REDOX POTENTIAL OF SELENIUM IN YONGSHOUKASCHIN-BECK DISEASE REGION AND THE INFLUENCEOF HUMIC ACID ON EH [Se(VI)/Se(IV)]
永寿大骨节病区硒的氧化还原电位及腐殖酸等的影响

The relation between EH Se(VI)/Se(IV)] and pH of soil solution in Kaschin-Beck Disease region and the effects of natural redox agents, namely humic substances, MnO2 and Fe2+, on the redox property of the system were studied. The results indicated that both humic acid and Fe2+ could enhance the reducibility of Se(VI)/Se (IV) and MnO2 had a limited dxidisability for Se(IV). Fe2+ showed a week reducibility only at low pH value. The reducibilities of three sulfur-containing compounds for Se(VI) were in following order. sulfo-ethanol acid > L-cystine > sulfide.