Evolution of extinction spectra of monolayer plasmon-resonant colloidal crystals in the process of their synthesis by the moving meniscus method

Regularities of the evolution of the extinction spectra of periodic colloidal structure composed of silver nanoparticles formed from bulk hydrosol on the surface of dielectric substrate are studied using the moving meniscus method. Spectra were calculated by the coupled dipole method. The effect of individual parameters of disperse system on the pattern of extinction contour in the band of plasmon absorption of a synthesized two-dimensional crystalline structure is analyzed.     

Isotopic catalysis and isotopic analysis

Isotopes with magnetic nuclei accelerate the biochemical reactions of adenosine triphosphate synthesis by a factor of two to three. An isotope effect in which isotopes are preserved in the reaction system is known as isotopic catalysis. It has been revealed in enzymatic reactions catalyzed by magnesium, zinc, and calcium ions. Isotopic catalysis is sensitive to paramagnetic impurities, which inhibit it. It is shown that the presence of paramagnetic iron ions eliminates isotope effect and suppresses the isotopic catalysis of adenosine triphosphate synthesis.     

Mikrochemie

Ohne Zusammenfassung     

Specific features of absorption spectra of fractal-structured silver sols

Effects exerted on plasmon absorption spectra by different characteristics of aggregating silver sols with a fractal distribution of particles whose sizes are in the range 5–30 nm are studied by mathematical simulation with the aid of a modification of the method of coupled dipoles. Distinctive features of plasmon absorption contours of silver sols having different particle-size distribution functions and different properties of the adsorption layers of the particles are explained.