The problem of poor biodegradability of residual organic matters in WWTP Tailwater was studied,with fulvic acid taken as an example.Lanthanum(La) and nitrogen(N) co-doped TiO_2 photocatalyst was synthesized by sol-gel method,and its structure and properties were characterized by XRD and UV-Vis.The effects of doped amount of La and N on photocatalytic degradation performance of fulvic acid were investigated,and the effects of photocatalytic degradation on the three-dimensional fluorescence characteristics,UV...