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11.
攀钢转炉炼钢用碳化硅提温的试验研究 总被引:1,自引:1,他引:0
低品位碳化硅是转炉炼钢的有效提高温剂。工业性试验结果表明,碳化硅加入8.0kg/t钢水提温40.3-70.3℃(平均48.4℃);渣中TFe降低1.3%;加提温剂有利于转炉内造渣脱硫和碱少炉渣对耐火砖的侵蚀。文中还给出了攀钢转炉半钢冶炼铸用钢不水时加与不加碳化硅的tλ,[C]λ区域。 相似文献
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A polymerizable photoredox system consisting of 4-methacryl oxbenzophenone (MABP) and N,N-dimethlaminoethyl methacrylate (DMAEMA) used for the photopolymerization of acrylonitrile (AN) was studied. It was found that the polymerization rate is proportional to the 0.93th power for the AN concentration, the 0.28th power for the MABP concentration, and the 0.25th power for the DMAEMA concentration. The overall activation energy of the polymerization obtained is 30.43 kJ/mol. The recorded ESR spectrum indicates that the excited-state MABP abstraets hydrogen mainly from the methyl group of the dimethylamino moiety. The comparison of the initiation ability of polymeric MABP or polymeric DMAEMA with their monomeric forms has also been done and the results indicate that in good solvents P (MABP) has a much higher initiation ability than that of monomeric MABP, but monomeric DMAEMA and P (DMAEMA) display almost the same initiation ability. In poor solvent, the initiation ability of P (MABP) is not so obviously higher than that in good solvents. The result of UV analysis of P (AN) initiated by the MABP–DMAEMA system indicates that both MABP and DMAEMA not only initiate the photopolymerization of AN, but also enter into P (AN) polymer chains. © 1994 John Wiley & Sons, Inc. 相似文献
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CAPP系统中工艺卡片生成过程的研究 总被引:10,自引:1,他引:9
以AutoCAD2 0 0 0为开发平台、VC + + 6 0为开发环境、ObjectARX2 0 0 0为开发工具、SQLServer为后台数据库 ,通过编写writeText、fillGykztb、fillGykjtb等自定义函数 ,生成工艺卡片 ,并实现工序内容在工艺卡片中的分页显示等功能。 相似文献
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介绍了用自顶向下的结构化方法进行科研项目管理信息系统设计的过程。该系统的应用节省了大量人力、物力和财力,提高了企业科研项目管理水平。 相似文献
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Miniaturized Hexagonal Stepped-Impedance Resonators and Their Applications to Filters 总被引:1,自引:0,他引:1
Rui-Jie Mao Xiao-Hong Tang Ling Wang Guo-Hong Du 《Microwave Theory and Techniques》2008,56(2):440-448
Miniaturized hexagonal stepped-impedance resonators and their applications to bandpass filters are presented. Based on the odd- and even-mode equivalent circuits, the resonance characteristics of these resonators are investigated. A series of circuit configurations, including the third-order Chebyshev, trisection, and fifth-order cascaded trisection filters, are constructed by the proposed resonators. These filters are very compact and have good stopband responses. Measured results validate the analysis and theoretical prediction with good agreement. 相似文献
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In this work, microcrystalline cellulose (MCC) was activated with ultrasonic waves. The influences of ultrasonic treatment on the changes of supramolecular structures and morphology structure were studied by WAXS and SEM. The accessibility of the MCC was characterized by water retention value (WRV) and specific surficial area. The influence of ultrasonic treatment on the reactivity of MCC was investigated through the reaction of MCC being oxidized into 2,3‐diadehyde cellulose (DAC) by periodate sodium. The mechanism of the reactivity change of ultrasonically treated MCC was examined. The results showed that the degree of crystallinity of MCC decreased and the degree of polymerization showed little change after treatment with ultrasonic waves. The morphologial variation of the treated MCC was significant when compared with the untreated MCC, which contribute to the improvement of accessibility. The aldehyde content of DAC prepared from ultrasonically treated MCC was improved from 64.19 to 85.00%, indicating that the regioselective oxidation reactivity of MCC was significantly improved. The aldehyde content was found to first increase with time of ultrasonic treatment to a point, and then decrease as time progressed. In addition, the aldehyde content was found to increase with an increase in ultrasonic power. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献