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501.
502.
Joanna Raczkowska Grzegorz Mielcarz Alan Howard Michał Raczkowski 《International Journal of Food Properties》2013,16(3):514-522
Ultra performance liquid chromatography–photodiode array detection (UPLC–PDA) was used to analyze five biologically active polyphenolic compounds (catechin, epicatechin, rutin, trans-resveratrol, and quercetin) in different types of wine available in the Polish market. The results showed that the major polyphenols in chosen wines were catechin and epicatechin, the minor polyphenol was trans-resveratrol. The use of UPLC system allowed a shorter run time of up to six times in comparison with the conventional HPLC system. Total polyphenols were analyzed according to the Folin-Ciocalteu method using gallic acid as a standard and the results were presented as gallic acid equivalents. The wines were also analyzed for anthocyanins content using malvidin-3,5-diglucoside as a reference material in spectrophotometric analysis. 相似文献
503.
Marek Markowski Katarzyna Majewska Dariusz Kwiatkowski Mateusz Malkowski Grzegorz Burdylo 《International Journal of Food Properties》2013,16(4):890-903
The properties of grain of Mauritia and Prestige barley varieties were determined for moisture content of 12.5 and 15.5% wet basis. Broad variations were observed in the relationship between the moisture content of grain, its variety, and the geometric properties of barley. Most of the geometric properties of barley were dependent on both the cultivar studied and the moisture content of grain, while selected characteristics were dependent on moisture content of grain or barley cultivar only. The values of displacement, force and energy required for kernel rapture were lower for Mauritia variety than Prestige variety and were not dependent on the moisture content of grain. 相似文献
504.
Grzegorz Zatryb Artur Podhorodecki Jan Misiewicz Julien Cardin Fabrice Gourbilleau 《Nanoscale research letters》2013,8(1):40
Abstract
Silicon nanocrystals embedded in a silicon oxide matrix were deposited by radio frequency reactive magnetron sputtering. By means of Raman spectroscopy, we have found that a compressive stress is exerted on the silicon nanocrystal cores. The stress varies as a function of silicon concentration in the silicon-rich silicon oxide layers varies, which can be attributed to changes of nanocrystal environment. By conducting the Fourier transform infrared absorption experiments, we have correlated the stresses exerted on the nanocrystal core to the degree of matrix structural order.PACS
78.67.Bf, 78.67.Pt, 73.63.Bd, 78.47.D, 74.25.Nd 相似文献505.
ABSTRACTIn this work, the influence of various volume fractions of the crystalline phase in an amorphous matrix of Mg67Zn29Ca4 alloys was investigated for its corrosion resistance for biodegradable applications. An amorphous Mg67Zn29Ca4 alloy was successfully fabricated using melt casting into a copper mould. Then, to obtain different ratios of the crystalline phase in an amorphous matrix, the obtained amorphous rods with 3?mm diameters were annealed at 190, 230, 250, and 400°C. The volume fraction of the crystalline phase was measured by X-ray diffraction, and the microstructures of the obtained alloys were determined based on scanning electron microscopy images. Electrochemical testing was conducted in simulated body fluid at 37°C. This report shows that the ratio of the volume fractions of amorphous and crystalline phases in alloy microstructures strongly influences their corrosion behaviours. The alloy with a fully amorphous structure was the most resistive in the analysed media. 相似文献
506.
Grzegorz Wołkowycki 《传热工程》2013,34(6):591-602
This paper presents experimental results on the effectiveness of regenerators working integrally with an open hearth glass furnace. The presented data refer to two apparatus of identical size and geometry arranged in parallel but operating in a one-period-shifted mode. The effectiveness figures with corresponding uncertainties for each unit have been determined by making use of experimental data accounting for both heating and cooling periods. For the heating period the effectiveness is bound within the range 0.8795 ± 0.0683 to 0.9272 ± 0.0715. Considering those for the cooling period the effectiveness holds 0.9142 ± 0.0305 to 0.9499 ± 0.0329, shown to be accompanied by a bit lower uncertainty. Due to the difference in effectiveness, averaging was applied to calculate mean effectiveness value measured as weighted based on the uncertainties for both periods. As the result, the final averaged effectiveness of the investigated regenerators was found to be within the ranges of 0.9153 ± 0.0278 to 0.9367 ± 0.0296. 相似文献
507.
Grzegorz Kondrak 《Computers and the Humanities》2003,37(3):273-291
The computation of the optimal phonetic alignment andthe phonetic similarity between wordsis an important step in many applications in computational phonology,including dialectometry.After discussing several related algorithms,I present a novel approach to the problem that employsa scoring scheme for computing phonetic similarity between phonetic segmentson the basis of multivalued articulatory phonetic features.The scheme incorporates the key concept of feature salience,which is necessary to properly balance the importance of various features.The new algorithm combines several techniquesdeveloped for sequence comparison:an extended set of edit operations,local and semiglobal modes of alignment,and the capability of retrieving a set of near-optimal alignments.On a set of 82 cognate pairs,it performs better than comparable algorithms reported in the literature. 相似文献
508.
We consider the problem of waking up n processors in a completely broadcast system. We analyze this problem in both globally and locally synchronous models, with or without n being known to the processors and with or without labeling of the processors. The main question we answer is: how fast we can wake up all the processors with probability 1 - ε in each of these eight models? In [12] a logarithmic waking algorithm for the strongest set of assumptions is described, while for weaker models only linear and quadratic algorithms were obtained. We prove that in the weakest model (local synchronization, no knowledge of n or labeling) the best waking time is O(n/log n). We also show logarithmic or polylogarithmic probabilistic waking algorithms for all stronger models, which in some cases gives an exponential improvement over previous results. 相似文献
509.
W?adyslaw Knabe JarosW?aw Przew?ócki Grzegorz Ró?yński 《Probabilistic Engineering Mechanics》1998,13(3):147-167
The paper deals with the modelling of the soil medium as a random field. The necessity of using local random averages in numerical and analytical stochastic calculations are the main interest. The paper concentrates on linear elements and on the calculation of the variances and covariances of local random variables averaged over these elements. Several equations are derived by analytical integration, both for isotropic and anisotropic random fields. These should be useful for calculation, analysis and a better understanding of the influence of the geometry of elements and the value of parameters of random fields on the covariances of local averages. 相似文献
510.
The aim of this paper is to develop a formal theory of Mizar types. The examples are extracted from Mizar Mathematical Library (MML), some of them are simplified or presented in a bit different way. The presented theory is an approach to the structure of Mizar types as a sup-semilattice with widening (subtyping) relation as the order. It is an abstraction from the existing implementation of the Mizar verifier by Andrzej Trybulec and Czesław Byliński. The theory describes the structure of types of the base fragment of Mizar language. 相似文献