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971.
972.
Graça Almeida Fernando Melício Hugo Biscaia Carlos Chastre José Manuel Fonseca 《Computer-Aided Civil and Infrastructure Engineering》2016,31(4):292-304
Measurements in civil engineering load tests usually require considerable time and complex procedures. Therefore, measurements are usually constrained by the number of sensors resulting in a restricted monitored area. Image processing analysis is an alternative way that enables the measurement of the complete area of interest with a simple and effective setup. In this article photo sequences taken during load displacement tests were captured by a digital camera and processed with image correlation algorithms. Three different image processing algorithms were used with real images taken from tests using specimens of PVC and Plexiglas. The data obtained from the image processing algorithms were also compared with the data from physical sensors. A complete displacement and strain map were obtained. Results show that the accuracy of the measurements obtained by photogrammetry is equivalent to that from the physical sensors but with much less equipment and fewer setup requirements. 相似文献
973.
974.
975.
M. F. AL-Naday R. C. Almeida Jr. K. M. Guild M. J. Reed 《Photonic Network Communications》2012,24(2):132-137
This paper presents the design of a hardware accelerated forwarding architecture for processing packets that are labelled with a Bloom Filter (BF)-based header. The architecture consists of a conventional broadcast-and-select all-optical switching fabric, composed of Semiconductor Optical Amplifiers (SOAs), and a hardware-based Serial Processing Unit (SPU) that uses an on-the-fly processing mechanism to forward optical packets. The proposed SPU avoids the use of memory units and uses a small number of logic gates that facilitate a straightforward all-optical implementation using photonic logic gates. The SPU also supports flexible wavelength multicasting by allowing each incoming wavelength to be forwarded to any number of output ports. Contention resolution is provided by the introduction of an Optical Delay Line (ODL) that provides a single-packet optical buffer if the output channel is occupied. 相似文献
976.
Melina Maynara Carvalho de Almeida Cristhian Rafael Lopes Francisco Anielle de Oliveira Sabrina Silva de Campos Ana Paula Bilck Renata Hernandez Barros Fuchs Odinei Hess Gonçalves Patrícia Velderrama Aziza Kamal Genena Fernanda Vitória Leimann 《Food and Bioprocess Technology》2018,11(5):926-939
Encapsulation of chia oil might protect omega-3 and omega-6 from lipid oxidation when producing baked foods. However, the actual gain in stability given by chia oil must be determined. In this work, chia oil or chia oil-loaded microparticles were added to a cookie formulation in order to evaluate the ability of the microcapsules in protecting chia oil from deterioration. Texture, color, water sorption isotherms, and sensorial properties were also evaluated. A hot homogenization technique was used with carnauba wax as an encapsulant, and the freeze-dried microparticles were incorporated into the cookie dough. Principal component analyses were carried out to evaluate lipid oxidation using the medium infrared spectra of the lipid fraction extracted from the baked cookies. It was found that the microencapsulated chia oil was better protected from oxidative deterioration during baking compared to the sample containing non-encapsulated chia oil. Textural analysis showed that chia oil (free and microencapsulated) acted as a coating on the wheat flour particles. Control cookies (no chia oil loaded) presented a more hydrophilic character. In the case of oil-loaded samples (free and microencapsulated), the isosteric heat of sorption behavior indicated an initial swelling step of the food polymers, resulting in the exposure of sorption sites of higher binding energies not previously available, and that this is because of the wheat particles being covered by the chia oil and the solid lipid microparticles. Furthermore, food acceptability did not change when the oil-loaded microparticles were added to the cookie formulation. 相似文献
977.
Mauro Almeida Mariana Magalhães Francisco Veiga Ana Figueiras 《Journal of Polymer Research》2018,25(1):31
Research for new therapies to treat diseases like cancer, it is one of the focus of Health Sciences. Nowadays, the available therapeutic strategies have in many cases limitations and undesired side effects, which shows a need to find new therapies with a higher efficacy. In this regard, over the past few years, poloxamers and poloxamines have been gaining more attention in the pharmaceutical field, mainly due to their advantages as potential nanosystems. Therefore, poloxamers and poloxamines are amphiphilic block of copolymers constituted by PEO units, poly(ethylene oxide), and PPO units, poly(propylene oxide), presenting the capability to self-assembly in micellar structures in aqueous medium forming polymeric micelles, which improve theirs potential as drug and genetic material nanocarriers. Thereby, in order to create new alternative treatments for current pathologies, like cancer, alterations in the poloxamines and poloxamers, the combination of these with other polymers and the conjugation with ligands are being introduced as a viable option to allow the combination of therapies, such as the simultaneous delivery of a gene and a drug in the same system. These intelligent stimuli-sensitive systems, with well-defined structures and functionalities, make possible the development of a safe, specific and effective therapeutic strategy. Thus, this article intends to review several aspects of poloxamines and poloxamers concerning their general properties and their applications in drug and gene delivery. Also, are reviewed the preparation and characterization techniques of polymeric micelles with a focus in micelleplexes which can be used as a simultaneous drug and nucleic acid carrier. 相似文献
978.
