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91.
Milk fat fractionation today: A review 总被引:2,自引:0,他引:2
E. Deffense 《Journal of the American Oil Chemists' Society》1993,70(12):1193-1201
Although anhydrous milk fat (AMF) has excellent properties, its variable physicochemical properties and its lack of functionality
restrict its uses in the food industry. A technology involving dry fractionation of AMF has been developed, and its attributes
include selectivity, reliability and general application. Combining two simple and reliable technologies,i.e., multi-step fractionation and blending, it is possible to overcome functionality problems and the seasonal variations of
AMF.
Lecture presented at the joint meeting of the International Society for Fat Research and the American Oil Chemists’ Society
in Toronto, May 10, 1992. 相似文献
92.
比较了几种不同形式气柜的优缺点,中国石化沧州分公司炼油厂选用了卷帘型干式气柜对瓦斯气进行回收和储存。该气柜主要借助于一种柔性的橡胶密封材料将气柜侧板和活塞密封连接。介绍了该气柜的设计参数、结构和运行原理,详述了瓦斯自动放散管的作用。讨论分析了气柜运行事故隐患,并提出相应的防范措施,最后针对气柜运行过程中存在的问题提出了整改措施。 相似文献
93.
《Journal of Manufacturing Systems》2014,33(4):498-507
Virtual manufacturing systems can provide useful means for products to be manufactured without the need of physical testing on the shop floor. As a result, the time and cost of part production can be decreased. There are different error sources in machine tools such as tool deflection, geometrical deviations of moving axis and thermal distortions of machine tool structures. Some of these errors can be decreased by controlling the machining process and environmental parameters. However other errors like tool deflection and geometrical errors which have a big portion of the total error, need more attention. This paper presents a virtual machining system in order to enforce dimensional, geometrical and tool deflection errors in three-axis milling operations. The system receives 21 dimensional and geometrical errors of a machine tool and machining codes of a specific part as input. The output of the system is the modified codes which will produce actual machined part in the virtual environment. 相似文献
94.
K Harmsen 《Nutrient Cycling in Agroecosystems》1984,5(4):371-382
Agronomic efficiency (AE) is defined as the increase in economic yield of a crop per unit fertilizer applied. Components of AE are physiological efficiency and apparent recovery fraction. The latter can be further separated into uptake efficiency and availability index. Ways to increase the nitrogen fertilizer use efficiency in rainfed agriculture through fertilizer management are discussed. 相似文献
95.
96.
Sorption of sulfur dioxide (SO2) was carried out on calcium‐based sorbents under dynamic conditions in a fixed bed. The experimental conditions were reaction temperature (700 to 1000°C), SO2 concentration (1000‐10 000 ppm), sorbent particles size (1 to 2 mm) and the types of sorbents (hydroxide or carbonate). The sorption process was found to be effective at low concentration levels (less than 10 000 ppm) as the breakthrough time significantly decreased with increase in concentration. The maximum removal of SO2 was observed at a reaction temperature of 950°C. The hydroxide‐based sorbents of relatively smaller particle size were found to exhibit superior sorption performance in terms of longer breakthrough time and higher sulfate conversion. A mathematical model developed, assuming a porous structure of the sorbent materials, attributed the low sulfation conversion during SO2 sorption due to a pore diffusion mechanism. 相似文献
97.
介绍氨纶干法纺丝技术中纺丝介质 (SM )循环系统的主要设备 ,对循环风压力、风温度和风量控制进行了探讨。严格控制SM循环工艺参数 ,可减少并丝现象。 相似文献
98.
转炉干法除尘蒸发冷却器出口烟气温度大多数采用常规串级控制方式,但转炉冶炼前期控制效果并不理想.对转炉冶炼过程及蒸发冷却器出口烟气温度的控制难点进行研究,找出常规串级控制方式的缺点,并设计出一种智能混合控制器.采用智能模糊控制器和常规控制器并联的控制方式,对蒸发冷却器出口烟气温度进行控制,控制效果理想.实际应用表明,同常规串级控制器相比,智能混合控制器具有响应快、被控对象稳定等优点. 相似文献
99.
100.
Meso-porous Al2O3-supported Ni catalysts exhibited the highest activity, stability and excellent coke-resistance ability for CH4 reforming with CO2 among several oxide-supported Ni catalysts (meso-porous Al2O3 (Yas1-2, Yas3-8), -Al2O3, -Al2O3, SiO2, MgO, La2O3, CeO2 and ZrO2). The properties of deposited carbons depended on the properties of the supports, and on the meso-porous Al2O3-supported Ni catalyst, only the intermediate carbon of the reforming reaction formed. XRD and H2-TPR analysis found that mainly spinel NiAl2O4 formed in meso-porous Al2O3 and -Al2O3-supported catalysts, while only NiO was detected in -Al2O3, SiO2, CeO2, La2O3 and ZrO2 supports. The strong interaction between Ni and meso-porous Al2O3 improved the dispersion of Ni, retarded its sintering and improved the activated adsorption of CO2. The coking reaction via CH4 temperature-programed decomposition indicated that meso-porous Al2O3-supported Ni catalysts were less active for carbon formation by CH4 decomposition than Ni/-Al2O3 and Ni/-Al2O3. 相似文献