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Co-based catalysts were prepared by using dielectric-barrier discharge (DBD) plasma as an alternative method to conventional thermal calcination. The characterization results of N2-physisorption, temperature programmed reduction (TPR), transmission electron microscope (TEM), and X-ray diffraction (XRD) indicated that the catalysts prepared by DBD plasma had a higher specific surface area, lower reduction temperature, smaller particle size and higher cobalt dispersion as compared to calcined catalysts. The DBD plasma method can prevent the sintering and aggregation of active particles on the support due to the decreased treatment time (0.5 h) at lower temperature compared to the longer thermal calcination at higher temperature (at 500℃ for 5 h). As a result, the catalytic performance of the Fischer-Tropsch synthesis on DBD plasma treated Co/SiO2 catalyst showed an enhanced activity, C5+ selectivity and catalytic stability as compared to the conventional thermal calcined Co/SiO2 catalyst. 相似文献
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稀土类热稳定剂具有优异的热稳定功能,透明性好,无毒环保,与其它的助剂有广泛的协同作用。本文合成一种新型稀土热稳定剂原儿茶酸镧,并通过红外光谱分析,确定产物的结构特征。通过刚果红法对其在PVC中的热稳定性能进行研究,结果表明原儿茶酸镧显示出了较好的热稳定性,且热稳定时间随着原儿茶酸镧用量的增大而增大。其热稳定性低于硬脂酸钙,低于铅盐热稳定剂,略高于有机锡218等其它无毒热稳定剂,稳定时间为7.5min。当季戊四醇和原儿茶酸镧与按质量比为1∶2复合添加到PVC中,显示出较好的协同作用。 相似文献
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化学实验是化学研究以及教学中不可或缺的重要环节,在进行化学实验的过程中,会产生大量的实验室废水,这些废水中往往含有大量的有害物质,如果将这些废水直接排放到自然环境中,必然会对自然环境造成非常大的危害。因此,在完成化学实验后,就需要对产生的废水进行科学、有效的处理,消除废水中存在的有害物质,然后将处理后的清水排放到自然界或者对其进行重复利用,这样可以避免废水对环境的影响。 相似文献
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