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61.
62.
直链烷基苯生产工艺及市场分析 总被引:1,自引:0,他引:1
通过对大量资料的收集与整理,简述了全球直链烷基苯的生产工艺及应用情况,重点介绍了目前全球最新的直链烷基苯生产工艺——固体酸烷基化生产工艺(DETAL工艺)。同时对全球范围内直链烷基苯的供应与需求情况进行了介绍,并对直链烷基苯的未来市场进行了分析与预测。 相似文献
63.
介绍了国内首创的离子膜盐水二次精制塔工艺,运行6 a证明本工艺是投资省、见 效快,生产能力大,又切实可行的工艺方法。 相似文献
64.
在满足工艺要求的基础上,通过富集均三甲苯塔模拟与优化给出最佳操作条件,用于指导实际操作和设备改造.优化生产参数。 相似文献
65.
Mesoporous sulfated Al2O3–ZrO2 (MSAZ) catalysts with large surface areas and pore volumes after calcination at high temperature (650 °C) and with higher
Al2O3 content than 20wt% were successfully prepared from a template of block copolymer (P84). The MSAZ catalysts were characterized
by X-ray diffraction (XRD), N2 adsorption, transmission electron microscopy (TEM), 27Al magic-angle spinning nuclear magnetic resonance (MAS NMR), thermogravimetric analysis (TG–DTG), temperature-programmed
desorption of ammonia (NH3-TPD) and infrared spectra (IR) of adsorbed pyridine. It is shown that the resulting mesostructured sulfated Al2O3–ZrO2 samples have a well-developed textural mesoporosity. The number of acid sites present on MSAZ catalysts is higher than that
on conventional sulfated zirconia, and the former catalysts are more active than the latter one for various acid-catalyzed
reactions. 相似文献
66.
68.
H. J. Dutton S. B. Johnson F. J. Pusch M. S. F. Lie Ken Jie F. D. Gunstone R. T. Holman 《Lipids》1988,23(5):481-489
An approach to the analysis of 55 possible nonconjugated positional isomers of octadecadienoic acid is described and tested
with mixtures of individual synthetic methyl esters. In the first example, by ozonolysis a sevencomponent mixture consisting
ofcis,cis 5,12-, 6,10-, 6,11-, 6,12-, 7,12-, 8,12-, and 9,12-octadecadienoates was converted to aldehydes, aldehyde-esters and dialdehydes.
These fragments were separated on a 50 m×0.2 mm free fatty acid phase (FFAP) vitreous silica capillary column. Equations for
an arbitrarily restricted 12×15 matrix of linear simultaneous equations and a computer solution of the matrix provided the
composition of the initial methyl octadecadienoate mixture. The power and significance of this method became apparent with
the observation that only two of the seven isomers in the known mixture were resolved as single peaks by state-of-the-art
capillary gas chromatography, but all seven were identified and estimated with acceptable error by the ozonolysis-capillary
gas chromatography-computer procedure. In a generalized approach to the analysis of the 55 possible nonconjugated isomers,
a computer program selects the appropriate matrix of linear simultaneous equations based on the aldehyde data supplied by
the analyst. Twenty of 21 combinations of seven isomeric esters taken five at a time have been analyzed to assess the efficiency
of the method. To illustrate applicability at this stage of development, the method has been used to analyze the diene products
of the hydrazine reduction of γ-linolenic acid and the diene products from the biological desaturation of isomeric monoenes.
The possibility of distinguishing geometric and positional isomers of 18∶2 has been opened by the observed separation ofcis-andtrans-unsaturated aldehydes and aldehyde-esters.
Presented in part at the 16th World Congress of the International Society for Fat Research, October 4–7, 1983, in Budapest,
Hungary, and at the American Oil Chemists' Society Meeting, May 15, 1986, in Honolulu, Hawaii. 相似文献
69.
The PbO2 and F−-doped PbO2 (F-PbO2) film electrodes have been prepared by an electrodeposition process onto platinum substrate. The changes of their electrochemical activity for oxygen evolution (OE) reaction with accelerated electrolysis time have been studied. The results show that the activity of the electrodes decreases with increasing electrolysis time. This can be attributed to the conductivity variations, which are caused by the decrease of the oxygen vacancy concentration in PbO2 films during OE. The mechanism of the decrease of the oxygen vacancies has been investigated. For F-PbO2 film electrodes, though its electrochemical activity is somewhat lower than that of undoped one, its activity stability is much higher in comparison with that of PbO2. The influence of F− doping on the activity of PbO2 film electrodes has been also discussed. 相似文献
70.