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991.
Swann William B. Jr.; Gómez ángel; Huici Carmen; Morales J. Francisco; Hixon J. Gregory 《Canadian Metallurgical Quarterly》2010,99(5):824
Identity fusion is a feeling of oneness with the group that induces people to tether their feelings of personal agency to the group. We accordingly proposed that increasing the agency of fused persons by elevating autonomic arousal would amplify their tendency to endorse and actually enact pro-ingroup behavior. In 4 experiments, increasing autonomic arousal through physical exercise elevated heart rates and fusion-unrelated activity among all participants. Fused participants, however, uniquely responded to arousal by translating elevated agency into endorsement of pro-group activity. These effects emerged both for endorsement of extreme behaviors for the group and for overt behaviors, specifically helping behavior (donating money to needy in-group members), and the speed with which participants raced a fusion-related avatar. The effects also generalized across 3 different arousal inductions (dodgeball, wind sprints, and Exercycle). Finally, fusion-related agency partially mediated the interactive effects of fusion and arousal on pro-group behavior. Apparently, autonomic arousal increases agency and identity fusion channels increased agency into pro-group behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
P. López-Arce L.S. Gomez-Villalba L. Pinho M.E. Fernández-Valle M. Álvarez de Buergo R. Fort 《Materials Characterization》2010,61(2):168-184
Slaked lime (Ca(OH)2) nanoparticles were exposed at 33% and 75% relative humidity (RH) to consolidate dolostone samples used in historical buildings. Non-destructive techniques (NDT) were applied to determine the chemical, morphological, physical and hydric properties of the stone samples, before and after 20 days treatment. Morphological and mineralogical characterisation of the nanoparticles was performed. 75% RH favors the consolidation process studied under Environmental Scanning Electron Microscopy (ESEM-EDS), spectrophotometry, capillarity, water absorption under vacuum, ultrasound velocity, Nuclear Magnetic Resonance (imaging and relaxometry) and Optical Surface Roughness analyses. At 75% RH the nanoparticles fill the pores and inter-crystalline dolomite grain contacts but do not favor calcite re-crystallization as it occurs at 33% RH. The ESEM, XRD and TEM analyses under 75% RH reveal the fast transformation of portlandite (Ca(OH)2) into vaterite (CaCO3), monohydrocalcite (CaCO3 · H2O) and calcite (CaCO3), and eventually the physical and hydric properties of the stones significantly improve. New insights are provided for the assessment of consolidation effectiveness of porous carbonate stones with calcium hydroxide nanoparticles under optimum RH conditions combining several NDT. 相似文献
993.
Perales E Martínez-Verdú FM Linhares JM Nascimento SM 《Journal of the Optical Society of America. A, Optics, image science, and vision》2010,27(10):2106-2114
We estimated the number of colors perceived by color normal and color-deficient observers when looking at the theoretic limits of object-color stimuli. These limits, the optimal color stimuli, were computed for a color normal observer and CIE standard illuminant D65, and the resultant colors were expressed in the CIELAB and DIN99d color spaces. The corresponding color volumes for abnormal color vision were computed using models simulating for normal trichromatic observers the appearance for dichromats and anomalous trichomats. The number of colors perceived in each case was then computed from the color volumes enclosed by the optimal colors also known as MacAdam limits. It was estimated that dichromats perceive less than 1% of the colors perceived by normal trichromats and that anomalous trichromats perceive 50%-60% for anomalies in the medium-wavelength-sensitive and 60%-70% for anomalies in the long-wavelength-sensitive cones. Complementary estimates obtained similarly for the spectral locus of monochromatic stimuli suggest less impairment for color-deficient observers, a fact that is explained by the two-dimensional nature of the locus. 相似文献
994.
F. López Gayarre M.I. Álvarez-Fernández C. González-Nicieza A.E. Álvarez-Vigil G. Herrera García 《Engineering Failure Analysis》2010,17(1):270-285
This work presents a forensic analysis of ground subsidence occurred in Lo Tacón industrial area, which is located at the outskirts of La Unión (Murcia, SE Spain). Subsidence was triggered by the collapse of abandoned underground mining labours occurred in 1998. Coinciding in time with this event, it was detected a seismic movement, whose epicentre was located close to the study area.In the first part the affected area is analysed and delimited, as well as the spatial and temporal evolution of the damages attributed to the collapse of 1998. Then the causes of ground failure are also determined, as well as their possible temporal and spatial relationship with the seismic movement detected. Through this analysis it is presented a methodology to determine the effects of this phenomenon. It consists on extending field work radially to all existing buildings within the affected area, considering the centre around the zone where the greatest damage was produced. Finally it is analysed the temporal and spatial evolution of the cracks inventoried in buildings to determine active areas where certain subsidence persists. According to the results presented in this work, it may be concluded that damages are the consequence of buildings constructed in a potentially dangerous area where ground settlement occurs due to mining subsidence. 相似文献
995.
