水生生态系统 ,特别是海洋无疑是大气 CO2 的一个巨大的汇。海洋对大气 CO2 的汇以及大气圈和海洋之间碳的变换量在很大程度上取决于混合层碳酸盐化学、水中溶解碳的平流传输、CO2 通过空气——海水界面的扩散、海洋生物生产和所产生的...水生生态系统 ,特别是海洋无疑是大气 CO2 的一个巨大的汇。海洋对大气 CO2 的汇以及大气圈和海洋之间碳的变换量在很大程度上取决于混合层碳酸盐化学、水中溶解碳的平流传输、CO2 通过空气——海水界面的扩散、海洋生物生产和所产生的有机碳化合物的沉降等 ,现在已建立和发展了多种海洋碳子模型以对 CO2 的汇进行估测。根据国内外研究资料 ,综述了水生生态系统碳循环过程及“生物泵”作用机制等方面的研究进展 ;介绍了两大类主要的海洋碳子模型 :厢式模型和普通环流模型 ,采用这些模型对海洋碳汇的估算约为 1 .2～ 2 .4 Gt C/a;分析了湖泊、河流等对大气 CO2 汇的特点及向海洋的转移 ,并对影响水体生态系统碳循环和大气 CO2展开更多
Decoloration of simulated wastewater containing dye reactive black K-BR by zero-valent iron was investigated. The results showed that decoloration efficiency increased with decreasing pH or initial dye concentration, ...Decoloration of simulated wastewater containing dye reactive black K-BR by zero-valent iron was investigated. The results showed that decoloration efficiency increased with decreasing pH or initial dye concentration, and increased with increasing iron loading. The reaction followed first-order kinetics initially but deviated from first-order behavior with increasing time. Considering the decrease of active surface area of zero-valent iron with time,decoloration kinetics was expressed as ln(c/c 0)=K[1-exp(-k dt)]/k d.It indicated that k d was independent of iron loading and pH, and decreased with increasing initialdye concentration.K was proportional to iron loading,and decreased with increasing pH or initial dye concentration.展开更多
文摘水生生态系统 ,特别是海洋无疑是大气 CO2 的一个巨大的汇。海洋对大气 CO2 的汇以及大气圈和海洋之间碳的变换量在很大程度上取决于混合层碳酸盐化学、水中溶解碳的平流传输、CO2 通过空气——海水界面的扩散、海洋生物生产和所产生的有机碳化合物的沉降等 ,现在已建立和发展了多种海洋碳子模型以对 CO2 的汇进行估测。根据国内外研究资料 ,综述了水生生态系统碳循环过程及“生物泵”作用机制等方面的研究进展 ;介绍了两大类主要的海洋碳子模型 :厢式模型和普通环流模型 ,采用这些模型对海洋碳汇的估算约为 1 .2～ 2 .4 Gt C/a;分析了湖泊、河流等对大气 CO2 汇的特点及向海洋的转移 ,并对影响水体生态系统碳循环和大气 CO2
文摘Decoloration of simulated wastewater containing dye reactive black K-BR by zero-valent iron was investigated. The results showed that decoloration efficiency increased with decreasing pH or initial dye concentration, and increased with increasing iron loading. The reaction followed first-order kinetics initially but deviated from first-order behavior with increasing time. Considering the decrease of active surface area of zero-valent iron with time,decoloration kinetics was expressed as ln(c/c 0)=K[1-exp(-k dt)]/k d.It indicated that k d was independent of iron loading and pH, and decreased with increasing initialdye concentration.K was proportional to iron loading,and decreased with increasing pH or initial dye concentration.