The effects of enzymatic interesterification on the physical-chemical properties of blends of lard and soybean oil 总被引:3,自引:0,他引:3
Roberta C. Silva Tatyane P. Poltronieri Denise B. de Almeida Renato Grimaldi 《LWT》2009,42(7):1275-612
The main goal of the present research effort was to evaluate the physical-chemical properties of blends of lard and soybean oil following enzymatic interesterification catalyzed by an immobilized lipase from Thermomyces lanuginosa (Lipozyme™ TL IM). Lipase-catalyzed interesterification produced new triacylglycerols that changed the physical-chemical properties of the fat blends under study. Solid fat content (31.3 vs 31.5 g/100 g), consistency (104.7 vs 167.6 kPa), crystallized area (0.6 vs 11.8) and softening point (31.8 vs 32.2 °C) of lard increased after interesterification, and this was mostly due to the increase of SSS (saturated) + SSU (disaturated-monounsaturated) triacylglycerols. These contents (SSU + SSS) increased in lard after interesterification from 42.9 to 46.7 g/100 g. The interesterified blends exhibited lower values for the physical properties when compared with their counterparts before enzymatic interesterification. The interesterification of blends of lard with soybean oil increased the amounts of UUU (triunsaturated) and SSS triacylglycerols and reduced the amounts of UUS (diunsaturated-monosaturated) triacylglycerols. The interesterified blends of lard and soybean oil demonstrated physical properties and chemical composition similar to human milk fat and they could be used for the production of a human milk fat substitute. 相似文献
979.
Considering the occurrence of rice contamination by mycotoxins and the increase in rice consumption, the present work had the objective of assessing the migration of mycotoxins into the starchy endosperm during the parboiling process, as to propose conditions that provide lower contamination levels. The newly harvested rice grain sample was examined for the natural occurrence of mycotoxins (aflatoxin B1, aflatoxin B2, deoxynivalenol, ochratoxin A, and zearalenone); only the presence of aflatoxin B1 was found (17 ng/g). The samples were then artificially contaminated with deoxynivalenol and zearalenone, and the parboiling process was conducted according to a 23 factorial planning with central point, having as variables the contamination level deoxynivalenol 720, 1440, and 2160 ng/g, and zearalenone 476, 952, and 1428 ng/g the soaking time (4, 5, and 6 h) and autoclave time (15, 22.5, and 30 min). Mycotoxins aflatoxin B1 (AFA B1), deoxynivalenol (DON), and zearalenone (ZEA) were confirmed and determined through gas chromatography. Findings showed a lower migration trend for AFA B1 under 6 h of soaking and 30 min of autoclaving, for DON under 6 h of soaking regardless of the autoclaving time, and for ZEA under 4 h of soaking and 15 min of autoclaving. This information can contribute to the choice of process parameters that limit the migration of these mycotoxins if they happen in the raw material. 相似文献
980.
José Geraldo de Melo Furtado George Cassani Gatti Eduardo Torres Serra Silvio Carlos Anibal de Almeida 《International Journal of Hydrogen Energy》2010
Power systems based on fuel cells have been considered for residential and commercial applications in energy Distributed Generation (DG) markets. In this work we present an experimental analysis of a power generation system formed by a 5 kW proton exchange membrane fuel cell (PEMFC) unit and a natural gas reformer (fuel processor) for hydrogen production. The performance analysis developed simultaneously the energy and economic viewpoints and enabled the determination of the best technical and economic conditions of this energy generation power plant, and the best operating strategies, enabling the optimization of the overall performance of the stationary cogeneration fuel cell unit. It was determined the electrical performance of the cogeneration system in function of the design and operational power plant parameters. Additionally, it was verified the influence of the activation conditions of the fuel cell electrocatalytic system on the system performance. It also appeared that the use of hydrogen produced from the natural gas catalytic reforming provided the system operation in excellent electrothermal stability conditions resulting in increase of the energy conversion efficiency and of the economicity of the cogeneration power plant. 相似文献