机械化学法合成聚羧酸减水剂的表征与性能研究

采用机械化学法和水溶液聚合法合成一系列聚羧酸高性能减水剂(PCE),采用凝胶渗透色谱(GPC)和傅里叶变换红外光谱(FT-IR)对其进行结构表征,并对其固含量和水泥净浆流动度进行测试。结果表明:机械化学法与水溶液聚合法制备的PCE分子量主峰出峰范围和官能团特征吸收峰一致,说明两种方法合成的PCE具有相似的分子结构。机械化学法反应30 min单体转化率可达到50.52%;合成的PCE固含量均在90%以上,远高于水溶液聚合法的39.16%;在掺量为0.30%,水灰比为0.29时,净浆流动度可达到260 mm以上,具有良好的减水分散作用。

Ag/AgCl/质子化g-C_3N_4纳米复合材料的制备及其光催化性能的研究

采用沉积-沉淀法制备Ag/AgCl/质子化g-C_3N_4(Ag/AgCl/p-g-C_3N_4)纳米复合材料,通过XRD、TEM、XPS、UV-Vis和PL对样品的结构、形貌和光学性能进行了表征。UV-Vis和PL分析表明,相比于纯gC_3N_4,p-g-C_3N_4和Ag/AgCl/p-g-C_3N_4纳米复合材料对可见光的响应能力和光生载流子的分离效率明显增强。通过可见光下降解甲基橙(MO)、盐酸四环素(TC)和环丙沙星(CIP)溶液评价样品的光催化性能。经优化后的Ag/AgCl/p-g-C_3N_4纳米复合材料在可见光照射60min后对MO的降解率达到90.4%,照射120 min后对TC和CIP的降解率分别为92.4%和76.1%。此外,Ag/AgCl/p-g-C_3N_4纳米复合材料具有良好的光催化稳定性。Ag/AgCl/p-g-C_3N_4纳米复合材料增强的光催化性能归因于Ag纳米颗粒的SPR效应以及Ag、AgCl和p-gC_3N_4之间的协同效应。

Fabrication, characterization and electrochemical properties of porous palladium bulk samples with high porosity and hierarchical pore structure

In the present study,porous bulk palladium samples were prepared by sodium chloride salt powder spacer incorporation and removal combined with dealloying.The obtained porous Pd bulks were characterized by X‐ray diffraction,field‐emission scanning electron microscopy and N2adsorption isotherm measurements.The prepared porous Pd bulk samples showed a hierarchical pore structure,a high porosity of^88%,a high surface area of^54m2/g,and a compression strength of^0.5MPa.Electrochemical measurements were performed to evaluate the electrocatalytic properties of the porous Pd bulk samples,revealing their effectiveness for ethanol oxidation.