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51.
52.
M. S. Miskandar Y. B. Che Man M. S. A. Yusoff R. Abdul Rahman 《Journal of the American Oil Chemists' Society》2002,79(9):931-936
The effects of scraped-surface tube cooler temperatures on the isothermal solid fat content (SFC) of palm oil margarine during
processing and on margarine consistency (yield value, g/cm2), SFC, and polymorphic changes in storage were studied. SFC was measured in the mixing tank after leaving the tube cooler
and the pin worker. The SFC at the tube cooler exit was proportional to the amount of cooling; a higher SFC was produced by
more extreme cooling treatment. The SFC of all margarines were reduced in the pin worker, and the reduction was related to
the initial SFC profile of palm oil. Margarine samples were stored at 28°C for 28 d and tested daily. Margarine processed
at 25°C in the tube cooler had the highest consistency and the least change in SFC, but by the second week crystals had transformed
into the β form. Uniform product consistency and SFC were observed in margarines processed at 20 and 15°C. These margarines
retained the β′ crystal form for 3 and 4 wk, respectively. The best palm oil margarine was obtained with a tube cooler temperature
of 15°C and a residence time of 1.8 min. 相似文献
53.
The structure of benzoxazines is similar to that of phenolic resin through thermal self‐curing of the heterocyclic ring opening reaction that neither requires catalyst nor releases any condensation byproduct. These polybenzoxazine resins have several outstanding properties such as high thermal stability and high glass transition temperature. To better understand the curing kinetics of this copolybenzoxazine thermosetting resin, dynamic and isothermal differential scanning calorimetry measurements were performed. Three models, the Kissinger method, the Flynn–Wall–Osawa method, and the Kamal method, were used to describe the curing process. Dynamic kinetic activation energies based on Kissinger and Flynn–Wall–Osawa methods are 72.11 and 84.06 KJ/mol, respectively. The Kamal method based on an autocatalytic model results in a total order of reaction between 2.66 and 3.03, depending on curing temperature. Its activation energy and Arrhenius preexponential are 50.3 KJ/mol and 7959, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 730–737, 2005 相似文献
54.
村民自治制度实施的质量,直接映射出我国基层民主政治的发展水平.分析和审视了我国村民自治实施中出现的观念难以转变、村委会直接选举的程序缺乏科学性与民主性、制度弹性过大等问题,提出从体制、机制与技术等层面加强村民自治制度的建设和创新,对于进一步完善我国村民自治制度,促进基层民主政治建设具有重要意义. 相似文献
55.
丙烯酸乙酯合成反应产物的GC/MS分析 总被引:1,自引:0,他引:1
本文叙述了丙烯酸乙酯合成产物的GC/MS分析.从分析结果看出,本应在酯化反应前除去的CH3Cl3仍有较大的含量,这也许是导致丙烯酸乙酯被氯代的原因。 相似文献
56.
Khaksar Pour Amin Chaw Seng Woo Palaiahnakote Shivakumara Tahaei Hamid Anuar Nor Badrul 《Multimedia Tools and Applications》2021,80(16):24121-24145
Multimedia Tools and Applications - Rating a video based on its content is one of the most important solutions to classify videos for audience age groups. In this regard, Film content rating and TV... 相似文献
57.
多聚焦图像融合能够融合同一场景下具有不同聚焦部分的一系列图像.为了克服多聚焦图像融合模糊特征提取中存在的不足,提出一种基于U-Net的生成对抗网络模型.首先,生成器采用U-Net和SSE对多聚焦图像的特征进行提取,并完成图像融合;其次,判别器采用卷积层对已知的融合结果和生成器生成的融合图像进行分辨;然后,损失函数采用生成器的对抗损失、映射损失、梯度损失、均方误差损失和判别器对抗损失对生成网络进行参数调节;最后,将生成器、判别器和损失函数组成生成对抗网络模型,并进行实验.Pascal VOC2012数据集作为生成对抗网络的训练集,包括近焦图像、远焦图像、映射图像和融合图像.实验结果证明,该生成对抗网络模型能够有效地提取多聚焦图像中的模糊特征,且融合图像在互信息、相位一致性和感知相似性等方面表现优异. 相似文献
58.
GeoInformatica - Urban areas are subject to multiple and very different changes, in a two- and three-dimensional sense, mostly as a consequence of human activities, such as urbanization, but also... 相似文献
59.
Zeolite NaA was successfully prepared from nickel laterite residue for the first time via a fusion-hydrothermal procedure. The structure and morphology of the as-synthesized zeolite NaA were characterized with a range of experimental techniques, such as X-ray diffraction, scanning electronic microscopy, and infrared spectroscopy. It was revealed that the structures of the produced zeolites were dependent on the molar ratios of the reactants and hydrothermal reaction conditions, so the synthesis conditions were optimized to obtain pure zeolite NaA. Adsorption of nitrogen and carbon dioxide on the prepared zeolite NaA was also measured and analyzed. The results showed that zeolite NaA could be prepared with reasonable purity, it had physicochemical properties comparable with zeolite NaA made from other methods, and it had excellent gas adsorption properties, thus demonstrating that zeolite NaA could be prepared from nickel laterite residue. 相似文献
60.