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以对甲苯磺酸为催化剂、甲苯为带水剂,以马来酸酐和十八醇为原料合成马来酸双十八酯。考察了原料配比、催化剂用量、带水剂用量和反应时间等因素对反应过程的影响,并测定了动力学数据。通过实验得到了反应工艺条件:n(十八醇):n(马来酸酐)=2.3:1,对甲苯磺酸用量为马来酸酐和十八醇总质量的0.5%,甲苯用量为马来酸酐和十八醇总质量的96%,反应温度≤130℃、反应时间为4.0h,在该条件下马来酸酐的转化率达到98.76%。合成马来酸单十八酯的反应为二级反应,速率方程中的指前因子为O.655152L/(mol·min),活化能为17.82kJ/mol。合成马来酸双十八酯的反应为二级反应,速率方程中的指前因子为1.53951×1011L/(mol·min),活化能为98.05kJ/mol。 相似文献
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基于流化催化裂化(FCC)轻汽油(初馏点-358 K)中所含烯烃组分的性质,将其划分为4个集总,采用管式滴流床反应器,在压力0.5-2 MPa、反应温度353-413 K、液体空速2.5-7.5 h-1的条件下,对烯烃在镍加氢催化剂上的加氢反应进行宏观动力学研究.实验结果显示:n-C4=,n-C5=,i-C5=,n-C... 相似文献
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Yu. A. Aminov A. V. Vershinin N. S. Es’kov O. V. Kostitsyn G. N. Rykovanov V. A. Sibilev M. A. Strizhenok 《Combustion, Explosion, and Shock Waves》1997,33(1):77-80
A one-stage detonation macrokinetics model of a low-sensitivity heterogeneous explosive is considered. Within the framework
of the model, we have managed to describe uniformly a wide class of experiments on initiation of aTATB-based plasticized explosive, including the initiation from the impact by a metallic plate and compact metallic fragments.
Institute of Technical Physics, Snezhinsk 456770. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 1, pp. 94–97, January–February,
1997. 相似文献
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Data on concretes soaked continuously in a 2.1 percent sodium sulfate solution and alternately soaked and dried served for predicting service life. Sixteen out of 19 concretes made with Type V and II cements showed life expectancies of less than 50 years. Concretes containing different pozzolans showed a spectrum of effects ranging from deleterious to highly beneficial. Only 6 out of 33 pozzolan concretes had life expectancies of less than 50 years. Fly ash, pumice, and two calcined products markedly improved sulfate resistance. Seven of 11 concretes having a life expectancy in excess of 100 years, some possibly up to 200 years, contained fly ash. Revision of present day specifications for sulfate resisting concrete is recommended. 相似文献
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Tomsk. Translated from Fizika Goreniya i Vzryva, Vol. 25, No. 6, pp. 104–112, November–December, 1989. 相似文献
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在较长时间(一般在24h以上)停窑以后,重新转窑投料时,熟料率值会有较大幅度变化,特别是LSF降低幅度较大,这种情况会随着投料量的增加而逐渐恢复正常。 相似文献
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聚酯(PET)瓶问题分析(一) 总被引:6,自引:1,他引:6
介绍热灌装PET瓶的收缩变形,测定瓶坯或瓶子树脂特性黏度的原因,影响PET树脂结晶性能的因素和树脂冷结晶峰温与制瓶工艺、瓶子质量之间的关系及如何提高树脂的冷结晶峰温。 相似文献
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阐述了SO2转化器蒸汽出口管道蒸汽减温器的作用以及蒸汽喷射阀发生腐蚀的原因,通过优化设计满足生产需要,降低投资成本。 相似文献
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T. Z. Fahidy 《Journal of Applied Electrochemistry》1990,20(6):901-906
A method of analysis of the stochastic behaviour of electrolyzers due to stationary random fluctuations in current and inlet electrolyte concentration is presented. The analysis is illustrated by means of a numerical example. 相似文献
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Propagation of pulsed perturbations in prestressed elastic and elastoviscoplastic media are simulated numerically. It is shown
that the occurrence of the initial stress state leads to the formation of wave structures that are absent in unloaded isotropic
media. A quasi-longitudinal wave that propagates in a prestressed elastoviscoplastic media is studied using the asymptotic
method.
Division of Explosion Geodynamics, Institute of Geophysics, Ukrainian National Academy of Sciences, Kiev 252054. Translated
from Fizika Goreniya i Vzryva Vol. 33, No. 2, pp. 124–132, March–April, 1997. 相似文献
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答:在陶瓷生产中,成形模型以及胎型的制作都会使用石膏粉。市场上有满足陶瓷注浆成形、滚压成形、冷压成形、母模胎型制作使用的各种石膏粉。 相似文献
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Summary The long-time crystallization of a set of polyethylenes, that have a variety of different molecular structures, has been studied
under storage conditions well removed from those where partial melting or relatively rapid crystallization takes place. For
high molecular weight linear polyethylenes, branched polyethylenes and ethylene copolymers a density increase of about 5%
is observed. However, analysis of the Raman internal modes indicates that the core crystallinity remains constant. It is found
that the density change reflects an increase in the partially ordered interfacial region at the expense of the disordered
liquid-like region. 相似文献
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