19 research outputs found

    L’influence de l’anglais sur l’apprentissage des articles en français : une étude de cas

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    L’objectif de ce mémoire de master est d’aborder l’influence d’une langue étrangère antérieurement apprise (L2) sur l’apprentissage d’une autre langue étrangère (L3). Dans cette recherche, nous avons voulu étudier l’influence de l’anglais (L2) sur l’apprentissage du français (L3). Le sujet de recherche se délimite à l’examination des articles en français dont l’usage diffère de celle des articles en anglais, de même que le fait le finnois qui ne comprend pas des articles (L1). Au début de l’étude, nous présumons que la langue L2 influera sur l’usage de la langue L3. Notre recherche est une étude qualitative car nous nous sommes intéressée par examiner un phénomène du transfer translinguistique et son impact sur l’emploi des articles en français. Pour étudier ce phénomène, nous avons collecté un corpus composant des rédactions écrites, du produit fini et du processus, par 5 étudiants finnophones de niveau universitaire qui ont commencé l’apprentissage de l’anglais avant des études du français. En outre, les étudiants ont rempli un questionnaire sur Webropol à propos de leurs connaissances langagières qui nous rend possible d’examiner plus profondément les résultats émergeant dans les rédactions. La collecte de notre corpus a été réalisée avec l’aide du logiciel ScriptLog qui a enregistré tout le processus d’écriture des participants. Dans la partie théorique, nous expliquons le système des articles en français et en anglais. Pour traiter le système des articles an français, nous recourons aux manuels des grammaires du français (Kalmbach, 2020 ; Poisson-Quinton et al., 2019). La présentation du système des articles en anglais s’appuie sur la grammaire de l’anglais (Biber, Conrad et Leech, 2002). Nous présentons également des notions (transfert translinguistique et intralinguistique) qui sont étroitement liées à notre recherche. Les résultats ont montré que l’influence de l’anglais sur le choix de l’article en français est insignifiante comparée à nos expectatifs. Selon les résultats, nous ne pouvons pas clairement conclure que le choix des articles en français a été influencé par la connaissance des regles des articles en anglais. Les résultats indiquent plutôt qu’il s’agirait de l’influence intralinguistique, en d’autres termes que la connaissance du français et les règles de la grammaire française impliquent sur le choix de l’article en français dans notre petit corpus

    Kinetics of CO2 absorption into aqueous solutions of 3-dimethylamino-1-propanol and 1-(2-hydroxyethyl)pyrrolidine in the blend with 3-(methylamino)propylamine

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    The kinetics of CO2 absorption into unloaded aqueous solutions of 3-dimethylamino-1-propanol (3DMA1P) and 1-(2-hydroxyethyl)pyrrolidine (1-(2HE)PRLD) blended with 3-(methylamino)propylamine (MAPA) were studied in the temperature range of 29–63 °C using a string of discs contactor. In addition, density and viscosity of the blended amines were measured in the temperature range of 25–80 °C, and N2O solubility was measured in the temperature range of 30–90 °C. The obtained results were compared with blends of 2-(diethylamino)ethanol (DEEA) and MAPA. The present study indicated that the blended amines, with varying solvent concentration, obtained comparable values for the overall mass transfer coefficient due to competing effects between solubility, diffusivity and reaction kinetics. The solubility of CO2 was higher in DEEA/MAPA than in the other blended amines, while the calculated values for the pseudo-first order kinetic constant were higher for the 3DMA1P/MAPA and 1-(2HE)PRLD/MAPA solutions than for the DEEA/MAPA solution. The pseudo-first order kinetic constants were correlated to the direct mechanism with reasonable accuracy. The contribution of the tertiary amine as a proton receiver for the MAPA-CO2 reaction represented between 53 and 70% of the pseudo-first order kinetic constant

    A review of potential amine solvents for CO2 absorption process: Absorption capacity, cyclic capacity and pKa

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    Solvent selection is an important element to enable low energy requirement in post combustion CO2 capture process by means of chemical absorption. In this paper, we investigated the CO2 capture performance of 132 different aqueous amine solvents available in the literature. The properties studied were absorption capacity, cyclic capacity and the pKa – absorption capacity relationship. In addition, fast solvent screening was critically evaluated. Based on published data, no single amine showed superior performance in terms of absorption capacity and cyclic capacity. However, most of the studied amine solvents showed a better performance than MEA. In some cases, amines studied using the different screening techniques showed results which contradicted with the equilibrium value; the screening work seemed to lead to results where the equilibrium value was exceeded. Further, it was indicated that a solvent with promising cyclic capacity with desorption at 70 °C or 80 °C, not necessarily show the same potential with desorption at 120 °C. Thus, the value of the screening experiments can be questioned. At last, it was found a linear relationship between the pKa value of an amine solvent and its absorption capacity

