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孔隙结构和表面官能团是影响椰壳炭吸附量的重要因素。利用硝酸氧化、高温处理和微波处理三种方法对椰壳炭进行了改性和表征并研究其对酚类的吸附特性。结果表明,经硝酸氧化改性后椰壳炭表面酸性含氧基团增加240%,但孔隙结构被破坏,比表面积下降11%,孔容增加25%,对硝基苯酚吸附量下降41%;继续对其进行高温改性和微波改性,其比表面积和吸附量增加,但同时表面酸性含氧基团下降83%和38%。寻找适合的改性处理工艺条件,以最小的孔隙破坏为代价,增加表面酸性官能团,是提高椰壳炭对酚类物质吸附量的有效途径。 相似文献
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采用微波水热法制备了CdS/rGO纳米复合光催化剂,通过XRD、FTIR、XPS、SEM、TEM对其结构和形貌进行了表征,结合UV-Vis和密度泛函(DFT)计算对异质界面的电荷转移机制进行了研究。结果表明所得复合材料中CdS分散性好、显示出较高的可见光催化活性和光稳定性。当rGO含量为0.5 mg/mL时复合材料的光催化性能最佳,可见光照射120 min后亚甲基蓝(MB)的光降解率达到94.40%,且五次循环实验光催化效果接近。界面相互作用、差分电荷密度、平均静电势等计算结果表明CdS与rGO通过范德华弱相互作用形成稳定异质界面,电荷由CdS向rGO转移,电子和空穴在两相界面实现了有效分离,因而材料的光催化性能得到增强。 相似文献
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Inductive energy storage systems (IES)require opening switches which are technically much more difficult to realize than closing switches. Institute of Advanced Technology ( IAT ) puts forward a meat grinder with an inductive pulse power topology called slow transfer of energy through capacitive hybrid (STRETCH). In this topology, an integrated gate-commutated thyristor (IGCT) is capable of breaking the charging currents on the order of 4 kA, and it may encounter difficulties in expanding to higher energy systems. German-French Institute of Saint Louis (ISL) has developed a high-power opening switch based on standard high-power thyristors by using their so-called inverse current commutation with semiconductor devices (ICCOS) countercurrent commutation principle. Two topologies of the STRETCH meat grinder with ICCOS are analyzed. And they are compared based on the voltage across the main switch, the current multiplication factor and other aspects by u- sing Matlab simulations. The advantages and disadvantages of the two topologies are shown through the comparisons. Therefore a more suitable topology can be chosen for realistic applications accord- ing to their performances. 相似文献
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采用电沉积法制备铝基MnO2电极,通过Tafel曲线、阳极极化曲线考察了镀液组成、施镀时间、施镀温度、电流密度对电极催化活性和耐蚀性的影响。考察了温度对镀层形貌的影响,最优条件下制备的MnO2电极分别在120℃、250℃、320℃和400℃条件下焙烧4h,结果表明,在120℃和250℃焙烧所得MnO2的结晶程度比不焙烧时增大了20%,而320℃和400℃焙烧所得MnO2的结晶程度比不焙烧时略有增加;物相和晶型都没有发生明显变化。因此得出制备铝基MnO2电极的最佳镀液组成和工艺条件为:MnSO4.H2O 150g/L,H2SO450g/L,温度80℃,电流密度3mA/cm2,施镀时间75min,120℃焙烧4h。所得电极催化活性较好,耐蚀性较强。经XRD表征主要晶型为γ-MnO2,SEM表征为球状堆积物。 相似文献
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