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81.
A novel chelating resin containing sulfoxide and diethylene glycol, poly{4‐vinylbenzyl‐[2‐2‐(hydroxyethyl)ethoxyl]sulfoxide} (PVESO) was synthesized using chloromethylated polystyrene (PS‐Cl) as material. Its structure was characterized by elemental analysis, infrared spectra, and scanning electron microscopy (SEM). The adsorption capacities of the resin for Hg2+, Ag+, Cu2+, Zn2+, and Pb2+ at various pH values were determined. The maximum adsorption capacities for Hg2+ and Ag+ were 1.56 and 0.75 mmol g?1 respectively. The resin had high selectivity for Hg2+ and Ag+ over the pH range 1.0–7.0. The adsorption capacities for Hg2+ and Ag+ under competitive condition were also determined by batch experiment method. In addition, the adsorption kinetics of the resin towards Hg2+ at different temperatures was also investigated. The results showed that the adsorption rate was governed by film diffusion at 20°C and 25°C, by particle diffusion at 30°C and 35°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6054–6059, 2006  相似文献   
82.
Gas phase propylene epoxidation on gold catalysts has attracted wide attention from industry and academia due to its high selectivity. However, it suffers from low propylene conversion and rapid catalyst deactivation. Experiments showed that propylene conversion could be increased by raising H2, O2, or C3H6 concentration in the feed, but the feed compositions were within the explosion limit. It was also shown that the activity of the used catalyst could be fully recovered, but the regeneration temperature was 280 °C, much higher than that for reaction. Therefore a microchannel reactor was devised to suppress explosion and was constructed with Fecralloy, to raise the temperature rapidly for catalyst regeneration by electric heating. In two minutes the temperature of the reactor could be raised from 50 to 300 °C. Catalysts were coated on the alloy belt by dip coating, and the performance of the reactor was evaluated under different operating conditions. Results showed that in the microreactor the overall reaction rate was controlled mainly by the intrinsic reaction rate, and also influenced by film diffusion to a certain extent. The deactivated catalyst was regenerated in the microchannel reactor and the activity was fully recovered.  相似文献   
83.
硫醇自组装膜的电化学研究进展   总被引:1,自引:0,他引:1  
综述了在金电极上硫醇自组装膜的电化学表征方法,性质和应用,介绍了自组装膜上的电子传递机理,并进行了简要的展望。  相似文献   
84.
污泥中总磷测定方法的探讨   总被引:1,自引:0,他引:1  
污泥样品与氢氧化钠熔融,使污泥中含磷有机化合物全部转化为可溶性的正磷酸盐,然后测定污泥中的总磷含量.此方法方便易行,平行性好,准确度高,可作为测定污泥中总磷的标准方法.  相似文献   
85.
对A203型低温氨合成催化剂的使用进行总结,介绍了该催化剂的装填,升温还原情况及使用效果。  相似文献   
86.
农作物秸秆增强氟石膏复合材料的微观结构研究   总被引:1,自引:0,他引:1  
将玉米秸秆加入改性后的氟石膏中,研究改性剂、玉米秸秆对氟石膏复合材料结构性能的影响;并用苯丙乳液对玉米秸秆纤维进行表面处理,用以改善基体材料和增强材料的界面结合状况,由此显著提高制品性能。  相似文献   
87.
Dongsheng Tang  Lianfeng Sun  Weiya Zhou 《Carbon》2005,43(13):2812-2816
By investigating the morphologies and microstructures of the cathode deposits prepared by self-sustained arc discharge between graphite rods, we consider that there are two electron emission mechanisms occurring on the cathode: field emission and thermionic emission. The former occurs mainly on the edge of the growing surface, by which we can explain the formation of the outer hard shell of the cathode deposit; while the latter occurs mainly on the growing surface except for the edge area and it is the main cause for the growth of carbon nanotubes.  相似文献   
88.
A novel sol–gel method based on V2O5·nH2O hydro-gel was developed to synthesize nanocrystalline Li3V2(PO4)3/carbon composite material. In this route, V2O5·nH2O hydro-gel, NH4H2PO4, Li2CO3 and high-surface-area carbon were used as starting materials to prepare precursor, and the Li3V2(PO4)3/carbon was obtained by sintering precursor at 750 °C for 4 h in flowing argon. The sol–gel synthesis ensures homogeneity of the precursors and improved reactivity. The sample was characterized by XRD, SEM and TEM. X-ray diffraction results show Li3V2(PO4)3 sample is monoclinic structure with the space group of P21/n. The TEM image indicates that the Li3V2(PO4)3 particles modified by conductive carbon are about 70 nm in diameter. The Li3V2(PO4)3/carbon system showed that the discharge capacities in the first and 50th cycle are about 155.3 and 143.6 mAh/g, respectively, in the range of 3.0–4.8 V. The sol–gel method is fit for the preparation of Li3V2(PO4)3/carbon composite material which may offer some favorable properties for commercial application.  相似文献   
89.
本文合成了一系列不同相对分子质量的聚丙烯酸钠,应用于艺术瓷的坯体中,研究了聚丙烯酸钠对艺术瓷坯体强度、变形率的影响,并对聚丙烯酸钠增强机理进行了探讨。结果表明:聚丙烯酸钠可有效地提高艺术瓷坯体的成形强度,减少了坯体的变形率,当增强剂c加入的质量分数为0.6%时,坯体的干燥强度增加率达167.5%,坯体的变形率从50%降低到10%。  相似文献   
90.
国产核电厂蒸汽发生器下封头群孔接管区具有应力分布复杂、焊接施工条件差的特点。为考核其承受循环载荷的能力,设计制造了与实物相似的模拟试验装置,根据核电厂运行寿命期内的载荷特点,确定了模拟试验装置的试验载荷与试验循环数。循环加载试验的结果表明,蒸汽发生器下封头群孔接管区承受循环载荷的能力在寿命期内是符合要求的。  相似文献   
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