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11.
Karina Fullenkamp Macarena Montané Gustavo Cáceres Gerardo Araya-Letelier 《国际可持续能源杂志》2019,38(6):561-582
In order to improve the thermal efficiency of building thermal energy storage (TES) systems, the feasibility of using encapsulated phase change materials (EPCMs) as heat storage media is analysed in this work. Specifically, the finite element method is used to perform thermal behaviour analyses of several EPCMs. These analyses include technical and economic assessments in order to identify the best combination of PCM and shell material, using as main parameters: thermal energy storage, heat transfer rate, materials cost, among others. The results show that EPCMs composed by Na2SO4·6H2O as PCM and covered by stainless steel highlight as TES materials. 相似文献
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Fabiana Helen Santos Luana Elisa Siqueira Giselle Pereira Cardoso Gustavo Molina Franciele Maria Pelissari 《应用聚合物科学杂志》2021,138(35):50887
The increasing use of non-biodegradable materials and the difficulty in recycling most of the available packaging have been pushing the development of biodegradable packaging. In this study, the potential uses of agroindustrial wastes to produce biodegradable films with antioxidant capacity were investigated. Starch films were produced by casting method using bran from jaboticaba peel, mango peel, and broccoli stalk. The influence of the concentration or type of bran in the properties of the films was evaluated through a central composite design. The results were analyzed by response surface and desirability function. Except for elongation and water solubility, the fitted equations were predictive in all studied properties. The films prepared from a higher concentration of mango peel exhibited better antioxidant capacity, while the broccoli stalk had no significant effect on antioxidant properties. The optimal formulation of the film (2.8% of jaboticaba peel and 20.0% of mango peel) and their predicted response variables (0.8 MPa for tensile strength, 40.0 MPa for Young's modulus, 4.5 mg/ml for IC50, and 41.6% for inhibition percentage) were defined according to the results. The optimization was satisfactory and the film presented high antioxidant capacity and moderate mechanical properties, proving to be an alternative to replace plastic packaging. 相似文献
14.
de Aquino Silva Rogerio da Silva Luana Dutra Moisés Lima de Araujo Gustavo Medeiros 《Mobile Networks and Applications》2021,26(1):319-325
Mobile Networks and Applications - The text mining process typically involves the application of natural language processing (NLP) techniques, in order to obtain important information and extract... 相似文献
15.
Alejandro Torres-Haro Melchor Arellano-Plaza Juan C. Mateos-Díaz Hugo Espinosa-Andrews Gustavo A. Castillo-Herrera 《International Journal of Food Science & Technology》2022,57(2):1040-1049
Xanthophyllomyces dendrorhous is one of the most attractive natural sources of astaxanthin. The yeast produces the compound intracellularly, therefore, it is necessary to evaluate cell rupture methods using clean and efficient technologies for its extraction and it subsequent use in industries. At present work, two non-conventional high-pressure extraction methods were evaluated for astaxanthin recovery: Supercritical fluid extraction and microfluidisation. Results: Effect of pressure (15, 30, and 45 Megapascals; MPa), Temperature (313 and 343 °K) and usage of co-solvent were studied in supercritical extraction process, meanwhile the effect of microfluidisation process (five stages and 160 MPa) for cell rupture and its combination with conventional technics (lithic enzymes, glass beads and ultrasonication) for the recovery of astaxanthin were evaluated. Supercritical fluid extraction presented a higher astaxanthin recovery, 54% yield extraction, at 32.5 MPa and 313 °K, and using ethanol as co-solvent, compared to a 31% yield extraction by mean microfluidisation process at 160 MPa combined with 15 min of sonication (amplitude of 80%). 相似文献
16.
Lauane G. Moreno Paulo H. Evangelista-Silva Edivânia C. Santos Rodrigo P. Prates Artenizia C. Lima Mateus F. Mendes Vinícius O. Ottone Marcelo H. F. Ottoni Wagner F. Pereira Gustavo E. B. A. Melo Elizabethe A. Esteves 《European Journal of Lipid Science and Technology》2021,123(9):2000332
Inflammatory bowel diseases (IBD) affect the gastrointestinal tract, and the imbalance of intestinal immune homeostasis can trigger them. Pequi oil (PO), a monounsaturated (MUFA) and carotenoid-rich food with nutraceutical potential, could help reshape the intestinal immune response, ameliorating IBD outcomes. This study investigates the effects of a 28 days intake of PO on elements of the intestinal immune response of mice with DSS-induced ulcerative colitis (disease activity index, colonic damage, inflammatory cells and markers). PO reduces body weight, colonic crypt and goblet cell losses and ameliorates diarrhea. In the colon, it increases γδT cells and secretory-IgA and decreases CD8+T cells. In lymphoid organs, it reduces CD8+T cells. Moreover, it also reduces the IL-17 and CRP in plasma. PO oil promotes a less cytotoxic response that may protect mice from immunological injuries caused by an IBD in the intestinal mucosa, improving the disease prognosis. Practical applications: This study demonstrates that the intake of pequi oil contributes to the regulation of immune response and improves clinical and histological signs of DSS-induced ulcerative colitis in mice. Its effects in cytotoxic cell reduction and other inflammatory markers and stimulation of regulatory cells, and preservation of mucus-producing cells, provide news insights about the importance of the regular intake of this food to better prognosis of ulcerative colitis acute episodes. In addition, these findings encourage further studies with foods with a protective potential for the intestinal mucosa. 相似文献
17.
