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  • Author: Małgorzata Cieślak x
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Abstract

Aerogels are characterized by excellent insulation properties and a good resistance to high and low temperatures. The objective of this study was to investigate the effects of silica aerogel on thermal properties of textile–polymer composites. Aerogel was applied in protective clothing fabric to improve its heat resistance. The composites were produced by coating a fabric made of meta-aramid (polyamide–imide) yarns with a dispersion of polychloroprene latex and synthetic resins or an acrylic–styrene dispersion with aerogel (100–700 μm particle size). The composites were subjected to thermal radiation (20 kW/m2) and their thermal properties were determined by thermogravimetry/derivative thermogravimetry (TG/DTG). Scanning electron microscopy/X-ray energy dispersive spectroscopy (SEM/EDS) was used to characterize the microstructure and study the elemental composition of materials. The thermal conductivity and resistance of composites were measured with an Alambeta apparatus. The tests indicated an increase in resistance to thermal radiation by approximately 15–25%. In TG/DTG analysis, the initial temperature for an unmodified fabric was 423.3°C. After modification, it decreased to 361.8° and 365.3°C for composites with 7 and 14% of aerogel, respectively. SEM images revealed a reduction in aerogel particle size.

Abstract

The aim of this study was to track the changes in blood parameters of mid-lactation multiparous Polish Holstein-Friesian cows in response to a diet supplemented with a mixture of fish-soybean oils blend and tannin-containing lingonberry shrub (Vaccinium vitis idaea; VVI) extract. Twelve lactating cows were randomly assigned to a crossover design of two treatments (6 cows per treatment) which consisted of a control diet containing no supplement (CON) and CON supplemented with a mixture of 99 g of VVI leaves extract and 660 g of blended fish-soybean oils (MIX) daily. The obtained results showed a significant increase in plasma glucose level, as well as C18:1t11 and n-3 fatty acids proportion. A significant decrease was also observed in insulin concentration, triglyceride and C18:0 proportion. Generally, the saturated fatty acid proportion decreased while the unsaturated fatty acid significantly increased with the MIX diet. In conclusion, using supplements of a mixture of VVI extract and fish-soybean oils blend modulated the unsaturated fatty acid proportion in blood, without affecting the dairy cows’ blood parameters which were all within the normal ranges.

Abstract

The article presents research results of the introduction of powdery activated carbon to the existing technological system of the groundwater treatment stations in a laboratory, pilot plant and technical scale. The aim of the research was to reduce the content of organic compounds found in the treated water, which create toxic organic chlorine compounds (THM) after disinfection with chlorine. Nine types of powdery active carbons were tested in laboratory scale. The top two were selected for further study. Pilot plant scale research was carried out for the filter model using CWZ-30 and Norit Sa Super carbon. Reduction of the organic matter in relation to the existing content in the treated water reached about 30%. Research in technical scale using CWZ-30 carbon showed a lesser efficiency with respect to laboratory and pilot-plant scale studies. The organic matter decreased by 15%. Since filtration is the last process before the individual disinfection, an alternative solution is proposed, i.e. the second stage of filtration with a granular activated carbon bed, operating in combined sorption and biodegradation processes. The results of tests carried out in pilot scale were fully satisfactory with the effectiveness of 70–100%.

Abstract

This study examined the potential effects of Saponaria officinalis (SO) or Panax ginseng (PG) saponins supplemented to diets differing in the proportion of forage to concentrate on rumen microbial fermentation and methane production in vitro. Two experiments were carried out using the rumen simulation technique (RUSITEC). In the first experiment the substrate was comprised of a mixture of meadow hay and corn meal in a ratio of 60:40 dry matter (DM; high forage diet; HF). In the second experiment low forage diet (LF) consisting of meadow hay and corn meal in the ratio of 40:60 DM was used. Diets were supplemented with dried roots of SO or PG to provide 1% of triterpenoid saponins in dietary dry matter. All triterpenoid sources significantly (P≤0.05) decreased number of protozoa, by 50% and 72% respectively when HF diet was analysed (first experiment). There were no changes in methane production. In the second experiment (LF), the potential to mitigate methane production was reported for both SO and PG addition, however only in PG a decrease in the protozoal population was detected. Supplementation of plants rich in triterpenoid saponins has been identified as a diet dependent potential factor which has an important role in modulation of rumen fermentation processes. However, further studies are needed to evaluate their effect in animal production.