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Doolaege EH Vossen E Raes K De Meulenaer B Verhé R Paelinck H De Smet S 《Meat science》2012,90(4):925-931
The oxidative stability of liver pâté was investigated in relation to different doses of rosemary extract (RE) and sodium nitrite. Colour stability, lipid oxidation (TBARS) and concentrations of ascorbic acid, α-tocopherol, carnosic acid and nitrite were measured on the batters before cooking and on the cooked liver pâté before and after exposure to light and air for 48 h at 4 °C. Results showed that the use of RE significantly reduced lipid oxidation, whereas it had no effect on colour stability. Ascorbic acid and nitrite concentrations were significantly higher and lower respectively when RE was added. RE dose-dependently increased the concentration of carnosic acid. Lower sodium nitrite doses resulted in significantly lower nitrite concentrations and slightly lower TBARS values. It was concluded that in liver pâté sodium nitrite levels may be lowered to 80 mg/kg without negatively affecting colour and lipid stability and that the use of RE may help in maintaining lipid stability. 相似文献
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Wouter G. van Toll Atlas F. Cook Roland Geraerts 《Computer Animation and Virtual Worlds》2012,23(6):535-546
Games and simulations frequently model scenarios where obstacles move, appear, and disappear in an environment. A city environment changes as new buildings and roads are constructed, and routes can become partially blocked by small obstacles many times in a typical day. This paper studies the effect of using local updates to repair only the affected regions of a navigation mesh in response to a change in the environment. The techniques are inspired by incremental methods for Voronoi diagrams. The main novelty of this paper is that we show how to maintain a 2D or 2.5D navigation mesh in an environment that contains dynamic polygonal obstacles. Experiments show that local updates are fast enough to permit real‐time updates of the navigation mesh. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
876.
Roland Stone Stephen Hipp Joel Barden Phillip J. Brown O. Thompson Mefford 《应用聚合物科学杂志》2013,130(3):1975-1980
Magnetic nanoparticles have continued to gather the interest of researchers due to the unique physical properties of materials found at this size scale. Herein, the production of composite magnetic fibers composed of iron oxide nanoparticles suspended in alginate is described. These materials were produced via wet spinning of a sodium alginate solution into a bath of an aqueous solution of calcium chloride. The magnetic fibers were found to have similar mechanical properties to normal alginate fibers, and exhibited superparamagnetic behavior when subjected to an external DC magnetic field. In addition, the particle loaded fibers demonstrated the potential to produce significant amounts of heat when exposed to an AC magnetic field, suggesting these new materials could be applicable to a variety of applications including magnetic hyperthermia. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1975–1980, 2013 相似文献
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Stefan Hölzer Matthias Menzel Qamer Zia Ulrich Sigmar Schubert Mario Beiner Roland Weidisch 《Polymer》2013
Blends of two elastomeric ethylene–octene copolymers with similar octene contents having a random (ORC) and a blocky architecture (OBC) are prepared by melt mixing. The thermal and mechanical properties of ORC, OBC and their blends are investigated by DSC, dynamic mechanical analysis and tensile tests. The morphology of the semi-crystalline samples is studied by AFM and WAXS. Two types of crystals have been observed: (i) Orthorhombic crystals forming lamellae with an estimated thickness of about 13 nm composed mainly of long polyethylene-like sequences of OBC that melt a temperature of about 120 °C and (ii) fringed micellar crystals with a thickness of 2–4 nm formed basically by short polyethylene-like sequences of ORC that have melting temperatures between 30 and 80 °C. The amorphous phase contains a relatively homogeneous mixture of segments of both components indicated by the relatively uniform shape of the loss modulus peaks from dymamic-mechanical measurements for all investigated copolymers and blends. ORC crystallization is hindered in blends as indicated by lower melting enthalpies. This might be related to the high octene content of the amorphous phase at the relevant crystallization temperature as well as geometrical constraints since ORC crystallization occurs in an already semi-crystalline polymer. The results of tensile tests show that the mechanical behavior can be tailored via blend composition and morphology of the semi-crystalline material. The findings clearly indicate that blending is a powerful strategy to optimize the properties of polyolefin-based copolymers. 相似文献
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Evaluation of raw coals as fuels for direct carbon fuel cells 总被引:2,自引:0,他引:2
As a promising high-temperature fuel cell, the direct carbon fuel cell (DCFC) has a much higher efficiency and lower emissions compared with conventional coal-fired power plants. In the present DCFC system, four Australian coals from Central Queensland are successfully tested at 600-800 °C. The electrochemical performances of these coals are highly dependent on their intrinsic properties, such as chemical composition, surface area, concentrations of oxygen-containing surface functional groups and the nature of mineral matter in their ashes. Impurities such as Al2O3 and SiO2 lead to an inhibitive effect during the anodic reaction in the DCFC, while CaO, MgO and Fe2O3 exhibit a catalytic effect on the electrochemical oxidation of carbon. 相似文献