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991.
The purpose of this study is to prepare a diffusion model of the new international accounting standards known as the international financial reporting standards (IFRS). This model fits within the neo-institutional conceptual framework; more specifically, we used the DiMaggio/Powell analytical grid. Our desire to prepare this model was born from the observation that the analytical framework that is generally used to study the adoption of these new standards is the neo-institutional framework and that the principal methodologies implemented are qualitative. The question addressed in this study regards the forces leading an agent—in this case, an organisation providing standards for accounting—to adopt, at a given moment, these new standards. Existing studies, as interesting as they might be, are devoted to the question of adoption and leave aside the question of diffusion. In other words, the evolution of the system as a whole in time is ignored. Constructing a model appeared to us to be a way to move beyond these limitations. This model allows us to formalise the forces at work in the DiMaggio/Powell representation and to simulate the diffusion processes of the IFRS. To this end, we implement a multi-agent simulation. The various simulation scenarios are then compared to the observed diffusion of the IFRS. 相似文献
992.
993.
Joachim Schick Philippe Caullet Jean-Louis Paillaud Jo?l Patarin Stéphanie Freitag Claire Mangold-Callarec 《Journal of Porous Materials》2012,19(4):405-414
The phosphate adsorption kinetics are determined in batch-wise (noted B) and fixed-bed column (noted C) experiments on a Surfactant-Modified Zeolite (SMZ) and various Ca-zeolites. The influence of phosphate concentration (0.08 or 0.8?mmol/L), presence of NO3 ?, HCO3 ?, SO4 2? and Cl? competing anions (individual concentration?=?0.8?meq/L) and flow rate Q (1?C30?mL/min) is studied. Preliminary experiments lead to the selection of the most efficient Ca-LTA and SMZ samples for the subsequent studies. In B experiments, the nature of the used system does not influence the equilibrium removal rate R (??80%) but affects the adsorption kinetics. The equilibrium times are shorter on SMZ than on Ca-LTA, increasing with the phosphate concentration and the presence of competing anions, respectively in the ~0.5?C6 or ~3?C24?h ranges. In C experiments, the phosphate uptake performances on SMZ are higher than in the corresponding B experiments, with in particular higher final q/qm values. The deterioration of the performances on SMZ in presence of competing anions or with increase of Q is due to the effect of the slow phosphate ion-exchange kinetics and the short used contact time. For similar reasons, sorption on Ca-LTA is lower than on SMZ. For instance, with a 0.8?mmol/L phosphate concentration and a 10?mL/min flow rate, the time-decreasing R values become close to 50 and 10% after filtration of 10 bed-volumes respectively in presence of SMZ and Ca-LTA. Globally, SMZ is clearly more efficient than Ca-LTA, being furthermore a versatile and easily regenerable material. 相似文献
994.
995.
Zine Derhoumi Philippe Mandin Hervé Roustan Rolf Wüthrich 《Journal of Applied Electrochemistry》2013,43(12):1145-1161
During two-phase electrolysis, bubble production occurs at one or two electrodes. This yields a large change for the electrolyser electrical and hydrodynamic properties. Under normal Earth gravity, the bubble production at the electrodes induces a macro-convection in the electrolyser. This leads to a modified local current density distribution at the electrodes. When gravity is avoided, bubbles are no longer subject to buoyancy forces and to the induced natural flow friction forces. Electrolysis was performed using a potentiostat, and gas bubble evolution was observed with cameras. Quantitative evolution laws for the electrochemical cell voltage, bubble diameter and population during two-phase electrolysis are established in function of the current density and gravity variation. 相似文献
996.
Aberrant expression of glycosphingolipids is a hallmark of cancer cells and is associated with their malignant properties. Disialylated gangliosides GD2 and GD3 are considered as markers of neuroectoderm origin in tumors, whereas fucosyl-GM1 is expressed in very few normal tissues but overexpressed in a variety of cancers, especially in small cell lung carcinoma. These gangliosides are absent in most normal adult tissues, making them targets of interest in immuno-oncology. Passive and active immunotherapy strategies have been developed, and have shown promising results in clinical trials. In this review, we summarized the current knowledge on GD2, GD3, and fucosyl-GM1 expression in health and cancer, their biosynthesis pathways in the Golgi apparatus, and their biological roles. We described how their overexpression can affect intracellular signaling pathways, increasing the malignant phenotypes of cancer cells, including their metastatic potential and invasiveness. Finally, the different strategies used to target these tumor-associated gangliosides for immunotherapy were discussed, including the use and development of monoclonal antibodies, vaccines, immune system modulators, and immune effector-cell therapy, with a special focus on adoptive cellular therapy with T cells engineered to express chimeric antigen receptors. 相似文献
997.
998.
Hamza Hajjaji Sergey Alekseev Gérard Guillot Nicholas P Blanchard Virginie Monnier Yann Chevolot Georges Brémond Michel Querry David Philippon Philippe Vergne Jean Marie Bluet 《Nanoscale research letters》2014,9(1):94
Silicon nanoparticles (Si NPs) with a diameter size ranging from 4 to 8 nm were successfully fabricated. They exhibit a visible photoluminescence (PL) due to the quantum confinement effect. Chemical functionalization of these Si NPs with alkyl groups allowed to homogeneously disperse them in nonpolar liquids (NPLs). In comparison to most of literature results for Si NPs, an important PL peak position variation with temperature (almost 1 meV/K) was obtained from 303 to 390 K. The influence of the liquid viscosity on the peak positions is also presented. These variations are discussed considering energy transfer between nanoparticles. The high PL thermal sensitivity of the alkyl-capped Si NPs paves the way for their future application as nanothermometers. 相似文献
999.
Masakazu Ito Sylvain Lespinats Jens Merten Philippe Malbranche Kosuke Kurokawa 《Progress in Photovoltaics: Research and Applications》2016,24(2):159-174
Although the Sahara region has a high potential for solar power plants, the amount of installed photovoltaic (PV) system remains relatively low. This paper aims to evaluate these potentials of PV system installation in terms of environmental and economic viewpoints with indices of cost, energy, and greenhouse gas (GHG) emission. Two 1‐GW very large‐scale PV systems are simulated at Ouarzazate in Morocco and at Carpentras in France. The evaluation was performed using life cycle assessment. The lowest energy consumption and GHG emission are obtained while assuming cadmium telluride module. The result of our simulation shows that energy payback time is 0.9 years and CO2 emission rate is 27.4 g‐CO2‐eq/kWh in the Ouarzazate case. In cost estimation, generation costs are 0.06 USD/kWh in Ouarzazate and 0.09 USD/kWh in Carpentras in the case of 3% interest rate and 0.5 USD/W for multicrystalline silicon PV module price. In addition, by adapting 15% internal rate of return for 20% of budget, the generation costs become 0.09 USD/kWh in Ouarzazate and 0.13 USD/kWh in Carpentras under the same condition. Furthermore, the selection for suitable locations to install solar power plants in term of GHG emission is identified using geographical information system. Very high‐potential locations (lower than 38 g‐CO2‐eq/kWh) could be obtained in North Chili, east and west Sahara, and Mexico. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
Nano-Micro Letters - A facile and rapid method to synthesize graphene/layered double hydroxide (LDH) nanohybrids by a microwave technique is demonstrated. The synthesis procedure involves... 相似文献