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51.
Laia Ferrer-Martí Anna Garwood José Chiroque Benito Ramirez Oliver Marcelo Marianna Garfí Enrique Velo 《Renewable & Sustainable Energy Reviews》2012,16(7):5379-5390
Electrification systems based on renewable energy have proven suitable for providing electricity autonomously to rural communities. Among the technical options available, wind systems are increasingly getting attention. In the northern mountains of Peru, at 3800 m.a.s.l., three community wind electrification projects have been implemented. The technical solutions used in each project are different: wind vs. hybrid photovoltaic-wind systems; individual equipment vs. microgrids. This study aims to describe, evaluate and compare these three small-scale community wind electrification projects. The evaluation of the three projects was carried out by comparing previous and present scenario; attention has been focused on project design and technical aspects, socio-economic impacts and sustainability and management model. These three examples shed light on both the advantages and disadvantages of different technological options as well as on appropriate community-level management models. 相似文献
52.
Nicolle Dal’Acqua Ana Claudia Rangel Faria Mário César Vebber Hernane da Silva Barud Marcelo Giovanela Giovanna Machado Janaina da Silva Crespo 《International Journal of Hydrogen Energy》2018,43(33):15794-15806
The issues related to renewable energy sources is a matter of great worldwide appeal due to the increasing energy demand, instability in oil prices and environmental problems. In this context, the purpose of this study was to prepare self-assembled films of polyallylamine hydrochloride and poly (acrylic acid) supported onto bacterial cellulose membranes by a layer-by-layer approach with titanium dioxide (TiO2) nanoparticles and different concentrations of gold for application in hydrogen gas (H2) production by photocatalysis. The influence of the gold concentration and the presence and size of the gold nanoparticles (Au NPs), as well as the surface and thickness of the films on H2 production was investigated. The results showed that the film, prepared with a lower concentration of gold, presented the smallest Au NPs and, therefore, greater contact with the TiO2 nanoparticle surfaces, producing more H2. By analyzing the variation in all the experimental parameters used in the preparation of the films, it can be concluded that the best H2 production achieved was 29.12 μmol h?1 cm2. 相似文献
53.
Everton Barbosa Nunes Nathália Escóssio Cavalcante Alexandre Sousa Barreto Antônio Ítalo Neves da Silva Marcelo Ferreira Motta 《Welding International》2017,31(3):173-183
Plasma powder surfacing is one of the latest processes for application of coatings, with control of dilution as its main feature. Surfacing with superduplex stainless steels is an interesting option for the construction and repair of equipment for applications in a highly corrosive environment, allowing the desired characteristics to be achieved: corrosion resistance and good mechanical properties. The aim of this work is to assess the ferrite content in the weld metal and the mechanical characteristics via microhardness profiles in surfacing of C-Mn steel pipes with deposition of UNS S32760 by plasma powder surfacing. Welding operations were carried out on pipes with deposition of SDSS, employing three welding heat input levels, varying the welding speed or the welding current. Then the geometry was analysed, the ferrite content in the weld metal was quantified and the microhardness profile was recorded. Variation in welding heat input caused changes in weld bead geometry, with variation in the welding current producing the most significant changes. Increase in heat input caused decrease in ferrite content of the weld metal. Regarding microhardness, only the condition with a higher level of welding current gave sufficiently high levels of microhardness in the weld metal. 相似文献
54.
Flávia Mesquita Cabrini Mathilde Champeau Marcelo Ganzarolli de Oliveira 《应用聚合物科学杂志》2020,137(36):49056
Changing the pore morphology of hydrogels can be an effective strategy to modulate their drug release profiles. Herein, Pluronic F127 was used to change the three-dimensional pore morphology of crosslinked poly(N-isopropylacrylamide-co-acrylic acid) (P[NIPAm-co-AAc]) hydrogels. F127 reduced the pore diameters from 20 ± 4 to 2.9 ± 0.4 μm and from 11 ± 1 to 1.4 ± 0.4 μm in hydrogels synthesized at 8 and 30°C, respectively. Small-angle X-ray scattering indicates that the segregation of the F127 during the polymerization process induces F127 phase transitions from unimers (at 8°C) or cubic-packed micelles (at 30°C) to a lamellar structure. P(NIPAm-co-AAc) hydrogels charged with S-nitrosoglutathione (GSNO), released nitric oxide (NO) spontaneously during hydration. The decrease in the pore diameter led to a twofold to threefold increase in the rate of water absorption and a fourfold to sixfold increase in the rate of NO release of the hydrogels. F127 can be used to change the pore morphology of P(NIPAm-co-AAc) hydrogels, with concomitant changes in their rate of hydration and NO release from GSNO, opening a new perspective for their use in topical NO delivery. 相似文献
55.
