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51.
Vera Stepanska 《纺织导报》2006,(1):43-45
Rieter(立达)公司的BT系列气流纺纱机以生产经济性、使用灵活性和可靠性高而闻名。新型BT 923半自动气流纺纱机以卓越的性价比生产高质量气流纱。经过彻底重新设计的BT 923(图1)在半自动气流纺纱机系列中处于领先地位.使半自动气流纺纱机达到新的水平。 相似文献
52.
Driving factors of the phytoplankton functional groups in a deep Mediterranean reservoir 总被引:8,自引:0,他引:8
Vanessa Becker Luciano Caputo Rafael Marcé Joan Armengol Vera L.M. Huszar 《Water research》2010,44(11):3345-5109
The control of phytoplankton growth is mainly related to the availability of light and nutrients. Both may select phytoplankton species, but only if they occur in limiting amounts. During the last decade, the functional groups approach, based on the physiological, morphological and ecological attributes of the species, has proved to be a more efficient way to analyze seasonal changes in phytoplankton biomass. We analysed the dynamics of the phytoplankton functional groups sensu Reynolds, recognising the driving forces (light, mixing regime, and nutrients) in the Sau Reservoir, based on a one-year cycle (monthly surface-water sampling). The Sau Reservoir is a Mediterranean water-supply reservoir with a canyon-shaped basin and a clear and mixed epilimnion layer. The long stratification period and high light availability led to high phytoplankton biomass (110.8 fresh-weight mg L−1) in the epilimnion during summer. The reservoir showed P-limitation for phytoplankton growth in this period. All functional groups included one or more species (X2-Rhodomonas spp.; Y-Cryptomonas spp.; F-Oocystis lacustris; K-Aphanocapsa spp.) selected by resources, especially phosphorus. Species of Cryptomonas (group Y) dominated during the mixing period (winter season) in conditions of low light and relatively high availability of dissolved nutrients. Increases in water-column stability during spring stratification led to phytoplankton biomass increases due to the dominance of small flagellate functional groups (X2 and X3, chrysophyceans). The colonial chlorophycean O. lacustris (group F) peaked during the mid-summer stratification, when the mixed epilimnion was clearly depleted in nutrients, especially SRP. High temperature and increases in nutrient concentration during the end-summer and mid-autumn resulted in a decrease of green algae (group F) and increase of Aphanocapsa spp. (cyanobacteria, group K) and dinoflagellates (group Lo). The study also revealed the important role of physical processes in the seasonal gradient, in selecting phytoplankton functional groups, and consequently in the assessment of ecological status. The Q index (assemblage index) based on functional groups indicated the overall good ecological status of the Sau Reservoir, which varied as a function of the mixing regime. This is the first application of the Assemblage Index to a European water-supply reservoir. 相似文献
53.
54.
Nevena Krkić Branislav Šojić Vera Lazić Ljiljana Petrović Anamarija Mandić Ivana Sedej Vladimir Tomović 《Meat science》2013
The effect of a chitosan coating with added essential oil of oregano (Origanum vulgare) on lipid oxidation of dry fermented sausage (Petrovská klobása) was investigated. Fatty acid profile, aldehyde contents and sensory analysis of odor and flavor were determined after drying and during seven months of storage. 相似文献
55.
J. A. Vera 《Multibody System Dynamics》2010,23(3):263-291
In this paper, we consider the noncanonical Hamiltonian dynamics of a gyrostat in the three-body problem. By means of geometric-mechanics
methods, we study the approximate Poisson dynamics that arises when we develop the potential of the system in series of Legendre
and truncate this in an arbitrary order k. After reduction of the dynamics by means of the two symmetries of the system, the existence and number of equilibria that
we denominate of Lagrangian type in analogy with classic results on the topic, are considered. Necessary and sufficient conditions
are established for their existence in an approximate dynamics of order k, and explicit expressions of these equilibria are given; this being useful for the subsequent study of the stability of these
equilibria. The number of Lagrangian equilibria is thoroughly studied in approximate dynamics of orders zero and one. The
main result of this work indicates that the number of Lagrangian equilibria in an approximate dynamics of order k for k≥1 is independent of the order of truncation of the potential, if the gyrostat S
0 is almost spherical. In relation to the stability of these equilibria, necessary and sufficient conditions are given for
linear stability of Lagrangian equilibria when the gyrostat is almost spherical. The rotational Poisson dynamics of the gyrostat
placed at an Lagrangian equilibrium is explored and the study of nonlinear stability conditions is considered. In this way,
we generalize the classical results on equilibria of the three-body problem and many results provided by other authors using
more classical techniques for the case of rigid bodies. 相似文献
56.
