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9 Figuras, 4 Tablas.-- Material suplementario disponible en línea en la página web del editor. Co-pyrolysis of grape seeds and polystyrene was conducted in a fixed-bed reactor, followed by an analysis of the organic phase for possible further application as a drop-in fuel. Significant positive synergistic effects were found with the addition of polystyrene (5–40 wt%) to the conventional pyrolysis of grape seeds. There was a considerable improvement in the organic phase yield, in particular, reaching values over 80 wt%, markedly higher than those obtained from conventional pyrolysis (61 wt%). Fuel properties of the bio-oil were also upgraded, with a decrease in oxygen content and an increase in the heating value. An organic bio-oil fraction with pH values ranging from 5.4 to 6.2 was obtained, reducing the issues associated with handling bio-oils obtained from common pyrolysis of lignocellulosic biomass, usually ranging pH between 2 and 3. Finally, an increment in the desired compounds, mainly aromatics, was also attained, while at the same time achieving a low content of undesired compounds, such as phenols. It was demonstrated that polystyrene can act as a H2-donor, favoring oligomerization, cyclation and hydrodeoxygenation reactions into aromatic compounds. The authors would like to thank MINECO and FEDER for their financial support (Project ENE2015-68320-R). O.S.P acknowledges the FPI fellowship (BES-2016-077750) funded by MINECO. The authors would also like to thank the Regional Government of Aragon (DGA) for the support provided under the research groups support programme. Peer reviewed

Continuous phosphorus discharges in bodies of water, generated by human activities, such as agriculture, domestic effluences or wastewater from industrial processes, produce contaminated water and eutrophication. For this reason, efficient and low-cost systems that can remove phosphorus from contaminated water are necessary. In addition, it is important to generate renewable energy such as the energy produced in biomass power plants, taking advantage of the available biomass waste in each place. When producing this renewable energy, the resulting ash is a residue that can be used for phosphorus removal by adsorption processes. Moreover, according to the concept of the circular economy, the ash waste generated in this bio energy process should be reduced as much as possible. One of the advantages of this research being that surplus phosphorus-laden ash can be reused as fertilizer in agricultural fields. Considering this, the efficiency of reed ash (RA) (Phragmites australis) has been analysed in batch experiments, as well as the effect of several parameters on the removal of phosphate, such as contact time, phosphate-ash ratio, ash dose and temperature. Significant results obtained show that RA can be used to improve water quality.

Vegetated coastal ecosystems, in particular mangroves, tidal marshes and seagrasses are highly efficient at sequestering and storing carbon, making them valuable assets for climate change mitigation and adaptation. The state of Queensland, in northeastern Australia, contains almost half of the total area of these blue carbon ecosystems in the country, yet there are few detailed regional or state-wide assessments of their total sedimentary organic carbon (SOC) stocks. We compiled existing SOC data and used boosted regression tree models to evaluate the influence of environmental variables in explaining the variability in SOC stocks, and to produce spatially explicit blue carbon estimates. The final models explained 75 % (for mangroves and tidal marshes) and 65 % (for seagrasses) of the variability in SOC stocks. Total SOC stocks in the state of Queensland were estimated at 569 ± 98 Tg C (173 ± 32 Tg C, 232 ± 50 Tg C, and 164 ± 16 Tg C from mangroves, tidal marshes and seagrasses, respectively). Regional predictions for each of Queensland's eleven Natural Resource Management regions revealed that 60 % of the state's SOC stocks occurred within three regions (Cape York, Torres Strait and Southern Gulf Natural Resource Management regions) due to a combination of high values of SOC stocks and large areas of coastal wetlands. Protected areas in Queensland play an important role in conserving SOC assets in Queensland's coastal wetlands. For example, ~19 Tg C within terrestrial protected areas, ~27 Tg C within marine protected areas and ~ 40 Tg C within areas of matters of State Environmental Significance. Using multi-decadal (1987-2020) mapped distributions of mangroves in Queensland; we found that mangrove area increased by approximately 30,000 ha from 1987 to 2020, which led to temporal fluctuations in mangrove plant and SOC stocks. We estimated that plant stocks decreased from ~45 Tg C in 1987 to ~34.2 Tg C in 2020, while SOC stocks remained relatively constant from ~107.9 Tg C in 1987 to 108.0 Tg C in 2020. Considering the level of current protection, emissions from mangrove deforestation are potentially very low; therefore, representing minor opportunities for mangrove blue carbon projects in the region. Our study provides much needed information on current trends in carbon stocks and their conservation in Queensland's coastal wetlands, while also contributing to guide future management actions, including blue carbon restoration projects.

