration signals measured on defective gears on a laboratory test rig. Signals were collected under various gear operating conditions, including defect size, rotational speed, and frequency bandwidth. The proposed method compares favourably to commonly used analysis tools, with the advantage of enabling defect frequency isolation, thereby allowing detection of even small or combined defects.Deposited by bulk importTS 11.02.1

Effect of CdSe nanoparticles incorporation on the performance of P3OT organic photovoltaic cells

International audiencePhotoluminescence and photovoltaic properties of P3OT:%CdSe nanocomposite films are investigated as a function of the mass concentration (wt%) of the CdSe nanoparticles (NPs) incorporated in the films. The incorporation of CdSe NPs produces a quenching of the photoluminescence and improves the performance of the nanocomposite solar cells. These effects are explained in terms of exciton dissociation and charge separation occurring at P3OT/CdSe interfaces within the Forster formalism, involving non-radiative energy transfer from the donor (P3OT) to the acceptor (CdSe NPs). An exciton quenching rate constant of 1.4 x 10(-10) cm(3) s(-1) is determined using the Stern-Volmer equation. In addition, scanning electron microscopy (SEM) images reveal that surface morphology is changed by CdSe NPs incorporation, in agreement with FTIR spectra. The current density-voltage (I-V) characteristics of ITO/P3OT:%CdSe/Al photovoltaic cells performed for different CdSe concentrations are also reported and indicate a significant improvement of the photovoltaic parameters cells, particularly, the conversion efficiency becomes 20 times greater than that of the cell based on pure polymer. (C) 2015 Elsevier Ltd. All rights reserved