Papers by Author: Yan Ming Yang

Abstract: Hydroxyapatite (HAP) was synthesized in Triton X-100 microemulsion and was characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS). Particle size analysis results showed that the particles has nanometer size, high surface area and loose structure. The prepared HAP had high adsorption capacity to human serum protein and the adsorption of human serum protein on the surface of HAP was confirmed by SEM. The factors which influenced the adsorption capacity such as the acidity, reaction time and the concentration of adsorbent were investigated in detail and the adsorption isothermal was also obtained. The adsorption capacity reduced while the pH value increased, and the adsorption reached equilibrium when shaking time was up to 40 min. The adsorption isotherm could be fitted by the pseudo-Langmuir type. The adsorption of human serum albumin on HAP was investigated, and the influences of adsorption on the conformation of human serum albumin were studied by infrared and ultraviolet spectroscopy. It can be seen from the FT-IR spectra that the intensity of flex vibration of C=O, N-C bonds all weakened. The calculation results of ultraviolet spectrum indicated that the quantity of α spiral structure reduced from 44% to 17.12%.

Abstract: We obtained the Eu(TTA)3phen•H2O-PVP composite film by rare earth complexes Eu(TTA)3 phen•H2O was doped intentionally in polyvinylpyrrolidone(PVP), and the factors of effect it’s luminous intensity were investigated. The results indicate that the luminous effect of sample was best when the water and the alcohol proportion is 1: 4 in the resolver, the aggregation-time reached 12 h and the doping concentration of europioun ion reached 0.6%. The infrared spectrum analyses of sample indicate that there is an interaction between Eu(TTA)3phen•H2O and PVP. In addition, the fluorescence spectra and ultraviolet spectrum analyses of sample indicate that polymer materials can not only fix rare earth ions to enhance its luminescence intensity, but also avoid the quenching effect to rare earth caused by water molecule, through the replacement of PVP ligand to water molecule in the complex. The luminous intensity of the rare earth complexes can be greatly enhanced, and the composite film contained high amount of rare earth complexes is obtained, which laid a foundations for further study the film formation properties of rare earth complexes luminous materials.