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81.
Ana Paula Rodrigues Brasil Sebastio Tavares de Rezende Maria do Carmo Gouveia Pelúzio Valria Monteze Guimares 《Food chemistry》2010,118(2):251-255
The objectives of this work were to establish a safe and economically viable process for the removal of raffinose oligosaccharides (RO) from soy flour and compare the effects of RO elimination from diets with regard to nutritional parameters by testing in Wistar rats. Debaryomyces hansenii UFV-1 was cultivated in suspension of defatted soy flour (1:10 w/v). An increase in α-galactosidase activity was observed in the medium, with a consequent decrease in the RO concentration. A total reduction of RO was achieved at 36 h of incubation. The diet containing soy flour free of RO presented higher digestibility, 91.28%, in relation to the diet containing soy flour with RO, 87.14%. However, the removal of the oligosaccharides from the diet did not promote a significant improvement in the values of weight gain, and other nutritional parameters tested on rats, during the experimental period of 14 days. 相似文献
82.
D. Brandt M. Asai P. L. Brink B. Cabrera E. do Couto?e?Silva M. Kelsey S. W. Leman K. McArthy R. Resch D. Wright E. Figueroa-Feliciano 《Journal of Low Temperature Physics》2012,167(3-4):485-490
There is a growing interest in cryogenic calorimeters with macroscopic absorbers for applications such as dark matter direct detection and rare event search experiments. The physics of energy transport in calorimeters with absorber masses exceeding several grams is made complex by the anisotropic nature of the absorber crystals as well as the changing mean free paths as phonons decay to progressively lower energies. We present a Monte Carlo model capable of simulating anisotropic phonon transport in cryogenic crystals. We have initiated the validation process and discuss the level of agreement between our simulation and experimental results reported in the literature, focusing on heat pulse propagation in germanium. The simulation framework is implemented using Geant4, a toolkit originally developed for high-energy physics Monte Carlo simulations. Geant4 has also been used for nuclear and accelerator physics, and applications in medical and space sciences. We believe that our current work may open up new avenues for applications in material science and condensed matter physics. 相似文献
83.
84.
Diogo C. Garcia Anésio L.F. Filho Marco A.G. Oliveira Onivaldo A. Fernandes Francisco A. do Nascimento 《Electric Power Systems Research》2009
Among a series of parameters, power quality studies are concerned with voltage unbalances, which represent the voltage magnitude and phase deviation from nominal values. In order to determine the influence of the network's parameters on voltage unbalances, and to provide exact solutions to reduce or even eliminate them, the present study develops and presents two methods. First, a sensitivity analysis is used to determine the influence of each parameter, and then analytical solutions are developed in order to provide the changes needed for correction. The quantification index considered is the symmetrical components method. 相似文献
85.
In many countries, governments are pushing for the introduction of competition in the organization of public services and more broadly in public procurement. The development of public–private partnerships throughout the world is a good illustration of this trend. In order to foster competition, competitive tendering through the use of auctions is now common. Nevertheless, competition for the field must be organized. Depending on the rules of the game chosen, introducing competition for the field may or may not be successful. In this paper we investigate two alternative models for organizing local public services, namely the French and the London models of urban public transport. Few competitors and collusive behaviours, with increasing costs, characterize the French model, while the London model, as far as we have seen, exhibits better results, by using the transparency of auction procedures and the discretionary power of the regulator as two complementary instruments to foster competition and prevent anti-competitive behaviours. 相似文献
86.
87.
Scientometrics - At the Leibniz Institute for Baltic Sea Research Warnemünde (the home institute of this paper), scientists have been exploring the common denominator between microplastics and... 相似文献
88.
Colour assays: An inside look into Alentejo traditional limewash paintings and coloured lime mortars
Milene Gil Jose Aguiar Ana Seruya Rosário Veiga Luisa Carvalho Helena Vargas Jose Mirão Antonio Candeias 《Color research and application》2011,36(1):61-71
A series of colour assays were conducted taking into account old bibliographic recommendations and oral testimony regarding traditional lime painting technology from the Alentejo (South Portugal) region. The main objectives were: (a) the colorimetric analysis of paintings made with different limewash preparation methods; (b) the comparison between natural processed red and yellows ochre pigments (“home made” and from industrial origin) and synthetic iron oxides in different concentrations and lime proportions; (c) the evaluation of the colorimetric CIELAB coordinates during the lime carbonation process in coloured mortars and limewashes. The results shows that the evolution of L*, a*, and b* during the carbonation process is independent of pigment concentration and paint thickness but dependent of pigment composition and finishing technique (lime painting or coloured mortar). They also emphasize the importance of surface appearance attributes and its influence on the colorimetric parameters. © 2010 Wiley Periodicals, Inc. Col Res Appl, 36, 61–71, 2011 相似文献
89.
A recent EC directive has called for all member states to introduce legislation covering the assessment and restriction of air crew exposure to cosmic radiation. In the UK the Civil Aviation Authority, in conjunction with the Department of the Environment. Transport and the Regions issued guidelines suggesting the use of a predictive code such as CARI for this purpose. In order to validate the use of calculated route doses, an extensive programme of measurements is being carried out on long haul routes in conjunction with Virgin Atlantic Airways, using a prototype HAWK TEPC developed by Far West Technology. This programme began in January 2000 and by the end of February 2001 had resulted in the accumulation of data from 74 flights. In this paper the instrument design is discussed, together with the calibration programme. An overview of the in-flight results is also presented, including comparisons between measurements and calculations, which indicates that CARI under-predicts the route doses by approximately 20%. 相似文献
90.
U.S. Sias L. Amaral M. Behar H. Boudinov E.C. Moreira 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2006,250(1-2):178-182
In the present work we have studied the photoluminescence (PL) behavior from Si nanocrystals (NCs) as a function of the excitation power density and annealing time. The NCs were produced in a SiO2 matrix by Si implantations from room temperature (RT) up to 700 °C, followed by post-annealing in N2 atmosphere at high temperature. With this aim we have changed the excitation power density (from 2 × 10−3 W/cm2 up to 15 W/cm2) and the annealing time (from 10 min up to 15 h). The strong PL signal, which at 15 W/cm2 is composed by a single-peak structure (650–1000 nm) centered at around 780 nm, expands up to 1200 nm showing a two-peak structure when measured at 20 × 10−3 W/cm2. The peak structure located at the short wavelength side is kept at 780 nm, while the second peak, starting at around 900 nm, redshifts and increases its intensity with the implantation temperature and annealing time. The effect of the annealing time on the PL spectra behavior measured at low excitation power agrees by the first time with the Si NC growth according to quantum confinement effects. 相似文献