The use of adsorption-active additions of some natural minerals for raising the quality of coagulation purification of natural water

laboratory, pilot and production tests were carried out aimed at the use of powder clinoptilolite jointly with aluminum sulfate to improve the quality of purification of the Dnieper river water. The article showed the advantages of a combined use of these reagents: higher degree of purification, lower consumption of regents, and smaller volume of deposits. The research has begun to obtain composite coagulant by treating with hot sulfuric acid of clinoptilolite and aluminum hydroxide. First research has been conducted of water coagulation under laboratory conditions using composite coagulant and its efficiency was demonstrated.     

Effect of conjugation with biomolecules on photoluminescence and structural characteristics of CdSe/ZnS quantum dots

The photoluminescence and photoluminescence excitation spectra, the X-ray diffraction patterns, and the effect of conjugation with biomolecules upon these characteristics are studied for silanized CdSe/ZnS quantum dots. Along with the band of annihilating excitons in the quantum dots, the luminescence spectra exhibit emission associated with defects. It is established that the emission spectrum of defects involves at least two components. It is shown that the defects are located mainly at the small-sized quantum dots; the defects responsible for the long-wavelength component are located mainly at the quantum dots larger in size than the quantum dots, at which the defects responsible for the short-wavelength component are located. It is found that conjugation with biomolecules induces not only the blue shift of the excitonic band, but transformation of the emission spectra of defects and an increase in the contribution of defects to the luminescence spectrum as well. The changes observed in the emission spectrum of defects are attributed to the formation of certain emission centers. It is shown that, when conjugated with biomolecules, the quantum dots experience increasing compression strains. This effect is responsible for the blue shift of the luminescence band of the quantum dots.