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31.
从催化裂化柴油中分离高纯度2,6-二甲基萘 总被引:3,自引:0,他引:3
以大庆石油化工总厂炼油厂催化柴油为原料 ,通过精馏分离得到二甲基萘 (DMN)窄馏分 (2 5 8~ 2 70℃ ) ,经糠醛溶剂抽提 ,减压蒸馏后 ,在 -10~ -2 5℃冷冻 2~ 5h ,离心分离制得纯度约 80 %的粗 2 ,6 DMN ,再经无水乙醇在 -10~ -2 5℃重结晶 ,得到纯度大于等于 98%的 2 ,6 DMN。 相似文献
32.
吴正太 《精细石油化工进展》2007,8(6):42-46
采用中石化金陵分公司研究院研制的CI-50(Pd/丝光沸石)作C5/C6烷烃异构化催化剂.详细介绍了该催化剂的工业放大试验装置的工艺流程、首次开工过程中技术问题及处理方法. 相似文献
33.
Reports an error in "Does reward increase or decrease creativity" by Robert Eisenberger and Michael Selbst (Journal of Personality and Social Psychology, 1994[Jun], Vol 66[6], 1116-1127). In the aforementioned article, Figures 1 and 2 were interchanged. The figures appear with their correct captions in the erratum. (The following abstract of the original article appeared in record 1994-40652-001.) Two studies involving 504 school children investigated why behaviorists and cognitively oriented investigators have come to opposite conclusions about reward's effects on creativity. A monetary reward for a high degree of divergent thought in 1 task (word construction) increased children's subsequent originality in a different task (picture drawing). The same reward, made contingent on a low degree of divergent thought, reduced this generalized originality. These effects were eliminated by using a large reward and were restored by keeping the large reward out of the children's sight. The results suggest that reward training increases generalized creativity when (1) a high degree of divergent thought is required and (2) the reward is presented in not too salient a fashion. The findings are consistent with a 2-factor interpretation of rewarded creativity effects that incorporates learned industriousness and selective attention. [A correction concerning this article appears in Journal of Personality & Social Psychology, 1994(Jul), Vol 67(1), 125. Figures 1 and 2 were interchanged.] (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
本文研究了LF6铝合金的超塑性/扩散连接组合工艺,用变形和再结晶的方法细化晶粒,成功地进行了SPF/DB工艺试验,利用电子探针观察了扩散连接接头的界面微观区域,并从机理上分析了金属的超塑性/扩散连接两种工艺之间的内部联系及其金属学行为。 相似文献
35.
Quenching with gases rather than oil or other liquid media has the advantages of reducing the risks concerning health and environment, while simultaneously homogenizing the quenching results and minimizing distortion due to a wide range of possible process parameter variations and the pure convective heat transfer. In this contribution, a coupled solution for increasing homogenization of quenching results within high pressure gas quenching will be presented. In the first stage, an experimental test facility was set up for flow investigations and in the second stage a numerical simulation model was generated. The numerical and experimental results of the flow through the chamber were compared for several boundary conditions. Finally, after complete verification of the simulation, the model may be used to assist in parameter variation for optimization of homogeneous high pressure gas quenching. 相似文献
36.
Polymer blends based on polyolefins are of a great interest owing to their broad spectrum of properties and practical applications. However, because of poor compatibilities of components, most of these systems generally exhibit high interfacial tension, a low degree of dispersion and poor mechanical properties. It is generally accepted that polypropylene (PP) and nylon 6 (N6) are not compatible and that their blending results in poor materials. The compatibility can be improved by the addition of a compatibilizer, and in this study PP was functionalized by maleic anhydride (MAH) in the presence of an optimized amount of dicumyl peroxide (DCP). The reaction was carried out in the molten state using an internal mixer. Then, once the compatibilizer polypropylene‐graft‐maleic anhydride (PP‐g‐MAH) was prepared, it was added at various concentrations (2.5–10 wt%) to 30/70 glass fibre reinforced N6 (GFRN6) PP, and the mechanical properties were evaluated. It was found that the incorporation of the compatibilizer enhanced the tensile properties (tensile strength and modulus) as well as the Izod impact properties of the notched samples. This was attributed to better interfacial adhesion as evidenced by scanning electron microscopy (SEM). The optimum in these properties was achieved at a critical PP‐g‐MAH concentration. Copyright © 2005 Society of Chemical Industry 相似文献
37.
Lutgendorf Susan K.; Russell Daniel; Ullrich Philip; Harris Tamara B.; Wallace Robert 《Canadian Metallurgical Quarterly》2004,23(5):465
This study prospectively examined the relationship between religious attendance, interleukin-6 (IL-6) levels, and mortality rates in a community-based sample of 557 older adults. Attending religious services more than once weekly was a significant predictor of lower subsequent 12-year mortality and elevated IL-6 levels (> 3.19 pg/mL), with a mortality ratio of .32 (95% confidence interval [CI] = 0.15,0.72; p 相似文献
38.
Fault-based side channel cryptanalysis is very effective against symmetric and asymmetric encryption algorithms. Although straightforward hardware and time redundancy based concurrent error detection (CED) architectures can be used to thwart such attacks, they entail significant overhead (either area or performance). In this paper we investigate two systematic approaches to low-cost, low-latency CED for symmetric encryption algorithm RC6. The proposed techniques have been validated on FPGA implementations of RC6, one of the advanced encryption standard finalists. 相似文献
39.
系统介绍了舞钢开发的针状铁素体型X70宽厚板的设计思路、工艺特点和实物水平;采用电炉 炉外精炼 连铸 TMCP工艺生产的X70宽厚板满足西气东输专用技术条件的要求,并批量应用在西气东输主干线工程中。 相似文献
40.