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31.
Ascensi G. Bruna J. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2009,55(5):2250-2259
We prove that the unique Gabor window leading to an analytic model space is the Gaussian one, and we give an analogous result for the wavelet transform. For the general case we give a new approach to study irregular Gabor and wavelet frames. We improve some known results for Gabor windows in the Feichtinger algebra, and for a special class of wavelets. 相似文献
32.
Bruna A. Kamimura Marciane Magnani Winnie A. Luciano Fernanda B. Campagnollo Tatiana C. Pimentel Vernica O. Alvarenga Beatriz O. Pelegrino Adriano G. Cruz Anderson S. Sant'Ana 《Comprehensive Reviews in Food Science and Food Safety》2019,18(5):1636-1657
A large variety of cheeses exist in Brazil, reflecting historical and cultural aspects. Brazilian artisanal cheeses present differences in the processing, ripening time (when applied), type of milk used, texture, size, shape, color, moisture content, flavor, the use or not of starter cultures, among others. This review describes the main artisanal cheeses produced in Brazil, focusing on general and particular characteristics associated with their making process and geographical identity. Overall, the high variability of the physicochemical data and deficiency of information on sensorial properties of Brazilian artisanal cheeses were noticed. On the other hand, culture‐dependent methods were mostly used to expand the knowledge into the microbiology of these cheeses, whereas their microbial diversity has been recently discovered through the use of 16S rRNA gene sequencing‐based methods. The certification of a geographical indication for Brazilian artisanal cheeses may encompass an essential milestone for adding value to these products. Regardless of their significance in the diet, culture, and economy of producing regions, taken together, the reviewed literature discloses the need of insightful studies to generate scientific data to support the expansion of the market, while ensuring the protection of historic aspects related to the production of Brazilian artisanal cheeses. 相似文献
33.
Ingrid Lessa Leal Yasmin Carolino da Silva Rosa Josenai da Silva Penha Paulo Romano Cruz Correia Pollyana da Silva Melo Danilo Hansen Guimarães Josiane Dantas Viana Barbosa Janice Izabel Druzian Bruna Aparecida Souza Machado 《应用聚合物科学杂志》2019,136(43):48150
In this study, formulations of cassava starch and poly(butylene adipate-co-terephthalate) flexible films were developed, with glycerol, coconut nanocellulose, annatto, and citric acid in different concentrations, as well as the effectiveness of the selected materials in fresh-cut mangoes storage was evaluated. The tensile strength of the different formulations varied from 1.90 (E4) to 6.65 MPa (E3c), and the strain varied from 206.31 (E1c) to 278.41% (E8); this variation was dependent on the percentage of the polymer matrix incorporated. The aw values of the formulations ranged from 0.396 (E2) to 0.569 (E3c). The Formulations E4 and E7 (with additives) presented good properties and were selected to condition mangoes. The micrographs of these films showed regions of micropores that can facilitate the diffusion of water from the packaged product to the surface, allowing decreases in moisture and aw, which is associated with higher color maintenance during fruit storage. E7 presented better barrier properties than E4 (lower values of WVP and water solubility) which may have influenced in a positive way to maintain the stability of the package in the studied period. E7 can be considered as a viable alternative for minimally processed mango storage. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48150. 相似文献
34.
Alessandro Pagano Irene Pluchinotta Raffaele Giordano Anna Bruna Petrangeli Umberto Fratino Michele Vurro 《Water Resources Management》2018,32(6):2131-2145
The availability and the quality of drinking water are key requirements for the well-being and the safety of a community, both in ordinary conditions and in case of disasters. Providing safe drinking water in emergency contributes to limit the intensity and the duration of crises, and is thus one of the main concerns for decision-makers, who operate under significant uncertainty. The present work proposes a Decision Support System for the emergency management of drinking water supply systems, integrating: i) a vulnerability assessment model based on Bayesian Belief Networks with the related uncertainty assessment model; ii) a model for impact, and related uncertainty assessment, based on Bayesian Belief Networks. The results of these models are jointly analyzed, providing decision-makers with a ranking of the priority of intervention. A GIS interface (G-Net) is developed to manage both input spatial information and results. The methodology is implemented in L’Aquila case study, discussing the potentialities associated to the use of the tool dealing with information and data uncertainty. 相似文献
35.
