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101.
针对迷宫式压缩机在含尘气体中使用所出现的使用周期短等问题 ,在压缩机进口增设水洗塔、丝网除沫器 ,并对压缩机气阀、气缸盖等相关部件进行改进 ,取得了较好的效果 相似文献
102.
Witchakorn Charusiri Withaya Yongchareon Tharapong Vitidsant 《Korean Journal of Chemical Engineering》2006,23(3):349-355
Thailand’s food manufacturing uses about 47 Million liters per year of vegetable oil. Used vegetable oil is classified as
waste, but has potential for conversion into liquid fuel. This research studied the catalytic conversion of used vegetable
oil to liquid fuel, where investigation was performed in a batch microreactor over a temperature range of 380–430 °C, initial
pressure of hydrogen gas over 10–20 bars, and reaction time of 45–90 minutes. Catalysts such as HZSM-5, Sulfated Zirconia
and hybrid of HZSM-5 with Sulfated Zirconia were used to determine the conversion and yield of gasoline fraction. The major
products obtained were liquid products, hydrocarbon gases and small amounts of solids. Liquid products were analyzed by simulated
distillation gas chromatograph and the product distribution was obtained. Hybrid catalyst HZSM-5 with Sulfated Zirconia showed
the highest yield of gasoline with a 26.57 wt% at a temperature of 430 °C, initial hydrogen pressure at 10 bars, and reaction
time of 90 minutes in the ratio of hybrid HZSM-5 with Sulfated Zirconia at 0.3: 0.7. 相似文献
103.
104.
Jose Gerde Connie Hardy Walter Fehr Pamela J. White 《Journal of the American Oil Chemists' Society》2007,84(6):557-563
Two extruded-expelled physically refined soybean oils with reduced contents of linolenic acid, ultra-low- linolenic acid (ULL,
1.5%) and low-linolenic acid (LL, 2.6%), and a extruded-expelled physically refined control oil (control, 5.3% linolenic acid)
were evaluated by frying French fries in a commercial-like setting for 6 h day−1 during 23 days. The oils became darker, increased in yellow color at the beginning, and became redder and less green throughout
the process. Free fatty acids levels were not different among the oils until day 14, after which, ULL was different from the
control for the remainder of frying. The conjugated dienoic acid values were greatest in the control. Generally, ULL and LL
oils had lower percentages of polar compounds than did the control, providing a frying life 2 days longer than the control
and ~30% increase in frying time. A trained sensory panel evaluated the French fries on days 2, 5, and 6. Buttery and potato
flavors decreased, and rancid and painty flavors increased over frying time for all products. Rancid flavor was highest in
the fries from the control oil. Overall, the ULL and LL oils performed better than did the control oil and ULL tended to perform
better than the LL. 相似文献
105.
106.
Jin-Kwang Bok Heeman Lee Jay Woo Chang Sunwon Park 《Korean Journal of Chemical Engineering》2002,19(4):545-551
This paper presents a hybrid refinery scheduling system combining mathematical programming model and expert system. Mixed-integer
linear programming models for crude oil movement between units are merged into the expert system that is for qualitative issues
concerning crude vessel unloading operations. The target problem ranging from the crude unloading to the crude charging to
distillation towers is decomposed into several module problems for efficiency. Compared with existing scheduling approaches
for oil movement, the proposed hybrid refinery scheduling system is very effective in dealing with timing decisions involving
vessel unloading operations due to the advantages of an expert system. Since the proposed scheduling system can generate solutions
so fast, it is expected to play a key role in the real processes.
This paper is dedicated to Professor Wha Young Lee on the occasion of his retirement from Seoul National University. 相似文献
107.
108.
MTBE作为调合生产高标号无铅汽油的重要的高辛烷值组分油,准确测试其辛烷值在汽油调和生产中具有重要的意义。初步探讨了MTBE研究法辛烷值的测试方法,尝试了用甲苯标准燃料做参比燃料直接测定其净辛烷值,同时也测定了MTBE的混配辛烷值,通过MTBE辛烷值的测试,了解了MTBE的调和效应,确认了在石油二厂无铅汽油调和生产中对催化汽油的MTBE的真实辛烷值约为108/RON,指导了车用无铅汽油的调和生产。 相似文献
109.
110.
汽车刹车片用改性酚醛树脂的生产 总被引:3,自引:0,他引:3
在原有的酚醛树脂生产设备上,用腰果壳油和三聚氰胺对酚醛树脂进行改性,制得的改性树脂具有较好的软化点、聚合速度、挥发度和游离酚等性能;并且热分解温度较普通酚醛树脂大大提高。用它作胶粘剂生产的汽车刹车片,冲击强度增大:磨损率降低、摩擦性能提高、产品成本也大为降低。 相似文献