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[en] Photovoltaic (PV) systems are almost entirely benign in operation, and potential environmental hazards occur at the production and disposal stages. There are well established methods of monitoring and controlling potential hazards caused by the semiconductor materials used in PV modules such as silicon, copper indium diselenide and cadmium telluride. The main environmental hazards of photovoltaics are connected to the production processes. These processes require an input of energy, and this energy is derived from the standard fuel mix of the nation in which production takes place. The production of PV systems therefore has associated with it, emissions of greenhouse and acidic gases. However, as the new thin film PV technologies come into production, and the scale of production increases, the energy input to PV systems will decrease considerably, with consequent reduction in carbon dioxide emissions, to levels below that of other electricity generating technologies. (Author)
[en] In this paper, the recent research progress on triphenylamine (TPA)-based donor-acceptor (D-A) amorphous polymers including our developed polymers is reviewed. TPA has three-dimensional branched structures and can provide D-A polymers containing D and A units in the main chain or side chain. The use of TPA-based amorphous polymers in the fabrication of organic photovoltaics (OPVs) offers great advantages over the use of a polycrystalline film in terms of high reproducibility of the OPV performance. The amorphous polymer design using TPA, therefore, indicates a promising direction for the development of new donor materials in OPVs
[en] With the advancement of synthesis methods, boron nitride nanotubes seem to become increasingly valuable in fundamental physical research and find applications in a number of forms, from dyed neutron-absorbing fabrics to high-temperature catalysts and photovoltaic devices.
[en] Tracking for particle physics instrumentation in SOI technology (TRAPPISTe-1) is an R and D project to study the feasibility of manufacturing a monolithic active pixel sensor (MAPS) in silicon on insulator (SOI) technology. The first prototype of this series of sensors has been designed with a 2 μm SOI CMOS technology available in UCL, Louvain-la-Neuve. Simulations are presented for this prototype. Leakage measurements have been done on a photovoltaic cell, manufactured in the same process on a low-resistivity substrate. As a next step, a high-resistivity demonstrator will be designed.
[en] Routes for the synthesis of a series of rotaxanes and catenanes incorporating porphyrin, ferrocene and fullerene moieties by the Sauvage metal template technique are described. Photophysical studies on these materials show that excitation of the porphyrin component causes a series of events along an energy gradient leading to long-lived long distance charge-separated radical pair states with lifetimes as long as 32 μs in tetrahydrofuran solution at ambient temperatures. (authors)
[en] The drop in the prices of photovoltaic systems appeared in 2011, this fall was due to the collapse of the price of the module that reached 45% in one year. Other components' prices have also decreased but not to such an extent. The reason is that the production capacities have increased very fast in 2010 when the offer was still below the demand. Now, in 2012 the sale of photovoltaic systems have slowed down because of the crisis and the partial end of financial support programs from European states. The market is now very competitive with low prices, but a lot of enterprises are expected to reorganize or even to bankrupt. For the rest of 2012 the trend is unknown but for a longer term new technological progress are looming: the replacement of silver by copper, the fabrication of thinner sheets of glass and the use of less expensive polymers. These technological advances will give a new and sane margin for the reduction of costs and will make photovoltaic energy more competitive with other energies. (A.C.)
[en] The tilt angle influences the amount of energy collected by a photovoltaic module. However, representations of these effects on the energy yield and the performance of the PV system are commonly based on the theoretical calculations, whereas there is a lack of experimental investigations. To verify the calculations, an experimental setup has been installed at the Department of Electrical and Computer Engineering, University of Tehran. Some results of this test station, from March, 1999 to January, 2000 are represented in this paper. (Author)