Marta Arenas‐Jal J. M. Su‐Negre Encarna García‐Montoya 《Comprehensive Reviews in Food Science and Food Safety》2020,19(2):574-594
World population growth and aging are posing unprecedented challenges in sustaining the health of 9.1 billion people that will be occupying the planet by 2050. Although noncommunicable diseases such as cardiovascular and neurodegenerative diseases, cancer, and diabetes are among the top 10 global causes of death, they can be prevented by risk factor reduction, early detection, and adequate treatment. Since a healthy diet along with dietary supplementation could play an important role to reduce morbidity and cut off its associated health care costs, research in the food and nutrition area is required to find solutions to global challenges affecting health. As a result of the healthy living trend, dietary supplements category is growing fast, leading to an urgent need for dietitians, physicians, and policy makers to broaden the scientific evidence on the efficacy and safety of a wide range of active ingredients. Coenzyme Q10 (CoQ10), as the third most consumed dietary supplement, and as a potential candidate for the treatment of various noncommunicable diseases that are among the global top 10 causes of death, has gained interest over years. Scientific evidence regarding mainly CoQ10 efficacy and safety, as well as formulation challenges, is addressed in this review. 相似文献
56.
Brettanomyces is a semi‐domesticated yeast that is a crucial component of lambic beers and is increasingly attracting the attention of the brewing industry. Brettanomyces display Saccharomyces‐like features, such as a positive Crabtree effect, ethanol synthesis and tolerance to harsh environments. Additionally, Brettanomyces exhibit β‐glucosidase and esterase activities, the production of phenolic compounds and tetrahydropyridines, together with the ability to ferment dextrins and breakdown cellobiose from wooden casks. Although the importance of Brettanomyces species is documented in the production of different beer styles, the molecular and biochemical features of these species required for brewing are poorly understood. Therefore, this work reviews the current knowledge of the molecular biology and biochemistry underlying the performance of Brettanomyces in the brewing industry. © 2019 The Institute of Brewing & Distilling 相似文献
57.
Engineering with Computers - This work presents a new efficient array-based algorithm for adaptive mesh refinement capable of interactively generating millions of triangles. The new refinement... 相似文献
58.
Cíntia Maia Braga Acácio Antonio Ferreira Zielinski Karolline Marques da Silva Frederico Koch Fernandes de Souza Giovana de Arruda Moura Pietrowski Marcelo Couto Daniel Granato Gilvan Wosiacki Alessandro Nogueira 《Food chemistry》2013
The aim of this study was to assess differences between apple juices and fermented apple beverages elaborated with fruits from different varieties and at different ripening stages in the aroma profile by using chemometrics. Ripening influenced the aroma composition of the apple juice and fermented apple. For all varieties, senescent fruits provided more aromatic fermented apple beverages. However, no significant difference was noticed in samples made of senescent or ripe fruits of the Lisgala variety. Regarding the juices, ripe Gala apple had the highest total aroma concentration. Ethanal was the major compound identified in all the samples, with values between 11.83 mg/L (unripe Lisgala juice) and 81.05 mg/L (ripe Gala juice). 3-Methyl-1-butanol was the major compound identified in the fermented juices. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied and classified the juices and fermented juices based on physicochemical and aroma profile, demonstrating their applicability as tools to monitor the quality of apple-based products. 相似文献
59.
60.
H Arenas Márquez F López Neblina H Barrera Torres MR Flores Márquez 《Canadian Metallurgical Quarterly》1994,59(1):49-51
The presence of an earlier latency of 12 msec of a somato-sensory evoked potential elicited by the stimulation of the median nerve at the wrist was discovered in 1963 by Liberson and Kim. They suggested its origin in the cervical spine or in the brain stem and possibly the cerebellum. Liberson, Voris and Uematsu recorded directly these potentials from the cervical spine and from the mesencephalon during surgery for pain in 1969 and published some of the findings in 1970. Cracco and Bickford confirmed in 1968 the findings of Liberson and Kim. 相似文献