[IEEE 2011 International Conference on Computer Distributed Control and Intelligent Environmental Monitoring (CDCIEM) - Changsha, Hunan, TBD, China (2011.02.19-2011.02.20)] 2011 International Conference on Computer Distributed Control and Intelligent Environmental Monitoring - Relationships between Changes of Three Organic Acids (Oxalic Acid, Citric Acid and Tartaric Acid) and Phytoextraction by Sunflower (Helianthus annuus L.) in Sand Cultures Contaminated with Cadmium and Lead