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排序方式: 共有3741条查询结果,搜索用时 15 毫秒
31.
Akio Takemura Yoshinori Shimizu Bunichiro Tomita Hiroshi Mizumachi 《The Journal of Adhesion》1992,37(1):161-172
Dynamic mechanical properties and adhesive strengths of power feed copolymer and random copolymer synthesized using styrene or methyl methacrylate and n-butyl acrylate were investigated. Although the two systems were synthesized from the same raw materials, power feed copolymer had a very broad transition compared with random copolymer. This fact was explained by the fact that the system synthesized through power feed method was an alloy of copolymers which are a continuous series from monomer A rich copolymers to monomer B rich copolymers. The dynamic mechanical behavior of film cast from solution was almost the same as that of emulsion film, which indicated more extensive application of power feed copolymer. In the P(nBA/St) system, power feed copolymer maintained its adhesive strengths over a wide temperature range compared with random copolymer. The absolute value, however, was not so high. This was due to the low cohesive strengths of the films. 相似文献
32.
33.
Hiroyuki Sumi Akio Takemura Mikio Kajiyama Yasunori Hatano Bunichiro Tomita Hiroshi Mizumachi 《The Journal of Adhesion》1992,38(3):173-184
Power feed copolymers were synthesized using styrene and n-butyl acrylate through non-uniform feeding emulsion polymerization. Poly(vinyl alcohol) (PVA) was used as a protective colloid, onto which vinyl monomers were grafted. Power feed copolymer had a very broad glass transition temperature compared with random copolymer, even if grafting and/or crosslinking were introduced to the system. This tendency was almost the same as the non-grafted power feed copolymer where only low molecular weight surfactant was used.
Adhesive joint strengths of power feed copolymers were evaluated compared with random copolymers. In the case of usual linear power feed copolymer, the adhesive joint strengths were not higher than those of random copolymer, which was considered to be due to the lower film strengths of the power feed copolymer. Power feed copolymer having grafting showed slightly higher adhesive joint strengths over a wide range of temperatures than random copolymer. When crosslinking was introduced to the system, power feed copolymer showed much higher adhesive joint strengths over a wide temperature range. 相似文献
Adhesive joint strengths of power feed copolymers were evaluated compared with random copolymers. In the case of usual linear power feed copolymer, the adhesive joint strengths were not higher than those of random copolymer, which was considered to be due to the lower film strengths of the power feed copolymer. Power feed copolymer having grafting showed slightly higher adhesive joint strengths over a wide range of temperatures than random copolymer. When crosslinking was introduced to the system, power feed copolymer showed much higher adhesive joint strengths over a wide temperature range. 相似文献
34.
黄磷尾气净化脱除磷化氢、硫化氢中试试验 总被引:7,自引:0,他引:7
采用自制的催化剂JC-4,设计出碱洗-催化氧化工艺对黄磷尾气进行深度净化处理。中试试验结果表明:常压、100℃、尾气流量为36~50 m3/h、氧气体积分数为1.2%~1.5%时,PH3的脱除率接近100%,出口质量浓度低于1.0 mg/m3;碱洗单元可以除去90%的H2S,经过催化氧化单元可以进一步脱除H2S,净化效率接近100%,出口质量浓度低于1.0 mg/m3;催化剂经100~200 h需要再生,400 h后需要活化,再生和活化处理后的催化剂性能良好。 相似文献
35.
变压吸附法处理硝酸尾气的研究 总被引:4,自引:1,他引:4
概述了硝酸尾气的处理方法,详述了变压吸附法处理硝酸尾气的原理,提出了处理尾气的工艺过程和工艺指标。 相似文献
36.
针对吸附系统内除湿剂硅胶频繁破碎现象进行优化。在找出硅胶破碎原因的基础上,通过吸附塔直径放大18.3%,引出部分尾气,使床层流速降低。在吸附塔进口管处,安装雾沫分离器;在硅胶前沿填充部分耐水硅胶以减少液态水的冲击。再生蒸汽加热管上加调节阀防止硅胶过分干燥。使A塔硅胶使用了540d,B塔硅胶使用了630d。 相似文献
37.
简要介绍了第四次中国石化总公司硫磺回收技术协作组年会上美意德3公司交流的技术,分别为:BOCSURE富氧硫回收工艺、高转化率Claus工艺、Clinsulf-DO工艺和Clinsulf-SDP工艺,反映了目前国外硫回收及尾气处理的部分进展状况。 相似文献
38.
双基地角在杂波单元内的连续变化导致宽波束双基地高频雷达的海杂波谱不同于窄波束.为了揭示这种差异,在G ill和W alsh窄波束双基地海面雷达散射截面积(RCS)基础上,提出了宽波束双基地海面RCS模型;结合高频地波雷达方程,得到宽波束双基地海杂波功率谱密度模型,通过仿真计算得到海杂波谱的具体形态.理论分析和仿真结果表明,在发射机附近以及基线附近的雷达探测区域,宽波束海杂波谱具有明显的展宽效应. 相似文献
39.
The corrosion of materials in combustion chamber of yellow phosphor tall gas was investrgated. The results reveal that the corrosion behavior is different for different materials under actual work conditions. 相似文献
40.
某厂采用一套设备稀释98%的浓硝酸,配制65%、40%和25%等浓度的稀硝酸,硝酸配稀时产生的尾气对环境造成污染,且危害工人健康。本系统采用带夹套的配酸贮槽来减少NOx的生成,同时用尿素溶液作还原剂吸收NOx;采用引射式吸收器作为吸收设备,使NOx反应生成的CO2和N2可直接排放,处理后的NOx含量在(100~300)×10-6之间,符合大气污染物综合排放标准(GB16297-1996)的要求,企业也实现了清洁生产。 相似文献