摘要：Nanocatalysts consisting of three‐dimensionally ordered macroporous(3DOM)TiO2‐supported ultrafine Pd nanoparticles(Pd/3DOM‐TiO2‐GBMR)were readily fabricated by gas bubbling‐assisted membrane reduction(GBMR)*** catalysts had a well‐defined and highly ordered macroporous nanostructure with an average pore size of 280 *** addition,ultrafine hemispherical Pd nanoparticles(NPs)with a mean particle size of 1.1 nm were found to be well dispersed over the surface of the 3DOM‐TiO2 support and deposited on the inner walls of the *** nanostructure of the 3DOM‐TiO2 support ensured efficient contact between soot particles and the *** large interface area between the ultrafine Pd NPs and the TiO2 also increased the density of sites for O2 activation as a result of the strong metal(Pd)‐support(TiO2)interaction(SMSI).A Pd/3DOM‐TiO2‐GBMR catalyst with ultrafine Pd NPs(1.1 nm)exhibited higher catalytic activity during diesel soot combustion compared with that obtained from a specimen having relatively large Pd NPs(5.0 nm).The T10,T50 and T90 values obtained from the former were 295,370 and 415°*** the activity and nanostructure of the Pd/3DOM‐TiO2‐GBMR catalyst were stable over five replicate soot oxidation *** results suggest that nanocatalysts having a 3DOM structure together with ultrafine Pd NPs can decrease the amount of Pd required,and that this approach has potential practical applications in the catalytic combustion of diesel soot particles.

摘要：A series of catalysts consisting of three‐dimensionally ordered macroporous(3DOM)x‐CeO2/Al2O3‐supported Au nanoparticles(x=2,10,20,and40wt%)were successfully synthesized using a reduction‐deposition *** catalysts were characterized using scanning electron microscopy,the Brunauer‐Emmett‐Teller method,X‐ray diffraction,transmission electron microscopy,ultraviolet‐visible spectroscopy,and temperature‐programmed reduction by *** nanoparticles of mean particle size5nm were well dispersed and supported on the inner walls of uniform ***3DOM structure improved the contact efficiency between soot and the *** Al‐Ce‐O solid solution was formed in the multilayer support,i.e.,x‐CeO2/Al2O3,by the incorporation of Al3+ions into the CeO2lattice,which resulted in the creation of extrinsic oxygen *** interactions between the metal(Au)and the support(Ce)increased the amount of active oxygen species,and this promoted soot *** catalytic performance in soot combustion was evaluated using a temperature‐programmed oxidation *** presence of CeO2nanolayers in the3DOM Au/x‐CeO2/Al2O3catalysts clearly improved the catalytic activities in soot *** the prepared catalysts,3DOM Au/20%CeO2/Al2O3showed high catalytic activity and stability in diesel soot oxidation.

摘要：Au/3DOM（three-dimensionally ordered macroporous） Al2O3 and Au/CeO2/3DOM Al2O3 were prepared using a reduction-deposition method and characterized using scanning electron microscopy,N2 adsorption-desorption,X-ray diffraction,transmission electron microscopy,ultraviolet-visible spectroscopy,temperature-programmed hydrogen reduction,and X-ray photoelectron *** nanoparticles of similar sizes were well dispersed and supported on the inner walls of uniform *** norminal Au loading is 2%.Al-Ce-O solid solution in CeO2/3DOM Al2O3 catalysts can be formed due to the incorporation of Al^3＋ ions into the ceria lattice,which causes the creation of extrinsic oxygen *** extrinsic oxygen vacancies improved the oxygen-transport *** strong metal-support interactions between Au and CeO2 increased the amount of active oxygen on the Au nanoparticle surfaces,and this promoted soot *** activities of the Au-based catalysts were higher than those of the supports（Al2O3 or CeO2/3DOM Al2O3） at low ***/CeO2/3DOM Al2O3 had the highest catalytic activity for soot combustion,with T（10）,T（50）,and T（90） values of 273,364,and 412℃,respectively.

摘要：A series of K-doped Mn0.5Ce0.5Oδ （K-MCO） catalysts with three-dimensionally ordered macroporous （3DOM） structure and different K loadings were successfully synthesized using simple methods. These catalysts exhibited well-defined 3DOM nanostructure, which consisted of extensive interconnecting networks of spherical voids. The effects of the calcination temperature and calcination time on the morphological characteristics and crystalline forms of the catalysts were systematically studied. The catalysts showed high catalytic activity for the combustion of soot. 3DOM 20% K-MCO-4h catalyst, in particular, showed the highest catalytic activity of all of the catalysts studied （e.g., Ts0 = 331 ~C and Smco2 = 95.3%）. The occurrence of structural and synergistic effects among the K, Mn, and Ce atoms in the catalysts was favorable for enhancing their catalytic activity towards the combustion of diesel soot. Furthermore, the temperatures required for the complete combustion of the soot （〈400 ℃） were well within the exhaust temperature range （175-400 ℃）, which means that the accumulated soot can be removed under the conditions of the diesel exhaust gas. These catalysts could therefore be used in numerous practical applications because they are easy to synthesize, exhibit high catalytic activity, and can be made from low cost materials.

摘要：柴油机尾气中的炭烟颗粒(PM2.5)已经引起了严重的环境污染问题,作为控制柴油车尾气中炭烟颗粒使用最有效和最经济的技术手段—催化净化技术成为当前研究的热点,而开发高效的催化剂是催化净化技术中最活跃、最重要的因素.本文总结了近年来柴油炭烟燃烧催化剂的最新研究进展,重点介绍了本研究组近年来在柴油炭烟氧化催化剂的设计、制备和催化作用机理方面的研究结果和进展,主要包括:低共熔点催化剂、纳米催化剂、三维有序大孔催化剂及三维有序大孔氧化物担载贵金属催化剂的最新研究进展,并报道了上述催化剂对炭烟燃烧的反应机理.最后,总结性地提出了目前炭烟催化燃烧中存在的主要问题和发展方向.

摘要：新区作为当前城市空间发展的重要形式,是探索低碳城市空间布局与模式的前沿实践地.以国家级新区为研究样本,利用出行方式距离与能耗系数法计算样本新区的交通出行碳排放量,并转化为人均、地均和产均碳排放强度,综合反映城市新区的出行碳排放水平,据此择取低碳新区的较优样本;借助空间自相关和空间句法等方法构建关键指标,测度城市用地分布、道路网络、绿色开敞空间等要素,比较分析低碳新区样本的空间布局特征;在此基础上从各类建设用地疏解、绿色开敞空间有机、道路系统高效等层面提出城市新区总体空间低碳化优化策略,为西部“一带一路”沿线城镇新区绿色发展与规划建设提供经验借鉴.

摘要：现代主义城市是基于市场经济效率导向的,其空间主要呈现增量扩张的快速发展态势,但逐步失去了对"人的抚育"功能,尤其忽视老人、妇女、儿童以及身体残障人群的需求。基于儿童权利和儿童健康成长的需求,分析国外以"儿童友好型城市"建设为代表的空间实践,强调和保障儿童空间权利行使的主体地位,以儿童参与为重点,将儿童的根本需求纳入街区或城市的规划中,形成"儿童空间需求表达→设计与决策→物理空间呈现"的有效途径和制度保障体系。就国内而言,在儿童尚作为"权利客体"的境况下,深圳市尝试探寻由成人与儿童合作、从战略引领到项目落实的儿童友好型城市空间建设机制。