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排序方式: 共有1545条查询结果,搜索用时 31 毫秒
51.
52.
Hayane Ferreira Leite Ladislau Thaísa Gabriela Silva de Farias Bruna Lúcia Mendonça Soares José Alberto da Costa Medeiros Natália Ferrão Castelo Branco Melo Thatiana Montenegro Stamford–Arnaud Thayza Christina Montenegro Stamford Tânia Lucia Montenegro Stamford 《International Journal of Food Science & Technology》2021,56(10):5395-5401
This research verified the ability of Lactobacillus rhamnosus encapsulated with inulin to tolerate the simulated digestive system and their viability in a soy blend. Probiotic encapsulated in alginate-chitosan matrix without inulin presented a better encapsulation efficiency (80.92%) than encapsulation with inulin (57.39%). On the 28th day, the count of probiotics decreased by 3.42 and 1.99 logarithmic cycles of free and encapsulated cells without inulin, respectively. In contrast, the microorganisms encapsulated with inulin showed an increase of 1.26 logs CFU g−1. During gastrointestinal simulation, cell counts decreased by 0.78, 1.55 and 1.95 CFU g−1 logs for encapsulated cells without inulin, free and encapsulated with inulin, respectively. Sensory panellists liked the fermented soy blend with encapsulated lactobacilli, and this result shows the possibility to create new probiotic foods of plant origin. Therefore, the alginate/chitosan matrix can be considered adequate for the encapsulation of L. rhamnosus. The inulin reduces the encapsulation efficiency and increases the cell loss in gastrointestinal simulation. Considering cellular losses, the best option for preparing a fermented soy blend is to use L. rhamnosus encapsulated without inulin. 相似文献
53.
54.
Vanessa Migliorini Urban Ana Lucia Machado Carlos Eduardo Vergani Eunice Teresinha Giampaolo Ana Cláudia Pavarina Quezia Bezerra Cass 《应用聚合物科学杂志》2012,123(2):732-739
The effect of a post‐polymerization treatment on the leaching of methacrylic acid (MA) and benzoic acid (BA) from the reline resins [Kooliner (K), New Truliner (N), Ufi Gel hard (U), and Tokuso Rebase Fast (T)] was evaluated. Specimens of each material were divided into two groups: Group C (control) – left untreated; Group WB (water‐bath) – immersion in water at 55 ± 1°C for 10 min. Specimens were placed in artificial saliva at 37 ± 1°C and, after 1‐, 3‐, 5‐, 24‐h and 3‐, 7‐, 14‐, and 30‐day intervals, aliquots were removed and analyzed using high performance liquid chromatography. Data were analyzed by using Wilcoxon, Mann–Whitney or Kruskal–Wallis tests (α = 0.05). At 1 h, the concentration of MA released from U control specimens was higher than those of the other ones, and decreased after 3 h. WB specimens released lower amounts of MA than control specimens only for material U, at the 1‐ and 3‐h periods. For all control specimens, concentrations of leached BA progressively decreased within 5 h and from 24 h to the end. WB specimens released significantly lower amounts of BA than did the control groups. The highest concentration of MA was leached from control specimens of Ufi Gel hard. Water‐bath post‐polymerization treatment caused a significant reduction in elution of BA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
55.
This paper aims at evaluating the sources of differences among countries' innovative performances in the renewable energy (RE) sector. Namely, we focus on the national innovative capacity, the knowledge developed abroad and the related knowledge spillovers. We claim that a country is more likely to develop RE innovation: (i) the larger the knowledge stocks of other countries in the same sector; (ii) especially when those other countries share established linkages with the focal country. Relying on a knowledge production function, we model country-level innovative performances in the RE sector for 18 OECD countries in the period 1990–2006. Our findings confirm that, once controlling for climate-energy policies, international knowledge spillovers contribute significantly to RE innovation, and their effect is comparable with domestic R&D and human capital. In addition, international spillovers are more likely if countries share stronger linkages. 相似文献
56.
