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41.
The highest diffraction efficiency (DE) value after illumination and post-curing of photopolymer films were obtained at the
SeO2/Acrylamide (AA) Ratios of AA 3.0 g, SeO2 1.0 g and the DE’s were stable values of over 90%. By the addition of SeO2, the maximum DE at the initial stage of illumination was reached at 300 seconds, which suggests SeO2 slows down the photopolymerization
of. DE variation curve for the optimum composition during extendedtime illumination of 9,000 seconds resembles a sine curve
due to the combination of the monomer diffusion and the photopolymerization, and the photopolymer film expanded at about 8%
after photopolymerization due to monomer migration. 相似文献
42.
Xiaomin Yang Xiuna Wang Changhai Liang Weiguang Su Chuang Wang Zhaochi Feng Can Li Jieshan Qiu 《Catalysis communications》2008,9(13):2278-2281
The unique and significant promotion effect of water has been evidenced by the selective oxidation of benzyl alcohol to benzaldehyde over Au/TiO2 catalysts. Water has dual promotional functions in the reaction system: to help form unique microdroplets in a multiphase reaction system and to assist the oxygen adsorption and activation. The conversion of benzyl alcohol at a molar ratio of water to solvent (p-xylene) of 7 is 7 times higher than in the absence of water. The present work has highlighted the potential of Au/TiO2 catalysts in aerobic oxidation of alcohols in the unique multiphase reaction system with water as promoting solvent. 相似文献
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44.
由工艺实验得出了木糖醇悬浮液的过滤方程和干燥曲线 ,并对其特性进行了讨论。在此基础上 ,提出了木糖醇悬浮液过滤与干燥的工艺条件 ,这些结果可作为新工艺设计和老工艺改造的依据。 相似文献
45.
Long-term behavior of oil-based varnishes and paints I. Spectroscopic analysis of curing drying oils
Jacky Mallégol Jean-Luc Gardette Jacques Lemaire 《Journal of the American Oil Chemists' Society》1999,76(8):967-976
The curing of drying oils at 60°C has been investigated by Fourier transform infrared spectroscopy and Fourier transform Raman
analysis of linseed oil and poppyseed oil. In the first step, hydroperoxides are formed (broad vibration band centered around
3425 cm−1) with concomitant conjugation and cis-trans isomerization of the double bonds (disappearance of cis bands at 3011 and 716 cm−1, appearance of trans conjugated and trans nonconjugated bands at 987 and 970 cm−1). The subsequent decomposition of hydroperoxides in the presence of oxygen leads to the formation of alcohols (nitrite band
at 779 cm−1 after nitrogen monoxide treatment), aldehydes (bands at 2810 and 2717 cm−1 in gas phase), ketones (saturated and unsaturated at 1720 and 1698 cm−1, respectively), carboxylic acids (saturated and unsaturated acid fluorides identified at 1843 and 1810 cm−1 after SF4 treatment), and peresters or γ-lactones (near 1770 cm−1). A rapid decrease in the double-bond concentration is recorded when curing continues, and the formation of epoxides, characterized
by a vibration band at 885 cm−1, is observed. Thermolysis experiments have suggested the proposal of a reaction of addition of peroxyl radicals on the conjugated
double bonds as a probable mechanism. This mechanism explains both the rapid disappearance of conjugated double bonds and
the formation of epoxides as intermediate products observed in the initial step of curing. 相似文献
46.
Sang-Wook Park Hyun-Bum Cho Dong-Soo Suh Chan-Woo Kim 《Korean Journal of Chemical Engineering》1999,16(2):221-228
Experiments were performed on the esterification of lauric acid with isopropyl alcohol by tricaprylylmethylammonium chloride in a stirred vessel with a flat liquid-liquid interface. The observed initial rate of reaction was used to analyze the reaction mechanism combined with the catalyst, and to evaluate the several kinds of reaction rate constant, from which equilibrium constants were expressed as a function of reaction temperature. The analysis of reaction kinetics indicated that the reaction was between a very slow and slow reaction regime. 相似文献
47.
合成了一种具有表活性特征的多效高分子聚合物,进而研制开发出一种新型的可回收压裂液体系,通过实时调整主剂使用浓度,实现了降阻水、低黏液及携砂液的功能。室内实验结果表明,该压裂液体系具有低摩阻、可回收、易返排,易破胶,携砂性能好,且可以满足连续混配、污水配液等优点。截至2014年年底已成功应用于苏里格气田工厂化作业78口直井,取得了较好的改造效果。该研究解决了长庆气田"工厂化"作业返排液重复利用技术难题,有效缓解了环保压力,同时极大地节约了配液用水和化工料的用量。 相似文献
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49.
老龙口水利枢纽工程可使珲春河防洪标准由不足20年一遇提高到50年一遇洪水标准,保护下游人口60.83万人,保护耕地11.91万亩;每年可为城区供水2.828亿m3,为下游15.13万亩农田提供灌溉用水,老龙口水电站装机三台,总装机容量19.2MW,电站年发电量5199万kWh.因此老龙口水利枢纽工程的建设对加快珲春市,... 相似文献
50.