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51.
Frank W. Mercer Matilda M. Fone Martin T. McKenzie 《Journal of polymer science. Part A, Polymer chemistry》1997,35(3):521-526
The new monomer 2,2-bis[4-(4-{4-fluorobenzoyl}-1-naphthoxy)phenyl]hexafluoropropane ( 2 ) was synthesized in a two-step reaction sequence. 2,2-his[4-(1-naphthoxy)phenyl]-hexafluoropropane ( 1 ) was prepared using the Ullmann ether synthesis reaction of 4,4-(hex-afluoroisopropylidiene)diphenol with 1-bromonaphthalene. Friedel-Crafts acylation of 1 with 4-fluorobenzoyl chloride in methylene chloride containing dimethylsulfone selectively afforded 2 in 82% yield. The polycondensation of 2 with various bisphenols in DMAc in the presence of an excess of potassium carbonate as a condensation reagent was carried out at 165°C to quantitatively afford the corresponding fluorinated poly(aryl ether ketone)s containing 1,4-naphthalene moieties. Thermal analysis of the polymers showed them to have Tgs ranging from 194 to 230°C and to be thermally stable in air up with initial weight losses at about 500°C. In addition, these novel polymers exhibited excellent solubility in organic solvents including NMP, DMAc, and chloroform. © 1997 John Wiley & Sons, Inc. 相似文献
52.
Transport pricing at the level of the firm is addressed. The numbers of full fare passengers travelling on three routes of two competing bus companies are analysed using a multiplicative discontinuous price model. Results show that generally only the operator increasing the price suffers a loss of passengers and the price elasticity is a non-linear function of the resulting price difference. The method of analysis and the results have implications for the market modelling of fast moving consumer goods. It is noted that almost no studies of transport pricing at the level of the firm have been carried out previously because of lack of data. 相似文献
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A. McD Mercer 《Acta Mathematica Hungarica》1976,27(3-4):313-317
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A. McD. Mercer 《Acta Mathematica Hungarica》1979,34(3-4):293-296
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A generalized model, which has been found to be of practical value, is developed to represent the process of selling to consumers by retailers. The concepts of consumers' preferences and products' attributes and availabilities are formalized, quantified probabilistically and related to provide expressions for the time-dependent sales of all competing brands. 相似文献
60.
Dr. Edgardo M. Gavilán-Arriazu Dr. Michael P. Mercer Daniel E. Barraco Prof. Harry E. Hoster Prof. Ezequiel P. M. Leiva 《Chemphyschem》2022,23(2):e202100700
Understanding and optimizing single particle rate behaviour is normally challenging in composite commercial lithium-ion electrode materials. In this regard, recent experimental research has addressed the electrochemical Li-ion intercalation in individual nanosized particles. Here, we present a thorough theoretical analysis of the Li+ intercalation voltammetric behaviour in single nano/micro-scale LiMn2O4 (LMO) particles, incorporating realistic interactions between inserted ions. A transparent 2-dimensional zone diagram representation of kinetic-diffusional behaviour is provided that allows rapid diagnosis of the reversibility and diffusion length of the system depending on the particle geometry. We provide an Excel file where the boundary lines of the zone diagram can be rapidly recalculated by setting input values of the rate constant, and diffusion coefficient, . The model framework elucidates the heterogeneous behaviour of nanosized particles with similar sizes but different shapes. Hence, we present here an outlook for realistic multiscale modelling of real materials. 相似文献