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101.
Violeta T. Pardio Krzysztof N. Waliszewski Paula Zuñiga 《International Journal of Food Science & Technology》2011,46(2):305-314
Biochemical, microbiological and sensory changes during shelf‐life at ?1 °C were determined in shrimp (Panaeus aztecus) previously dipped in ascorbic acid, citric acid, potassium sorbate and 4‐hexyl resorcinol solutions using face‐centred central composite design. Microbiological count, trimethylamine and hypoxantine production were measured. The lowest level of the total psychrotrophic bacteria, hypoxantine and trimethylamine were found in samples dipped in all containing chemicals solutions comparing to control treatment. Sensory studies showed that treatment A (ascorbic acid 4.50, citric acid 0.12, potassium sorbate 18.60 and 4‐hexyl resorcinol 0.25, all g L?1) and B (ascorbic acid 4.37, citric acid 1.26, potassium sorbate 7.03 and 4‐hexyl resorcinol 0.25, all g L?1) did not alter the typical sensory features of shrimp and were effective at delaying the bitter off‐flavour formation for 26 days. This study constitutes a promising alternative to extent shelf‐life of shrimp kept at ?1 °C without freezing. 相似文献
102.
Bartosz Tylkowski Krzysztof A Bogdanowicz Veronica Ambrogi Albena Lederer Violetta Patroniak Marta Giamberini 《Polymer International》2014,63(2):315-326
A liquid crystal polyester and two liquid crystal copolyesters containing α‐methylstilbene moieties and aliphatic or aromatic spacers in the backbone were synthesized in good yields, with the aim of using them for photosensitive microcapsule preparation. The synthesized polymers were fully characterized with respect to thermal stability, type of mesophase, molecular weight and E–Z photoisomerization. Combination of monomers with different structures allowed adjustment of the polymer characteristics such as degree of crystallinity and glass transition temperature, as verified using X‐ray diffraction, polarized optical microscopy and differential scanning calorimetry. Quantitative 1H NMR and UV‐visible experiments were performed in order to investigate E–Z photoisomerization after photoirradiation at 364 nm. Finally, a membrane based on one of these polymers was prepared and it was found that its wettability increased on photoirradiation. © 2013 Society of Chemical Industry 相似文献
103.
Electric arc furnace dusts are among the most environment polluting wastes. Numerous utilization technologies have been developed for dusts containing up to 4% of Zn and more than 20% of Zn. However, the remaining part of steelmaking dusts are the most problematic ones, as they are mostly dumped generating costs and posing serious environmental threats. This paper provides an analysis of the potential utilization options for dusts containing ca. 10% of zinc generated in a single electric steelmaking shop. Physical and chemical properties of dusts have been determined and examined, and furthermore, results of the studies on the EAFD utilization in production of cement clinker and industrial glass have been discussed. It has been found that a particularly beneficial feature of the production technology proposed is that the iron content exceeds 30%. The influence of the dusts used on the functional properties of the products obtained has been established as well as the environmental impact of the processes and products in question and the dust mass possible to be utilized in the production technology proposed have been determined. 相似文献
104.
Michał Sójka Elżbieta Klimczak Jakub Macierzyński Krzysztof Kołodziejczyk 《European Food Research and Technology》2013,237(6):995-1007
The objective of the present work was to determine the nutrient and polyphenolic composition of dried strawberry press cake (SPC), as well as that of its seedless fraction, termed exhausted strawberry flesh (ESF). The study materials were obtained over three consecutive years from an industrial facility manufacturing concentrated fruit juices. On average, SPC consists of 40 % seeds, 3.5 % sand, and about 55 % ESF. In the dry matter of SPC and ESF, the mean content of fat is 9.8 and 3.5 %, protein 17.3 and 20.4 %, and total polyphenols 3,449 and 5,410 mg/100 g, respectively. Both materials are rich in total dietary fiber, whose content amounts to 60 %. The predominant polyphenols in SPC and ESF are flavanols and ellagitannins, which collectively constitute over 95 % of the determined total polyphenol content. In ESF composition, of note is the high content of the strawberry ellagitannin, agrimoniin, which is approximately 1,000 mg/100 g DW (dry weight). SPC has the disadvantage of being highly contaminated with sand (3.4 %), which accumulates in ESF (5.6 %). However, as compared to SPC, ESF contains approximately 20 % more proteins and almost three times less fat. Based on our results, it appears that SPC may be considered a potential raw material for seed recovery. Moreover, dried strawberry press cake, and especially its seedless fraction (ESF), despite substantial contamination with sand, may be used as rich and widely available raw material for the extraction of proanthocyanidins and/or ellagitannins, and especially dimeric agrimoniin. 相似文献
105.
106.
X-ray Photoelectron Spectroscopy (XPS) was used to study the influence of low energy Ar+ ion bombardment, electron bombardment and Pt deposition on the SrTiO3 (STO) single crystal electronic structure. Atomic composition changes were found and attributed to chemical reconstruction of the STO surface. A clear correlation between the presence of conducting, low Ti oxidation states in valence band and core level changes was detected. A strong effect caused by electron irradiation was ascribed to the electroreduction process. The influence of lanthanum doping on surface instability of STO was also discussed. The La doped sample (STO: 3,75% La) was found to be modified upon Pt metal deposition to a higher degree than pure STO crystal. 相似文献
107.
Two-component films of a non-amphiphilic azo dye and a liquid crystal with strongly polar –CN group were studied at an air–water interface on the basis of the surface potential–mean molecular area dependence recorded simultaneously with the surface pressure–mean molecular area isotherm. Additionally, the morphology of the films was monitored with the aid of Brewster angle microscope. A conventional Langmuir technique was used to form dye/liquid crystal films during reduction and expansion of an area occupied by the molecules. From the surface potential value, the effective dipole moment in the first monolayer formed on the water was calculated. Moreover, the number of molecules with dipole moments directed from the water to the air with respect to those directed towards water was estimated. The influence of the two components' miscibilities upon the surface potential after addition of the dye to the liquid crystal was determined. 相似文献
108.
109.
Lukasz A Kurgan Krzysztof J Cios Scott Dick 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(1):32-53
Business intelligence and bioinformatics applications increasingly require the mining of datasets consisting of millions of data points, or crafting real-time enterprise-level decision support systems for large corporations and drug companies. In all cases, there needs to be an underlying data mining system, and this mining system must be highly scalable. To this end, we describe a new rule learner called DataSqueezer. The learner belongs to the family of inductive supervised rule extraction algorithms. DataSqueezer is a simple, greedy, rule builder that generates a set of production rules from labeled input data. In spite of its relative simplicity, DataSqueezer is a very effective learner. The rules generated by the algorithm are compact, comprehensible, and have accuracy comparable to rules generated by other state-of-the-art rule extraction algorithms. The main advantages of DataSqueezer are very high efficiency, and missing data resistance. DataSqueezer exhibits log-linear asymptotic complexity with the number of training examples, and it is faster than other state-of-the-art rule learners. The learner is also robust to large quantities of missing data, as verified by extensive experimental comparison with the other learners. DataSqueezer is thus well suited to modern data mining and business intelligence tasks, which commonly involve huge datasets with a large fraction of missing data. 相似文献
110.