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141.
Ben‐Hur Ramos Ferreira Gonçalves Grazielly de Jesus Silva Silvania Farias Oliveira Pontes Rafael da Costa Ilhéu Fontan Antonio Silvio do Egito Sibelli Passini Barbosa Ferrão 《International Journal of Food Science & Technology》2016,51(7):1586-1593
Electrophoretic and chromatographic techniques were used to determine water‐soluble peptide profiles aiming to identify the adulteration of buffalo milk mozzarella cheese by the addition of cow's milk. Thus, cheeses were produced with contents of cow's milk varying from 0% to 100%, and the peptides extracted after production and after 20 days of refrigeration. Polyacrylamide gel electrophoresis under denaturing conditions in the presence of sodium dodecyl sulphate (SDS‐PAGE) identified a potential peptide marker of exclusively bovine origin with a size of about 21 kDa for the addition of cow's milk above 30%. Reverse‐phase high‐performance liquid chromatography (RP‐HPLC) indicated the existence of two potential peptides present in higher concentrations in buffalo milk and one exclusive for cow's milk, the latter making it possible to estimate the addition of cow's milk to buffalo milk. Six commercial brands of buffalo mozzarella cheese were evaluated, and indications of adulteration found in four of them. 相似文献
142.
Rafael Cortell 《加拿大化工杂志》2012,90(5):1347-1355
This paper treats about the flow and heat transfer of a viscous incompressible fluid in a porous medium over a permeable stretching surface taking into account thermal radiation and the variation of the thermal conductivity with temperature. Analytical solutions for the stream function are obtained and two cases are studied, namely, (i) prescribed surface temperature (PST case) and (ii) prescribed heat flux (PHF case). The effects of Prandtl number, permeability, suction/blowing, variable thermal conductivity, thermal radiation and surface temperature parameters on heat‐transfer characteristics are shown through tables and graphs and discussed. Ce document concerne l´écoulement et le transfer de chaleur dans le cas d´un fluide visqueux incompressible dans un milieu poreux sur une poreux surface s´étendant en tenant compte de la radiation thermique et de la conductivité thermodépendante. Les solutions analytiques pour la fonction de courant sont obtenus et deux conditions à la frontière pour la tempèrature et le flux de chaleur sont apliquées: (i) predicted surface tempèrature (PST) et (ii) le flux de chaleur predicted (PHF). Les effects du nombre de Prandtl, perméabilité, succion/soufflage, conductivité thermodépendante, radiation thermique et de la surface tempèrature sur le transfer de chaleur sont indiqués dans des tableaux et des graphiques, puis sont discutés. © 2011 Canadian Society for Chemical Engineering 相似文献
143.
In this paper, we study the use of PROMETHEE outranking methods for portfolio selection problems. Starting from a new formulation of the PROMETHEE V method, we develop several alternative approaches based on the concepts of boundary portfolios and c-optimal portfolios. The proposed methods are compared in an extensive computational study. Results of these experiments show that methods based on the concept of c-optimal portfolios provide a good approximation to the (often computationally untractable) PROMETHEE ranking of all portfolios, while requiring only small computational effort even for large problems. For smaller problems, a PROMETHEE ranking of all boundary portfolios can be performed and provides a close approximation of the total ranking. 相似文献
144.
Selecting the most appropriate heuristic for solving a specific problem is not easy, for many reasons. This article focuses on one of these reasons: traditionally, the solution search process has operated in a given manner regardless of the specific problem being solved, and the process has been the same regardless of the size, complexity and domain of the problem. To cope with this situation, search processes should mould the search into areas of the search space that are meaningful for the problem. This article builds on previous work in the development of a multi-agent paradigm using techniques derived from knowledge discovery (data-mining techniques) on databases of so-far visited solutions. The aim is to improve the search mechanisms, increase computational efficiency and use rules to enrich the formulation of optimization problems, while reducing the search space and catering to realistic problems. 相似文献
145.
146.
Vizguerra-Morales Pablo Vázquez-Castillo José Antonio Romero-Toledo Rafael Aguilera-Alvarado Alberto Florentino Ponce-Ortega José María 《Clean Technologies and Environmental Policy》2016,18(5):1599-1609
Clean Technologies and Environmental Policy - This paper presents an optimization formulation and a computational fluid dynamic study for a new proposal of a rustic oven that uses natural gas... 相似文献
147.
