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Pointe-Claire, Canada

Dwivedi P.,Yale University | Bailis R.,Yale University | Bush T.G.,University of Florida | Marinescu M.,FP Innovations
Bioenergy Research

This study attempts to determine global warming impact (GWI) of imported wood pellets from the Southern United States for electricity production in The Netherlands. An attempt is also made to determine GWI of utilizing produced wood pellets within the state of Florida for electricity generation instead of exports. A life-cycle approach is adopted to determine overall GWIs of both the cases. Economic objectives of forest landowners are also incorporated to determine biomass (pulpwood and harvesting residues) availability from a hectare of slash pine plantation. The GWI of a unit of electricity produced at a power plant located at Geertruidenberg, The Netherlands and Gainesville, Florida was 296.4 and 177.5 g of carbon dioxide equivalent greenhouse gas, respectively. An overall saving of 72.6% in greenhouse gas emissions was estimated for every kilowatt-hour of electricity generated using imported wood pellets in The Netherlands when compared with coal-based electricity. This value was found to be 82.4% if produced wood pellets are utilized within Florida for electricity generation instead of exports. A need exists to evaluate the potential of other feedstocks for wood pellet production like understory forest biomass. Additionally, macroeconomic and ecological impacts of utilizing forest biomass for wood pellet production needs to be quantified. © 2011 Springer Science+Business Media, LLC. Source

Li Y.-F.,Northeast Forestry University | Liu Y.-X.,Northeast Forestry University | Wang X.-M.,FP Innovations | Wu Q.-L.,Louisiana State University | And 2 more authors.
Journal of Applied Polymer Science

Wood-polymer composites (WPCs) were prepared from poplar wood (P. ussuriensis Komarov) in a two-step procedure. Maleic anhydride (MAN) was first dissolved in acetone and impregnated into wood; this was followed by a heat process; and then, glycidyl methacrylate (GMA) and styrene (St) were further impregnated into the MAN-treated wood, followed by a second thermal treatment. Finally, the novel WPC was fabricated. The reactions occurring in the WPC, the aggregation of the resulting polymers, and their interaction with the wood substrate were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and dynamic mechanical analysis. The performance of WPC was also evaluated in terms of the mechanical properties and durability, which were then correlated with the structural analysis of the WPC. The test results show that MAN and GMA/St chemically reacted with the wood cell walls in sequence, and the quantity of hydroxyl groups in the wood cell walls was evidently reduced. Meanwhile, St copolymerized with GMA or MAN, and the resulting polymers mainly filled in the wood cell lumen in an amorphous form, tightly contacting the wood cell walls without noticeable gaps. As a result, the mechanical properties, decay resistance, and dimensional stability of the WPC were remarkably improved over those of the untreated wood, and its glass-transition temperature also increased. © 2010 Wiley Periodicals, Inc. Source

Shopsowitz K.E.,University of British Columbia | Hamad W.Y.,FP Innovations | MacLachlan M.J.,University of British Columbia
Journal of the American Chemical Society

Nanocrystalline cellulose (NCC) has been used to template ethylene-bridged mesoporous organosilica films with long-range chirality and photonic properties. The structural color of the organosilica films results from their chiral nematic ordering, can be varied across the entire visible spectrum, and responds to the presence of chemicals within the mesopores. To synthesize these materials, acid hydrolysis was used to remove the NCC template without disrupting the organosilica framework. The resulting mesoporous organosilica films are much more flexible than brittle mesoporous silica films templated by NCC. These materials are the first of a novel family of chiral mesoporous organosilicas with photonic properties. © 2011 American Chemical Society. Source

Human walking generates vibrations and impact sound in lightweight wood-joisted floor-ceiling assemblies. Design methods were developed to successfully control the feelable vibrations. Construction solutions and materials have been developed to successfully control high frequency impact sound transmission, but not low-frequency footstep noise. This paper presents two cases of unsatisfactory low-frequency footstep noise transmission in wood-framed floor-ceiling assemblies and discusses the limited remedies available. It also describes a research plan for unlocking the secret of low-frequency footstep impact sound transmission through wood floor-ceiling assemblies, and for developing proper construction solutions to address this issue. Source

Moiseev D.V.,University of British Columbia | James B.R.,University of British Columbia | Hu T.Q.,FP Innovations
Phosphorus, Sulfur and Silicon and the Related Elements

With the aim of learning about the synergistic effect of a combination of (HOCH 2O 4 for the bleaching of mechanical pulps, reactions of (HOCH 2) 3P (and its associated precursor, (HOCH 2) 4P +Cl -) with Na 2S 2O 4 were studied in aqueous media under Ar and in air. The secondary phosphine (HOCH 2) 2PH is the major product in a 1:1 reaction of (HOCH 2) 3P and Na 2S 2O 4 under Ar, the formaldehyde being removed in the form of HOCH 2SO 3Na and HOCH 2SO 2Na; the latter is Rongalite, itself an industrial bleaching agent. Significant amounts of the primary phosphine HOCH 2PH 2 are also seen. When the reaction is performed in air, the oxide (HOCH 2) 2P(O)H is the main product. Reaction of (HOCH 2) 4P +Cl - with Na 2S 2O 4 (even under Ar) leads to solely the oxidation products: (HOCH 2) 3PO, (HOCH 2) 3PS, and (HOCH 2) 2P(O)OH. 31P{ 1H} and 1H NMR spectral data for secondary and primary (hydroxymethyl)phosphines and their oxidation products are reported for the first time. The toxicity of the primary and secondary phosphines is likely to curtail their use in commercial bleaching processes. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. © 2012 Copyright Taylor and Francis Group, LLC. Source

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