Through a qualitative, critical incident research design, this study identified and defined critical incidents that cultivated a social justice orientation among counseling psychology doctoral students and professionals. Research questions included: (a) What incidents are critical in the development of a social justice orientation? (b) Of these incidents, which are most influential? (c) How do these incidents affect social justice orientation development? Thirty-six counseling psychology doctoral students and professionals, who demonstrated a commitment to social justice through scholarship and clinical practice, completed an online survey, which consisted of rank-order and open-ended items. Qualitative data were analyzed utilizing the constant comparative method. Analyses revealed five categories of critical incidents to which participants attributed their social justice orientation development. In addition, five themes were identified that categorized the ways in which critical incidents changed individuals. Analyses of rank-ordered items indicated that the categories of Exposure to Injustice and Influence of Significant Persons were most frequently ranked as the most influential critical incidents in the development of a social justice orientation. Implications of these results and future directions for education, training, and research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Cooking and texture properties of gluten‐free fettuccine processed from defatted flaxseed flour and rice flour
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Camila M. A. de Moura Manoel S. Soares Júnior Fernanda A. Fiorda Márcio Caliari Rosângela Vera Maria V. E. Grossmann 《International Journal of Food Science & Technology》2016,51(6):1495-1501
Nonconventional raw materials have been applied in gluten‐free pasta, to meet the demand of people with coeliac disease. The objective of this study was to evaluate the cooking properties and texture of pasta formulated with rice flour, defatted flaxseed flour and pregelatinised mixed flour of rice and flaxseed (80:20). For this experiment, simplex design was used. Cooking properties and texture were found within the quality limits established for this type of product. The pasta with the most desirable properties (short optimum cooking time (OCT), less solid loss (SL) and intermediate mass increase (MI)) was that one formulated with 43 g 100 g?1 of pregelatinised flour, 47 g 100 g?1 of rice flour and 10 g 100 g?1 of defatted flaxseed flour. This formulation can be characterised as a food rich in dietary fibre and of high nutritional value. 相似文献
58.
Sustainable recovery of grape skins for use in an apple beverage with antiglycation properties
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Vera Lavelli Pedapati S.C. Sri Harsha Maria Piochi Luisa Torri 《International Journal of Food Science & Technology》2017,52(1):108-117
An apple puree formulated with red grape skins was developed on pilot scale as a new beverage with antiglycation properties. The addition level of grape skins was selected by a liking test with 70 consumers. The selected formulation was a fibre‐rich source and delivered grape anthocyanins, flavonols and flavanols resulting in ~ twofold higher antiglycation activity than the apple puree. Pasteurisation (3‐D in the target microorganism Alicyclobacillus acidoterrestris) did not affect the antiglycation activity, which decreased by 30% upon sterilisation. Storage for 1 month in the temperature range 15–35 °C affected the contents of anthocyanins, monomeric, dimeric and oligomeric flavanols, while chlorogenic acid, flavonols and dihydrochalcones were stable. About 90% antiglycation activity was retained after one‐month storage at 15 °C. The use of red grape skin as ingredient could represent an opportunity for the apple processing industry to develop a value‐added product. 相似文献
59.
Khoruzhaya Vera G. Martsenyuk Petr S. Meleshevich Konstantin A. Velikanova Tamara Ya. 《Powder Metallurgy and Metal Ceramics》2002,41(5-6):278-283
The reaction of components of the Si — Al — O — N — Ti system in its elements Si 3N4 — AlN, TiN — AlN, and Al 2O 3 — AlN was investigated by differential thermal and x-ray diffraction analysis. It was established that upon hot pressing mixtures of Si3N 4 and AlN (up to 1950°C) free silicon is formed by the decomposition of Si 3N4, which reacts with oxygen present as an impurity to form SiO. When TiN reacts with AlN a phase with the spinel structure (Al23O 27N 5), which can form only in the presence of excess oxygen, appears in addition to the initial components. Spinel is also produced by the reaction of Al 2O3 with AlN. In this case a eutectic between Al 23O27N5 and Al2O3 is observed. 相似文献
60.
Soft errors are an important challenge in contemporary microprocessors. Particle hits on the components of a processor are expected to create an increasing number of transient errors with each new microprocessor generation. In this paper we propose simple mechanisms that effectively reduce the vulnerability to soft errors In a processor. Our designs are generally motivated by the fact that many of the produced and consumed values in the processors are narrow and their upper order bits are meaningless. Soft errors canted by any particle strike to these higher order bits can be avoided by simply identifying these narrow values. Alternatively soft errors can be detected or corrected on the narrow values by replicating the vulnerable portion of the value inside the storage space provided for the upper order bits of these operands. We offer a variety of schemes that make use of narrow values and analyze their efficiency in reducing soft error vulnerability of level-1 data cache of the processor 相似文献