    Effect of liquid viscosity on the performance of a non-porous membrane contactor for CO2 capture

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    The effect of liquid viscosity on the performance of a non-porous membrane contactor is important to study for a proper solvent selection and process design. In this work, the overall mass transfer coefficient for MEA- and NaOH-based solutions was studied using a string of discs contactor in the temperature range 28–64 °C and a thin composite membrane contactor at 40 °C. Also, viscosity, density and N2O solubility of the aqueous solutions were measured in the temperature range 30–70 °C. The solvent viscosity of MEA and NaOH solutions was artificially adjusted from 0.5 to 54.7 mPa s by addition of sugar and/or glycerol. The overall mass transfer coefficient was found to decrease with increasing amount of viscosifier and the decrease seemed to be independent of the solvent system. In the membrane contactor, the decrease in the overall mass transfer coefficient was attributed to the decreasing CO2 solubility and CO2 diffusion coefficient, but as these properties alone were not able to describe the experimental values, the reason was attributed also to the establishment of an additional resistance at the membrane/liquid interface.publishedVersio

    Effect of liquid viscosity on the performance of a non-porous membrane contactor for CO2 capture

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    The effect of liquid viscosity on the performance of a non-porous membrane contactor is important to study for a proper solvent selection and process design. In this work, the overall mass transfer coefficient for MEA- and NaOH-based solutions was studied using a string of discs contactor in the temperature range 28–64 °C and a thin composite membrane contactor at 40 °C. Also, viscosity, density and N2O solubility of the aqueous solutions were measured in the temperature range 30–70 °C. The solvent viscosity of MEA and NaOH solutions was artificially adjusted from 0.5 to 54.7 mPa s by addition of sugar and/or glycerol. The overall mass transfer coefficient was found to decrease with increasing amount of viscosifier and the decrease seemed to be independent of the solvent system. In the membrane contactor, the decrease in the overall mass transfer coefficient was attributed to the decreasing CO2 solubility and CO2 diffusion coefficient, but as these properties alone were not able to describe the experimental values, the reason was attributed also to the establishment of an additional resistance at the membrane/liquid interface

    Performance of MAPA promoted tertiary amine systems for CO2 absorption: Influence of alkyl chain length and hydroxyl groups

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    Absorption and desorption of CO2 into five aqueous tertiary amine solvents and their blends with MAPA were studied using a screening apparatus. Results showed that MAPA significantly enhanced both CO2 absorption rate and absorption capacity. The solvent system with the highest CO2 absorption capacity and cyclic CO2 capacity was 3 M DEEA + 1 M MAPA with a CO2 loading of 2.72 mole CO2/kg solution and a cyclic CO2 capacity of 2.06 mole CO2/kg solution. For both the single and the blended systems, the CO2 absorption capacity decreased when increasing the number of ethanolamine groups on the tertiary amine (DEEA → EDEA → TEA) and when the alkyl chain length in the tertiary amine was increased (EDEA → BDEA). When the alkyl amine group in the tertiary amine became hindered (BDEA → t-BDEA), the CO2 absorption capacity increased

    Thermodynamic Properties of The Binary Mixture of Monoethanolamine and Carbon Dioxide

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    Homogenous densities in the liquid phase and VLE data were measured for the monoethanolamine and carbon dioxide system. The density data were obtained on five isotherms in a temperature range between 313.15 K and 353.15 K at atmospheric pressure and for two different loadings. VLE data were acquired on the isotherms 333.15 K, 353.15 K, and 373.15 K. These new data enabled the adjustment of an e-NRTL Gibbs excess model in combination with a cubic equation of state for CO2 to describe the gas phase. The model represents the partial pressure of CO2 above carbon dioxide loaded pure monoethanolamine well

    Aqueous Mapa, DEEA, and Their Blend as CO2 Absorbents: Interrelationship between NMR Speciation, pH, and Heat of Absorption Data

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    On the basis of speciation by nuclear magnetic resonance (NMR) spectroscopy, heat of absorption, and pH data, the reactions occurring in aqueous MAPA (3-(methylamino)propylamine), DEEA (2-(diethylamino)ethanol), and their blend at various carbon dioxide (CO2) loadings were identified and discussed. At increasing CO2 loading, the basicity of the solutions decreased. In the MAPA solvent, this led to the hydrolysis of the carbamate species, which corresponded to a drop in the heat of absorption. In the blend, due to the activity of DEEA, such a drop in both pH and heat of absorption was not noticeable. In the presence of MAPA, in the early loadings DEEA had not yet an influence on the (bi)carbonate formation but mainly on the MAPA activity. However, as soon as the trend for (bi)carbonate formation went as in DEEA singly, the released heat steadily decreased. Both in single and in blended MAPA, the carbamate hydrolyses started at similar pH values, i.e., about 9.8–9.5
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