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81.
Osana Helena P.; Lacroix Guy L.; Tucker Bradley J.; Idan Einat; Jabbour Guillaume W. 《Canadian Metallurgical Quarterly》2007,99(4):888
This study extended the work of S. Siddiqui, R. F. West, and K. E. Stanovich (1998), who studied the link between general print exposure and syllogistic reasoning. It was hypothesized that exposure to certain text structures that contain well-delineated logical forms, such as popularized scientific texts, would be a better predictor of deductive reasoning skill than general print exposure, which is not sensitive to the quality of an individual's reading activity. Furthermore, it was predicted that the ability to generate explanatory bridging inferences while reading would also be predictive of syllogistic reasoning. Undergraduate students (N = 112) were tested for vocabulary, nonverbal cognitive ability, exposure to general print, exposure to popularized scientific literature, and the ability to comprehend texts distinguished by the number of inferences that must be generated to support comprehension. Hierarchical multiple regression analyses showed that a combined measure of exposure to general and scientific literature was a significant predictor of syllogistic reasoning ability. Additionally, the ability to comprehend high-inference-load texts was related to solving syllogisms that were inconsistent with world knowledge, indicating an overlap in deductive reasoning skill and text comprehension processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Ziad Damaj Aude Naveau Laurent Dupont Eric Hénon Guillaume Rogez Emmanuel Guillon 《Inorganic chemistry communications》2009,12(1):17-20
A solid CoII complex with l-proline as ligand was synthesized and fully characterized using spectroscopic studies, magnetic data, and DFT calculations. Dioxygen scavenging properties were investigated by UV/Vis spectroscopy and oxymetry techniques. The Co-proline system presented very interesting properties in matter of oxygen absorption capacity both in solution and incorporated in a polymer matrix. 相似文献
83.
Temporal Regionalization of 7-Day Low Flows in the St. Lawrence Watershed in Quebec (Canada) 总被引:1,自引:1,他引:0
Ali Arkamose Assani Alain Chalifour Guillaume Légaré Caza-Szoka Manouane Denis Leroux 《Water Resources Management》2011,25(14):3559-3574
Winter and summer 7-day low flows of eighteen natural rivers in the St. Lawrence River watershed of Quebec were analyzed over
the period from 1934 to 2000. The rivers were first subdivided into three modes using principal component analysis. Two of
these modes are located on the south shore of the St. Lawrence River, respectively south (Southeast mode) and north (East
mode) of the 47°N, and the third (Southwest mode) is located on the north shore. The Southeast mode shows a significant increase
in 7-day low flows in winter and summer due to increasing summer and fall precipitation, whereas the Southwest mode shows
a significant decrease in summer 7-day low flows due to an increase in evapotranspiration. No significant change in winter
and summer 7-day low flows is observed in the East mode. Results show that the variability of 7-day low flows and their link
with climate indices are mainly seasonally dependent. The North Atlantic Oscillation (NAO) is the only index which is correlated
to 7-day low flows in all three modes. This correlation is positive for north shore rivers and negative for south shore rivers.
Furthermore, only north shore rivers are correlated to NAO in both winter and summer. 相似文献
84.
Schoukens J. Vandersteen G. Pintelon R. Guillaume P. 《Automatic Control, IEEE Transactions on》1999,44(2):343-347
Presents a generalized frequency domain identification method to identify single-input/single-output (SISO) systems combining two previously published extensions in one method: arbitrary but persistent excitations are allowed and a nonparametric noise model is extracted from the same data that are used to identify the system. The method is directly applicable to identification in feedback if an external persistently exciting reference signal is available 相似文献
85.
Guillaume Mouret Dominique Thomas Sandrine Chazelet Jean-Christophe Appert-Collin Denis Bemer 《Journal of aerosol science》2009,40(9):762-775
This paper presents experimental data for penetration of nanoparticles in the 4–30 nm size range through fibreglass filters perforated with defined pinholes at 5 and 15 cm/s. Results show that, when the filter is damaged, penetration increases with decreasing particle diameter. This lower performance is more significant for filters with high airflow resistance. A model explaining the experimental data has been designed based on balanced, laminar airflow inside the pinhole; these conditions were confirmed by detailed study. The experimental points agreed very closely with this model. 相似文献
86.
Guillermo Quijano Annabelle Couvert Abdeltif Amrane Guillaume Darracq Catherine Couriol Pierre Le Cloirec Ludovic Paquin Daniel Carrié 《Chemical engineering science》2011,66(12):2707
This work aims to evaluate the feasibility of using imidazolium ionic liquids (ILs) in the design of multiphase bioreactors for the removal of volatile organic compounds (VOCs). The IL affinity for three model VOCs (dimethyl sulfide, dimethyl disulfide and toluene) was evaluated by means of the dimensionless partition coefficient (K). It was observed that ILs showed K values comparable to typical liquid solvents used in multiphase bioreactors for VOC biodegradation (K values ranged from 0.009 to 0.011, 0.0012 to 0.0013 and 0.00061 to 0.00096 for dimethyl sulfide, dimethyl disulfide and toluene, respectively). Toxicity tests showed that both ILs at concentrations of 5% and 10% (v/v) inhibited the glucose uptake of an activated sludge during approximately 24 h. After such lag period, the microorganisms were able to recover its metabolic activity. However, VOC biodegradation experiments showed that ILs at 5% (v/v) were toxic for the activated sludge and a toxic synergistic effect of the IL–VOC combination likely occurred. After acclimation to the target VOCs, only the toluene biodegradation capacity was significantly increased in the presence of ILs. These toxic effects represent a key drawback for the potential of IL-based multiphase systems devoted to VOC biodegradation. Therefore, this study suggests that microbial acclimation only to the VOCs is not enough to get an efficient biodegradation in multiphase systems including ILs as non-aqueous phases. 相似文献
87.
