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排序方式: 共有1576条查询结果,搜索用时 15 毫秒
1.
用附聚法和降粘法浓缩SBR1502胶浆制取道路沥青改性用胶乳。结果表明:总固物质量分数可由(21±2)%上升到45%~50%。该胶乳与齐鲁石化公司炼油厂100号乙沥青混合,改性后的道路沥青具有良好的使用性能,可满足高等级路面沥青的技术要求。 相似文献
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指出施工监理是一项细致而又责任重大的工作。把握好污水处理厂关键工序的施工及检查,才能对污水处理工程进行有效地控制和管理,使之发挥最大的经济和社会效益。 相似文献
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丁苯胶乳改性道路沥青的推广应用 总被引:2,自引:0,他引:2
用丁苯胶乳对胜利100号沥青进行改性试验.发现随着胶乳掺量的增加.沥青的高温性能、粘结性能改善幅度也大。但综合考虑沥青生产成本等因素.认为:对丁苯胶乳改性胜利100号道路沥青.掺胶量控制在2%即可满足一般高等级道路工程的需要。文中还介绍了丁苯胶乳沥青近年来的推广使用情况并做了相应的技术经济分析和建议。 相似文献
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Characteristics of nitrogen and phosphorus removal in SBR and SBBR with different ammonium loading rates 总被引:2,自引:0,他引:2
Dong-Seog Kim No-Sung Jung Young-Seek Park 《Korean Journal of Chemical Engineering》2008,25(4):793-800
Laboratory scale experiments were conducted to study the deterioration of enhanced biological phosphorus removal (EBPR) due
to influent ammonium concentration, and to compare the performance of two types of sequencing batch reactor (SBR) systems,
a conventional SBR and sequencing batch biofilm reactor (SBBR). Both in SBR and SBBR, the total nitrogen removal efficiency
decreased from 100% to 53% and from 87.5% to 54.4%, respectively, with the increase of influent ammonium concentration from
20 mg/l to 80 mg/l. When the influent ammonium concentration was as low as 20 mg/l (C: N: P=200: 20: 15), denitrifying glycogen-accumulating organisms (DGAOs) were successfully grown and activated by using
glucose as a sole carbon source in a lab-scale anaerobic-oxic-anoxic (A2O) SBR. In the SBR, due to the effect of incomplete denitrification and pH drop, the nitrogen and phosphorus removal efficiency
decreased from 77% to 33.3% when the influent ammonium concentration increased from 20 mg/l to 80 mg/l. However, in the SBBR, simultaneous nitrification/denitrification (SND) occurred, and the nitrification rate in the aerobic
phase did not change remarkably in spite of the increase in influent ammonium concentration. Phosphorus removal was not affected
by the increase of influent ammonium concentration. 相似文献
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本文研究了γ-流基丙基三甲氧基硅烷(KH590)对白炭黑填充的SBR胶料的光接枝反应。通过接枝反应,提高了橡胶填料间界面粘合性,也提高了硫化胶的300%定伸模量,改善了撕裂强度、压缩永久变形及耐磨耗性等、此外,在NBR中也取得同样改性效果。尤其是,改善了耐碱性。但经照射后在室内放置会增加凝胶化,影响到加工性能. 相似文献
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Latexes of carboxylated styrene-butadiene rubber were prepared via batch emulsion copolymerization with different amounts of acrylic acid in the absence of emulsifier. The effect of acid monomer was investigated in the particle formation and growth. It was observed that the amount of acrylic acid strongly affected the particle formation. The number of particles and thus polymerization rate increased with increasing of the acid content. There was no significant difference in the polymerization rate per particle in all experiments. The results show that in this case particle growth process is less dependent on the acrylic acid amount in comparison with its influence on nucleation stage and then particle number. Several parameters such as polymerization rate and number of latex particle per unit volume of the aqueous phase were calculated. Attempt was made to evaluate the average number of growing chain per particle. Also average particle diameter of the above carboxylated SBR latexes was obtained through some calculations from the direct measurement of average particle diameter in the swollen state by light scattering technique for the first time. 相似文献
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