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[en] This branch driver allows in association with the FIFO memories of the microcomputer Micral, very fast exchanges with the 7 crates of a CAMAC branch. A CAMAC programm (command, test, read, write) is loaded in the 1K FIFO buffer of the Micral before execution time and executed in sequence at a rate of 1,5μs per CAMAC command. After programm execution, data may be transferred directly on a magnetic tape
[fr]Ce controleur de branche permet, en association avec les memoires piles du calculateur MICRAL, un echange tres rapide avec le chassis (7 maximum) d'une branche CAMAC. Un programme (ordre, test, lecture, ecriture) est charge dans les piles et execute sur une demande de MICRAL ou sur une demande exterieure. Apres l'execution du programme (acquisition), le contenu des piles peut etre decharge sur une bande magnetique. L'ensemble est destine a une acquisition rapide de donnees avec interpretation differee sur le miniordinateur MICRAL ou sur un calculateur plus puissant. Pendant la preparation d'experiences de physique utilisant une branche CAMAC connectee sur un calculateur plus puissant, l'ensemble permet la mise au point de l'experience en remplacant le calculateur
[en] This work describes a fast electrodeposition method for generating gold plasmonic electrodes and their use as active plasmonic devices. Gold nanoparticles (AuNPs) are easily obtained on large areas (up to several square centimeters) on indium tin oxide (ITO) electrodes using electroreduction of an Au"I"I"I salt by chronoamperometry. These AuNP substrates exhibit a strong localized surface plasmon resonance (LSPR) signal in the visible range, and constitute low-cost plasmonic electrodes. The average size, the density and the dispersity of the AuNPs, as seen by scanning electron microscopy (SEM), can be modulated by the potential applied during electroreduction. In this way, the LSPR can be varied from 680 nm to 580 nm with a concomitant marked evolution of the full-width at half-maximum from 200 to 80 nm. An important result is that the LSPR of substrates generated at −0.9 V using a charge density of 20 mC cm"−"2 is close to that of AuNP gratings obtained using e-beam lithography. In a second step, the best AuNP-modified electrodes were covered with an ultrathin organic film of bisthienylbenzene (BTB) generated by electroreduction of the corresponding diazonium salt. This film switches between a conducting and an insulating state depending on the applied voltage. The effect of the switch on the plasmonic properties of AuNPs is reported. Despite the small thickness of the film (below 15 nm), its conductance switch leads to a reversible modulation of the LSPR intensity by as much as 25%.
[en] This publication aims at proposing a detailed analysis of costs of four surface geothermal technologies: vertical geothermal probes, geothermal energy on aquifer, horizontal sensors, and geothermal baskets. It first presents the adopted methodology, some general hypotheses (studied examples, heat pumps, comparative solutions for heating, energy costs, hypotheses for cooling, aids and loans), and the four technologies with their specific hypotheses. Results are presented for the different building sectors: individual housing, collective housing, and office building
[en] This paper describes the attachment of conjugated oligomers onto electrode surface through the reduction of diazonium compounds. In this connection some properties of conjugated oligomers and of layers grafted through diazonium electroreduction will first be briefly presented. The electrochemical behavior of conjugated oligomers grafted on a surface using diazonium electroreduction will then be discussed. (paper)
[en] This work describes two different methods for obtaining electrodes covered with gold nanoparticles: electron-beam lithography and electroreduction of an Au (iii) salt by chronoamperometry. Localized surface plasmon resonances of these different electrodes have been compared. In a second step, these plasmonic AuNP electrodes were covered with an ultrathin organic film of bisthienylbenzene which displays a reversible voltage-dependent switch between conducting and insulating states. The effect of this conductance switch on the plasmonic properties of the AuNPs has been studied. (paper)
[en] A mixture of Co(phen)"3"+"/"2"+ and Co(EtPy)"3"+"/"2"+ complexes, where EtPy is a terpyridine ligand bearing an 3,4- ethylenedioxythiophene (EDOT) substituent, has been used as redox mediator in dye-sensitized solar cells. This combination of cobalt complexes allows an electron cascade leading to enhanced cell efficiency. To explain this result, we propose a synergy between the EDOT-functionalized cobalt complex and the PEDOT counter-electrode, which favors electron transfer and reduces recombination.
[en] Highlights: ► Electrochemistry and SECM to generate copper nanowires with quantized conductance. ► Stable atomic contacts lasting for several hundreds of seconds have been obtained. ► The quantized conductances are independent of the tip and gap size. ► The method allows contacts to be generated in the presence of chosen molecules. ► Four-electrode configuration opens the route to redox gated atomic contact. - Abstract: Scanning electrochemical microscopy, SECM, is proposed as a tool for the fabrication of copper nanowires. In a first step, configuration based on two electrodes, a platinum UME (cathode) and a copper substrate (anode), operating in the SECM configuration was employed. For nanowires generated in water the conductance changes stepwise and varies by integer values of the conductance quantum G0. The formation of atomic contacts is supported by the ohmic behavior of the I–V curve. It depends neither on the UME tip radius nor on the initial gap size between tip and substrate. Atomic contacts generated in aqueous solutions of sodium dodecyl sulfate (SDS) below the critical micellar concentration (CMC) have conductances below 1G0 attributed to molecular adsorption on the contact. In some cases, the nanowires have low conductance, 0.01G0. The corresponding I–V curve shows tunneling rather than ohmic behavior, suggesting that molecular junctions are formed with a few surfactant molecules trapped between the two electrodes. Finally, copper nanowires with quantized conductance have been generated using the SECM operating in a four-electrode setup. Thanks to the reference electrode, this configuration leads to better control of the potential of each working electrode; this setup will make it possible to evaluate the conductance variation and/or modulation upon electrochemical stimuli.
[en] This guide presents the vision of the professionals of the AFPG (the French professional association of geothermal energy) for a good design of moderate-temperature (inferior to 30 C) water loop based on geothermal energy or BETEG in order to meet thermal needs (heat and cold) at the scale of several buildings while sharing geothermal capture systems. The authors first present the BETEG, its associated geothermal resources, its different production modes, its ability to share energy among buildings, its ability for evolution and modularity, its potential in the valorisation of thermal storage, its control. It describes the various equipment and their components: capture device, sharing device, production device, control device. Its describes the principle of a moderate-temperature water loop (communication, supply, storage, valorisation, decentralisation of production), briefly presents some characteristics of an application depending on its scale, and evokes the assessment and definition of energetic needs. Then, other aspects of an operation are addressed: legal framework of an energy network, operation planning, intervener and funding, and regulatory framework of surface geothermal energy. Some cases are finally presented as returns on experience
[en] This book first describes the role of energy in the development of nano-sciences, discusses energy needs, the perception of nano-sciences by societies as far as the energy challenge is concerned, describes the contribution of nano-catalyzers to energy and how these catalyzers are prepared. A second part addresses the new perspectives regarding carbon: production of biofuels from biomass, process involved in CO2 geological storage, improvement of solar fuel production with the use of nano-powders. The third part describes the new orientations of solar energy: contribution of the thin-layer inorganic sector to photovoltaic conversion, perspectives for organic photovoltaic cells, operation of new dye-sensitized nanocrystalline solar cells. The fourth part addresses the hydrogen sector: credibility, contribution of biomass in hydrogen production, production of hydrogen by electrochemistry, new catalyzers for electrolyzers and fuel cells. The last part address improved electrochemical reactors