Bernard Charra Guillaume Jean Jean-Marc Hurot Jean-Claude Terrat Thierry Vanel Cyril VoVan Foued Maazoun Charles Chazot 《Hemodialysis international. International Symposium on Home Hemodialysis》2001,5(1):42-50
While nephrologists wait for the ideal, non invasive, inexpensive, precise, and reproducible tool to evaluate extracellular volume (ECV), they need to exert their clinical acumen in the quest of that holy grail, dry weight (DW). Estimation of DW using a clinical approach based on blood pressure (BP) and ECV is feasible and reliable as shown by successful experiences in various dialysis modes over more than three decades. But a need still exists to resolve difficulties associated with accurate assessment of BP (methods and circumstances of measurement, and the confounding effects of antihypertensive drugs) and ECV (evaluation of weight changes unrelated to ECV, lack of specificity and sensitivity of clinical symptoms, lag time, confusion in terminology). An essential point in clinical assessment of DW is that a normal BP is at the same time the target and the crucial index of DW achievement. For this reason, a trialand‐error “probe” process has to be used at intervals to make sure that the dry weight target point is correctly estimated. The various “non clinical” methods proposed for dry weight assessment increase the complexity and the cost of hemodialysis. They are, in the present state of things, more clinical research than practice tools. They do not replace clinical judgment. 相似文献
88.
The principle of an ultrasonic nebulizer is based on the vibrations of a piezoelectric crystal driven by an alternating electrical field. These periodic vibrations are characterized by their frequency, their amplitude, and their intensity, which corresponds to the energy transmitted per surface unit. When the vibration in tensity is sufficient, cavitation occurs, and droplets are generated. Ventilation enables airflow to cross the nebulizer and to expel the aerosol droplets. For a given nebulizer, the vibration frequency of the piezoelectric crystal is fixed, often in the range 1-2.5MHz. In most cases, an adjustment in vibration intensity is possible by modifying vibration amplitude. The ventilation level is adjustable. The vibrations may be transmitted through a coupling liquid--commonly water--to a nebulizer cup containing the solution to be aerosolized. In this work, we studied the influence of the technological parameters of ultrasonic nebulization on nebulization quality. Our study was carried out with a 9% sodium chloride solution and a 2% protein solution (alpha1 protease inhibitor). Three different ultrasonic nebulizers were used. An increase in vibration frequency decreased the size of droplets emitted. The coupling liquid absorbed the energy produced by the ultrasonic vibrations and canceled out any heating of the solution, which is particularly interesting for thermosensitive drugs. An increase in vibration intensity did not modify the size of droplets emitted, but decreased nebulization time and raised the quantity of protein nebulized, thus improving performance. On the other hand, an increase in ventilation increased the size of emitted droplets and decreased nebulization time and the quantity of protein nebulized because more drug was lost on the walls of the nebulizer. High intensity associated with low ventilation favors drug delivery deep into the lungs. 相似文献
89.
Russell G. Smith William F. Reiter Guillaume Vitupier Steven C. Lovejoy 《Canadian Metallurgical Quarterly》2005,10(1):5-11
Stress analysis of the components of a sheave used to transfer loads between the lift span and counterweight in a movable span bridge is investigated. Stress analysis is a requirement for properly designing such sheaves. Modeling of the mechanism of load transfer from the wire ropes to the sheave is accomplished in three ways: (1) the traditional manner using a uniform pressure distribution; (2) using a varying pressure distribution developed from belt/pulley theory; and (3) using the finite-element method with nonlinear contact elements between the wire rope and the sheave. Internal stresses in the sheave are calculated using uniform distributed pressure and a varying pressure distribution. It is determined that the load distribution on the sheave from the wire ropes is precisely the same for the nonlinear contact analysis and the belt/pulley analysis. The internal stress analysis results show that the traditional, uniformly distributed load representation is less conservative than the more realistic belt/pulley load representation. A methodology is developed that can be utilized to more accurately model the load transfer representation without the complexity of nonlinear analyses. 相似文献
90.
Guillaume Bernard-Granger Christian Guizard Laurie San-Miguel 《Journal of the American Ceramic Society》2007,90(9):2698-2702
Sintering in air of a pure yttria powder was investigated on green samples shaped by slip casting. The "relative density/grain size" trajectory has been drawn and hypotheses concerning the mechanisms controlling grain growth and densification were formulated. Samples were fully densified by an additional hot isostatic pressing step on pre-sintered samples. After optimal polishing, optical properties were measured in the UV, visible, and infrared ranges. 相似文献