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Phân tích tư tưởng của nhân dân qua đoạn thơ: Những người vợ nhớ chồng… Những cuộc đời đã hóa sông núi ta trong Đất nước của Nguyễn Khoa Điềm
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A large amount of information has accumulated on humic acids andrelated substances, which warrants the creation of an independentscience of humic compounds. Two different concepts have emergedfrom the maze of data, one claiming humic compounds to beoperational or fake compounds, produced by the analytical extractionprocedures, and the other considering them to be natural compoundsoccurring in soils, rivers, lakes, oceans and their sediments.
Nội dung trích xuất từ tài liệu:
Humic Matter in Soil and the Environment Principles and Controversies
