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1.
收集了2018年7月~2019年6月世界工程塑料和特种工程塑料工业的相关资料,介绍了2018~2019年世界工程塑料和特种工程塑料工业的发展情况,按工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯)和特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮、聚芳砜、聚邻苯二甲酰胺)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。 相似文献
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含H_2S井完井液对井下金属管串具有腐蚀性。采用锌基或铁基螯合物除硫剂及咪唑啉缓蚀剂可有效地防止这种腐蚀的发生。本文对H_2S的腐蚀、除硫剂和缓蚀剂产品及其对产层的损害作了介绍与探讨。 相似文献
4.
以水杨醛类Schiff碱为配体,与Co(NO_3)_2、Cu(NO_3)_2反应合成6种Salen(M)型配合物Ⅰ~Ⅵ。以1-己硫醇、二丁基硫醚和2-甲基噻吩为模型化合物配制模拟油体系,考察了配合物Ⅰ~Ⅵ的催化氧化脱硫性能,并分析了配合物结构与氧化脱硫性能的关系。结果表明,6种配合物在75 min时的总脱硫效果为Ⅵ>Ⅴ>Ⅳ>Ⅰ>Ⅲ>Ⅱ,Ⅵ的总脱硫率为31.9%。对1-己硫醇及二丁基硫醚脱除效果最佳的是Ⅴ,脱除率分别为74.2%和65.1%;对2-甲基噻吩脱除效果最好的是Ⅰ,脱除率为26.8%。构效关系研究表明,中心金属离子与O_2的配位能力越强,配体的共轭体系越大、电子云密度越高,配合物的脱硫性能越好;通过IR和离子色谱对单一硫化物模拟油体系氧化前后的产物进行分析发现,硫化物氧化后皆生成相应的砜类或亚砜类,且1-己硫醇和二丁基硫醚被进一步氧化生成SO_3~(2–)或SO_4~(2–)。 相似文献
5.
聚苯硫醚/聚砜共混物的动态黏弹行为及相容性研究 总被引:1,自引:0,他引:1
研究了聚苯硫醚/聚砜熔融共混物的的加工流变行为以及共混物在不同温度下的动态黏弹响应;并对其相容性作出判断。结果表明,聚苯硫醚的加入显著改善了共混物的流动性,使其可在较低温度下成型;熔融态共混体系的相容性较差,固态条件下的相分离程度及损耗因子峰值大小依赖于组成变化。 相似文献
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炼油厂碱水生化预处理研究 总被引:4,自引:0,他引:4
采用曝气生物滤池氧化工艺对炼油厂碱水进行预处理。研究了污水中的COD、硫化物、酚、油等污染物浓度、污水在生物滤池中的水力停留时间(HRT)、反冲洗等参数对处理效果的影响。实验结果表明,污水中的硫化物比酚更容易在滤池中被生物降解,当停留时间为10 h时,污水中的COD、硫化物、油和酚的平均去除率分别为73.4%、98.6%、90.1%和79.7%。 相似文献
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The removal of hydrogen sulfide (H2S) from simulated gas was carried out in a batch type fluidized-bed reactor using natural manganese ore (NMO), which consists
of several metal oxides (MnOx: 51.85%, FeOy: 3.86%, CaO: 0.11%). The H2S breakthrough curves were obtained by changing temperature, gas velocity, initial H2S concentration, and aspect ratio. Moreover, the effects of the particle size and the particle-mixing fraction on H2S removal were investigated in a binary system of different particle size. From this study, H2S removal efficiency increased with increasing temperature but decreased with increasing excess gas velocity. The breakthrough
time for H2S decreased as the gas velocity increased, which leads to reducing gas-solid contacting due to gas bypassing in a fluidized
bed reactor. Improvement of H2S removal efficiency in continuous process can be expected from the results of the binary particle system with different size
in a batch experiment. The NMO could be considered as a potential sorbent in H2S removal. 相似文献
8.
主要介绍了几种聚芳硫醚类高性能树脂(聚苯硫醚、聚芳硫醚砜、聚芳硫醚酮、聚芳硫醚酰亚胺以及聚芳硫醚腈)的性能、研究动向以及产业化情况;并对今后聚芳硫醚类树脂的研究、发展趋势进行了预测。 相似文献
9.
Slow displacement rate tensile tests were carried out in a saturated H2S solution to investigate the effect of hydrogen embrittlement on notched tensile strength (NTS) and fracture characteristics of two ultra-high strength steels (PH 13-8 Mo stainless steel and T-200 maraging steel). Hydrogen permeation properties were determined by an electrochemical permeation method. The results of permeation tests indicated that over-aged specimens showed a lower diffusivity/hydrogen flux and higher solubility than those solution-annealed. The great increase in reverted austenite (irreversible hydrogen traps) together with numerous precipitates at the expense of dislocations (reversible) in the over-aged specimen led to such a change in permeability. Ordinary tensile tests indicated that four tested specimens had roughly the same yield strength level. Hence, the hydrogen embrittlement susceptibility of the material could be related to their permeation properties. The uniform distribution of strong hydrogen traps in over-aged specimens instead of weak traps in the solution-annealed impeded the hydrogen transport toward the strained region, thus, the resistance to sulfide stress corrosion cracking was improved in over-aged specimens. 相似文献
10.
The characterization of an optical sensor membrane is described for simultaneous determination of sulfite and sulfide ions based on the immobilization of crystal violet on a triacetylcellulose membrane. The absorbance of the membranes decreased by increasing sulfite and sulfide concentration. The partial least squares (PLS-1) calibration model based on spectrophotometric measurement for simultaneous determination of sulfite and sulfide ions was applied. This method is based on the difference between the rate of the reaction of sulfide and sulfite with membranes in pH 7.0 buffer solution and at 25 °C. The experimental calibration matrix for partial least squares (PLS-1) calibration was designed with 18 samples. The cross-validation method was used for selecting the number of factors. The results showed that simultaneous determination could be performed in the range of 200–2000 μg mL−1 (2.5–25 mmol L−1) and 80–900 μg mL−1 (2.5–28.125 mmol L−1) for sulfite and sulfide, respectively. The sensor can readily be regenerated with water and the color is fully reversible. The sensor was successfully applied to the simultaneous determination of sulfide and sulfite in water samples. 相似文献