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We investigated how a community of microbial decomposers adapted to a reference site responds to a sudden decrease in the water quality. For that, we assessed the activity and diversity of fungi and bacteria on decomposing leaves that were transplanted from a reference (E1) to a polluted site (E2), and results were compared to those from decomposing leaves either at E1 or E2. The two sites had contrasting concentrations of organic and inorganic nutrients and heavy metals in the stream water. At E2, leaf decomposition rates, fungal biomass, and sporulation were reduced, while bacterial biomass was stimulated. Fungal diversity was four times lower at the polluted site. The structure of fungal community on leaves decomposing at E2 significantly differed from that decomposing at E1, as indicated by the principal response curves analysis. Articulospora tetracladia, Anguillospora filiformis, and Lunulospora curvula were dominant species on leaves decomposing at E1 and were the most negatively affected by the transfer to the polluted site. The transfer of leaves colonized at the reference site to the polluted site reduced fungal diversity and sporulation but not fungal biomass and leaf decomposition. Overall, results suggest that the high diversity on leaves from the upstream site might have mitigated the impact of anthropogenic stress on microbial decomposition of leaves transplanted to the polluted site.

Abstract Grape pomace is a by-product of the wine making industry with great availability and energetic potential. Torrefaction is a pre-treatment that may enhance the biomass quality as a fuel, and consists in exposing the biomass to an inert atmosphere at a temperature between 200 °C and 300 °C. This study evaluates the combustion characteristics of raw and torrefied grape pomace in a thermogravimetric analyzer and in a drop tube furnace. Initially, the raw grape pomace was torrefied in an argon inert atmosphere at 260 °C. Subsequently, the combustion of the raw and torrefied grape pomace was examined in the thermogravimetric analyzer through non-isothermal runs at a heating rate of 10 °C/min from room temperature to 800 °C. Finally, the combustion of both biomass residues was evaluated in the drop tube furnace at 1100 °C. The data reported includes gas temperature, major gas species concentration and particle burnout measured along the axis of the drop tube furnace. The main conclusions of this study are (i) for the devolatilization stage, the thermogravimetric data yielded apparent activation energy values of 84.9 and 85.2 kJ mol−1, and for the char oxidation stage of 137.5 and 109.2 kJ mol−1 for the raw and torrefied grape pomace, respectively; (ii) the NOx concentrations along the drop tube furnace were always higher for the combustion of the torrefied grape pomace than for the combustion of the raw grape pomace because the former residue has a higher nitrogen content; and (iii) the burnout values along the drop tube furnace were always lower for the combustion of the torrefied grape pomace than for the combustion of the raw grape pomace because the former residue has a lower volatile content and a higher fixed carbon content.

Distributed energy resources (DERs) change the supply-demand balance of power systems. To better manage these resources, they are operated as micro-grids (MGs) in both grid-connected and standalone modes. In the presence of MGs, the decision making framework in power systems is changing from the centralized structure into the decentralized one. In such framework, modeling the operation problem of MGs with the participation in energy and reserve markets in the presence of uncertainties is considered as an important challenge. Most of the studies use probability distribution functions (PDFs) to model the uncertain parameters. In this paper, the operation problem of a grid-connected MG is modeled while the MG operator (MGO) faces with uncertainties of renewable energy sources (RESs) without considering their PDFs. For this purpose, an information gap decision theory (IGDT)-based approach is employed to model the uncertain behavior of RESs as well as to control the risk level of the MGO on the optimal scheduling of DERs. To investigate the effectiveness of the model, a modified 15-bus low voltage MG us used as a test system. The results show that optimal decisions of the risk-averse MGO are different from those of a risky one.

This work presents a crude bioethanol fueled integrated power system for backup and off-grid applications. The system is based on ethanol steam reformation to hydrogen that is used in polymer electrolyte fuel cells to produce electricity. We introduce the system design and overall system specifications, and report the experimental process of defining specifications for the produced hydrogen quality, a key variable affecting the final system cost, efficiency and durability. Results from development of individual subsystems are also presented together with discussion on the complete system integration.

