Inna Juhnevica

Effect of Siliceous Pozzolanic Additives on the Hydration Process of Cement

The given study investigates the influence of pozzolanic admixtures both micro- and nanosize silica and biomass ashes on microstructure and properties of hydration process of cement paste. The investigations were carried out by - XRD, SEM and FTIR. Pozzolanic activity of the concrete admixtures strongly depends on their chemical composition, content of reactive silica as well as the specific surface area. The micro- and nanosilica pozzolanic additives demonstrated the higher values of pozzolanic activity. Those activate the process of mineralization and are acting both as the cementitious admixture as well as the fine filler.

Characterization of Iron Oxide Nanoparticles for Sol-Gel Dip-Coating Method Prepared Thin Films

The paper describes two methods of syntheses of iron oxides, microstructure and morphology of magnetite nanoparticles. Nanocomposite thin films of SiO2/Fe3O4 have been prepared with sol-gel dip coating technique: dip-coating from SiO2/Fe3O4 sol and encapsulation magnetite between two SiO2 layers. Structural and morphological characteristics of iron oxides particles and prepared film were analyzed by X-Ray Diffraction, SEM, FTIR, DTA, AFM. AFM topography of surface and measurements of roughness has shown that using iron oxide encapsulation between two SiO2 layers to provide the even distribution of iron oxide, results as high quality films with low Rq values 1.5 2.7 nm.