Encapsulationof lycopene from watermelon in calcium‐alginate microparticles using an optimised inverse‐gelation method by response surface methodology 下载免费PDF全文
Giovana B. Celli Alyne G. Teixeira Tamunoemi G. Duke Marianne Su‐Ling Brooks 《International Journal of Food Science & Technology》2016,51(6):1523-1529
Lycopene exhibits strong antioxidant activity due to its unsaturated molecular bonds, which also contributes to its susceptibility for degradation. Encapsulation techniques can reduce lycopene degradation, increasing its potential applications in functional foods and nutraceuticals. The objective of this study was to optimise the encapsulation of lycopene from watermelon in alginate microparticles using the inverse gelation method. Box–Behnken design was used for the optimisation of three variables: concentrations of alginate (w/v %) and CaCl2 (g L?1), and gelation time (min). Two types of alginate were investigated (low viscosity and high viscosity) and optimised separately using encapsulation efficiency and loading capacity as responses. Results indicated that the models had a good fit to the experimental data and the optimal conditions varied depending on the type of alginate. In general, particles prepared with low‐viscosity alginate exhibited higher encapsulation efficiency and loading capacity and could be used for further research. 相似文献
148.
René Marcelino Abritta Teixeira Toshihiko Yamasaki Kiyoharu Aizawa 《Multimedia Tools and Applications》2012,61(1):21-49
Affective analysis of video content has greatly increased the possibilities of the way we perceive and deal with media. Different kinds of strategies have been tried, but results are still opened to improvements. Most of the problems come from the lack of standardized test set and real affective models. In order to cope with these issues, in this paper we describe the results of our work on the determination of affective models for evaluation of video clips using audiovisual low-level features. The affective models were developed following two classes of psychological theories of affect: categorial and dimensional. The affective models were created from real data, acquired through a series of user experiments. They reflect the affective state of a viewer after watching a certain scene from a movie. We evaluate the detection of Pleasure, Arousal and Dominance coefficients as well as the detection rate of six affective categories. For this end, two Bayesian network topologies are used, a Hidden Markov Model and an Autoregressive Hidden Markov Model. The measurements were done using audio-only models, video-only models and fused models. Fusion is done using two different methods, a Decision Level Fusion and Feature Level Fusion. All tests were conducted using localized affective models, both categorial and dimensional. Results are presented in terms of detection rate and accuracy for affective families, affective dimensions and probabilistic networks. Arousal was the best detected dimension, followed by dominance and pleasure. 相似文献
149.
Rafael Mattos Deus Rosane Aparecida Gomes Battistelle Gustavo Henrique Ribeiro Silva 《Clean Technologies and Environmental Policy》2017,19(1):205-214
As achieving Brazil’s National Policy on Solid Waste-based goals effectively is not simple, there are alternatives such as intermunicipal cooperation by consortium or privatization. Therefore, this study aimed to evaluate the Greenhouse Gas emissions and energy use of six scenarios in two landfills contexts (private and consortium) for small municipalities (less than 100,000 inhabitants as per Brazilian standards) located in São Paulo, Brazil. Through the technique of scenario building and method of Waste Reduction Model was possible to obtain the total energy, the amount of carbon dioxide equivalent (CO2E) and carbon equivalent (CE) emissions. The best scenario integrates composting and recycling, reducing 72 % for CO2E and CE emissions, and saving about 410 % in energy. The landfill consortium will only take advantage, if the location is the most ideal as far as possible. Small municipalities that do not dispose their waste in landfills compatible with regulatory standards may seek for intermunicipal cooperation and adopt integrated waste-management programmes to reduce their environmental impacts. 相似文献
150.
Oscar L. Ramos Ricardo N. Pereira Artur Martins Rui Rodrigues Clara Fuciños José A. Teixeira 《Critical reviews in food science and nutrition》2017,57(7):1377-1393
Whey proteins are widely used as nutritional and functional ingredients in formulated foods because they are relatively inexpensive, generally recognized as safe (GRAS) ingredient, and possess important biological, physical, and chemical functionalities. Denaturation and aggregation behavior of these proteins is of particular relevance toward manufacture of novel nanostructures with a number of potential uses. When these processes are properly engineered and controlled, whey proteins may be formed into nanohydrogels, nanofibrils, or nanotubes and be used as carrier of bioactive compounds. This review intends to discuss the latest understandings of nanoscale phenomena of whey protein denaturation and aggregation that may contribute for the design of protein nanostructures. Whey protein aggregation and gelation pathways under different processing and environmental conditions such as microwave heating, high voltage, and moderate electrical fields, high pressure, temperature, pH, and ionic strength were critically assessed. Moreover, several potential applications of nanohydrogels, nanofibrils, and nanotubes for controlled release of nutraceutical compounds (e.g. probiotics, vitamins, antioxidants, and peptides) were also included. Controlling the size of protein networks at nanoscale through application of different processing and environmental conditions can open perspectives for development of nanostructures with new or improved functionalities for incorporation and release of nutraceuticals in food matrices. 相似文献