对拟建水泥厂项目进行环境风险评价,采用SLAB模型预测氨发生泄漏扩散到大气下风向的浓度分布。预测结果表明:发生泄漏后,对LC50(半致死浓度)最大影响距离为10.8 m,对IDLH(Immediately Dangerous to Life or Health,立即威胁生命和健康)...对拟建水泥厂项目进行环境风险评价,采用SLAB模型预测氨发生泄漏扩散到大气下风向的浓度分布。预测结果表明:发生泄漏后,对LC50(半致死浓度)最大影响距离为10.8 m,对IDLH(Immediately Dangerous to Life or Health,立即威胁生命和健康)能达到的最大影响距离为22.1 m,对居住区最高容许浓度最大影响距离为33.4 m,氨水泄漏的环境风险水平为可以接受。同时还提出了环境风险防范措施,水泥厂环境风险评价可为该项目建设决策提供技术依据。展开更多
On the basis of the QSCAT/NCEP blended wind data and simple ocean data assimilation （SODA）, the wind-induced near-inertial energy flux （NIEF） in the mixed layer of the South China Sea （SCS） is estimated by a sla...On the basis of the QSCAT/NCEP blended wind data and simple ocean data assimilation （SODA）, the wind-induced near-inertial energy flux （NIEF） in the mixed layer of the South China Sea （SCS） is estimated by a slab model, and the model results are verified by observational data near the Xisha Islands in the SCS. Then, the spatial and temporal variations of the NIEF in the SCS are analyzed. It is found that, the monthly mean NIEF exhibits obvious spatial and temporal variabilities, i.e., it is large west of Luzon Island all the year, east of the Indo-China Peninsula all the year except in spring, and in the northern SCS from May to Septem- ber. The large monthly mean NIEF in the first two zones may be affected by the large local wind stress curl whilst that in the last zone is probably due to the shallow mixed layer depth. Moreover, the monthly mean NIEF is relatively large in summer and autumn due to the passage of typhoons. The spatial mean NIEF in the mixed layer of the SCS is estimated to be about 1.25 mW/m2 and the total wind energy input from wind is approximately 4.4 GW. Furthermore, the interannual variability of the spatial monthly mean NIEF and the Nifio3.4 index are negatively correlated.展开更多
Periodic density functional theory（DFT） calculations are presented to describe the adsorption and decomposition of CH3OH on Ru（0001） surfaces with different coverages, including p（3 ×2）, p（2×2）, and ...Periodic density functional theory（DFT） calculations are presented to describe the adsorption and decomposition of CH3OH on Ru（0001） surfaces with different coverages, including p（3 ×2）, p（2×2）, and p（2× 1） unit cells, corresponding to monolayer（ML） coverages of 1/6, 1/4, and 1/2, respectively. The geometries and energies of all species involved in methanol dissociation were analyzed, and the initial decomposition reactions of methanol and the subsequent dehydrogenations reactions of CH3O and CH2OH were all computed at 1/2, 1/4, and 1/6 ML coverage on the Ru（0001） surface. The results show that coverage exerts some effects on the stable adsorption of CH30, CH2OH, and CH3, that is, the lower the coverage, the stronger the adsorption. Coverage also exerts effects on the initial decomposition of methanol. C-H bond breakage is favored at 1/2 ML, whereas C-H and O--H bond cleavages are preferred at 1/4 and 1/6 ML on the Ru（0001） surface, respectively. At 1/4 ML coverage on the Ru（0001） surface, the overall reaction mechanism can be written as 9CH3OH ,3CH30＋6CH2OH＋9H ,6CH20＋3CHOH＋18H , 7CHO＋COH＋CH＋OH＋26H → 8CO＋C＋O＋36H.展开更多
文摘对拟建水泥厂项目进行环境风险评价,采用SLAB模型预测氨发生泄漏扩散到大气下风向的浓度分布。预测结果表明:发生泄漏后,对LC50(半致死浓度)最大影响距离为10.8 m,对IDLH(Immediately Dangerous to Life or Health,立即威胁生命和健康)能达到的最大影响距离为22.1 m,对居住区最高容许浓度最大影响距离为33.4 m,氨水泄漏的环境风险水平为可以接受。同时还提出了环境风险防范措施,水泥厂环境风险评价可为该项目建设决策提供技术依据。
基金The Strategic Priority Research Program of the Chinese Academy of Sciences under contract No.XDA11020201the National Basic Research Program of China under contract No.2013CB956101+2 种基金the Knowledge Innovation Program of the Chinese Academy of Sciences under con-tract No.SQ201302the National Science Foundation Council Grant of China under contract Nos 41430964,41406023 and 41025019the Chinese Academy of Sciences/State Administration of Foreign Experts Affairs International Partnership Program for Creative Research Teams and General Research Fund of Hong Kong Research Grants Council under contract No.CUHK402912
文摘On the basis of the QSCAT/NCEP blended wind data and simple ocean data assimilation （SODA）, the wind-induced near-inertial energy flux （NIEF） in the mixed layer of the South China Sea （SCS） is estimated by a slab model, and the model results are verified by observational data near the Xisha Islands in the SCS. Then, the spatial and temporal variations of the NIEF in the SCS are analyzed. It is found that, the monthly mean NIEF exhibits obvious spatial and temporal variabilities, i.e., it is large west of Luzon Island all the year, east of the Indo-China Peninsula all the year except in spring, and in the northern SCS from May to Septem- ber. The large monthly mean NIEF in the first two zones may be affected by the large local wind stress curl whilst that in the last zone is probably due to the shallow mixed layer depth. Moreover, the monthly mean NIEF is relatively large in summer and autumn due to the passage of typhoons. The spatial mean NIEF in the mixed layer of the SCS is estimated to be about 1.25 mW/m2 and the total wind energy input from wind is approximately 4.4 GW. Furthermore, the interannual variability of the spatial monthly mean NIEF and the Nifio3.4 index are negatively correlated.
基金Supported by the Key Program of Natural Science of Tianjin, China（No. 13JCZDJC26800）, the National Natural Science Foundation of China（Nos.21503122, 21346002）, the Shanxi Province Science Foundation for Youths, China（No.2014021016-2）, the Scientific and Technological Programs in Shanxi Province, China（No.2015031017） and the Foundation of Key Laboratory of Advanced Energy Materials Chemistry of Ministry of Education of China.
文摘Periodic density functional theory（DFT） calculations are presented to describe the adsorption and decomposition of CH3OH on Ru（0001） surfaces with different coverages, including p（3 ×2）, p（2×2）, and p（2× 1） unit cells, corresponding to monolayer（ML） coverages of 1/6, 1/4, and 1/2, respectively. The geometries and energies of all species involved in methanol dissociation were analyzed, and the initial decomposition reactions of methanol and the subsequent dehydrogenations reactions of CH3O and CH2OH were all computed at 1/2, 1/4, and 1/6 ML coverage on the Ru（0001） surface. The results show that coverage exerts some effects on the stable adsorption of CH30, CH2OH, and CH3, that is, the lower the coverage, the stronger the adsorption. Coverage also exerts effects on the initial decomposition of methanol. C-H bond breakage is favored at 1/2 ML, whereas C-H and O--H bond cleavages are preferred at 1/4 and 1/6 ML on the Ru（0001） surface, respectively. At 1/4 ML coverage on the Ru（0001） surface, the overall reaction mechanism can be written as 9CH3OH ,3CH30＋6CH2OH＋9H ,6CH20＋3CHOH＋18H , 7CHO＋COH＋CH＋OH＋26H → 8CO＋C＋O＋36H.
