Ellis Andre S, Johnson Thomas M, Bullen Thomas D
Department of Geology, University of Illinois at Urbana-Champaign, 245 Natural History Building, Urbana, IL 61801, USA.
Science. 2002 Mar 15;295(5562):2060-2. doi: 10.1126/science.1068368.
Measurements of chromium (Cr) stable-isotope fractionation in laboratory experiments and natural waters show that lighter isotopes reacted preferentially during Cr(VI) reduction by magnetite and sediments. The 53Cr/52Cr ratio of the product was 3.4 +/- 0.1 per mil less than that of the reactant. 53Cr/52Cr shifts in water samples indicate the extent of reduction, a critical process that renders toxic Cr(VI) in the environment immobile and less toxic.
实验室实验和天然水体中铬(Cr)稳定同位素分馏的测量结果表明,在磁铁矿和沉积物对Cr(VI)的还原过程中,较轻的同位素优先发生反应。产物的53Cr/52Cr比值比反应物低3.4±0.1‰。水样中53Cr/52Cr的变化表明了还原程度,这是一个关键过程,可使环境中有毒的Cr(VI)变得不活跃且毒性降低。