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41.
Ana Faria Diogo Pestana Rosário Monteiro Joana Oliveira Victor de Freitas Isabel Azevedo Conceição Calhau Nuno Mateus 《Food chemistry》2008
The aim of the present study was to investigate the influence of an anthocyanin extract (extract I), and two other derivative extracts (extracts II and III), which are being developed aiming to be further applied in the food industry, on intestinal uptake of organic cations. For this purpose, the effect of these compounds on 3H-MPP+ uptake was evaluated in Caco-2 cells (an enterocyte-like cell line derived from a human colonic adenocarcinoma). 相似文献
42.
Invented and developed at LLNL (Lawrence Livermore National Laboratory), this inexpensive and highly sensitive radar system produces and samples extremely short pulses of energy. This novel technology is finding dozens of new uses in Laboratory programs and in sensor devices for homes, automobiles, factories, and hospitals. We have invented and patented a fundamentally different type of compact, low-power radar system called micropower impulse radar (MIR), which is orders of magnitude less expensive to produce than other conventional radars. Unlike conventional radar, which sends out continuous waves in bursts, MIR uses very short electromagnetic pulses and can detect objects at much shorter range. The new technology has become LLNL's fastest growing technology transfer activity primarily because of its low cost and extraordinary range of applications 相似文献
43.
Frank S
S Rogerson Zelia Azevedo Nlia Fortunato Victor A
P de Freitas 《Journal of the science of food and agriculture》2002,82(11):1287-1292
1,3‐Dimethoxybenzene was identified by GC–O, GC–MS and Kovats indices (polar Supelcowax, 1709; non‐polar Rtx‐5MS, 1158) as a new volatile component of port wine. Sensory evaluation described this compound as having a sweet medicinal odour with hazelnut, resinous and woody notes. Respective threshold limits in model wine and port wine were 21 and 47 µg l?1. Quantitative analysis by GC–MS, using a selected characteristic ion (m/z 138), indicated that young port wines from the 1998 vintage contained up to 3 µg l?1 whereas ports from the 1999 vintage contained up to 20 µg l?1. © 2002 Society of Chemical Industry 相似文献
44.
45.
Ana Karina Couto Campos Ângela Maria Soares Cardonha Liana Bacurau Galvão Pinheiro Neide Rocha Ferreira Paulo Roberto Medeiros de Azevedo Tânia Lúcia Montenegro Stamford 《Food Control》2009,20(9):807-810
The aim of this study was to assess the hygiene practices of food handlers in municipal schools of Natal, Brazil, where 27 public schools were evaluated, using a checklist and microbiological analysis of hands. It was found that 74.1% of the handlers did not receive periodic training, 51.9% did not undergo annual health examinations and 100% did not practice proper hand hygiene, a situation that reflected significantly (p < 0.05) in hand contamination, in which fecal coliforms were detected on 55.6% of the hands analyzed. It was concluded that the schools studied did not have appropriate hygienic conditions, suggesting the need for interventions that ensure the quality of school food served to the children. 相似文献
46.
R. L. Rodríguez-Suárez S. M. Rezende A. Azevedo F. M. Aguiar 《Journal of Superconductivity and Novel Magnetism》2010,23(1):33-35
Here we present a calculation for the linewidth of the spin-wave that is generated when a spin valve nanostructure is traversed
by a high-density spin-polarized direct current. In this case, the magnetization excitations are considered to be standing
spin-wave modes interacting through the four-magnon processes. We obtain an analytic expression for the effective nonlinear
dissipation rate of a magnetic spin-torque nano-oscillator, taking into account a nonlinear phenomenological model of magnetic
dissipation and the natural nonlinear contributions due to the demagnetizing fields. The calculation is applied for the general
case of the external magnetic field applied in an arbitrary direction. 相似文献
47.
Maria Francesca Riccio Sérgio A. Saraiva Lygia Azevedo Marques Rosana Alberici Renato Haddad Jens C. Moller Marcos N. Eberlin Rodrigo Ramos Catharino 《European Journal of Lipid Science and Technology》2010,112(4):434-438
Easy ambient sonic spray ionization (EASI), a novel desorption/ionization technique for ambient mass spectrometry analysis, is shown to permit the characterization of different types of vegetable and animal fats. The taxonomic markers of the oils, mainly fatty acids and phenols, are extracted with methanol/water (1:1) solution and made alkaline with NH4OH, then placed and dried on the surface of a glass tip and directly analyzed by EASI‐MS in the negative‐ion mode. EASI provides a supersonic cloud of charged droplets that causes efficient desorption and ionization of the oil markers directly from the surface of the glass tip. As proof‐of‐principle cases, EASI(?)‐MS was applied to genuine samples of olive oil, hazelnut oil, soybean oil, grape seed oil, canola oil, butter, and lard. Characteristic metabolomics EASI(?)‐MS profiles of fatty acids and eventually phenols were obtained. 相似文献
48.
C.R.F. Azevedo 《Engineering Failure Analysis》2011,18(8):1943-1962
The growing understanding of the link between carbon emissions and global warming has been promoting a discussion on the environmental and safety viability of nuclear power generation. Current open fuel cycle reactors, however, result in low energy efficiency and produce large volumes of nuclear waste. More advanced nuclear reactors, which are currently under investigation, are expected to allow more efficient and safer use of nuclear energy. In all these cases, the fuel cladding is the most important safety barrier in fission nuclear reactors, as it restrains most of the radioactive fission products within its volume. The selection of fuel cladding material is based on many design constraints, such as neutron absorption cross section, service temperature, mechanical strength, toughness, neutron radiation resistance, thermal expansion, thermal conductivity, and chemical compatibility. The present paper reviews the selection of nuclear fuel cladding materials since the early reactors, illustrating some of the main failure modes and briefly discussing the challenges facing the development of fuel cladding materials for generation IV reactors. 相似文献
49.
Orsino Oliveira Filho Jose Antonio Cardoso Darcy Ramalho de Mello Rogerio Magalhges de Azevedo Sylvia G Carvalho 《高电压技术》2011,37(11):2772-2779
Studies based on AC high voltage tests have been done at Cepel to investigate the performance of 800 kV bushar insulators under heavy wetting conditions. Insulators were tested which are now used on si... 相似文献
50.
Francisco A. P. Costa Edson M. dos Reis Júlio C. R. Azevedo Jorge Nozaki 《Solar Energy》2004,77(1):29-35
The photooxidation of textile dyes Yellow Procion H-4R, Bright Blue Remazol (blue reagent-19), Red Procion H-E7B, and the mixture of the two last dyes were investigated. The efficiency of photooxidation were compared using hydrogen peroxide (30%) as a bleaching reagent, solar and ultraviolet radiation, common glass borosilicate, quartz assay tubes, and no solid catalysts. The colour of blue dye and a mixture of blue and red dyes were almost completely removed after 3 h, either by solar or ultraviolet radiation. The best results of colour removal (93%) for the red and yellow dyestuffs were obtained only after 6 h, using quartz tubes, hydrogen peroxide and ultraviolet radiation. Using non-parametrical statistical tests (χ2), the treatment showed significant differences among the processes investigated (P<0.01). 相似文献