695 research outputs found

    Photocatalytic and thermochromic materials applied to road engineering

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    [Excerpt] Materials Science knowledge has been applied to Civil Engineering to provide new capabilities and benefits for the environment and society. Through the functionalization process with nano/microparticles, Civil Engineering materials can become smart. This study presents the main results of the research work with photocatalytic (nano-TiO2 ) and thermochromic (Leuco dye) materials on road pavements and road markings [1-5]

    Photocatalytic asphalt mixtures: Mechanical performance and impacts of traffic and weathering abrasion on photocatalytic efficiency

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    The photocatalytic asphalt mixture provides safer roads and mitigates the air quality problems, trapping and degrading organic compounds and also harmful gases. In this research, an asphalt mixture was functionalized with nano-TiO2 by bulk incorporation, using the contents 3 and 6%, and by spraying coating using an aqueous solution over its surface at different temperatures and rates. For bulk incorporation, the mechanical performance was assessed. The factors ? application procedure, influence of temperature, spraying rate, incorporation percentage and TiO2 immobilization (from traffic and rain removal) ? were evaluated based on Rhodamine B (RhB) degradation. For bulk incorporation, the best content nano-TiO2 was 3%. The temperature of the substrate has no influence on the photocatalytic results. The most effective spraying rates were 8 and 16?mL/cm2. Before simulating the traffic effect, the spraying coating technique was more effective than the bulk incorporation one. After this process, the opposite behavior was detected. The rain simulation did not cause removal of the nanoparticles. Additionally, the exposed aggregates affected the photocatalytic efficiency, being important their contribution combined to the effect of nano-TiO2. To have the maximum benefit of the techniques studied, the ideal solution would be the combination of both, with negligible impact on mechanical performance.This work was partially financed by FCT—Fundação para a Ciência e a Tecnologia—under the project PTDC/FIS/120412/2010: “Nanobased concepts for Innovative & Eco-sustainable constructive material’s surfaces’’ and project PEst-OE/ECI/UI4047/2014

    Ingestive Behaviour of Steers in Native Pastures in Southern Brazil

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    The Campos biome, particularly its native pastures, is the main resource for livestock production in southern Brazil (Boldrini, 1997). It has a huge floristic diversity in which more than 400 grass and 150 legume species are found. These pastures are very heterogeneous with horizontal as well as vertical structure. Hodgson (1985) stressed the importance of sward structure upon diet selection, emphasizing the difficulties animals could have to access all pasture layers in temperate pastures. This experiment investigates how variation in herbage allowance along the growing season influences the ingestive behaviour of steers

    Public Research Institutions and Their Connections with Patents of Companies in Technological and Regional Development

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    The interaction between companies and universities is a central theme in discussions on technology transfer. In Brazil, there is an urgent need to raise awareness of the importance of this cooperative relationship for local and regional development. In this sense, it is observed that the innovation process is strategic so that an institution is strengthened and can fulfill its social mission in economic and regional development. Piauí, according to the IBGE census, has a population estimate of 3,273,227 in 2019. Piaui\u27s per capita income is R$ 817.00 and ranks 24th in Brazil in this regard. With these data, the need arises to intervene scientifically in this reality. The objective of this study is to investigate the partnership relationships between companies and public research institutions in Piauí, in the development and transfer of technologies. Research Institutions are the main promoters of technological development in the state, however, for these technologies to reach productive arrangements, strategic alignment in the management of these technologies is necessary. Documentary research was used, with a quantitative approach. In the exploratory search, INPI\u27s databases (National Institute of Industrial Property) and of Espacenet ( European Patent Office ) was used. We sought to select the companies with relevant economic representativeness in the state scenario and investigated the patent information. In the analysis of the data obtained, the Competitiveness Ranking of the CLP States (Public Leadership) was used to compare Piauí with well positioned states. According to the results found, it is observed that the transfer of technology between research institutions and companies is not evident. However, we can see that there are partnership initiatives with small companies in conducting research that can project a change in this scenario. The low number of patents and public/private partnerships in driving innovation in the state of Piauí, may be related to the low index evidenced by the Competitiveness Ranking of States - CLP

    Somatic embryogenesis and plant regeneration in açaí palm (Euterpe oleracea).

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    Made available in DSpace on 2018-07-01T01:23:45Z (GMT). No. of bitstreams: 1 ScherwinskiPereira2012ArticleSomaticEmbryogenesisAndPlantRe.pdf: 490424 bytes, checksum: f61985361005a58dd8b71374dc38aac6 (MD5) Previous issue date: 2013-02-21bitstream/item/179316/1/Scherwinski-Pereira2012-Article-SomaticEmbryogenesisAndPlantRe.pd

    Avaliação de cultivares de alface americana em Santana da Vargem, MG.

