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81.
We present the clinical outcome and imaging micro and macroscopic of a patient who died of e liver acute failure. Hodgkin disease with massive infiltration was found at necropsy. We offer a review of the liver complaint in this particular disease.  相似文献   
82.
Renewable‐based lubricants are being considered as potential alternatives to petroleum‐based lubricants for various reasons, mainly increased environmental sensitivity. However, understanding the tribological performance of such vegetable‐based lubricants under elevated temperatures is critical for their industrial implementation. This study focuses on the friction and abrasion rate characteristics of soybean and sunflower base oils in comparison to a base mineral oil under sliding wear at elevated temperatures. It was found that the abrasion rate and friction were less severe for the vegetable‐based lubricants up to temperatures around 100°C. The observed performance of the vegetable‐based lubricants was verified using a kinetic reaction mechanism model of lubricant degradation. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
83.
The particle formation and emission in the combustion of pulverized olive residue (orujillo) is studied in this work. The fuel has been burned in controlled combustion conditions in an entrained flow reactor. A bimodal distribution with mode peaks at 155 nm and 110 μm is found for fly ashes. Coarse particles have been characterized by laser diffractometry and SEM, while fines have been analyzed by low-pressure impaction, DMA, SEM, and X-ray diffraction. Particles with Dp < 1 μm are composed of only K2SO4 and KCl in the same mass proportion, and possibly K3PO4 (less than 7% in mass). The use of a new particle sampling probe and a TEM allowed a detailed study of the formation of these particles when flue gases cool down. K2SO4 is experimentally found to start nucleation over 900°C, while KCl is not observed at this temperature. Condensation of KCl on these nuclei is observed in a sample taken at 560°C. These “formation steps” are in good agreement with both theoretical calculations by other authors and a simple equilibrium schema shown here.  相似文献   
84.
85.
Epoxidized 10-undecenoic acid triglyceride, an experimental seed oil derivative that has a terminal epoxy group on each of the three acyl glyceride segments, has been found to have good reactivity with amine curatives and allows room temperature cures to be obtained. Coatings based on epoxidized 10-undercenoic acid triglyceride have also shown excellent UV stability. As an example, coatings samples placed in a QUVA chamber exhibit no loss in gloss after 3000 hr of a cycled exposure to high intensity UV lamps and moisture at temperatures of 50–60°C. In comparison, coatings based on standard liquid epoxy resins (LERs) and commercially available hydrogenated LERs lose gloss due to chalking/decomposition within 200–800 hr. Presented at the 81 st Annual Meeting of the Federation of Societies for Coatings Technology, November 12–14, 2003, in Philadelphia, PA.  相似文献   
86.
Granule impact deformation has long been recognised as important in determining whether or not two colliding granules will coalesce. Work in the last 10 years has highlighted the fact that viscous effects are significant in granulation. The relative strengths of different formulations can vary with strain rate. Therefore, traditional strength measurements made at pseudo-static conditions give no indication, even qualitatively, of how materials will behave at high strain rates, and hence are actually misleading when used to model granule coalescence. This means that new standard methods need to be developed for determining the strain rates encountered by granules inside industrial equipment and also for measuring the mechanical properties of granules at these strain rates. The constitutive equations used in theoretical models of granule coalescence also need to be extended to include strain-rate dependent components.  相似文献   
87.
A method to produce nanocomposite polymer electrolytes consisting of poly(ethylene oxide) (PEO) as the polymer matrix, lithium tetrafluoroborate (LiBF4) as the lithium salt, and TiO2 as the inert ceramic filler is described. The ceramic filler, TiO2, was synthesized in situ by a sol–gel process. The morphology and crystallinity of the nanocomposite polymer electrolytes were examined by scanning electron microscopy and differential scanning calorimetry, respectively. The electrochemical properties of interest to battery applications, such as ionic conductivity, Li+ transference number, and stability window were investigated. The room‐temperature ionic conductivity of these polymer electrolytes was an order of magnitude higher than that of the TiO2 free sample. A high Li+ transference number of 0.51 was recorded, and the nanocomposite electrolyte was found to be electrochemically stable up to 4.5 V versus Li+/Li. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2815–2822, 2003  相似文献   
88.
Copper and iron in glasses constitute classical aims of study because of the optical effects that they produce. Structured materials are also interesting due to the incorporated functionalities derived from their spatial organization. Here, CuO and Fe2O3 were incorporated into a standard glass, from which glass coatings with different thicknesses were studied. Whereas iron cations dissolved in the glassy matrix, copper cations saturated it and crystallized at the surface, forming a hierarchical microstructure. The surface microstructure consisted of crystallizations of Tenorite (CuO) forming interconnected walls. The walls surrounding areas of glassy matrix gave rise to a cells microstructure. Rutherford Backscattering Spectrometry provided the composition of the samples with high depth resolution, and Raman Confocal Microscopy determined the phases location and their distribution forming the microstructure. The joint information from both techniques allowed high chemical and spatial resolution of the main cations location for the hierarchical surface microstructure.  相似文献   
89.
90.
A new approach for the incorporation of safety criteria into the selection, location, and sizing of a biorefinery is introduced. In addition to the techno‐economic factors, risk metrics are used in the decision‐making process by considering the cumulative risk associated with key stages of the life cycle of a biorefinery that includes biomass storage and transportation, process conversion into biofuels or bioproducts, and product storage. The fixed cost of the process along with the operating costs for transportation and processing as well as the value of the product are included. An optimization formulation is developed based on a superstructure that embeds potential supply chains of interest. The optimization program establishes the tradeoffs between cost and safety issues in the form of Pareto curves. A case study on bio‐hydrogen production is solved to illustrate the merits of the proposed approach. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2427–2434, 2013  相似文献   
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