Francesca Soglia Massimiliano Petracci Samer Mudalal Lucia Vannini Giorgia Gozzi Lucia Camprini Claudio Cavani 《International Journal of Food Science & Technology》2014,49(10):2184-2191
This study was aimed at evaluating the consequences of sodium chloride reduction by potassium chloride up to 50% on technological, sensorial and microbiological traits of marinated rabbit meat. In total, 226 rabbit loin meat samples were obtained and subjected to vacuum tumbling using solutions with different NaCl/KCl ratios. Replacing of sodium chloride up to 30% by potassium chloride did not change microbiological traits (total aerobic mesophilic and lactic acid bacteria maximum cell loads), sensorial acceptability (perceived saltiness and overall liking) and technological traits (pH, colour, texture, cooking loss and yield). Otherwise, reduction in sodium chloride to 50% significantly decreased perceived saltiness (4.15 vs. 4.73; P < 0.05) and reduced microbial shelf life by 1 day when compared to control, even if there was still no effect on technological traits. In conclusion, it is feasible imparting an added value for processed rabbit meat products by reduction in sodium content that could increase market interest. 相似文献
57.
Giuseppe Ragosta Mario Abbate Pellegrino Musto Gennaro Scarinzi 《Journal of Materials Science》2012,47(6):2637-2647
This article examines the effects of structural changes and thermal aging treatments on the relaxation processes and mechanical
properties of three polyimides differing for their molecular structure i.e. PMDA-ODA, 6FDA-ODA, and 6FDA-6FpDA. These polyimides
were obtained by thermal imidization of their polyamic acid precursors, which were synthesized from the respective dianhydrides
[pyromellitic anhydride (PMDA), hexahydrofluoroisopropylidene diphthalic anhydride (6FDA)], and diamines [4,4′-diaminodiphenyl
ether (ODA), 4,4′-(hexafluoroisopropylidene) dianiline (6FpDA)]. After the curing process, the polyimides were thermally aged
at a fixed temperature for various times Dynamic mechanical measurements performed in a multi-frequency mode, were used to
determine the glass-rubber and sub-glass transitions, as well as the activation energy of the β transition. It was found that
the T
g decreased in the order PMDA-ODA > 6FDA-6FpDA > 6FDA-ODA as a result of an increased chain rigidity and molecular packing
induced by charge transfer interactions during the thermal imidization process. The β sub-glass transition showed two relaxation
processes identified as β′ and β′′. The β′ process was attributed to the local motion of the diamine constituents while the
β′′ process was caused by the local motion of the dianhydride moiety. The cooperativity of these molecular motions was also
assessed via the Starkweather method. The thermal aging enhanced the state of aggregation of polyimide chains and thus the
T
g and the sub-glass transition properties. This effect was particularly marked for the PMDA-ODA polyimide. Also the mechanical
properties were significantly affected by chemical structure and aging treatments. For non-aged samples the more influenced
parameter was the elongation at break, which decreased in the order PMDA-ODA > 6FDA-ODA > 6FDA-6FpDA. The aging enhanced the
elastic modulus and the tensile strength and reduced the elongation at break. 相似文献
58.
How do the new building façade components work under real climatic conditions? The question is especially related to the dynamic behaviour of new and complex components such as the ventilated walls, the Phase Change Material, or others that use nano-technologies and aerogels. One of the objectives of the undergoing research activity, named Abitare Mediterraneo, is the evaluation of their thermal behaviour through the use of an outdoor test cell, in order to reproduce under the real external conditions the performance of these components, and consequently define the main thermal parameters such as the attenuation factor and the thermal inertia, characterising the component; moreover, the results will be used to write new algorithms for dynamic simulation tools allowing an appropriate evaluation of the complex behaviour of the whole building at a real scale condition. The new test cell is realised in Florence, Italy. The design starts from the study of the experience of the existing PASSYS test cells, overtaking the main weakness of the building structure and of the heat-flux sensors. 相似文献
59.
