Abstract:Poly(acrylic acid) (PAA) polymer modified with poly(ethylene glycol) (PEG) was used as a dispersant in preparation of hydroxyapatite aqueous suspension. The effect of dispersant structure on suspension stabilization was investigated through the studies of physicochemical properties of the obtained dispersions. Novel dispersants and HAp suspensions were characterized using pH and viscosity measurements.
Abstract:Acrylic acid modified with poly(vinyl alcohol) was used in preparation of polymer matrix. The synthesis of hydrogels in aqueous solution was carried out under microwave irradiation. The effect of polymerization conditions on swelling capacity was investigated. Results showed that the swelling capacity was affected by various doses of poly(vinyl alcohol). These polymers were characterized by swelling in distilled water and 0.9% NaCl solution, as well as by in vitro investigations in Ringer’s solution.
Abstract:In this study, a series of hydrogels was prepared by formation of crosslinked acrylic acid networks, modified by gelatine. The rate of swelling of prepared hydrogels in different distilled water was studied as a function of NMBA concentration on the polymeric matrix. Novel materials were characterized using in vitro investigation in SBF. Results showed that the pH value was affected by gelatine concentration in hydrogel.
Abstract:Whey, for years considered waste in the dairy industry, is now more often treated as a valuable raw material for further processing. Chemically, whey contains lactose, proteins, fats, lactic acid, B group vitamins and minerals, so it can be also a natural source of valuable cosmetic components, e.g. hydrocolloids. Apart from biological activity, the functional properties of whey proteins like binding water, stabilizing foams or emulsifying properties are worthy of attention. In this work, properties of shampoos containing ultra-filtrate of cow’s, sheep’s and goat’s milk whey were evaluated. An influence of their origin on qualities of cosmetics was examined. The obtained result showed that whey could be successfully used in hair shampoo formulation.
Abstract:A very important environmental problem around the world is spontaneously or artificially arising pollution of water and sewage. One of such pollutants are nitrogen compounds. Current methods and apparatus used to eliminate or reduce the occurrence of these compounds in water and wastewater are presented in the paper. Also the latest developments in reducing nitrogen pollution are discussed.
Abstract:The paper presents method of utilization of meat bone-meal (MBM) and the results of researches of obtained ashes that can be then used as a sorbent to removal heavy metals ions from the solutions. Physical properties of ashes obtained at 750°C that have influence on sorptive ability, were examinated: specific surface, volume and size of pores, grain-size distribution of material, open and close porosity. The structure of the material was observed. The removal degree of cadmium and zinc from model solutions, that were in contact with the ash, was determined.
Abstract:The goal of this paper is to show new possibilities of the natural waste pozzolana utilization. First, waste diatomaceous earth containing higher portion of clay minerals - which is not suitable for filter use in food industry - was chosen for our experimental work. Our tests were focused on the study of preparation of cementitious binders containing waste diatomaceous earth. Standard cement pastes with 10%, 15%, 20% and 30% replacement of cement with calcined waste diatomite were examined, calcination temperature was 650°C. Simultaneously technological properties of prepared binders were tested and results were compared with the standard for Portland cement. Our binders with diatomaceous earth showed slightly lower early strengths but favourable higher long-term compressive strength and lower heat of hydration. Next our attention was given to another waste pozzolana, waste kieselguhr sludge generating during deep bed filtration of beverages (wine, beer, juice). The kieselguhr is prepared from diatomaceous earth by crushing, drying and calcining at temperature 800–1200°C successively. Currently, the most frequent disposal method is to spread the used kieselguhr over agricultural land. Presently basic chemical, physical and technological tests of a sample of kieselguhr waste coming from Czech brewery are taking place.
Abstract:The human sense of smell is certainly the most versatile apparatus to analyze smells, but measurements take a lot of time and require employing a group of trained people . Other techniques, like gas chromatography, allow to obtain accurate data of the chemical composition of examined gas, but do not inform about the real nature of smell. To identify the odour, devices comparing and determining its nuisance are used; in scientific literature they are called ‘electronic noses’. In conveyed measurements a device was used with an array of eight resistive TGS Figaro gas sensors of 2600 series, each of which reacted to another class of a chemical compound . Response of gas sensor array was collected for a mixture of air with odour-active compounds like dimethylamine, acetic acid, benzaldehyde of different concentrations. For the analysis of odour profiles there were used artificial neural networks with one hidden layer, containing from several to tens of neurons.
Abstract:In the present study we synthesized a series of HAp-PAA/PEG hydrogel composites with various HAp contents under microwave irradiation. Novel composites were characterized using Fourier transform infrared spectroscopy (FT IR) and in vitro investigations (Ringer’s solution).