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Warren E. Mabee David J. Gregg John N. Saddler 《Applied biochemistry and biotechnology》2005,123(1-3):765-778
The biorefinery is a key concept used in the strategies and visions of many industrial countries. The potential for Canadian
biorefineries based on lignocellulosic forest and agricultural residues is examined. The sector is described in terms of research
interests, emerging companies, and established corporate interests. It is found that the Canadian biorefining sector currently
has an emphasis on specific bioproduct generation, and the process elements required for a true sugar-based process are in
the research phase. A Canadian national strategy should focus on increasing forest industry participation, and increasing
collaboration with the provinces, particularly in western Canada. 相似文献
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Rangarani Karnati Warren T. Ford 《Journal of polymer science. Part A, Polymer chemistry》2008,46(11):3813-3819
Conventional and microwave heating were compared for free radical dispersion polymerizations of crosslinked copolymers of 2‐ethylhexyl methacrylate, vinylbenzyl chloride (VBC), and fluoroalkyl methacryate monomers in the solvent nonafluorobutyl ethyl ether, and for the functional conversion of the VBC units of the copolymer particles with trimethylamine to quaternary ammonium chloride units. By conventional heating, all polymerizations produced foamy coagulated products consisting of primary spherical particles 1–2 μm in diameter. Microwave heating using poly(1H,1H‐dihydroperfluorooctyl acrylate) as a stabilizer gave faster polymerization and stable dispersions of discrete 1 μm particles. Microwave heating also gave faster reactions of the copolymers with trimethylamine to produce quaternary ammonium chloride functionalized colloidal particles. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3813–3819, 2008 相似文献
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The rate law for the demetallation of the title indium(III)-porphin complex in aqueous acidic thiocyanate media at 3.00M ionic strength was found to be of the form where [H4P2?] is the concentration of the diacid product formed, [InP]t is the total concentration of all forms of indium(III)-porphin complex present, and a and b are constants. The constant a is a pseudo-third-order rate constant with the value (0.057 ± 0.005)M?2 s?1 and b has the value 0.704M?2 at 50.5°C. If the mechanism for demetallation involves ringpuckering with the attachment of two H+ ions, then 1/b can be identified with the product K1K2 for the stepwise dissociation of two protons from two ring pyrrolic nitrogen atoms of H2InP?. In the sulfonated tetraphenylporphin used for these studies the ring pyrrolic nitrogen atoms seem to be the most probable sites for protonation. If this identification is correct, the value of 1.42 ± 0.13 found for the product K1K2 shows the enormous effect that the presence of the In3+ center has on the ionization constants of these two protons. That the kinetic studies show saturation effects with respect to proton addition to InP3? may result from the fact that In3+ sits about 0.6 Å above the porphin ring. 相似文献
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A method is proposed by which the electronic absorption of an ion may be obtained by perturbation of a chemical equilibrium established in an ion cyclotron resonance spectrometer. 相似文献