Using UV radiation in finishing processes of textile products

W pracy zastosowano promieniowanie UV w jednym z etapów wykończenia, zmierzającego do nadawania płaskim wyrobom włókienniczym właściwości biostabilnych. Na skutek fotochemicznej reakcji naniesionych na tkaninę związków chemicznych pod wpływem promieniowania UV na powierzchni wyrobu włókienniczego wytrąca się metaliczne srebro. W ten sposób wyrób włókienniczy uzyskuje właściwości antybakteryjne i antygrzybiczne. Naświetlanie promieniami UV wykonano w specjalnie skonstruowanym do tego celu laboratoryjnym promienniku. Skuteczność efektu oceniono spektrofotometrycznie.In present investigations we used the UV radiation in one of the stage of finishing processes of textile fabrics to give them biostatic properties. Interaction of UV radiation and the surface of these textiles with a special chemical compounds gives a photochemical response and precipitation of metallic silver. In that way our textiles get a antibacterial and antifungal properties. We used a special UV radiator to radiation the samples and spectrophotometer to estimate the efficiency of this method

Monitoring the evolution of free and cysteinylated aldehydes from malt to fresh and forced aged beer

During storage, beer staling coincides with a gradual increase in the concentrations of aldehydes resulting in the appearance of undesirable flavours. Cysteinylated aldehydes, also referred to as 2-substituted 1,3-thiazolidine-4carboxylic acids, have been proposed as potential precursors of this increase. This study aimed to further understand the origin of aldehydes in aged beer, by monitoring both free and cysteinylated aldehydes throughout the brewing process, from the raw materials until the stored product. Quantification of free and cysteinylated aldehydes was performed for two different brews via headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS), respectively. All selected marker aldehydes were quantified in malt, wort, and the resulting fresh and aged beer samples. Cysteinylated aldehydes were quantifiable in malt and up to the wort boiling phase. The highest levels of free aldehydes were found in malt, whereas cysteinylated aldehydes showed highest levels at mashing-in pointing to their formation during both malting and subsequent mashing-in. During beer ageing, an increase in all free aldehydes was measured. In particular, a rise in 2-methylpropanal and furfural is most striking. Although the presented experimental data obtained on malt and brewery samples do support the concept of bound-state aldehydes, cysteinylated aldehydes cannot be consider as the cause of increasing levels of staling aldehydes during beer ageing