| 摘要 |
<p>Covalent complexing ligands are prepared by condensing urea with formaldehyde and an alkali metal cyanide in the presence of hydrogen cyanide and alkanol ureas with low molecular weights, such as mono- and dimethanolurea, etc. Complex formation of these ligands with metals, which are important for plant growth, is widely applicable in agriculture. Also useful in metallurgy and detergents.</p> |