The growing demand of hydrogen needs renewable sources of raw materials to produce it. Glycerol, by-product of biodiesel synthesis, could be a bio-renewable substrate to obtain hydrogen. A Ni(5.8%)-alumina catalyst was evaluated in the steam reforming of glycerol at 600–700 °C, atmospheric pressure, 16:1 water:glycerol molar ratio, and 3.4–10.0 h−1 WHSV. A glycerol aqueous solution was fed, while a nitrogen stream was co-fed. After 4 h-on-stream, conversion was 96.8% at 600 °C increasing to 99.4% at 700 °C, reaching the largest hydrogen selectivity (99.7%) at 650 °C. After 8 h, conversion decreases more significantly at 600 °C, while the hydrogen selectivity does not significantly change with temperature and increases by decreasing WHSV. After 4 h, the main by-product was methane (76–97%), increasing at higher temperature, followed by ethene, ethane, propene, and propane. At 700 °C and 10.0 h−1 WHSV, the main by-products were ethene (47%) and methane (37%); it could be associated to catalyst deactivation. 相似文献
996.
Verónica Palomares Izaskun Gil de Muro Miguel Bengoechea Teófilo Rojo 《Journal of power sources》2010,195(22):7661-7277
Two samples of commercial conducting carbon black and the carbon generated in situ during LiFePO4/C composite synthesis from citric acid are studied, with the aim of finding out whether carbon from the composite can fulfil the same function as carbon black in the electrode blend for a Li-ion battery. For this purpose, the carbon samples are analyzed by several techniques, such as X-ray diffraction, Raman spectroscopy, transmission electron microscopy, granulometry, BET specific area and conductivity measurements. Different cathode compositions and component proportions are tested for pellet and cast electrodes. Electrochemical results show that a moderate reduction of commercial carbon black content in both kinds of cathodes, by adding more LiFePO4/C composite, enhanced the electrochemical behaviour by around 10%. In situ generated carbon can partially replace commercial conducting carbon black because its high specific surface probably enhances electrolyte penetration into the cathode, but it is always necessary to maintain a minimum amount of carbon black that provides better conductivity in order to obtain a good electrochemical response. 相似文献
997.
Beatriz Zapata Miguel A. Valenzuela Jorge Palacios Enelio Torres-Garcia 《International Journal of Hydrogen Energy》2010
To increase the activity and stability of Ni/SiO2 catalysts, a series of Ni–Ca, Ni–K and Ni–Ce promoted catalysts were prepared by successive impregnations. The textural properties, reducibility and catalytic performance in the methane decomposition reaction were investigated. The catalyst containing 30 wt.% Ni and 30 wt.% cerium oxide greatly increased the conversion of methane (90% of equilibrium value) and improved the stability, whereas the Ni–K and Ni–Ca were less active and stable than the Ni/SiO2 catalyst. The results suggest that Ce addition prevents the sintering of nickel particles during reduction process maintaining a random distribution between the silica and cerium oxide improving the distribution and migration of deposited carbon. 相似文献
998.
Alfredo Iranzo Miguel Muñoz Eduardo López Javier Pino Felipe Rosa 《International Journal of Hydrogen Energy》2010
This work presents experimental performance results for a 50 cm2 Polymer Electrolyte Membrane (PEM) Fuel Cell, including polarization curves and Electrochemical Impedance Spectroscopy (EIS) analysis of the Fuel Cell. EIS results were used for the determination of the cell ohmic resistance as well as charge transfer resistances under different operating conditions. Different combinations of operating conditions and bipolar plate designs were analysed. In particular, the effect of the cathode oxygen concentration, reactant gases humidification, and bipolar plate (BP) design were assessed. Butler–Volmer (BV) kinetic parameters such as the charge transfer coefficient were also determined from Tafel plots. The electronic contact resistances were measured for both Bipolar Plate designs, and the membrane protonic resistances were calculated. Its dependence on the BP flow field design and operating conditions is addressed. The results obtained in this work are aimed both at gaining insight into the fundamental processes determining the fuel cell performance, and at determining parameters needed for Computational Fuel Cell Dynamics (CFCD) numerical simulations. 相似文献
999.
Luis Ortega-San-Martin José Ignacio Peña Ángel Larrea Vanesa Gil Victor M. Orera 《International Journal of Hydrogen Energy》2010
Cermets composed of submicron size alternating lamellae of CeO2, or 10% Gadolinia doped Ceria (GDC), and porous-metallic Cobalt have been prepared from eutectic oxide mixtures. A fine eutectic structure was obtained by fast directional solidification of the cobalt oxide–ceria oxide eutectic composite using the Laser Floating Zone (LFZ) technique. The resulting microstructure, with an interphase spacing down to 0.5 μm, was obtained for solidification rates of 750 mm/h. Textured cermets were obtained by subsequent reduction under H2 containing atmosphere of the eutectic oxide composite. The reduction kinetics was studied in the 550–750 °C temperature range and effective diffusion coefficients were obtained. The reduction process does not correspond to a typical thermally activated process. The cermets are composed of ceria lamellae of about 200 nm thickness alternated with porous-metallic cobalt lamellae of ≤400 nm. The lamellar microstructure of the cermets favours oxygen ion mobility through ceria and its size can be controlled by solidification rate of the eutectic precursor. These materials are proposed as SOFC anodes. 相似文献
1000.
This is the first comprehensive ultrastructural study on dwarf males with external gametangia in the ge in the genus Oedogonium, from androspore germination to the liberation of mature male gametes. The ultrastructure of the process in O. macrandrium Wittrok is similar to that of Bulbochaete hiloensis (Nordstedt) Tiffany, butwith two remarkable differences. In O. macrandrium : 1) instead of a true transverse wall, only condensed mucilage appears between the gametes of each antheridial cell, and 2) the cell wall between the basal cell and the basal most antheridial cell has simple plasmodesmata similar to those present in the transverse walls of vegetative cells, which are absent in B. hiloensis. 相似文献