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161.
Influence of yeast on the yield of fermentation and volatile profile of ‘Węgierka Zwykła’ plum distillates 下载免费PDF全文
Katarzyna Pielech‐Przybylska Maria Balcerek Agnieszka Nowak Piotr Patelski Urszula Dziekońska‐Kubczak 《Journal of the Institute of Brewing》2016,122(4):612-623
The character of plum brandies depends on a unique aroma profile of the plum and the microbiota present on the surface of the fruits, as well as yeast used for fermentation. In this study, an evaluation of the effect of microorganisms applied for the fermentation of W?gierka Zwyk?a var. plum mashes and processing temperature (18 °C, 30 °C) on its efficiency and volatile profile, as well as taste and flavour of distillates obtained was performed. An estimation of the odour activity values (OAVs) of the volatile compounds was also conducted. Regardless of whether the fermentation was carried out using Saccharomyces bayanus wine yeast or by native microflora present on plums as well as raisins, the efficiency of this process was high and ranged between 91.7 and 96.7% of the theoretical efficiency. Especially rich in esters (among others ethyl acetate and isoamyl acetate) was the distillate derived after fermentation with the microflora of plums and raisins, at 18 °C. An evaluation of the individual aromatic effect of chemical compounds present in tested distillates, in terms of their OAVs, revealed that the highest OAVs were reached with isovaleraldehyde. Other compounds that showed aroma values >1 and possibly had an effect on the overall aroma of tested plum distillates were the following: hexanal, benzaldehyde, ethyl acetate, isoamyl acetate, ethyl benzoate, ethyl hexanoate, 1‐propanol, 2‐methyl‐1‐butanol, 3‐methyl‐1‐butanol and 1‐hexanol. The performed sensory ranking showed that the best rated distillate was the one obtained after fermentation with the indigenous microflora of plums and raisins, at 18 °C. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
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Moskalewicz Tomasz Zych Anita Łukaszczyk Alicja Cholewa-Kowalska Katarzyna Kruk Adam Dubiel Beata Radziszewska Agnieszka Berent Katarzyna Gajewska Marta 《Metallurgical and Materials Transactions A》2017,48(5):2660-2673
Metallurgical and Materials Transactions A - In this study, microporous composite sol–gel glass/polyetheretherketone (SGG/PEEK) coatings were produced on the Ti-13Nb-13Zr titanium alloy by... 相似文献
163.
Ewa Langer Małgorzata Zubielewicz Helena Kuczyńska Agnieszka Królikowska Leszek Komorowski 《腐蚀工程科学与技术》2013,48(7):627-635
ABSTRACTTypically, an anticorrosive coating system for long-term protection consists of a primer, one or several intermediate coats, and a topcoat. In such systems, zinc-rich primers are often used as they ensure good adhesion to the substrate and protect it from corrosion. Such coatings are very highly pigmented, which sometimes leads to losses in cohesive strength and deterioration of mechanical properties. Furthermore, Zn is known to be harmful to the environment. In this work we present Zn primers with reduced Zn content and better protective properties than traditional zinc-rich primers. The formulations of different Zn pigments in the epoxy matrix were developed with the concentration of zinc particles reduced to about 50% in the dry coating. To evaluate the distribution of pigments scanning electron microscopy has been employed. The anticorrosive properties were tested using the salt spray test and electrochemical impedance spectroscopy. The mechanical properties of the coatings were also tested. 相似文献
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Anna Knapik Alicja Drelinkiewicz Anna Waksmundzka-Góra Agnieszka Bukowska Wiktor Bukowski Jaroslaw Noworól 《Catalysis Letters》2008,122(1-2):155-166
Functional gel type resins of various crosslinking degrees (3–20%) with C=O and carboxylic groups were used as the supports
for Pd catalysts (0.5–2 wt% Pd). The role of polymer properties was studied in the hydrogenation of 2-Butyne-1,4-diol (B3-D)
to alkene (B2-D) and alkane (B1-D). Hydrogenation was studied at atmospheric pressure of hydrogen using THF, H2O and THF + H2O mixtures as the solvents. Systematic studies were carried out to determine the role of the type of solvent, crosslinking
degree of polymer, the content of Pd in catalysts, initial B3-D concentration and the procedure of catalyst reduction in activity/selectivity
behaviour of catalysts. Swelling degree of polymer matrix under the catalytic run exhibits crucial role in the activity and
selectivity to alkene, B2-D. In the presence of highly expanded catalyst (THF solvent, 3% crosslinking degree, 1 wt% Pd) the
alkyne, B3-D, is hydrogenated to alkene, B2-D, with selectivity ca. 85% up to high B3-D conversion (90%). The suppression
of alkene to alkane hydrogenation in the stage of B3-D is ascribed to high ability of Pd centres in the Pd/OFP catalysts to
strong adsorption of alkyne substrate. It may also be related to steric hindrances of polymer in the vicinity of active Pd
centres. At small content of added water (5% by vol.) to THF the catalysts offer very attractive performance in terms of activity
and 98% selectivity to alkene. Water facilitates interactions of B3-D with functional groups of polymer that leads to better
expansion of polymer matrix and more effective suppression of alkene hydrogenation in the alkyne stage. 相似文献
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The reaction of CaO with CO(2) is a promising approach for separating CO(2) from hot flue gases. The main issue associated with the use of naturally occurring CaCO(3), that is, limestone, is the rapid decay of its CO(2) capture capacity over repeated cycles of carbonation and calcination. Interestingly, dolomite, a naturally occurring equimolar mixture of CaCO(3) and MgCO(3), possesses a CO(2) uptake that remains almost constant with cycle number. However, owing to the large quantity of MgCO(3) in dolomite, the total CO(2) uptake is comparatively small. Here, we report the development of a synthetic Ca-rich dolomite using a coprecipitation technique, which shows both a very high and a stable CO(2) uptake over repeated cycles of calcination and carbonation. To obtain such an excellent CO(2) uptake characteristic it was found to be crucial to mix the Ca(2+) and Mg(2+) on a molecular level, that is, within the crystalline lattice. For sorbents which were composed of mixtures of microscopic crystals of CaCO(3) and MgCO(3), a decay behavior similar to natural limestone was observed. After 15 cycles, the CO(2) uptake of the best sorbent was 0.51 g CO(2)/g sorbent exceeding the CO(2) uptake of limestone by almost 100%. 相似文献
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