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941.
Tine Hardeman Pieter Willot Julien De Winter Thomas Josse Pascal Gerbaux Pavletta Shestakova Erik Nies Guy Koeckelberghs 《Journal of polymer science. Part A, Polymer chemistry》2014,52(6):804-809
The formation in solution of a supramolecular graft copolymer bearing conjugated blocks is demonstrated using diffusion ordered NMR spectroscopy (DOSY). A tailor‐made poly(3‐(2‐ethylhexyl)thiophene) (P3EHT) with a phenol end group is synthesized. For this purpose, the chain‐growth mechanism of the polymerization of 2‐bromo‐5‐chloromagnesio‐3‐alkylthiophenes in the presence of a Ni(dppp) catalyst (dppp = 1,3‐bis(triphenylphosphino)propane) is exploited, as it enables the use of functionalized initiators to introduce specific end groups. The so‐obtained polythiophene was subsequently mixed in solution with poly(4‐vinylpyridine) (P4VP) to enable phenol‐pyridine hydrogen bonding. The formation of the supramolecular graft copolymer is studied using DOSY‐measurements. Based on the results thereof, the amount of P3EHT attached to the P4VP is calculated and the association constant of the hydrogen bond is estimated. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 804–809 相似文献
942.
943.
944.
Automatic Mechanism and Kinetic Model Generation for Gas‐ and Solution‐Phase Processes: A Perspective on Best Practices,Recent Advances,and Future Challenges 下载免费PDF全文
Ruben Van de Vijver Nick M. Vandewiele Pierre L. Bhoorasingh Belinda L. Slakman Fariba Seyedzadeh Khanshan Hans‐Heinrich Carstensen Marie‐Françoise Reyniers Guy B. Marin Richard H. West Kevin M. Van Geem 《国际化学动力学杂志》2015,47(4):199-231
Completely automated mechanism generation of detailed kinetic models is within reach in the coming decade. The recent developments in this field of chemical reaction engineering are anticipated to lead to some groundbreaking discoveries in the future, extending our fundamental understanding and resolving many of today's society problems such as energy production and conversion, emission reduction, greener chemical production processes, etc. In the present review, the focus is on the core of these automated mechanism generation for gas‐phase and solution‐phase processes that is on how the reaction kinetics and thermodynamic and transport properties of species are estimated and calculated starting from the fundamental elements of the software. With tasks such as the definition of reaction rules and reaction families, the unambiguous representation of species, and the choice of different termination criteria, generating a good reaction mechanism is still not as simple as pressing a “run” button. One of the main challenges that still needs to be overcome is how to deal with data scarcity and the combination with affordable computational chemistry calculations seems the logical step forward. The best practices are illustrated in a butane pyrolysis case study, which also exposes the challenges in the field of automatic kinetic model generation. 相似文献
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946.
Guy Boiliat Augusto Muracchini 《NoDEA : Nonlinear Differential Equations and Applications》1996,3(2):217-230
We illustrate, in the framework of magnetohydrodynamics, an application of crossing shock formulas to a characteristic shock moving perpendicularly to the magnetic field.Supported by C.N.R. (G.N.F.M.)Supported by C.N.R. (G.N.F.M.) and MURST (Fondi Ricerche 40% and 60%) 相似文献
947.
Alberto Gambi Marino Pedrali Manfred Winnewisser Guy Guelachvili 《Journal of Molecular Spectroscopy》1985,113(1):250-261
The Doppler-limited infrared spectrum of diazirine was recorded using a high-information Fourier transform spectrometer with a resolution of 0.0054 cm?1. The rovibrational structure of the ν9 fundamental (CH2 rocking) at 1124.9144 cm?1, which is a C-type band, was analyzed in detail with extensive use of spectrum simulation and correlation diagrams. The molecular constants for the upper energy level of this band were obtained from the overall rovibrational assignment of more than 2000 transitions, which cover the region from 1070 to 1220 cm?1. 相似文献
948.
949.
Lewis S. A. E. Guy M. J. Popov S. V. Taylor J. R. 《Optical and Quantum Electronics》2000,32(2):193-196
A fibre-optic of sub-150 fs pulse with wavelength tunability from 790 to 830 nm is demonstrated. The output from a gain-switched DFB laser diode at 1552 nm is amplified and compressed in an EDFA generating a soliton-Raman continuum which was then frequency doubled. The output wavelength was tuned over a 40 nm range with very little variation in the pulse duration and output power. 相似文献
950.
Guy Giraud 《Discrete Mathematics》1976,16(1):13-38
On determine le nombre maximum de triangles bicolores quand n tend vers l'infini, soit . On prouve aussi que, pour n assez grand, plus d'un triangle sur vingt-neuf est unicolore le methode suivie est susceptible de constituer une approche du probléme posé par une conjecture d'Erdos. Sos et Turan sur le nombre maximum de triangles tricolores. 相似文献