@article{KumkeEidnerKrueger2005,
  author    = {Kumke, Michael Uwe and Eidner, Sascha and Kr{\"u}ger, Tobias},
  title     = {Fluorescence quenching and luminescence sensitization in complexes of Tb3+ and Eu3+ with humic substances},
  year      = {2005},
  abstract  = {Intrinsic fluorescence quenching of humic substances (HS) and the sensitization of Ln(3+) luminescence (Ln3+ Tb3+, Eu3+) in HS complexes were investigated. Both measurements yielded complementary information on the complexation of metals by HS. Large differences between fulvic acids(FA)and humic acids (HA) were found. From time-resolved luminescence measurements it is concluded that a combination of energy transfer and energy back transfer between HS and Ln(3+) is responsible for the observed luminescence decay characteristics. In the case of Eu3+, an additional participation of charge-transfer states is suggested. A new concept for the evaluation of the sensitized luminescence decays of Ln(3+) was adapted},
  language  = {en}
}