Bender Caroline R. Vicente Filipa A. Kuhn Bruna L. Frizzo Clarissa P. Villetti Marcos A. Carvalho Pedro J. 《Journal of Materials Science》2021,56(21):12171-12182
Journal of Materials Science - A cloud point evaluation was performed for the nonionic surfactant Tergitol 15-S-7 in aqueous solutions of McIlvaine buffer (pH 7.0). Cloud point temperatures of the... 相似文献
36.
Improvement of the short‐ and long‐term mechanical properties of injection‐molded poly(etheretherketone) and hydroxyapatite nanocomposites 下载免费PDF全文
Nanocomposites of polyetheretherketone (PEEK) and hydroxyapatite (HA) nanoparticles treated with a silane coupling agent were successfully prepared by twin screw extrusion and injection molding. Some of the samples were annealed after the injection molding. The silane treatment promoted an improvement of the short‐ and long‐term mechanical properties of the nanocomposites. A higher stress and a six times higher deformation at break and a higher impact strength were observed in the silane‐treated nanocomposites when compared to the nontreated ones. The number of cycles to fail of the treated nanocomposites was almost 200% higher than the number of cycles to fail of the nontreated samples. The treatment also decreased the glass transition temperature and amount of crystallinity of the samples. This improvement in mechanical properties obtained from the silane treatment was attributed to the strengthening of the PEEK/HA interfacial bond, to the plasticization of the PEEK matrix by silane oligomers produced during the processing and to a better dispersion of the HA nanoparticles within the PEEK matrix. Samples annealing, however, diminished all these properties due to the increase in crystallinity. Studies of the short‐ and long‐term mechanical properties of these nanocomposites under physiological conditions and of the proliferation of stem cells are under way. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44476. 相似文献
37.
Artificial intelligence approach for high level production of amylase using Rhizopus microsporus var. oligosporus and different agro‐industrial wastes 下载免费PDF全文
38.
Fábio G. Melchiades Bruna T. Rego Silvia M. Higa Helton J. Alves Anselmo O. Boschi 《Journal of the European Ceramic Society》2010,30(12):2443-2449
Transparency is an extremely important optical property of several glazes used in the ceramic tile sector. The present work aimed to identify the causes of loss of transparency presented by some ceramic glazes composed of frits with chemical compositions typical of optically transparent glasses. After identifying the causes of low transparency presented by several ceramic glazes based on microstructural analyses, X-ray diffraction and scanning electron microscopy, attempts were made to increase the transparency of these glazes by altering their chemical compositions. The results suggest that the addition of alumina – through distinct mineral sources – may be an interesting alternative to prevent the crystallization of calcium silicates, which reduce the transparency of glazes used in the ceramic tile sector. 相似文献
39.
40.
Helena Ribeiro Joana Marto Sara Raposo Maria Agapito Vera Isaac Bruna G. Chiari Pedro F. Lisboa Alexandre Paiva Susana Barreiros Pedro Simões 《European Journal of Lipid Science and Technology》2013,115(3):330-336
Spent coffee grounds (SCG), which are the residue obtained from the treatment of coffee with hot water or steam, can be used for industrial applications, due to the high content in lipids. The cosmetic products might be a suitable application for these types of residues because the barrier properties of the stratum corneum (SC) are largely dependent on the intactness of the lipid lamellae that surrounds the corneocytes. The purpose of this work was to assess the feasibility of using the lipid fraction of SCG extracted with supercritical carbon dioxide in the development of new cosmetic formulations with improved skin lipids (sebum) and hydration. The use of spent coffee lipid extract in cosmetic industry seems to be a suitable approach to recycle the wastes from coffee industry. Emulsion containing 10% of the lipid fraction of SCG (SpentCofOil cream) presented promising characteristics in the improvement of sebum skin levels with a good acceptance by consumers when compared to an emulsion containing 10% w/w of green coffee oil (GreenCofOil cream) and a placebo without coffee oil (NoCofOil cream). Practical applications: In this work, the authors develop and characterize a cream containing 10% of the lipid fraction of SCG extracted with supercritical carbon dioxide with improved skin lipids (sebum) and hydration. 相似文献