Photocatalytic and thermochromic materials applied to road engineering

[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]

Review on the incorporation of phase change materials (PCM) into asphalt mixtures to mitigate urban heat Island

Serious environmental problems are attributed to the uncontrolled growth of cities. Usually, highly populated areas suffer from soil sealing caused by the construction of infrastructure, such as road pavements and buildings. Regarding the Transportation Engineering, the most common material applied in road pavements is bitumen as binder constituent. Usually dark-coloured, the surface temperature of asphalt pavements may reach values higher than 60 °C during summer. This fact can significantly contribute to the formation of thermal cracks and deformations in asphalt binders and, in large urban centres, promote the formation of warmer microclimates since all the accumulated heat is released to the surrounding environment. The formation of Urban Heat Islands (UHI), a type of microclimate that arises from the increase in temperature of a location that does not match the region, caused by anthropic changes, for some time now, is a problem that has attracted a range of research to minimise harmful effects caused to the environment. Some of the most promising studies to decrease the temperature of pavements are using Phase Change Materials (PCM). PCM are materials that can accumulate a large amount of thermal energy and are widely used in the textile industry, smart tissues, and construction, improving thermal comfort. PCM can minimise the problems arising from seasonal temperature variations when used in conjunction with asphalt materials. In this work, a review was made about which types of PCM are mainly used to achieve a significant decrease in pavement temperature—evaluating the material's thermal performance and the most used strategies to avoid its leakage. A systematic review of recent papers published in peer-reviewed journals (available in the Scopus database) involving asphalt mixtures with phase change materials revealed that the most used type of PCM is polyethylene glycol (PEG). Asphalt mixtures containing PCM generally have lower mechanical performance than conventional asphalt mixtures. There are problems related to leaking the material into the asphalt, sometimes reaching the soil and possibly causing contamination. On average, the temperature values decrease 4 °C, in some cases reaching 9 °C of difference, compared to conventional asphalt-based binders. To avoid leaking of this material, the most applied strategy is the PCM encapsulation within particles composed of silicon dioxide (SiO2) or polyacrylamide (PAM). According to the literature surveyed, it can be concluded that incorporating PCM into asphalt pavements can mitigate the formation of UHI acting as a thermoregulation factor, with acceptable mechanical and improved environmental performance

Evaluation of air cleaning using functionalized asphalt mixture sprayed with TiO 2 nanoparticles

[Excerto] Photocatalytic asphalt mixtures have gained attention as a possible alternative to mitigate the air pollution in urban areas. The asphalt surface when functionalized with nano-TiO2 can reduce nitrogen oxides (NOx), a harmful pollutant emitted by vehicles that contributes to problems such as acid rain and public health concernsCT/MCTES sponsored this research by the projects NanoAir PTDC/FISMAC/6606/2020, MicroCoolPav EXPL/EQU-EQU/1110/2021 and UIDB/04650/2020, under the R&D from ISISE (UIDB/04029/2020) and the ARISE (LA/P/0112/2020). Also, the second and third authors would like to acknowledge the FCT for funding PRT/BD/154269/2022, 2022.00763.CEECIND, respectively

Mitigation of urban heat island effects by thermochromic asphalt pavement

Asphalt road pavements are usually dark and, consequently, have a low albedo. Therefore, they absorb energy as heat, increasing the Urban Heat Island (UHI) effect, which impacts the environment, energy consumption, and human health. Through the functionalization with thermochromic materials (TM), this work aims to develop a smart asphalt pavement able to change its surface color, increasing the reflectance, and thus mitigate this phenomenon. To achieve this goal, asphalt substrates were functionalized by a surface spray coating of a thermochromic solution (TS) containing aqueous solution of thermochromic microcapsules (thermocapsules), dye, and epoxy resin. To evaluate the functionalization features, Fourier Transform Infrared Spectroscopy (FTIR), and Thermal Differential test (TDT) with cyclic temperature variation were performed in the functionalized asphalt binder. Moreover, Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectrometry (EDS), a Quick Ultraviolet Accelerated Weathering Test (QUV) with Colorimetry test, and an adaptation of the Accelerated Polishing Test (APT) were performed on the functionalized asphalt mixture. The results indicate that the functionalization of asphalt substrates with TS exhibits a reversible color-change ability, higher luminosity values when subjected to temperatures above 30 C, and wear resistance

Misturas asfálticas inteligentes: mito ou realidade?