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    Com o objetivo de avaliar cultivares de alface americana adaptadas ao verão, foi conduzido em Santana da Vargem, MG, um experimento contendo 17 cultivares. Utilizou-se o delineamento em blocos casualizados, com 3 repetições. Foram avaliadas a produtividade total e comercial, comprimento do caule, circunferência da cabeça e sanidade das folhas externas. Verificou-se que a maioria das cultivares apresentaram valores similares a cultivar Raider, tradicionalmente cultivada, em termos de produtividade total. Para produtividade comercial, as cultivares Lucy Brown, PSR 5338, PSR 4303, PSR 0110, Empire 2000 e Seeker, não diferiram significativamente da cultivar Raider (333,8 g/planta) com 266,6; 276,1; 293,8; 301,6; 304,4 e 333,8 g/planta, respectivamente. Em relação à circunferência de cabeça, com exceção da cultivar PSR 5338, as demais cultivares com melhores produtividades comerciais foram estatisticamente semelhantes, variando de 38,7 a 41,5 cm.Suplemento 2. Edição do Anais do 42 Congresso Brasileiro de Olericultura; 11 Congresso Latino Americano de Horticultura, Uberlandia, jul. 2002

    Avaliação de cultivares de alface americana em Santana da Vargem, MG, nas condições de inverno.

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    Com o objetivo de avaliar cultivares de alface americana adaptada ao cultivo de inverno, foi conduzido em Santana da Vargem, MG, um experimento contendo 42 cultivares. Utilizou-se o delineamento em blocos casualizados, com 3 repetições. As massas frescas totais variaram de 772 a 1268 g/planta nas diferentes cultivares. Os melhores desempenhos foram obtidos pelas cultivares P1823-0014 206-1 (1268 g/planta) e P1823-0014325-3 (1232 g/planta), que não diferiram estatisticamente entre si. Para a massa fresca comercial, a variação verificada foi de 378 a 729 g/planta. Entre os materiais superiores estatisticamente, obteve-se uma variação de 561 a 729 g/planta. Em relação a circunferência da cabeça comercial, entre os materiais avaliados houve uma variação de 35,6 a 49,2 cm. A cultivar que apresentou a maior circunferência, sendo estatisticamente superior às demais, foi a "P1823-0014325-3", com 49,2 cm. Quanto ao comprimento de caule, a variação entre os materiais foi de 1,9 a 4,9 cm.Suplemento. Edição de Resumos expandidos e palestras do 43. Congresso Brasileiro de Olericultura, Recife, jul. 2003

    Review and analysis of advances in functionalized, smart, and multifunctional asphalt mixtures

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    Road pavements are designed to withstand road traffic and weathering actions while ensuring comfortable and safe riding conditions as well as low costs and damage to the environment. When a road pavement has additional abilities or reacts to an external stimulus, it is considered to be smart and multifunctional. Examples of such abilities that have been investigated in asphalt mixtures are photocatalytic, superhydrophobic, self-cleaning, de-icing/anti-icing, self-healing, thermochromic, and latent heat thermal energy storage abilities. These abilities are developed using different materials such as nano/microparticles (including semiconductor materials and microcapsules), fibers, phase change materials (PCMs), and dyes, often using dissimilar techniques such as spray coating, volume incorporation, spreading, and asphalt binder modification. Owing to their large surface areas, road pavements are true recipients for large amounts of nano/micromaterials, and consequently, act as important “tools” to stimulate an emerging sector related to the scale of production of materials in the form of nanoparticles. Moreover, smart and multifunctional road pavements can be included in the domain of clean technology (e.g., photocatalytic pavements that promote the environmental depollution of NOx-type gases emitted as vehicle exhaust gases). In this context, they can contribute to materializing the transition to a novel socio-economic model known as “Green Recovery” that is environmentally friendly, sustainable, and inclusive. This model is a very important path toward economic and employment recovery, a vision to which many countries are strongly committed. Therefore, this work reviews new capabilities imparted to asphalt mixtures and provides recommendations.This work was supported by FCT (Fundação para a Ciência e a Tecnologia) under the framework of the Strategic Funding UIDB/04029/2020, UIDB/04650/2020, and UID/FIS/04650/2019, and the PTDC/FIS-MAC/6606/2020, PTDC/FIS/120412/2010, and PEst-OE/ECI/UI4047/2019. The first author would like to acknowledge the FCT for the Ph.D. scholarship (SFRH/BD/137421/2018) and the third author would like to thank CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico - for the PQ 1-D scholarship (308,360/2017–6)

    Características físico-quimicas de cultivares de alho (Allium sativum L.) do grupo semi-nobre, nas condições de Lavras, MG.

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    Com o objetivo de avaliar as características físico-químicas de cultivares de alhos do grupo semi-nobre conduziu-se um ensaio no Setor de Olericultura da Universidade Federal de Lavras, Lavras-MG.Suplemento. Edição de Resumos expandidos e palestras do 43. Congresso Brasileiro de Olericultura, Recife, jul. 2003
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