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Abstract MCM-22 zeolite samples, having different Si/Al ratios, have been studied for the fast-pyrolysis of acid-washed wheat straw at two catalytic pyrolysis temperatures aimed to the production of partially upgraded bio-oil. The best combination of bio-oil deoxygenation activity and energy yield is obtained when the catalytic bed was operated at 450 °C using the MCM-22 sample with the lowest Al content (Si/Al = 40). Interestingly, the increase in the reaction temperature results in a lower amount of coke deposited over the zeolite. On the other hand, reducing the zeolite Si/Al ratio had a negative effect as a higher concentration of acid sites promotes non-desired reactions: severe cracking of the bio-oil vapours, leading to the enhanced production of gaseous hydrocarbons, and coke formation. Coke produced over MCM-22 zeolite exhibits high oxygen content, whereas the bio-oil fraction presents a high concentration of oxygenated aromatics. These results denote the limited aromatization activity of MCM-22 zeolite for producing aromatic hydrocarbons, in particular when compared with ZSM-5, being of interest for the selective production of phenolic compounds by biomass catalytic pyrolysis.

Abstract Sedimentological, limnological and palynological analyses of a sediment core from a lowland site in West-Java, Indonesia, provide a detailed palaeoenvironmental record for the Late Glacial and the Holocene. The record suggests open vegetation under inferred drier climatic conditions for the Late Glacial. However, there is no unequivocal evidence for cooler conditions at this time. The onset of the Holocene coincides with a change to more humid climatic conditions, with the development of a fern-rich closed forest vegetation type. Dramatic changes in diatom community composition provide a striking record of habitat change associated with lake shallowing, but this process appears to be a result of basin in-filling rather than variations in precipitation/evaporation balance associated with climatic fluctuations. Evidence for human impact on the vegetation development is restricted to the last few hundred years.

Capítulos en libros info:eu-repo/semantics/publishedVersion

Abstract Buildings consume vast amounts of energy and pollute the environment in various ways. Facade is a part of building's architecture that can play a significant role in reducing energy consumption, as well as alleviating its negative environmental effects. Although using smart materials in buildings' facades can help dramatically to attain the mentioned goals, very limited studies have been conducted regarding the mentioned issues. Moreover, existing studies have investigated only a few number of smart materials simultaneously. Therefore, this research aims to conduct a wider study, identify and prioritize the most suitable building facade's smart materials according to Sustainable Development Goals (SDGs) for Shiraz, Iran. Friedman test and Analytical Hierarchy Analysis (AHP) were used to analyse data using SPSS and Expert Choice software, respectively. Produced results illustrated that “Photovoltaic materials”, “Thermochromic materials” and “Photostrictive materials” were the best alternatives for using in building's facade. Results obtained by this research can help the building industry to move through sustainability.

Combined conduction–convection–radiation heat transfer is investigated numerically in a micro-channel filled with a saturated cellular porous medium, with the channel walls held at a constant heat flux. Invoking the velocity slip and temperature jump, the thermal behaviour of the porous–fluid system are studied by considering hydrodynamically fully developed flow and applying the Darcy–Brinkman flow model. One energy equation model based on the local thermal equilibrium condition is adopted to evaluate the temperature field within the porous medium. Combined conduction and radiation heat transfer is treated as an effective conduction process with a temperature-dependent effective thermal conductivity. Results are reported in terms of the average Nusselt number and dimensionless temperature distribution, as a function of velocity slip coefficient, temperature jump coefficient, porous medium shape parameter and radiation parameters. Results show that increasing the radiation parameter $$(T_{r})$$ and the temperature jump coefficient flattens the dimensionless temperature profile. The Nusselt numbers are more sensitive to the variation in the temperature jump coefficient rather than to the velocity slip coefficient. Such that for high porous medium shape parameter, the Nusselt number is found to be independent of velocity slip. Furthermore, it is found that as the temperature jump coefficient increases, the Nusselt number decrease. In addition, for high temperature jump coefficients, the Nusselt number is found to be insensitive to the radiation parameters and porous medium shape parameter. It is also concluded that compared with the conventional macro-channels, wherein using a porous material enhances the rate of heat transfer (up to about 40 % compared to the clear channel), insertion of a porous material inside a micro-channel in slip regime does not effectively enhance the rate of heat transfer that is about 2 %.

Abstract The use of biomass derived pyrolysis oils, bio crude oil (BCO), in diesel engine requires deep modifications to the engine, such as the adoption of dual fuel systems and pilot injection: BCO/diesel emulsions are expected to significantly reduce the need for these adaptations. This paper describe the effects of various BCO/diesel emulsions on the injection systems of different diesel engines. Materials used for injectors’ nozzles and needles are investigated and compared. The issue of the erosion and/or corrosion of the injector nozzle is examined, and dedicated tests have been carried out. The experimental results suggested that corrosion accelerated by the high velocity turbulent flow in the spray channels is the dominant factor. A stainless steel nozzle has been built and successfully tested. Long term validation is however still needed.

Hybrid electrochromic (EC) devices present an interesting configuration in which the advantage of both solid-state and liquid-based devices can be combined in order to optimize the device performances. In this configuration, a solid-state EC material is combined with a redox couple dissolved in the electrolyte. The redox electrolyte offers an unlimited charge capacity, thus allowing to fully exploit the electrochromic properties of the EC material. Here, we present a thiolate/disulphide (T/T) redox couple as a new redox shuttle for EC devices. In order to transfer the advantages of the redox couple to a solid state device, it was combined with a fully transparent thermally curable vinyl-acetate polymer. The obtained EC device was compared with that based on I/I showing higher transparency in the visible region of the solar spectrum and higher coloration efficiency. Most interestingly, the device based on T/T shows a slower self-bleaching process and it only loses 30% of its coloration after 1 h at open circuit. Such characteristic represents a great advantage for smart windows applications since it is not necessary to apply potential to maintain the device coloration, thus allowing a great energy saving.