A finalidade geral dos pavimentos rodoviários consiste na capacidade de resistir ao tráfego rodoviário e as ações meteorológicas, garantindo condições de rolamento seguras e confortáveis, com o menor dispêndio possível de recursos e danos sobre o meio ambiente. Um pavimento rodoviário é considerado inteligente quando possui funcionalidades adicionais ou capacidade de reagir a um estímulo externo. Estas aptidões podem ser incorporadas através da utilização de diversos materiais, por exemplo: nano/micropartículas (semicondutores e microcápsulas), materiais de mudança de fase, corantes e fibras. Dentre as novas capacidades, é possível destacar: fotocatálise, superhidrofobicidade, autolimpeza, degelo/anti-gelo, autorreparação, termocromismo e armazenamento de energia térmica latente. Algumas destas novas aptidões resultam da implementação de técnicas como: modificação de ligante asfáltico, revestimento por pulverização, espalhamento e incorporação volumétrica de componentes. Este trabalho revê as novas capacidades conferidas às misturas asfálticas, expõe informações sobre métodos de funcionalização, ensaios, materiais empregados e resultados e fornece recomendações para trabalhos futuros.The purpose of road pavements is to withstand road traffic and weather loads, while ensuring safe and comfortable driving conditions with the least possible expenditure of resources and damage to the environment. A road pavement is considered smart when it has additional abilities or capacity to react to an external stimulus. These abilities can be incorporated through various materials: nano/microparticles (semiconductors and microcapsules), phase change materials, dyes, and fibers. Among the new abilities added to asphalt mixtures are photocatalysis, superhydrophobicity, self-cleaning, de-icing/anti-icing, self-healing, thermochromism, and latent heat thermal energy storage. Some of these new capabilities result from different techniques, such as asphalt binder modification, spray coating, spreading, and volume incorporation of components. The present work reviews the new abilities conferred to asphalt mixtures, exposes the information about functionalization methods, tests, materials used and results, and provides recommendations for future work.Este trabalho foi apoiado pela Fundação para a Ciência e a Tecnologia (FCT) no âmbito dos projetos do Financiamento Estratégico UIDB/04650/2020, do projecto MicroCoolPav EXPL/EQU-EQU/1110/2021, e do projecto NanoAir PTDC/FISMAC/6606/2020. Os autores também agradecem pelo financiamento dos projetos MLC-0191-00144.01.00/22 (Edital Mulheres na Ciência Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico Funcap) e Processo 404978/2021-5, Chamada CNPq/MCTI/FNDCT Nº 18/2021 - Faixa B - Grupos Consolidados Conselho Nacional de Desenvolvimento Científico e Tecnológico CNPq)

Práticas e benefícios da inovação e sustentabilidade na gestão de projetos no contexto das PME

