Removal of lead using xanthated marine brown alga, Undaria pinnatifida

Sulphur groups were introduced onto the cell surface of Undaria pinnatifida to increase the sorption capacity for lead ions. The total sulphur content of the cell approached 13.8% (w/w) through xanthation. Xanthate groups introduced onto the cell wall of Undaria pinnatifida enabled the biomass to adsorb lead ion three times more than the control and the sorption capacity approached 1000 mg lead g(-1). Increased affinity for lead ions was thought to be due to the fact that sulphur groups have the ability to make strong sulphur-metal complexes compared with that of the carboxyl group. The removal efficiencies of several metal ions were changed for various pH conditions. Since the removal order was; Cu2+ = Cd2+ = Pb2+ much greater than Ni2+ = Zn2+ > Co2+ much greater than Ca2+ > Mg2+, the selective adsorption for lead, cadmium and copper ions was possible. (C) 1999 Elsevier Science Ltd. All rights reservedclose283

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Abstract Background: Spondylolisthesis is the major cause of refractory low back pain. There are many studies of the surgical treatment of spondylolisthesis, but few of conservative treatments. There is also no optimal conservative treatment protocol, however, low back pain caused by low-grade spondylolisthesis is controlled with non-surgical pain management. Acupuncture has become a useful method for treating low back pain, but there has not been any study of its efficacy in relation to spondylolisthesis. This study was designed to establish the feasibility of a randomized controlled trial and the safety of acupuncture for low back pain due to low-grade spondylolisthesis