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61.
Yoshitsugu Kosugi Tsutomu Kunieda Naoki Azuma 《Journal of the American Oil Chemists' Society》1994,71(4):445-448
Rice bran oil containing 30–50% free fatty acid was continually converted to an oil containing more than 75% of triacylglycerol
(TG) by means of immobilized lipase. The reaction was carried out at 60°C for 24 h with dehydration and reactant mixing by
dry nitrogen flow under a positive nitrogen atmosphere. Enzymatic TG synthesis with evaporation by heating was not suitable
because of the increasing peroxide value of the oil.
Part of this article was presented at the annual meeting of the Japan Oil Chemists' Society at Sendai, Japan, October, 16,
1990. 相似文献
62.
Kanit Krisnangkura 《Journal of the American Oil Chemists' Society》1991,68(1):56-58
Equations were developed for the estimation of gross heat of combustion (HG) of triglycerides (TGs) and fatty acid methyl
esters (FAMEs) from their saponification number (SN) and iodine value (IV). HG of TG=1,896,000/SN − 0.6 IV — 1600 and HG of
FAME=618,000/SN − 0.08 IV — 430. When these equations were tested on cottonseed oil, soybean oil, partially hydrogenated soybean
oil, peanut oil, sunflower oil, sunflower oil methyl esters, soybean oil methyl esters and cottonseed oil methyl esters, predicted
HG values agreed well with those reported in the literature. 相似文献
63.
To evaluate the wear condition of machines accurately,oil spectrographic entropy,mutual information and ICA analysis methods based on information theory are presented. A full-scale diagnosis utilizing all channels of spectrographic analysis can be obtained. By measuring the complexity and correlativity,the characteristics of wear condition of machines can be shown clearly. The diagnostic quality is improved. The analysis processes of these monitoring methods are given through the explanation of examples. The availability of these methods is validated and further research fields are demonstrated. 相似文献
64.
65.
In situ esterifications of high-acidity rice bran oil with methanol and ethanol and with sulfuric acid as catalyst were investigated.
In the esterification with methanol, all free fatty acids (FFA) dissolved in methanol were interesterified within 15 min,
and it was possible to obtain nearly pure methyl esters. The amount of methyl esters obtained from a given rice bran was dependent
on the FFA content of the rice bran oil. In the esterification with ethanol, it was not possible to obtain pure esters as
in methanol esterification, because the solubilities of oil components in ethanol were much higher than those in methanol. 相似文献
66.
The effects of coupling agents, silicone oil, and three types of polymeric modifiers on the mechanical properties of linear low density polyethylene (LLDPE) composites highly filled with aluminium hydroxide [Al(OH)3] were studied. Polymeric modifiers that contain polar groups, such as silane‐grafted polyethylene (Si‐g‐PE) and acrylic‐acid‐grafted ethylene‐vinyl acetate copolymer (AA‐g‐EVA), improve the mechanical properties dramatically, while nonpolar modifiers improve them to some extent. When Al(OH)3 was treated using a titanate coupling agent, the silicone oil increased the impact strength and elongation at break of the LLDPE/Al(OH)3 composites. Introduction of a polymeric modifier containing polar groups destroys the beneficial effects of silicone oil on film mechanical properties, while the introduction of a nonpolar elastomeric polymeric modifier retains the high impact strength and elongation at break. SEM analyses provide the indirect evidence of the encapsulation of silicone oil around the filler. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 121–128, 2002 相似文献
67.
在定量液压泵供油的系统中给出进、旁油路联合调速的回路,通过对2种进、旁油路联合调速的定量分析,推导出理论计算依据,得出这2种进、旁油路联合调速的调速特点。 相似文献
68.
The oxidation of Ni to NiO in solid oxide fuel cell (SOFC) anode will result in large bulk volume change, which may change the interfaces of the two phases in the anode cermet and thus may cause significant performance degradation. The reduction and oxidation (redox) of the Ni/YSZ cermet were studied at 800 ℃. Anodic polarization measurements were performed before and after redox cycles. The anode current density at an overpotential of 100 mV kept decreasing during the whole redox treatment. It decreased from 19.11 to 7.95 mA·cm-2 after two redox cycles. Anode supported unit cell was assembled for cell's discharge measurements. Cell performance declined after each redox cycle. The maximum power density decreased from 126.28 to 40.32 mW·cm-2 . The microstructural changes after redox cycling were recorded using scanning electron microscopy (SEM). The results reveal that after re-oxidation, the Ni gets coarse and has a higher porosity; the nickel network structure turns to be desultory. 相似文献
69.
对堆芯熔化条件下锆合金包壳腐蚀动力学有关问题的讨论 总被引:1,自引:0,他引:1
张喜燕 《稀有金属材料与工程》1994,23(2):14-18
针对在堆芯熔化条件下建立铝合金包壳腐蚀动力学模型时所涉及的有关问题和已有的模型进行了讨论和评述。 相似文献
70.
H.?H.?ParkEmail author M.?H.?Lee J.?S.?Yoon I.?S.?Bae B.?I.?Kim 《Metals and Materials International》2003,9(3):311-317
STS310S and SC-STS310S (simultaneously co-deposited chromium and aluminum onto 310S austenitic stainless steel substrate by
pack-cementation process) were used as separator materials on the cathode side of a molten carbonate fuel cell. With the STS310S,
corrosion proceeded via three steps; a formation step of unstable corrosion product, a protection step against corrosion until
breakaway, and an advance step of corrosion after breakaway. The final corrosion product was LiFeO2 and the loss of mass was 6.5 mg/cm2 after a corrosion test of 480 hr at 650°C. The SC-STS310S showed more effective corrosion resistance, however, than did common
STS310S. There was especially no corrosion loss on the SC-STS310S after the 480 hr corrosion test. It is anticipated that
it will be very useful as an alternative separator on the cathode side off the MCFC in the future. 相似文献