Mestrado em Gestão de Projetos de EngenhariaThis research aims to identify practices that help to ensure sustainability and innovation through Project Management (PM) within Small and Medium-Sized Enterprises (SMEs). Although PM has been developed in the second half of the 20th century, project-based economic activity has increased, turning it into a vehicle for implementing sustainability and innovation. A Systematic Literature Review (SLR) was conducted, considering articles in the main databases to understand: which are these practices, the evolution of this theme over the years, and the main related journals. In addition, it was also proposed to identify the benefits obtained by those who have made use of these types of practices. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 methodology was used to help select the articles with the greatest contributions among those identified in the databases. In total, 86 sustainable practices, 166 innovative practices and 61 benefits were identified. The practices and benefits were segmented into categories according to the subject they are most related to. Thus, the sustainable practices were divided according to the three dimensions of the Triple Bottom Line (TBL); the innovative practices were divided into thirteen categories; the benefits were segmented into seven categories. The most frequently mentioned sustainability-related practice was ‘Implementing waste management’; the most frequently mentioned innovation-related practice was 'Diffusing and sharing information, ideas and knowledge’. Concerning the benefits achieved, the categories with the highest number of benefits are those related to the organization and competitive advantage. Finally, a bibliometric analysis was carried out taking into consideration the bibliometric data of the main articles related to this theme. With the support of the VOSviewer software, the main groups of themes and authors with the strongest network link in terms of authorship and citations were identified and analyzed.Esta pesquisa visa identificar práticas que ajudem a assegurar a sustentabilidade e a inovação através da gestão de projetos (PM) de pequenas e médias empresas (SMEs). Embora a gestão de projetos tenha sido desenvolvida na segunda metade do século XX, a atividade económica orientada para projetos está a aumentar, tornando-a um veículo para a implementação da sustentabilidade e da inovação. Foi realizada uma revisão sistemática da literatura, considerando os artigos das principais bases de dados para compreender: quais são estas práticas, a evolução deste tema ao longo dos anos, e as principais revistas relacionadas. Além disso, foram também identificados benefícios obtidos por aqueles que fizeram uso deste tipo de práticas. A metodologia Principais Itens para Relatar Revisões Sistemáticas e Meta-análises (PRISMA) 2020 foi utilizada para ajudar a selecionar os artigos com maiores contribuições entre os identificados. No total, foram identificadas 86 práticas sustentáveis, 166 práticas inovadoras e 61 benefícios. As práticas e benefícios foram segmentados em categorias de acordo com os assuntos com os quais estão mais relacionados. Assim, as práticas sustentáveis foram divididas de acordo com as três dimensões do "tripé da sustentabilidade" (TBL); as práticas inovadoras foram divididas em treze categorias; os benefícios foram segmentados em sete categorias. A prática relacionada com a sustentabilidade mais frequentemente mencionada foi a gestão de resíduos; a prática relacionada com a inovação mais frequentemente mencionada foi a difusão e partilha de informação, ideias e conhecimentos. Quanto aos benefícios alcançados, as categorias com maior número de benefícios são as relacionadas com a organização e a vantagem competitiva. Finalmente, foi realizada uma análise bibliométrica tendo em consideração os dados bibliométricos dos principais artigos relacionados com este tema. Com o auxílio do software VOSviewer, identificou-se e analisou-se os principais grupos de temas e autores com a mais fortes redes de ligação em termos de autoria e citações

PHYSIOLOGICAL RESISTANCE OF COMMON BEAN LINES TO \u3ci\u3eSclerotinia sclerotiorum\u3c/i\u3e

INTRODUCTION. White mold (WM), caused by the fungus Sclerotinia sclerotiorum, is a serious constraint of common bean during the fall-winter season in Brazil. The most commonly used control measure is fungicide application. However, the high cost and the potentially deleterious effects on human health and environment have motivated the search for new options of WM management. Genetic resistance is a key component of the WM management, because it is easier for farmers to adopt and is environmentally safe. Since 2008, we have screened common bean lines/cultivars for WM resistance from the field trials named Value for Cultivation and Use (VCU) conducted under WM pressure. The lines screened in these trials have been developed by Federal University of Viçosa, Federal University of Lavras, EPAMIG and Embrapa Rice and Beans. Beginning in 2015, we have evaluated the genotypes screened in the VCU trials in comparison to three WM-resistant checks (A195, G122, and Cornell 605) in advanced field trials, straw and/or detached leaflet tests. Here, we present results from the straw and the detached leaflet tests to assess physiological resistance of lines/cultivars originally screened for resistance to foliar diseases and high yield

Teores de pigmentos, fluorescência da clorofila <em>a</em> e índice SPAD em cultivares de girassol sob regimes hídricos

O girassol (Helianthus annuus L.) é uma espécie vegetal que apresenta inúmeras aplicações na atualidade, sendo considerada uma das plantas que apresenta um potencial máximo de sua produção. Objetivou-se com este trabalho avaliar aspectos fotossintéticos de cultivares de girassol, submetidas a diferentes regimes hídricos. O trabalho foi realizado em casa de vegetação, nas instalações pertencentes ao Departamento de Engenharia Agrícola da UFCG, conduzido em delineamento inteiramente casualizado em esquema fatorial 3 x 4 (três cultivares e quatro níveis de irrigação) com quatro repetições. Foram utilizados vasos com capacidade para 100 L, tendo-se o conteúdo de água do solo  monitorado diariamente por meio de uma sonda de capacitância, modelo DIVINER 2000®, segmentada nos tratamentos com 100% da capacidade de campo (CC). Foram avaliadas as características: fluorescência da clorofila a, teores de clorofila a, b e total, e índice relativo SPAD. Houve diferença estatística entre as cultivares para o índice relativo de clorofila e o teor de carotenoides, e entre os regimes hídricos para os teores de clorofila b e clorofila total. Houve correlação entre o índice de clorofila (SPAD) e o teor de clorofila total. Os regimes hídricos não alteraram a fluorescência e o teor da clorofila a, entretanto, alteraram os teores de clorofila b e total em plantas de girassol