Abstract This study employs the decomposition analysis of CO2 emissions for the period from 2000 to 2012. This technique computes five effects that drive changes in CO2 emissions in five subsectors of the Portuguese tourism industry. The energy over fixed capital, the capital over labour productivity, and the tourism intensity are the most important effects in accommodation, food and beverage services. The carbonisation index constitutes an important effect in transports. The capital over labour productivity intensity effect has the strongest influence, while the carbonisation index exerts a positive influence upon CO2 emissions in tour operators and travel agencies. The energy over gross fixed capital and tourism intensity effects predominate in cultural, sports and recreational services. The results of the econometric analysis further confirm the statistical significance of the aforementioned effects. Policy recommendations are provided.

Abstract The use of fossil fuel vehicles is one of the factors responsible for the degradation of air quality in urban areas. In order to reduce levels of air pollution in metropolitan areas, several countries have encouraged the use of electric vehicles in the cities. However, due to the high investment costs in this class of vehicles, it is expected that the spatial distribution of electric vehicles' adopters will be heterogeneous. The additional charging power required by electric vehicles' batteries can change operation and expansion planning of power distribution utilities. In addition, urban planning agencies should analyze the most suitable locations for the construction of electric vehicle recharging stations. Thus, in order to provide information for the planning of electric mobility services in the city, this paper presents a spatiotemporal model for estimating the rate of electric vehicles' adopters per subareas. Results are spatial databases that can be viewed in geographic information systems to observe regions with greater expectancy of residential electric vehicle adopters. These outcomes can help utilities to develop new services that ground on the rising availability of electric mobility in urban zones.

This chapter covers the interactions between the transport and routing protocols layers. The aim is to provide better planning and design for MANET (Mobile Ad hoc NETwork). Two previously proposed solutions are combined for a cross layer solution in order to ensure some QoS (Quality of Service) parameters. The first solution is called CL-TCP (cross layer TCP). It is an adaptation of the TCP congestion control mechanism with some parameters provided by the routing layer (mobility nodes and the size of routing length). The second solution is called EM-OLSR (Energy Efficiency in MANET by improving OLSR protocol), which is based on the OLSR routing protocol and adding a new energy fairness parameter to the multi-point relay (MPR) technique. The obtained cross layer solution is called CL-TCP-OLSR; varied network conditions such as the network density and the mobility of nodes are evaluated. After the evaluation of three parameters, the obtained results after evaluation are satisfactory, and they show that CL-TCP-OLSR improves TCP throughput, TCP end-to-end delay, and the energy consumption in the network.

This study breaks down carbon emissions into six effects within the current 28 European Union (EU) countries group, thereafter, they are divided into two different groups (the first 15 countries (EU-15) and the last 13 entering the EU (EU13)). Country-specific highlights are also examined. It analyses the evolution of the effects using a data span that runs from 1990 to 2014, to determine which of them had more impact on the intensity of emissions, while also breaking down the complete period into two distinct periods (before the Kyoto protocol (1990-2004) and after Kyoto (2005-2014)). In order to add more knowledge to the current literature, both the additive and multiplicative decomposition techniques were used to examine carbon dioxide (CO2) emissions and the selected six components: carbon intensity, fossil fuel consumption, energy intensity, oil imports intensity, oil dependence, and population effect. Results point to different adapting velocities for Kyoto targets and necessary compromises. The different velocities were translated into different positive and negative impacts in the change of behavior of CO2 emissions throughout Europe. A stress in the fluctuations in CO2 variations before and after Kyoto and between the two different groups of EU countries could be noticed. Moreover, energy intensity and per capita dependence of oil products were identified as the major responsible components for the total and negative changes of emissions in recent years. A decrease in total changes of emissions is observed due to the fossil fuel energy consumption effect and total petroleum products effects. It is possible to infer from here that increased renewable capacity is contributing in a positive way to eco-efficiency, and should therefore be accounted for in national policymakers' decisions in the strongest way possible. Results also seem to indicate that per capita dependence of oil products has decreased, despite oil imports intensity constancy and increased renewable capacity, however, with clear heterogeneous effects, worthy of consideration when defining policies.