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氧化条件下NOx催化的甲烷均相部分氧化
甲烷氧化 NOx催化 均相催化 催化燃烧
2009/12/8
考察了没有固体催化剂时NOx对甲烷气相氧化的促进作用.实验结果表明，即使在强氧化条件下（O2/CH4=5），NOx对甲烷部分氧化制一氧化碳仍然有明显的催化活性.在CH4-O2体系中加入0.005％～0.2％的NO后，反应温度可降低200-300 ℃.在反应产物中还可观察到甲醛和乙烯，通过改变反应条件可以控制它们的相对浓度.
采用溶胶-凝胶法合成了一系列铁锰复合氧化物催化剂, 利用X射线衍射(XRD)对催化剂的活性相态进行研究, 并考察了铁锰摩尔比及焙烧温度对催化性能的影响. 结果表明, 该催化剂体系在低温(80-220 ℃)下选择性催化氨还原NOx反应中显示出优异的活性. 其中Fe(0.4)-MnOx(500)(即摩尔比n(Fe)/(n(Fe)+n(Mn))=0.4, 焙烧温度500 ℃)催化剂具有最佳低温催化活性,...
Cu对Pt/Cu-Mg-Al-O催化剂上NOx储存性能的影响
氮氧化物 水滑石 NOx储存 贫燃 Pt/Cu-Mg-Al-O
2009/11/26
固定二价与三价阳离子摩尔比为3∶1,采用共沉淀法合成系列Cu-Mg-Al水滑石,经500 ℃焙烧制成复合氧化物Cu-Mg-Al-O（wCuO(％)分别为0、5、10、20,简称w-CMAO, w=0、5、10、20）.通过浸渍法制备Pt/Cu-Mg-Al-O负载型复合氧化物催化剂.XRD结果表明Cu在催化剂及其前驱体中高度分散.采用等温NOx储存实验研究催化剂对NOx的储存性能, NOx-TPD法...
采用程序升温反应(TPR)技术,研究了等离子体辅助同时催化去除富氧柴油机尾气中NOx和碳烟(soot)的反应特性.研究结果表明,等离子体提高了同时去除NOx-soot的催化反应活性,降低了碳烟的燃烧温度,使碳烟起燃温度从300 ℃降到280 ℃,燃尽温度从425 ℃降到380 ℃;同时,等离子体辅助提高了NOx转化为N2的效率,使催化选择性从1.12％提高到1.53％.本文还分别研究了在NO和...
NOx production by lightning in Hector: first airborne measurements during SCOUT-O3/ACTIVE
lightning Hector SCOUT-O3/ACTIVE
2009/11/19
During the SCOUT-O3/ACTIVE field phase in November–December 2005, airborne in situ measurements were performed inside and in the vicinity of thunderstorms over northern Australia with several research...
旋涡式低NOX煤粉燃烧器燃烧特性的数值模拟
低NOx排放 煤粉燃烧器 旋涡
2009/11/4
在冷态实验和数值研究的基础上，采用STAR-CD软件对旋涡式低NOx煤粉燃烧器进行了热态模拟，分别得出了燃烧器内还原区和燃尽区的燃烧特性. 还原区流场呈涡旋状，颗粒处在高速旋转、燃烧、破碎的状态，其内严重缺氧，温度较低且分布均匀. 燃尽区内氧气浓度相对较高，温度较高，有利于颗粒的燃尽. 对于0.5 mm以下颗粒，本燃烧器能够稳定地燃烧，并得到较低的氮氧化物排放. 对燃烧器优化设计的计算结果表明，将...
The impact of resolution on ship plume simulations with NOx chemistry
resolution ship plume simulations NOx chemistry
2009/10/13
A high resolution chemical transport model of the marine boundary layer is designed in order to investigate the detailed chemical evolution of a ship plume in a tropical location. To estimate systemat...
Lightning-produced NOx during the Northern Australian monsoon; results from the ACTIVE campaign
Lightning-produced NOx Northern Australian monsoon ACTIVE campaign
2009/10/9
Measurements of nitrogen oxides onboard a high altitude aircraft were carried out for the first time during the Northern Australian monsoon in the framework of the Aerosol and Chemical Transport in Tr...
(Ag/Al2O3+Cu/Ce(x)/Al2O3)组合催化剂催化乙醇选择性还原NOx及其副产物的消除
银 化铝 氧化催化剂 氧化铜 氧化铈 氮氧化物 乙醇 选择性催化还原 一氧化碳 未燃碳氢化合物
2009/9/15
制备了Cu/Ce(x)/Al2O3(x为Ce与Al的摩尔比)系列氧化催化剂,并考察了(Ag/Al2O3+Cu/Ce(x)/Al2O3)组合体系催化乙醇还原NOx以及氧化去除反应副产物(CO和未完全燃烧的碳氢化合物)的活性. 在200～350 ℃温度区间,组合催化剂具有与Ag/Al2O3相似的NOx去除效率. 随着Ce/Al比增加,氧化催化剂去除CO的活性逐渐提高. Cu/CeO2催化剂具有最好的氧...
考察了 In/SO42–/TiO2 (In/STi)催化剂上甲烷选择性催化还原(CH4-SCR)NOx 的活性, 分析了硫酸化对催化活性的促进作用. 结果表明, 硫酸化影响了 In 在催化剂表面的存在形态和 CH4 的活化产物, 从而提高了催化剂活性. 吡啶红外光谱分析表明, 硫酸化后的 STi 载体可提供足够强度的 B 酸位, 有利于活性中心 InO+物种的形成. 原位红外光谱分析表明, ...
采用柠檬酸法合成了一系列铬锰复合氧化物催化剂,利用X射线衍射及X射线光电子能谱研究了催化剂活性相态,并考察了铬锰摩尔比对反应活性的影响. 结果表明,该体系在有氧条件下氨低温选择性催化还原氮氧化物反应中显示出优异的活性,其中Cr(0.4)-MnOx催化剂具有最佳低温催化活性,在空速30000h-1和120 ℃条件下, NOx转化率达98.5%, N2选择性达100%. 在MnOx中添加Cr后形成了C...
The formation of secondary organic aerosol from the isoprene + OH reaction in the absence of NOx
secondary organic aerosol isoprene + OH reaction absence of NOx
2009/9/14
The reaction of isoprene (C5H8) with hydroxyl radicals has been studied in the absence of nitrogen oxides (NOx) to determine physical and chemical characteristics of the secondary organic aerosol form...
Observations of NOx, $§igma$PNs, $§igma$ANs, and HNO3 at a Rural Site in the California Sierra Nevada Mountains: summertime diurnal cycles
NOx HNO3 California Sierra Nevada Mountains summertime diurnal cycles
2009/7/23
Observations of NO, NO2, total peroxy nitrates (ΣPNs), total alkyl nitrates (ΣANs), HNO3, CO, O3, and meteorological parameters were obtained from October 2000 through February 2002 at 1315 m a.s.l., ...
Summertime impact of convective transport and lightning NOx production over North America: modeling dependence on meteorological simulations
convective transport lightning NOx production North America meteorological simulations
2009/7/15
Global-scale chemical transport model simulations indicate lightning NOx dominates upper tropospheric O3 production above Eastern North America during summertime but vary in their estimates. To improv...
Energetic particle precipitation in ECHAM5/MESSy1 – Part 1: Downward transport of upper atmospheric NOx produced by low energy electrons
ECHAM5/MESSy1 upper atmospheric NOx low energy electrons
2009/5/6
The atmospheric chemistry general circulation model ECHAM5/MESSy1 has been extended by processes that parameterise particle precipitation. Several types of particle precipitation that directly affect ...