Synthesis And Thermochemistry Study Of Rare Earth Complexes With Amino Acids

Rare earth elements have many unique biochemical properties and amino acids are the basic units of biology. Since several decades of years, with great progression being made in cognition and researching of the complexes of rare earth ions with amino acids, the complexes have been used in many areas, such as fertilizer, pesticide and antibacterial agent and so on.In the present thesis, the complexes of rare earth ions with amino acids, including binary complexes, ternary binary complexes, and heteronuclear complexes, were synthesized in aqueous solution and characterized by element analysis, IR spectrum, XRD analysis. The results suggest that new complexes, which are worthy of research and have biologic properties, have been made successfully.Using a high precision automatic adiabatic calorimeter, a differential scanning calorimeter (DSC) and thermogravimetric analyzer (TG), the thermal properties of the complexes were studied and the laws were summarized.The phase transitions of the new complexes at about 220 K and 246 K were discovered. The thermodynamic data of the phase transition, such as temperatures, enthalpies and entropies were calculated and the mechanism was deduced to be the orientational order/disorder process of perchlorate ions.Low-temperature heat capacities of the complexes were measured and fitted in the temperature range from 80 to 390 K. The thermodynamic functions [HT -H298.15] and [ST -S298.15] were derived from the heat capacity data withtemperature interval of 5 K.Finally, microcalorimetry was used to study the action of the complexes of rare earth ions with amino acids on Escherichia coli. Found that the complexes have inhibitory effects on E. Coli.