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101.
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
102.
103.
Anna Delcampo‐Carda Ana Torres‐Barchino Juan Serra‐Lluch 《Color research and application》2019,44(3):381-395
The impact of the physical environment on individuals has arisen as a growing body of research in population wellbeing. Yet, most of studies in this area do not focus on elderly even though they are particularly susceptible to the characteristics of their interior spaces. It is a well‐known fact that to be old is to acquire a tolerance of disabilities based on the gradual degeneration. A common problem is a dysfunction in visual sensitivity and accordingly, the alteration of their environmental color perception. That is why these impairments need to be understood in order to minimize the elderly spatial difficulties. To know at what point there is a loss in the ability to perceive color is necessary to understand how should we take these facts into consideration. A state‐of‐the‐art literature review of current studies from the last 20 years is carried out. The aim is to analyze existing practices on Evidence‐Based Research through a multidisciplinary approach in order to create knowledge about chromatic built environments for the elderly. Data are identified and considered together with empirical experience about color, perception, built environment and elderly. Thus, the way in which elderly perceive the space is explored. The adjustments in the formulation of these impairments throughout any design strategy to adapt the environment to their physiological changes are determined. This article aims to determine a design interpretation of the various findings, demonstrating that color, as a parameter of the visual performance, influences visual comfort and helps performance in architecture for old people. 相似文献
104.
Ultra-high performance concrete and fiber reinforced concrete: achieving strength and ductility without heat curing 总被引:5,自引:2,他引:3
Kay Wille Antoine E. Naaman Sherif El-Tawil Gustavo J. Parra-Montesinos 《Materials and Structures》2012,45(3):309-324
Ultra-high performance concrete (UHPC) and ultra-high performance fiber reinforced concrete (UHP-FRC) were introduced in the
mid 1990s. Special treatment, such as heat curing, pressure and/or extensive vibration, is often required in order to achieve
compressive strengths in excess of 150 MPa (22 ksi). This study focuses on the development of UHP-FRCs without any special
treatment and utilizing materials that are commercially available on the US market. Enhanced performance was accomplished
by optimizing the packing density of the cementitious matrix, using very high strength steel fibers, tailoring the geometry
of the fibers and optimizing the matrix-fiber interface properties. It is shown that addition of 1.5% deformed fibers by volume
results in a direct tensile strength of 13 MPa, which is 60% higher than comparable UHP-FRC with smooth steel fibers, and
a tensile strain at peak stress of 0.6%, which is about three times that for UHP-FRC with smooth fibers. Compressive strength
up to 292 MPa (42 ksi), tensile strength up to 37 MPa (5.4 ksi) and strain at peak stress up to 1.1% were also attained 28 days
after casting by using up to 8% volume fraction of high strength steel fibers and infiltrating them with the UHPC matrix. 相似文献
105.
Rocio Velázquez Alejandro Hernández Alberto Martín Emilio Aranda Gustavo Gallardo Teresa Bartolomé Maria G. Córdoba 《International Journal of Food Science & Technology》2014,49(3):830-839
Several quality parameters of smoked, oven‐dried and sun‐dried paprikas were studied. Smoked paprikas showed the highest American Spice Trade Association (ASTA) units and pigment concentrations, whereas oven‐dried paprikas showed the best browning index and red/yellow pigment ratio, and sun‐dried paprikas had the highest redness for reflected colour. The colour stability results showed drastic overall colour change (ΔE) and decreased redness and ASTA units of the sun‐dried and oven‐dried paprikas after two and 5 days of UV exposure. Degradation of the smoked paprika colour parameters was progressive, and they showed less degradation even after 30 days. The evaluation of the antioxidant activity showed higher DPPH radical‐scavenging capacity in the smoked samples. The profiles of volatile phenolic compounds of the smoked samples are responsible for the differences in the antioxidant capacity. The great differences in colour stability and antioxidant activity make smoked paprika the best choice for use in the food industry. 相似文献
106.
In vitro digestibility of phenolic compounds from edible fruits: could it be explained by chemometrics?
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Francisco J. Olivas‐Aguirre Marcela Gaytán‐Martínez Sandra O. Mendoza‐Díaz Gustavo A. González‐Aguilar Joaquín Rodrigo‐García Nina del Rocío Martínez‐Ruiz Abraham Wall‐Medrano 《International Journal of Food Science & Technology》2017,52(9):2040-2048
The health benefits of phenolic compounds depend on the ingested amount, molecular diversity and gastrointestinal digestibility. The phenolic profile of eight fruits (blackberry, blueberry, strawberry, raspberry, mulberry, pomegranate, green and red globe grapes) was chemometrically associated with their in vitro digestibility (oral, gastric, intestinal). Extractable phenols, flavonoids and anthocyanins strongly correlated with each other (r ≥ 0.84), proanthocyanidins with anthocyanins (r = 0.62) and hydrolysable phenols with both extractable phenols (r = 0.45) and proanthocyanidins (r = ?0.54). Two principal components explained 93% of the variance [61% (free‐phenols), 32% (bounded‐phenols)], and four clusters were confirmed by hierarchical analysis, based in their phenolic richness (CLT 1‐4: low to high) and molecular diversity. In vitro digestibility of extractable phenols and flavonoids was blackberry (CLT‐4)> raspberry (CLT‐2)> red grape (CLT‐1) related to their phenolic richness (r ≥ 0.96; P < 0.001), but anthocyanins’ digestibility was pH‐dependent. Chemometrics is useful to predict the in vitro digestibility of phenolic compounds in the assayed fruits. 相似文献
107.
108.
Gustavo Sanchez César Marcon Luciano Agostini 《Journal of Real-Time Image Processing》2017,13(1):71-83
This article presents a real-time scalable hardware architecture for the bipartition modes of 3D high-efficiency video coding (3D-HEVC) standard, which includes the depth modeling modes 1 (DMM-1) and 4 (DMM-4). A simplification of the DMM-1 algorithm was done, removing the refinement step. This simplification causes a small BD-rate increase (0.09 %) with the advantage of better using our hardware resources, reducing the necessary memory required for storing all DMM-1 wedgelet patterns by 30 %. The scalable architecture can be configured to support all the different block sizes supported by the 3D-HEVC and also to reach different throughputs, according to the application requirements. Then, the proposed solution can be efficiently used for several encoding scenarios and many different applications. Synthesis results considering a test case show that the designed architecture is capable of processing HD 1080p videos in real time, but with other configurations, higher resolutions are also possible to be processed. 相似文献
109.
Y. Torres J.J. PavónJ.A. Rodríguez 《Journal of Materials Processing Technology》2012,212(5):1061-1069
Porous samples of commercially pure titanium (CP Ti) were fabricated by using sodium chloride (NaCl) as space-holder with percentages between 40 and 70 vol%. The dissolution of NaCl in distilled water, the structural integrity of samples and the reproducibility of the procedure were studied as a step prior to sintering. All these parameters were evaluated in terms of the compaction pressure, temperature and agitation of water, and dissolution time. The characterization of samples included density, porosity and dynamic Young's modulus. The results indicate that the most efficient lixiviation, according to the desired balance of properties, was by immersion in hot water, without agitation and for prolonged cycles of immersion time. 相似文献
110.