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921.
Margarita Angelidou 《城市工程杂志》2017,24(4):3-28
This paper identifies the characteristics of smart cities as they emerge from the recent literature. It then examines whether and in what way these characteristics are present in the smart city plans of 15 cities: Amsterdam, Barcelona, London, PlanIT Valley, Stockholm, Cyberjaya, Singapore, King Abdullah Economic City, Masdar, Skolkovo, Songdo, Chicago, New York, Rio de Janeiro, and Konza. The results are presented with respect to each smart city characteristic. As expected, most strategies emphasize the role of information and communication technologies in improving the functionality of urban systems and advancing knowledge transfer and innovation networks. However, this research yields other interesting findings that may not yet have been documented across multiple case studies; for example, most smart city strategies fail to incorporate bottom-up approaches, are poorly adapted to accommodate the local needs of their area, and consider issues of privacy and security inadequately. 相似文献
922.
Margarita N. Shurupova Andrei A. Zverev 《The International journal of environmental studies》2017,74(5):724-731
AbstractThe criteria for assessing conservation categories of rare species are not identical in drafting the red lists of Russia and the IUCN. By the example of genus Saussurea (Compositae), we have shown that the conservation measures for some endangered species do not match their state. We conducted indicator analyses on two factors of more than 9000 relevés with Saussurea species with large ranges and determined their rarity types according to D. Rabinowitz. Only 2 Siberian Saussurea species are not characterised by any type of rarity. The other 54 taxa all feature a small range, low abundance or high habitat specificity. 相似文献
923.
González-Fonteboa Belén Martínez-Abella Fernando Carro López Diego Seara-Paz Sindy 《Construction and Building Materials》2011,25(5):2335-2342
In this work the stress–strain curve of the recycled concretes was determined by replacing different percentages of the natural coarse aggregate with recycled coarse aggregate (20%, 50% and 100%). The results made it possible to establish the differences between the stress–strain relationship of a conventional concrete and this relationship for a recycled concrete depending on the percentage of replacement. In this way, it was found that the longitudinal strain of the recycled concretes increases with the percentage of recycled coarse aggregate used.Finally, using the experimental results, an analytical expression of the stress–strain curve accounting for the percentage of replacement was developed. The verification of the proposed model equation was done by comparing it to the experimental data. The results show that the proposed model equation satisfactorily describes the effect of the recycled aggregate on the stress–strain curve. 相似文献
924.
F. López-Gayarre C. López-Colina M.A. Serrano-López E. García Taengua A. López Martínez 《Construction and Building Materials》2011,25(10):3802-3809
The study presented in this paper has been carried out using a highly fractional factorial experimental design. This design allows the analysis of a greater number of factors and levels with a reduced number of mixes. In the state of art of recycled concrete the studies have been carried out varying the level of one factor while the rest remained fixed. However an excessive number of factors or levels are not considered. This highly simplified test program was designed in order to make the number of tests viable whilst guaranteeing the reliability of the conclusions. The concrete has been produced by substituting the natural coarse aggregates for recycled aggregates from construction and demolition waste, which is mainly composed of concrete. In this research some factors that have not been analyzed in previous studies, such as the granular structure of the concrete or the replacement criteria, have been studied. The properties of recycled concrete analyzed were: density, absorption, compressive strength, elastic modulus and penetration of water under pressure. The concrete was made with dry recycled aggregate. The percentage of replacement of the recycled aggregate did not affect the compressive strength since the water/cement rate remained constant. However the elastic modulus is affected by the percentage of replacement when it exceeds 50%. 相似文献
925.
Fabio Kalesnik Pablo Aceñolaza Martín Hurtado Jorge Martínez 《Water and Environment Journal》2011,25(1):88-98
The relationship between environmental heterogeneity and the vegetation of the levee neo‐ecosystems in the Delta of the Paraná River was studied. These habitat types were considered plant communities of recent origin related to local productive activities. Vegetation coverage was evaluated in 97 plots of three different environmental units (A, B and C), using classification analysis, indirect and direct ordinations. The differential vegetation in different environmental units could be related to a greater fluvial influence of the Paraná River on unit A and a greater tidal influence of the de la Plata River on units B and C. The Lower Delta hydrological regimes only affect a few of edaphic variables particularly pH, organic matter percentage and clay content. To understand the spatial pattern of neo‐ecosystems vegetation, it is also necessary to consider the invasion of alien species that has been taking place for over 50 years. 相似文献
926.
