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991.
Huguet Pascal; Charbonnier Emmanuelle; Monteil Jean-Marc 《Canadian Metallurgical Quarterly》1999,3(2):118
The authors predicted that individuals who see themselves as average (e.g., who have a generalized belief in being no better or worse than others) do not engage in social loafing, unlike those who see themselves as generally superior to others. As expected, study participants who felt uniquely superior expended less effort when working collectively than when working coactively on an easy task, but they actually worked harder collectively than coactively on a more challenging task. Such effects did not occur in participants who perceived themselves as average. Taken together, these findings provide further support for S. J. Karau and K. D. Williams's (see record 1994-33384-001) collective effort model. They also suggest that what people come to believe about the relation between the self and others is a crucial factor in collective work contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Sandrine Pessaud Franois Gervais Corinne Champeaux Pascal Marchet Alain Catherinot Marina Licheron Jean Louis Longuet Frdric Ravel 《Materials Science and Engineering: B》1999,60(3):205-211
Laser ablation by varying the number of consecutive laser pulses upon two targets, one superconducting YBa2Cu3O7, the other insulating MCuO2 (M=Sr, Ca), is used to build thin films of tuneable average compositions. Most of the samples are found to display high-Tc superconductivity with critical temperature generally higher than the 60 K of the ‘Cava phase’, the prototypic structure with two consecutive conducting CuO2 planes and containing same types of atoms. The properties of the samples are not linearly dependent on the concentration of species coming from the insulating target. In addition, they depend not only on the ratio of the number of pulses on each target, but also on the number of consecutive pulses on each target. Thin films are characterized by temperature-dependent DC conductivity, X-ray diffraction, Castaing microprobe and infrared reflectivity spectroscopy. Present results suggest the robustness of high-Tc superconductivity, possibly related to a ‘Cava-phase-like’ skeleton. 相似文献
993.
Homogeneous dispersion of microemulsion containing palladium nanoparticles in scCO2 is, for the first time, observed via sapphire window reactor and these particles show an unusual reluctance for double bond hydrogenation of citral aldehyde at hydrophobic end rather than hydrophilic end (high regioselectivity) owing to the unique micelle environment in supercritical carbon dioxide that guide a head-on attack of the molecule. 相似文献
994.
Jean-Franois Coutouly Pascal Deprez Florin Breaban Jean-Paul Longuemard 《Journal of Materials Processing Technology》2009,209(17):5730-5735
The ablation of coatings (paint, varnish, oxides, etc.) using a pulsed laser beam is a process that has a number of major benefits compared with conventional cleaning techniques (mechanical and chemical), the main advantage being the possibility of removing the surface layer without any risk of damaging the substrate. Another benefit, and certainly not the least, is the non-use of toxic solvents or chemical products that are difficult to eliminate and, in any case, will be banned from use in the near future. However, it must be stressed that, notwithstanding the above benefits, laser ablation of painted surfaces can only give good quality results if the process is properly controlled. The procedure discussed in this paper has two aims: the first involves establishing a thermal model of the interaction, applied to the ablation of paint from metal surfaces by infra-red laser. The second involves proposing an optimised paint removal process validated by experimental measurements. This second objective will be based on an analysis method of the acoustic signal transmitted by the ablation plasma beam. 相似文献
995.
To develop high performance steels for automotive applications, enhanced strengthening mechanisms are required. This study aims at assessing the critical parameters leading to the refinement of the strain‐induced ferrite matrix of thermomechanically processed multiphase steels. Hot rolling simulations allowed the definition of the temperature, strain and cooling rate conditions bringing about the formation of strain‐induced ferrite with a reduced grain size. The relationship between the deformation and the concurrent or subsequent phase transformations is highlighted thanks to a thorough characterisation of the generated microstructures. It is also shown that the prior austenite grain size influences the distribution of the second phases within the finely grained ferrite matrix. 相似文献
996.
997.
Tim Van Rompaey Frederic Lani Bart Blanpain Patrick Wollants Pascal J. Jacques Thomas Pardoen 《Metallurgical and Materials Transactions A》2006,37(1):99-107
A three-dimensional finite-element microstructural cell model involving an inclusion of retained austenite embedded within
a ferrite grain, which is surrounded by a homogeneous matrix representing the behavior of a transformation-induced-plasticity
(TRIP)-assisted multiphase steel, was developed in order to address the micromechanics of the martensitic transformation in
small isolated austenite grains. The transformation of a single martensite plate is simulated after various amounts of prior
plastic deformation under different in-plane loading conditions. The values of the mechanical driving force and of the elastic
and plastic accommodation energies associated with the transformation are calculated as a function of the externally applied
loading conditions. The mechanical driving force and the total accommodation energy are of the same order of magnitude. The
mechanical driving force depends upon the stress state and is the highest for plane-strain conditions. The total accommodation
energy is almost independent of the stress state. It is affected by the amount of plastic straining prior to transformation
and is very much dependent on the level of the shear component of the transformation strain. The results of this study provide
guidelines for the development of realistic stress-state-dependent transformation evolution laws for TRIP-assisted multiphase
steels. 相似文献
998.
Daniel Beysens Marc Muselli Iryna Milimouk Catherine Ohayon Simon M. Berkowicz Emmanuel Soyeux Marina Mileta Pascal Ortega 《Energy》2006
Dew water was collected from several passive foil-based radiative condensers established in a variety of geographic settings: continental (Grenoble, in an alpine valley, and Brive-la-Gaillarde, in the Central Massif volcanic area, both in France), French Atlantic coast (Bordeaux), eastern Mediterranean (Jerusalem, Israel), and the island of Corsica (Ajaccio, France) in the Mediterranean Sea. In Ajaccio two large 30 m2 condensers have been operating since 2000. Additional semi-quantitative dew measurements were also carried out for Komi?a, island of Vis (Croatia) in the Adriatic Sea, and in Mediterranean Zadar and Dubrovnik (both in Croatia). Dew potential was calculated for the Pacific Ocean island of Tahiti (French Polynesia). The data show that significant amounts of dew water can be collected. Selected chemical and biological analyses established that dew is, in general, potable. Continued research is required for new and inexpensive materials that can enhance dew condensation. 相似文献
999.
Pascal Elleaume Anmick Ropert 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2003,500(1-3):18-24
Rings of 6–8 GeV with circumstance of about 2 km or more could provide X-ray brightness that significantly exceeds that of any present facility, opening new research opportunities. 相似文献
1000.
This paper presents a performance analysis of optical burst switching (OBS) networks with ring and chordal ring topologies. The performance analysis considers signaling protocols with one-way reservation schemes, being focused on the following protocols: just-in-time (JIT), Jumpstart, JIT+, just-enough-time (JET) and Horizon. It is shown that for a network with 20 nodes, the nodal degree gain due to the increase of nodal degree from two (ring) to three (chordal ring) is about three orders of magnitude in the first hop of both topologies, and is between two and three orders of magnitude in the last hop of each topology. It is also shown that the largest chord length gain, in a 20-node OBS network with a chordal ring topology, is slightly less than two orders of magnitude. 相似文献