Hebei Key Laboratory of Bioinorganic Chemistry College of Science Agricultural University of Hebei Baoding 071001 China;
Hebei Key Laboratory of Bioinorganic Chemistry College of Science Agricultural University of Hebei Baoding 071001 China;
Hebei Key Laboratory of Bioinorganic Chemistry College of Science Agricultural University of Hebei Baoding 071001 China;
Hebei Key Laboratory of Bioinorganic Chemistry College of Science Agricultural University of Hebei Baoding 071001 China;
Hebei Key Laboratory of Bioinorganic Chemistry College of Science Agricultural University of Hebei Baoding 071001 China;
ultrasound-assisted emulsification; solidified floating organic drop microextraction; flame atomic absorption spectrometry; preconcentration; copper;