Hossam M. Zawbaa Serena Schiano Lucia Perez-Gandarillas Crina Grosan A. Michrafy Chuan-Yu Wu 《Advanced Powder Technology》2018,29(12):2966-2977
In pharmaceutical development, it is very useful to exploit the knowledge of the causal relationship between product quality and critical material attributes (CMA) in developing new formulations and products, and optimizing manufacturing processes. With the big data captured in the pharmaceutical industry, computational intelligence (CI) models could potentially be used to identify critical quality attributes (CQA), CMA and critical process parameters (CPP). The objective of this study was to develop computational intelligence models for pharmaceutical tabletting processes, for which bio-inspired feature selection algorithms were developed and implemented for optimisation while artificial neural network (ANN) was employed to predict the tablet characteristics such as porosity and tensile strength. Various pharmaceutical excipients (MCC PH 101, MCC PH 102, MCC DG, Mannitol Pearlitol 200SD, Lactose, and binary mixtures) were considered. Granules were also produced with dry granulation using roll compaction. The feed powders and granules were then compressed at various compression pressures to produce tablets with different porosities, and the corresponding tensile strengths were measured. For the CI modelling, the efficiency of seven bio-inspired optimization algorithms were explored: grey wolf optimization (GWO), bat optimization (BAT), cuckoo search (CS), flower pollination algorithm (FPA), genetic algorithm (GA), particle swarm optimization (PSO), and social spider optimization (SSO). Two-thirds of the experimental dataset was randomly chosen as the training set, and the remaining was used to validate the model prediction. The model efficiency was evaluated in terms of the average reduction (representing the fraction of selected input variables) and the mean square error (MSE). It was found that the CI models can well predict the tablet characteristics (i.e. porosity and tensile strength). It was also shown that the GWO algorithm was the most accurate in predicting porosity. While the most accurate prediction for the tensile strength was achieved using the SSO algorithm. In terms of the average reduction, the GA algorithm resulted in the highest reduction of inputs (i.e. 60%) for predicting both the porosity and the tensile strength. 相似文献
60.
Modular and Versatile Spatial Functionalization of Tissue Engineering Scaffolds through Fiber‐Initiated Controlled Radical Polymerization
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Rachael H. Harrison Joseph A. M. Steele Robert Chapman Adam J. Gormley Lesley W. Chow Muzamir M. Mahat Lucia Podhorska Robert G. Palgrave David J. Payne Shehan P. Hettiaratchy Iain E. Dunlop Molly M. Stevens 《Advanced functional materials》2015,25(36):5748-5757
Native tissues are typically heterogeneous and hierarchically organized, and generating scaffolds that can mimic these properties is critical for tissue engineering applications. By uniquely combining controlled radical polymerization (CRP), end‐functionalization of polymers, and advanced electrospinning techniques, a modular and versatile approach is introduced to generate scaffolds with spatially organized functionality. Poly‐ε‐caprolactone is end functionalized with either a polymerization‐initiating group or a cell‐binding peptide motif cyclic Arg‐Gly‐Asp‐Ser (cRGDS), and are each sequentially electrospun to produce zonally discrete bilayers within a continuous fiber scaffold. The polymerization‐initiating group is then used to graft an antifouling polymer bottlebrush based on poly(ethylene glycol) from the fiber surface using CRP exclusively within one bilayer of the scaffold. The ability to include additional multifunctionality during CRP is showcased by integrating a biotinylated monomer unit into the polymerization step allowing postmodification of the scaffold with streptavidin‐coupled moieties. These combined processing techniques result in an effective bilayered and dual‐functionality scaffold with a cell‐adhesive surface and an opposing antifouling non‐cell‐adhesive surface in zonally specific regions across the thickness of the scaffold, demonstrated through fluorescent labelling and cell adhesion studies. This modular and versatile approach combines strategies to produce scaffolds with tailorable properties for many applications in tissue engineering and regenerative medicine. 相似文献