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In the present work the efficiency of the fluidized bed combustion (FBC) of high-volatile fuels and the extent of volatile matter post-combustion in the splashing zone and freeboard are investigated. A typical Mediterranean biomass (pine-seed shells) has been burned in a pilot-scale bubbling FB combustor (200 kWt) at different operating conditions. Both over-and under-bed fuel feeding options have been considered. A FBC model specifically developed for high-volatile fuels has been also applied to provide a comparison with bed carbon loading, in-bed heat release and splashing region temperature experimental data. Experimental results showed that the biomass combustion efficiency is always very high as a consequence of the high reactivity of the fuel. Extensive volatile post-combustion above the bed is observed, whose extent appears to be sensitive to the over/under bed feeding option and to the excess air. Approximately 80% of the total heat is released/recirculated in the bed, the remainder leading to appreciable overheating of the freeboard with respect to the nominal bed temperature. Very low bed carbon loadings have been found. Model results compare well with the experimental temperature, heat release and carbon loading trends. However, a detailed prediction of the freeboard temperature profiles requires further improvements of the model.

This study investigates the processes that mediate the effects of framing flood risks on people's information needs. Insight into the effects of risk frames is important for developing balanced risk communication that explains both risks and benefits of living near water. The research was inspired by the risk information seeking and processing model and related models. In a web‐based survey, respondents (n = 1,457) were randomly assigned to one of three communication frames or a control frame (experimental conditions). Each frame identically explained flood risk and additionally refined the message by emphasizing climate change, the quality of flood risk management, or the amenities of living near water. We tested the extent to which risk perceptions, trust, and affective responses mediate the framing effects on information need. As expected, the frames on average resulted in higher information need than the control frame. Attempts to lower fear appeal by stressing safety or amenities instead of climate change were marginally successful, a phenomenon that is known as a “negativity bias.” Framing effects were mediated by negative attributes (risk perception and negative affect) but not by positive attributes (trust and positive affect). This finding calls for theoretical refinement. Practically, communication messages will be more effective when they stimulate risk perceptions and evoke negative affect. However, arousal of fear may have unwanted side effects. For instance, fear arousal could lead to lower levels of trust in risk management among citizens. Regular monitoring of citizens’ attitudes is important to prevent extreme levels of distrust or cynicism.

The challenge of incorporating the concept of ecosystem services in landscape planning has been widely acknowledged, yet values of ecosystem services are not well considered in current landscape planning and environmental governance. This is particularly the case when local stakeholders are strongly involved in decision making about adapting the landscape to future demands and challenges. Engagement of stakeholders introduces a variety of interests and motives that result in diverging value interpretations. Moreover, participative planning approaches are based on learning processes, implying that the perceptions of value evolve during the planning process. Current valuation approaches are not able to support such process. Therefore we argue that there is a need for a novel view on the mechanism of integrating valuation in the different stages of community-based landscape planning, as well as for tools based on this mechanism. By revisiting the original conception of ecosystem services and redefining the value of an ecosystem service as its comparative importance to human wellbeing, we develop a conceptual framework for incorporating ecosystem service valuation that captures the full spectrum of value and value changes. We acknowledge that in the social interactions during the planning process values are redefined, negotiated and reframed in the context of the local landscape. Therefore, we propose a valuation mechanism that evolves through the phases of the cyclic planning process. We illustrate the use of this mechanism by proposing a tool that supports stakeholder groups in building a value-based vision on landscape adaptation that contributes to all wellbeing dimensions.

Abstract The electrochemical response of two biologically important benzopyrazine derivative, Quinoxaline and Brimonidine (5-bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxaline-6-amine) was studied at glassy carbon electrode. Investigations were performed in acetate buffer at pH 3.6 where both compounds undergo complex electrode process which begins with quasi reversible redox process at pyrazine ring forming di-hydro derivative, which is further irreversible oxidized to hydroxyl-derivative. Cyclic voltammetry at different scan rates was employed for the determination of heterogeneous electron transfer rate constant and diffusion coefficient of the compounds. The values of electron transfer rate constant at different temperatures were used for the evaluation of thermodynamic parameters like enthalpy, entropy and Gibbs free energy changes, as well as apparent energy of activation. Computational study has been performed in order to evaluate some useful quantum chemical parameters with the aim to confirm and explain the difference in experimentally obtained kinetic and thermodynamic parameters of the investigated QUI and BRIM redox process. Results were compared with studies of similar compounds and pointed out the observed similarities and differences.