The investigation of degradation of seven distinct sets (with a number of individual cells of n $ 12) of state of the art organic photovoltaic devices prepared by leading research laboratories with a combination of imaging methods is reported. All devices have been shipped to and degraded at Risø DTU up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. Imaging of device function at different stages of degradation was performed by laser-beam induced current (LBIC) scanning; luminescence imaging, specifically photoluminescence (PLI) and electroluminescence (ELI); as well as by lock-in thermography (LIT). Each of the imaging techniques exhibits its specific advantages with respect to sensing certain degradation features, which will be compared and discussed here in detail. As a consequence, a combination of several imaging techniques yields very conclusive information about the degradation processes controlling device function. The large variety of device architectures in turn enables valuable progress in the proper interpretation of imaging results—hence revealing the benefits of this large scale cooperation in making a step forward in the understanding of organic solar cell aging and its interpretation by state-of-the-art imaging methods.

By means of a case study, we examine the effect of size on the estimated weight and cost of an advanced wind energy conversion system, the diffuser-augmented wind turbine (DAWT) concept. Preliminary designs are described for three DAWT sizes (ratings) in each of three construction approaches: all-aluminum, ferrocement, and a hybrid fiberglass reinforced plastics (FRP) diffuser shell on an aluminum frame. Common design criteria are employed in designs for these three materials. Installed cost estimates are generated by professional industrial estimators. Excluding the foundation, it is concluded that for geometrically similar DAWTs the weight-to-power ratio varies approximately as the rotor diameter to the one third power, over a 4 to 1 change in rotor diameter, 2.7–11 m (9–36 ft). Futhermore, because the total direct production cost of these various DAWT units and designs proves to change by about D1.5, the cost-to-power ratio is approximately proportional to D−.5 and the cost/weight ratio varies as D−1/6. Therefore, for the investigated DAWT unit ratings between 5 and 200 kW, the larger units appear increasingly to become more efficient structures with apparently lower specific costs (dollars per kW) for each of three candidate construction approaches.

Long-duration gamma-ray bursts (GRBs) release copious amounts of energy across the entire electromagnetic spectrum, and so provide a window into the process of black hole formation from the collapse of massive stars. Previous early optical observations of even the most exceptional GRBs (990123 and 030329) lacked both the temporal resolution to probe the optical flash in detail and the accuracy needed to trace the transition from the prompt emission within the outflow to external shocks caused by interaction with the progenitor environment. Here we report observations of the extraordinarily bright prompt optical and gamma-ray emission of GRB 080319B that provide diagnostics within seconds of its formation, followed by broadband observations of the afterglow decay that continued for weeks. We show that the prompt emission stems from a single physical region, implying an extremely relativistic outflow that propagates within the narrow inner core of a two-component jet.

Abstract Pyrolysis is currently being considered as an alternative method of treating sewage sludge. It yields residual oils and gases, which can be used as fuels, and a solid which can either be burned or physically activated with air or CO 2 . The aim of this work was to study the influence of different pyrolysis conditions (e.g. temperature and heating rate) on the reactivity in air and in CO 2 of carbonaceous materials obtained from these types of residues. An anaerobic sewage sludge produced in a Spanish urban waste water treatment plant, containing 5 wt.% moisture after air-drying, was pyrolyzed in an electrical laboratory furnace under different pyrolysis conditions. Non-isothermal reactivities (up to 1100°C) in air and in CO 2 of the carbonaceous materials obtained after pyrolysis were performed in a thermobalance. The TG and DTG curves obtained from these experiments are discussed.