Resveratrol and Related Stilbenoids,Nutraceutical/Dietary Complements with Health‐Promoting Actions: Industrial Production,Safety, and the Search for Mode of Action 下载免费PDF全文
927.
928.
Märt Kolnes Arvo Mere Jakob Kübarsepp Mart Viljus Birgit Maaten Marek Tarraste 《粉末冶金学》2018,61(3):197-209
From the outlook of healthcare, economic importance and supply risk, utilisation of raw materials like tungsten, cobalt and nickel should be reduced or replaced with other metals. Nontoxic titanium carbide and iron are the top-of-the-line solution for displacing these materials. Our focus was on conventionally fabricated titanium carbide-based cermets with a chromium ferritic steel binder. To study microstructural evolution, specimens were sintered at different temperatures (600–1500°C). We used a scanning electron microscopy, X-ray diffraction and differential scanning calorimetry to analyse the microstructure and phase formation of the cermets. Our results showed that during the solid and liquid phase sintering of the TiC–FeCr cermet, chromium ferrous complex carbides M7C3 are formed and as a result, chromium content in the binder phase is decreased. Alloying TiC–FeCr cermets with strong carbide formers improves the structural homogeneity of the cermets. Also, mechanical characteristics (hardness, fracture toughness) were evaluated. 相似文献
929.
Tâmmila Venzke Klug Elena Collado Ascensión Martínez-Sánchez Perla A. Gómez Encarna Aguayo Mariano Otón Francisco Artés Francisco Artés-Hernandez 《Food and Bioprocess Technology》2018,11(3):561-571
Nowadays, consumers demand healthy, safe, and ready-to-eat horticultural products because of their lifestyle. In this regard, new legume-based food product development with eco-innovative technologies seems to be an interesting market. The effect on quality of an innovative pesto sauce, made of fresh faba bean seeds, of an alternative continuous microwave treatment pasteurization (MW, 11 kW; 30 s) regarding a conventional pasteurization (85 °C; 5 min) throughout 20 days at 5 °C was studied. Non-heated blended samples were used as control. The microbial quality was satisfactory in all treatments. MW treatment improved the sensorial quality of pesto sauce and decreased condensed tannins. Additionally, MW-treated samples showed the best texture, consistency, and color, preserving its chlorophyll and carotenoid content. On the other hand, thermal treatments showed a decrease in total phenolic compounds (TPC) and antioxidant capacity (TEAC) after heating, regarding control samples; however, TPC and TEAC remained quite constant throughout the storage. 相似文献
930.
Marianela Hazel Álvarez-Hernández Francisco Artés-Hernández Felipe Ávalos-Belmontes Marco Antonio Castillo-Campohermoso Juan Carlos Contreras-Esquivel Janeth Margarita Ventura-Sobrevilla Ginés Benito Martínez-Hernández 《Food and Bioprocess Technology》2018,11(3):511-525
Fruit and vegetables are much appreciated by consumers due to their nutritional values and health-promoting compounds. However, different factors affect the postharvest life of such products, in where ethylene is a major one, even at low concentrations, besides temperature and relative humidity. Therefore, high attention has been focused on the development of effective tools to remove ethylene from the atmosphere surrounding these products during storage or in transit. Potassium permanganate scrubbers are one of the most used technologies to remove ethylene from horticultural products. To facilitate and improve the oxidation process, potassium permanganate has been supported onto inert solid materials of a small particle size. In this review, we aim to provide an outline of the most common materials used as potassium permanganate supports on postharvest treatment and their respective effects on quality aspects of various fresh produce during postharvest life. Vermiculite, activated alumina, zeolite, silica gel, activated carbon and clays are the most popular materials that have been used as a support of potassium permanganate-based ethylene scrubbers. The literature suggests that potassium permanganate supported onto silica gel or zeolite seems to be a promising tool to maintain fruit and vegetables quality attributes for long-term storage. Although vermiculite and activated alumina are the most commonly used materials to reach this goal, not promising results have been reported. 相似文献