Paper presents the results of testing the corrosion resistances of three stainless steels during the fermentation of a specific probiotic drink – kefir. Experiments were conducted using preliminary - activated kefir grains as a starter culture. The two best corrosion performance steels differed mainly in Mo and Nb content. Our results indicated that niobium played the most protective role against corrosion during kefir fermentation, since steel with no Mo content but only Nb demonstrated the lower corrosion rate.
COBISS.SI-ID: 14809622
Approximately 25 cm * 25 cm large sheets of crosslinked highly porous poly(glycidyl methacrylate-co-ethyleneglycol dimethacrylate-co-ethylhexyl methacrylate) membranes with an average thicknesses between 285 and 565 micrometers were prepared by casting a high internal phase emulsion (HIPE) containing monomers onto glass substrates and subsequent polymerisation. Open cellular porous polyHIPE type membranes were obtained with large pores (cavity) sizes between 3 and 10 micrometers while interconnecting pores were between 1 and 3 micrometers. The percentage of ethylhexyl acrylate and ethyleneglycol dimethacrylate influenced the flexibility and morphology of the resulting membranes. Porous membranes were chemically modified with diethylamine to yield functionalised supports for ion exchange chromatography. Cylindrical housings were used for positioning of the membranes and allowing flow of the mobile phase. Pulse experiments were used to study the flow characteristics and a homogeneous flowthrough the entire area of the membrane was found. Bovine serum albumin was purified by a 8 ml column containing functional membrane in modular shape;dynamic binding capacity was measured to be as high as 45 mg/ml.
COBISS.SI-ID: 14668054
High internal phase emulsions are used to prepare cross-linked polystyrene/poly(acrylic acid) (PS/PAA) and polystyrene/poly(N-isopropyl acrylamide) (PS/PNIPAM) monoliths with a polystyrene scaffold and acrylic domains inside the cavities of the scaffold. Acrylic acid or NIPAM are included in the aqueous phase of a high internal phase emulsion, while the oil phase includes styrene. Polymerisation of such high internal phase emulsions (HIPEs) yields macroporous polymers (polyHIPEs) with a scaffold composed of cross-linked polystyrene and domains of cross-linked poly(acrylic acid) or cross-linked poly(NIPAM) positioned inside the cavities of the polystyrene skeleton. Monolithic discs are shaped from PS/PAA and PS/PNIPAM polyHIPEs in order to study the dependence of flow resistance through the discs in relation to pH or temperature changes. The amount of acrylic component in the aqueous phase and the degree of cross-linking prove to be the most influential on the pressure drops of columns with monolithic discs. The temperature influences the resistance properties in the case of PS/PNIPAM material. Inverse size exclusion chromatography experiments confirm the pH dependent structure of the polymeric monoliths.
COBISS.SI-ID: 15235350