In this paper, zirconium and cerium modified alumina were prepared by homogeneous precipitation with urea, and denoted as AlZC and AlZC-l with specific surface area of 200?m 2/g and 86?m 2/g, respectively. The catalyt...In this paper, zirconium and cerium modified alumina were prepared by homogeneous precipitation with urea, and denoted as AlZC and AlZC-l with specific surface area of 200?m 2/g and 86?m 2/g, respectively. The catalytic oxidation of methane on Co, Mn, Fe and Ni transition metal supported on the modified alumina supports was then investigated. The highest catalytic activity was found on the Co supported catalyst, and methane conversions on these catalysts decreased in the order Co>Mn>Fe>Ni. On the other hand, 15% Co/AlZC showed higher activity than 2% or 5% Co/AlZC at the low temperature region; While the former catalyst is inferior to the latter one at the high temperature region. The similar result was observed on the supported Mn catalysts investigated. Addition of Mn to 10% or 15%Co/AlZC at?molar ratio of Mn∶Co=1∶1 would promote the methane conversion as well as the water vapor resistance ability particularly at the low temperature region. Further studies on such a promoting effect are believed to be helpful to develop a new catalyst with a still higher methane oxidation activity.展开更多
Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of...Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of nerve agents are usually present at low concentration levels and mixed with a large amount of interferents.In this paper,six different kinds of solid-phase bulk sorbents were respectively investigated to improve the SPE efficiency for nerve agents degradation products from stimulant water samples,in which a large amount of background interferents were spiked.Results showed that the strong anion-exchange sorbent could selectively extract the spiking six target compounds from the matrices and showed a high recovery.展开更多
文摘In this paper, zirconium and cerium modified alumina were prepared by homogeneous precipitation with urea, and denoted as AlZC and AlZC-l with specific surface area of 200?m 2/g and 86?m 2/g, respectively. The catalytic oxidation of methane on Co, Mn, Fe and Ni transition metal supported on the modified alumina supports was then investigated. The highest catalytic activity was found on the Co supported catalyst, and methane conversions on these catalysts decreased in the order Co>Mn>Fe>Ni. On the other hand, 15% Co/AlZC showed higher activity than 2% or 5% Co/AlZC at the low temperature region; While the former catalyst is inferior to the latter one at the high temperature region. The similar result was observed on the supported Mn catalysts investigated. Addition of Mn to 10% or 15%Co/AlZC at?molar ratio of Mn∶Co=1∶1 would promote the methane conversion as well as the water vapor resistance ability particularly at the low temperature region. Further studies on such a promoting effect are believed to be helpful to develop a new catalyst with a still higher methane oxidation activity.
文摘Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of nerve agents are usually present at low concentration levels and mixed with a large amount of interferents.In this paper,six different kinds of solid-phase bulk sorbents were respectively investigated to improve the SPE efficiency for nerve agents degradation products from stimulant water samples,in which a large amount of background interferents were spiked.Results showed that the strong anion-exchange sorbent could selectively extract the spiking six target compounds from the matrices and showed a high recovery.
