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71.
72.
Daniele da Silva Bastos Maria do Pilar Gonçalves Cristina Tristão de Andrade Kátia Gomes de Lima Araújo Maria Helena Miguez da Rocha Leão 《Food and Bioproducts Processing》2012,90(4):683-692
The aim of this work was to obtain a new stable food product from cashew apple juice encapsulated by spray-drying technique using chitosan–whey protein isolate systems. The materials were evaluated according to their physicochemical stability during storage at different conditions and characterized with respect to their particle size distribution and structure. Encapsulated commercial and natural juices showed homogenous and unimodal particle size distribution with diameters ranging from 0.2 to 5.0 μm and from 0.2 to 40.0 μm, respectively. Both juices demonstrated higher physicochemical stability for vitamin C and color measurements than their respective non-encapsulated juices. X-ray diffractograms evidenced that the powder juices after the 140th day of storage were still in amorphous state. These results indicate that the new product was effective in protecting sensitive compounds present in the food matrix and it was also able to remain stable throughout the study period. 相似文献
73.
A feasibility study of Lactobacillus plantarum in fruit powders after processing and storage
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Sandra Borges Joana Barbosa Joana Silva Ana M. Gomes Manuela Pintado Cristina L. M. Silva Alcina M. M. B. Morais Paula Teixeira 《International Journal of Food Science & Technology》2016,51(2):381-388
The aim of this study was to develop fruit powders (apple, banana and strawberry) enriched with a probiotic strain (Lactobacillus plantarum 299v). Two methodologies were proposed: (i) drying of the fruit with probiotic culture incorporated (by convection) or (ii) drying of fruit (by convection) and addition of spray‐dried probiotic culture. In the first methodology, processing caused a notable reduction in probiotic viable counts in apple, but this reduction was lower during drying of banana and strawberry. A large reduction in viable cells was also recorded during storage. In the second methodology, the survival of L. plantarum 299v was considerably higher during spray‐drying, and fruit powders with a microbial content suitable for a probiotic food (108–109 cfu g?1) were obtained. The fruit powders incorporating L. plantarum 299v can be stored at 4 °C or at room temperature, for at least 3 months. This preliminary study demonstrated that fruit powders are good carriers of probiotic cultures, but the techniques used to produce them should be carefully considered. 相似文献
74.
75.
Joana V. Barbosa Fernanda Oliveira Jorge Moniz Fern?o D. Magalh?es Margarida M. S. M. Bastos 《Journal of the American Oil Chemists' Society》2012,89(12):2215-2226
This work evaluated the use of allyl fatty acid esters derived from vegetable oil (palmitic acid, soybean and sunflower oils) as reactive coalescing agents in a waterborne latex system. Allyl fatty acid derivatives (AFAD) from vegetable oils were synthesized by two different processes. The synthesis was monitored by IR-spectroscopy and the final product characterized by FT-IR, GC–MS, 1H and 13C NMR. The presence of conjugated double bonds in the aliphatic chain was confirmed, which is a determinant for the proposed autoxidative latexes drying mechanism. Each of the AFAD were subsequently added to a standard acrylic emulsion, in order to study its potential as reactive coalescing agent. The minimum film-forming temperature (MFT), glass transition temperature (T g), drying time and rubbing resistance to solvents were evaluated. The results showed that, when added to water-borne acrylic resins, an AFAD acts as a non-volatile plasticizer capable of autoxidative crosslinking with itself. 相似文献
76.
Pleurotus ostreatus spent mushroom substrate for the degradation of polycyclic aromatic hydrocarbons: the case study of a pilot dynamic biopile for the decontamination of a historically contaminated soil
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77.
Rafaela da Rosa Cardoso Edson Pinheiro de Lima Sergio E. Gouvea da Costa 《Journal of Manufacturing Systems》2012
AMT selection and adoption processes have been extensively studied. Topics that include financial and human factors, productivity, and coordination of the AMT implementation establish a substantial content of the present research agenda. The purpose of this paper is to study the organizational factors that influence the AMT implementation, considering a manufacturing strategy context and an analysis based on an organizational design framework. The research strategy is based on ‘empirical iterations’ using survey secondary data, experts’ interviews information and multiple case studies. The results show that there is a set of recommendations, which strongly influence the AMT implementation. Companies require a structured and integrative approach for the AMT implementation in order to take advantage of all their individual and systemic benefits. The set of proposed AMT recommendations for integrating these technologies to the organizational design are framed by structural, process and contextual aspects. 相似文献
78.
Leonardo Crauss Daronco Valter Roesler José Valdeni de Lima Ricardo Balbinot 《Multimedia Tools and Applications》2012,61(3):571-597
This paper presents a study of quality on scalable video sequences coded using the scalable extension of the H.264 standard (SVC). A group of experiments was performed to measure, primarily, the effects that transmission instability has in the quality of the videos and the relationship among three scalability methods (spatial, temporal and quality) in terms of quality. A set of experiments was performed to measure the subjective quality using the ACR-HRR methodology and recommendations from ITU-R Rec. BT.500 and ITU-T Rec. P.910. The results show that the amount of instability is not as important as just the presence of instability, that video quality can be deteriorated due to instability and that temporal scalability usually produces videos with worse quality than spatial and quality scalabilities. 相似文献
79.
F. Kahleyss R. Lima de Miranda T. Surmann C. Zamponi C. Machai D. Biermann E. Quandt 《Journal of Materials Engineering and Performance》2011,20(4-5):500-505
Nowadays, many manufacturing processes require the machining of complex forms with a high aspect ratio or cavities. Tools with a long overhang length are a common method to meet these requirements. Typical examples for this are boring bars for bore-turning and the milling with very long cutters. These tools tend to vibrate strongly due to their slender shape. The stress-induced transformation of austenite to martensite and the distinctive hysteresis loop allow the NiTi shape memory alloys (SMA) to absorb vibration energy. This article describes the innovative approach to dampen process vibrations by coating the tool shafts of cutting tools with long overhang with NiTi thin films. It explores how these thin films can be applied on polished tungsten carbide shafts and how their modal parameters are modified by these coatings. In a further step, this knowledge is used to calculate stability charts of corresponding machining processes. The study reported in this article identified the stabilizing effects of coatings with a thickness of 2-4 ??m on milling processes. The minimum stability limit was increased by up to 200%. 相似文献
80.
Tests of Random Walk: A Comparison of Bootstrap Approaches 总被引:1,自引:1,他引:0
This paper compares different versions of the multiple variance ratio test based on bootstrap techniques for the construction
of empirical distributions. It also analyzes the crucial issue of selecting optimal block sizes when block bootstrap procedures
are used. The comparison of the different approaches using Monte Carlo simulations leads to the conclusion that methodologies
using block bootstrap methods present better performance for the construction of empirical distributions of the variance ratio
test. Moreover, the results are highly sensitive to methods employed to test the null hypothesis of random walk. 相似文献