Gustavo F. Brito Pankaj Agrawal Edcleide M. Araújo Tomás J.A. Mélo 《Polymer Engineering and Science》2014,54(8):1922-1930
Blends of poly(lactic acid) (PLA) and ethylene/methyl acrylate/glycidyl methacrylate terpolymer (EMA‐GMA) with and without the addition of an organoclay were prepared by melt mixing in a twin screw extruder. Mechanical, morphological, structural, and rheological properties of the systems have been investigated as function of its compositions. The impact strength (IS) of PLA increased with the addition of EMA‐GMA. Furthermore, the addition of 2.5 wt% of organoclay to the PLA/EMA‐GMA blend promoted improvements in the mechanical properties, such as IS, tensile strength, and strain‐at‐break. Further addition of organoclay, 5 wt%, led to a formation of a double percolated network, where the clay particles form bridges across EMA‐GMA droplets and glue them together, however, without coalescence. In addition, morphological and wide‐angle X‐ray scattering analyses evidenced that the clay presents a partially exfoliated structure and that remains inside the EMA‐GMA droplets, probably as a consequence of the approach used to produce the systems. POLYM. ENG. SCI., 54:1922–1930, 2014. © 2013 Society of Plastics Engineers 相似文献
18.
Silvia Claros Gustavo A. Rico-Llanos José Becerra José A. Andrades 《International journal of molecular sciences》2014,15(7):11255-11274
Transforming growth factor-beta (TGF-β) is involved in processes related to the differentiation and maturation of osteoprogenitor cells into osteoblasts. Rat bone marrow (BM) cells were cultured in a collagen-gel containing 0.5% fetal bovine serum (FBS) for 10 days in the presence of rhTGF (recombinant human TGF)-β1-F2, a fusion protein engineered to include a high-affinity collagen-binding decapeptide derived from von Willebrand factor. Subsequently, cells were moderately expanded in medium with 10% FBS for 4 days and treated with a short pulse of rhBMP (recombinant human bone morphogenetic protein)-2 for 4 h. During the last 2 days, dexamethasone and β-glycerophosphate were added to potentiate osteoinduction. Concomitant with an up-regulation of cell proliferation, DNA synthesis levels were determined. Polymerase chain reaction was performed to reveal the possible stemness of these cells. Osteogenic differentiation was evaluated in terms of alkaline phosphatase activity and mineralized matrix formation as well as by mRNA expression of osteogenic marker genes. Moreover, cells were placed inside diffusion chambers and implanted subcutaneously into the backs of adult rats for 4 weeks. Histological study provided evidence of cartilage and bone-like tissue formation. This experimental procedure is capable of selecting cell populations from BM that, in the presence of rhTGF-β1-F2 and rhBMP-2, achieve skeletogenic potential in vitro and in vivo. 相似文献
19.
Unique Crystal Structure of a Novel Surfactant Protein from the Foam Nest of the Frog Leptodactylus vastus 下载免费PDF全文
Dr. Denise Cavalcante Hissa Dr. Gustavo Arruda Bezerra Dr. Ruth Birner‐Gruenberger Dr. Luciano Paulino Silva Dr. Isabel Usón Prof. Dr. Karl Gruber Prof. Dr. Vânia Maria Maciel Melo 《Chembiochem : a European journal of chemical biology》2014,15(3):393-398
Breeding by releasing eggs into stable biofoams (“foam nests”) is a peculiar reproduction mode within anurans, fish, and tunicates; not much is known regarding the biochemistry or molecular mechanisms involved. Lv‐ranaspumin (Lv‐RSN‐1) is the predominant protein from the foam nest of the frog Leptodactylus vastus. This protein shows natural surfactant activity, which is assumed to be crucial for stabilizing foam nests. We elucidated the amino acid sequence of Lv‐RSN‐1 by de novo sequencing with mass‐spectrometry and determined the high‐resolution X‐ray structure of the protein. It has a unique fold mainly composed of a bundle of 11 α‐helices and two small antiparallel β‐strands. Lv‐RSN‐1 has a surface rich in hydrophilic residues and a lipophilic cavity in the region of the antiparallel β‐sheet. It possesses intrinsic surface‐active properties, reducing the surface tension of water from 73 to 61 mN m?1 (15 μg mL?1). Lv‐RSN‐1 belongs to a new class of surfactants proteins for which little has been reported regarding structure or function. 相似文献
20.
Julia Contreras-García Miriam Marqués José Manuel Menéndez José Manuel Recio 《International journal of molecular sciences》2015,16(4):8151-8167
Understanding the electronic nature of materials’ compressibility has always been a major issue behind tabulation and rationalization of bulk moduli. This is especially because this understanding is one of the main approaches to the design and proposal of new materials with a desired (e.g., ultralow) compressibility. It is well recognized that the softest part of the solid will be the one responsible for its compression at the first place. In chemical terms, this means that the valence will suffer the main consequences of pressurization. It is desirable to understand this response to pressure in terms of the valence properties (charge, volume, etc.). One of the possible approaches is to consider models of electronic separability, such as the bond charge model (BCM), which provides insight into the cohesion of covalent crystals in analogy with the classical ionic model. However, this model relies on empirical parametrization of bond and lone pair properties. In this contribution, we have coupled electron localization function (ELF) ab initio data with the bond charge model developed by Parr in order to analyze solid state compressibility from first principles and moreover, to derive general trends and shed light upon superhard behavior. 相似文献