Abstract Only relying on surface information, the Deaves and Harris (DH) model was tested in predicting annual mean wind speed, Weibull distribution and energy yield at turbine hub heights of 40, 80 and 140 m. Based on 3-year (2011–2013) 10-min observations from the mast of Cabauw, the DH model was compared to the power law. The DH model was forced being applied for all stability conditions, although actually developed for the strongest neutral wind conditions (when about 75% overall wind energy may be extracted). The DH model was the finest at higher levels and its accuracy generally increased with height: at 80 m, biases of 2% (mean wind speed) and 6.06% (energy yield) were achieved, while at 140 m biases of 1% and 6.16% were obtained, respectively. Since affected by a high sensitivity to site's roughness length, an accurate assessment of this parameter proved to be main model's shortcoming. In any case, currently-achieved scores encourage further applications of the DH model, which should be deemed as a challenging wind energy research topic. Since valid over the entire boundary layer, it may be regarded as an ideal and certainly forward-looking tool for addressing modern multi-MW turbines whose hub heights steadily increase.

This chapter examines the analyses and strategies presented for each of the case studies in Chaps. 4, 6, 7, 8, 9, 10 and 11 and presents a comparison in order to draw out the main findings which may provide possible solutions for policy makers working in other regions. As explained in Chap. 1, there are a range of particular policy challenges in the urban fringe. The policies of several adjacent municipalities or local authorities may be combined and managed by an indirectly elected regional authority, while different national and EU-level sectoral and regional policies frequently interfere with each other in such areas. Problems of implementation deficits with sector-based strategies are commonplace following institutional fragmentation, calling for increased co-ordination and better integration mechanisms (Tatenhove et al. 2000).

An experimental apparatus has been developed in order to perform tests of primary fragmentation of solid fuels under severe heating conditions. The device is a modified heated strip reactor, capable to reach 2000 C in less than 0.2 s. Particles are laid on the strip and pyrolysed under inert or moderately oxidizing conditions. The char particles and their fragments, generated upon pyrolysis, can be recovered and analysed to assess the fragmentation propensity of the fuel. Some preliminary experiments have been carried out on two biomass samples in order to assess the time-temperature history of particles in the experimental apparatus. In particular biomass particles of approximately 2-3 mm have been used. The temperature of the heated strip reactor in such preliminary tests was varied between 1000 and 1600 C, while the strip nominal heating rate was kept at 10{sup 4} C/s and the holding time was set at the value of 10 s. A near infrared fast camera (38,000 frames/s) has been used to measure the temperature of the heated strip and of the particles during the tests. A heat up model was developed and validated against experimental results. The model was then used to estimate the temperature gradients across particlesmore » of biomass and of coal as well. Results show that the strip of the reactor reaches the set temperature in less than 0.2 s. When particles are laid on the strip, their bottom surface, which is in physical contact with the strip, immediately reaches the set temperature value. For 1 mm coal particles the upper surface can be considered at the same temperature as well. Under the most severe conditions tested (strip temperature of 1600 C, biomass particles of 2 mm thickness) the temperature difference between the bottom and the upper face is 200 C after 3 s and drops to 100 C after 10 s. On the whole the experimental apparatus simulates uniform heating of the particles with reasonable approximation. In the next future the apparatus will be further upgraded to operate at pressures up to 20 bars. (author)« less

ABSTRACTThis paper concludes a special series of 7 articles (4 on toxicokinetic–toxicodynamic [TK–TD] models and 3 on quantitative structure‐activity relationship [QSAR] models) published in previous issues of Integrated Environmental Assessment and Management (IEAM). The present paper summarizes the special series articles and highlights their contribution to the topic of increasing the regulatory applicability of effect models. For both TK–TD and QSAR approaches, we then describe the main research needs. The use of TK–TD models for describing sublethal effects must be better developed, particularly through the improvement of the dynamic energy budget (DEBtox) approach. The potential of TK–TD models for moving from lower (molecular) to higher (population) hierarchical levels is highlighted as a promising research line. Some relevant issues to improve the acceptance of QSAR models at the regulatory level are also described, such as increased transparency of the performance assessment and of the modeling algorithms, model documentation, relevance of the chosen target for regulatory needs, and improved mechanistic interpretability. Integr Environ Assess Manag 2019;00:000–000. © 2019 SETAC