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71.
A novel technology of removing H2S with cupric chloride solution was developed in this paper. Cupric as the form of CuS deposition, the CuS produced was then oxidized by excessive cupric ion in another reactor meanwhile cupric ion that has been consumed can be recovered by the oxidization of CuCl2- with oxygen in air,and the solution can be circulated. Moreover, the leaching kinetics of CuS by cupric ion was studied. The removal efficiency of H2S is close to 100%, and the required operating condition is mild. Compared with other wet oxidization methods, no raw material is consumed except O2 in air, the process has no secondary pollution and no problem of degradation and scale, and the absorbent is much stable and reliable. 相似文献
72.
稀土复合热稳定剂对聚氯乙烯性能影响研究 总被引:7,自引:0,他引:7
主要以有机锡热稳定剂为对比物,研究了稀土热稳定剂对聚氯乙烯(PVC)的热稳定性及其他性能的影响。稀土热稳定剂对PVC的力学性能、加工性能都有不同程度的提高,稀土热稳定剂的热稳定性能符合PVC的加工条件要求,并研究了抗冲改性剂ACR(丙烯酸酯共聚物)对体系的影响。 相似文献
73.
The structural changes and mechanical performance of virgin poly(vinyl chloride) (PVC) bottle (VB) compounds blended with postconsumer PVC bottles collected from a specified factory (RB‐F) and houses (RB‐H), were examined before and after UV irradiation at 313‐nm UV wavelength for different periods of time up to 28 days. The results indicated that, when exposed to UV light, the RB‐F/VB blends containing greater conjugated double bonds with higher yellowness index appeared to exhibit better mechanical performance than that of the RB‐H/VB blends. It was found that the amount of conjugated double bonds was not a linear function of the discoloration level of PVC compounds. Tensile strength of the VB compounds was not affected when incorporated with RB‐F recyclate, but progressively decreased with increasing RB‐H recyclate. An optimum concentration for RB recyclates to be added into the virgin compound was recommended for obtaining a maximum impact strength. Both tensile and impact strengths decreased with increasing UV exposure time, a severe degradation being obvious after a UV exposure time of 21 days. Hardness was not affected significantly by the addition of PVC recyclate, but increased with increasing UV exposure time. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 84–94, 2004 相似文献
74.
The pitting behaviour of type 321 stainless steel in sulfide-containing chloride aqueous environments was studied using cyclic potentiodynamic polarization. A well-established correlation between H2S and Na2S2O3 in the study of corrosion was applied, that is, H2S was simulated by Na2S2O3. The major factors affecting the pitting corrosion of type 321 stainless steel are the Cl- concentration, solution pH and temperature. The results clearly indicate that both Epit and E
pp decrease with increasing Cl- concentration and temperature, while I
pass is more sensitive to temperature variation. E
pit decreased with decreasing pH in the range 2 < pH < 7.5. The surface morphology and chemistry of the corroded type 321 stainless steel resulting from anodic polarization in 0.01 M S2O
3
2-
-containing Cl- solution were analysed by XRD, SEM and EPMA. A higher concentration of sulfur was found in the pits, and the dark surface film was mainly composed of FeS and -Fe2O3. The results describe the pitting behaviour of type 321 stainless steel in sulfide-containing Cl- aqueous environments. 相似文献
75.
简述不同相态类别,不同活性类别和不同结构类别的聚氯乙烯引发剂的一般特点,对国内聚氯乙类引发剂的开发与应用有参考价值。 相似文献
76.
77.
氯化聚氯乙烯的特性、制备及应用 总被引:1,自引:0,他引:1
氯化聚氯乙烯作为聚氯乙烯的化学改性产物,具有的特殊性能使其发展前景较为广阔。主要叙述了氯化聚氯乙烯所具备的优良性能、制备技术及应用领域。 相似文献
78.
79.
2-羟丙基三甲基氯化铵壳聚糖的制备及其表征 总被引:18,自引:0,他引:18
以脱乙酰度为90%的壳聚糖(CTS)为原料,异丙醇为溶剂,w(NaOH)=40 0%的水溶液为催化剂,3 氯 2 羟丙基三甲基氯化铵(CTA)为改性剂,在m(NaOH)∶m(CTS)=1 0∶1 0,m(CTA)∶m(CTS)=4 0∶1 0,反应温度65 0℃下制备了2 羟丙基三甲基氯化铵壳聚糖(HTCC)。实验结果表明,在反应时间达到或超过9 0h时,得到的HTCC产品的接枝度超过90 0%,在pH=6 7~7 0的水中可完全溶解形成w(HTCC)=3 0%的溶液。IR和1HNMR的结果表明,接枝反应主要发生在CTS的氨基上。 相似文献
80.
A new synthesis of poly(amido-amine)s from bis (secondary amine)s and acryloyl chloride has been studied, leading to polymers in which the amido- and amino-groups are randomly arranged along the macromolecular chain. A poly(amido-amine) based on piperazine, chosen as the mother compound, has been fully characterized by 13C n.m.r. as well as by identification and quantitative evaluation of its hydrolysis products. 相似文献