Odolnost povrchové úpravy nábytkových dílců vůči opakovanému působení zvolených studených kapalin a tělových krémů

This thesis focuses on the resistance of furniture finishes to exposure to selected cold liquids and hand creams. The theoretical part elaborates the requirements for the surface treatment of furniture parts finished with different pigment and transparent coating systems. Factors that can influence the resulting finish are also presented. Current technologies for the application of transparent and pigment coatings are discussed. The experimental section deals with laboratory verification of the resistance of selected transparent and pigment coating systems, particularly for resistance to cold liquids and selected body creams. The effect on the aforementioned resiliences has been verified for the coating systems with crosslinker. Beech wood board, oak and beech veneers were chosen as the substrate material for the selected transparent systems. For the pigment coating systems, MDF was chosen as the substrate material. These backing materials were chosen because they are the most widely used in the furniture market. The chosen pigment and transparent systems were applied to the backing materials. The samples were then conditioned for 1 month in laboratory conditions (temperature: 23 °C, relative humidity: 50 %) and then subjected to qualitative verification of the physical, mechanical and chemical resistance on the finished surface

Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation

Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest flux was achieved with the thinnest membranes and the best energy efficiency was achieved with the thickest membranes. All membranes had salt retention above 99%. Nanotechnology offers the potential to find modern solutions for desalination of waste waters, by introducing new materials with revolutionary properties, but new membranes must be developed according to the target application