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It's not only the carbon in the trees Forest loss affects climate not just because of the impacts it has on the carbon cycle, but also because of how it affects the fluxes of energy and water between the land and the atmosphere. Evaluating global impact is complicated because deforestation can produce different results in different climate zones, making it hard to determine large-scale trends rather than more local ones. Alkama and Cescatti conducted a global assessment of the biophysical effects of forest cover change. Forest loss amplifies diurnal temperature variations, increases mean and maximum air temperatures, and causes a significant amount of warming when compared to CO 2 emission from land-use change. Science , this issue p. 600

AbstractIn this work, the drying step for cathodes based on carbon‐coated LiFePO4 prepared in the temperature range of 60–120 °C has been investigated in detail. The microstructure of the cathode shows a homogeneous distribution of the active material and conductive additive particles independent of the drying temperature. However, the results of impedance spectroscopy and cycling voltammetry are affected by the drying temperature. The solvent evaporation temperature, therefore, affects the polymer binder distribution and its characteristics, which include the polar phase content of the polymer and its affinity with the other components of the cathode. The discharge capacity value after 50 cycles is 120 and 81 mAh g−1 for the samples dried at 80 and 60 °C, respectively, which show the best and worst battery performance, respectively. It was concluded that carbon‐coated LiFePO4 cathodes should be prepared at drying temperatures between 80 and 100 °C for optimized performance.

This study builds a holistic, transparent life cycle assessment model of a variety of aqueous mineral carbonation processes using a hybrid process model and economic input–output life cycle assessment approach (hybrid EIO-LCA). The model allows for the evaluation of the tradeoffs between different reaction enhancement processes while considering the larger lifecycle impacts on energy use and material consumption. A preliminary systematic investigation of the tradeoffs inherent in mineral carbonation processes is conducted to provide guidance for the optimization of the life-cycle energy efficiency of various proposed mineral carbonation processes. The life-cycle assessment of aqueous mineral carbonation suggests that a variety of alkalinity sources and process configurations are capable of net CO2 reductions. The total CO2 storage potential for the alkalinity sources considered in the U.S. ranges from 1.8% to 23.7% of U.S. CO2 emissions, depending on the assumed availability of natural alkalinity sources and efficiency of the mineral carbonation processes.

Abstract The field of energy harvesting holds the promise of making our buildings “smart” if effective energy sources can be developed for use in ambient indoor conditions. Photovoltaics (PV), especially in its thin flexible form for easy integration, become a prime candidate for the aim, if tailored for low-density artificial light. We designed a test system which enabled us to measure the performance of PV devices under compact fluorescent lamp (CFL) and light-emitting diode (LED) illumination at different illuminance levels and compared polycrystalline and amorphous silicon cells with our own flexible dye solar cells (DSCs). Whereas poly-Si cells, with 15% outdoor efficiency, delivered at 200 lux under CFL only 2.8 μW/cm2 power density (and an efficiency of 4.4%), a-Si specifically designed for indoors, gave 5.9 μW/cm2 and 9.2% efficiency under the same CFL conditions (and 7.5% efficiency under LED). However, we show that the customization of flexible DSCs, by simply formulating ad-hoc less-concentrated, more transparent electrolytes, enabled these devices to outperform all others, providing average power densities of 8.0 μW/cm2 and 12.4% efficiencies under 200 lux CFL (more than quadruple compared to those measured at 1 sun), and 6.6 μW/cm2 and 10% efficiency under 200 lux LED illumination.

This work studied outdoor pilot scale production of Nannochloropsis gaditana in tubular photobioreactors. The growth and biomass composition of the strain were studied under different culture strategies: continuous-mode (varying nutrient supply and dilution rate) and two-stage cultures aiming lipid enhancement. Besides, parameters such as irradiance, specific nitrate input and dilution rate were used to obtain models predicting growth, lipid and fatty acids production rates. The range of optimum dilution rate was 0.31-0.351/day with maximum biomass, lipid and fatty acids productivities of 590, 110 and 66.8 mg/l day, respectively. Nitrate limitation led to an increase in lipid and fatty acids contents (from 20.5% to 38.0% and from 16.9% to 23.5%, respectively). Two-stage culture strategy provided similar fatty acids productivities (56.4 mg/l day) but the neutral lipids content was doubled.

This study classifies Mediterranean marine protected areas (MPAs) according to the combined result of pressure level and protection. Six major marine environment pressures were considered: pressures from fish farms, fishing, marine litter, pressures from marinas, pollution from maritime transport, and climate change. MPA protection was assessed through legal protection and management effort. Most MPA area in the Mediterranean is under relatively high pressure level and afforded low protection. Inshore areas show higher pressure levels. Five marine ecoregions, nine countries and nineteen MPA designation categories have over 50% of their MPA area under major concern. The mean number of cumulative pressures occurring in priority MPAs ranges between three and four, although the mean combined intensity of those pressures is low. However, these figures are most likely underestimated, especially for the southern Mediterranean. The most concerning pressures to MPAs regarding extent and intensity were: climate change, fishing and pollution from maritime transport.

AbstractBlack TiO2 has demonstrated a great potential for a variety of renewable energy technologies. However, its practical application is heavily hindered due to lack of efficient hydrogenation methods and a deeper understanding of hydrogenation mechanisms. Here, a simple and straightforward hot wire annealing (HWA) method is presented to prepare black TiO2 (H–TiO2) nanorods with enhanced photo‐electrochemical (PEC) activity by means of atomic hydrogen [H]. Compared to conventional molecular hydrogen approaches, the HWA shows remarkable effectiveness without any detrimental side effects on the device structure, and simultaneously the photocurrent density of H–TiO2 reaches 2.5 mA cm−2 (at 1.23 V vs reversible hydrogen electrode (RHE)). Due to the controllable and reproducible [H] flux, the HWA can be developed as a standard hydrogenation method for black TiO2. Meanwhile, the relationships between the wire temperatures, structural, optical, and photo‐electrochemical properties are systematically investigated to verify the improved PEC activity. Furthermore, the density functional theory (DFT) study provides a comprehensive insight not only into the highly efficient mechanism of the HWA approach but also its favorably low‐energy‐barrier hydrogenation pathway. The findings will have a profound impact on the broad energy applications of H–TiO2 and contribute to the fundamental understanding of its hydrogenation.

The interaction between quercetin and lipoxygenase was investigated by fluorescence spectroscopy. The analysis of the emission quenching at different temperatures revealed that the quenching mechanism correspond to a static process and, as consequence, a complex quercetin-lipoxygenase is formed. The thermodynamic parameters ΔG, ΔH and ΔS were calculated to be-32.57 kJ mol(-1),-3.21 kJ mol(-1) and 87.14 J mol(-1) K(-1) respectively, which suggest that hydrophobic forces plays a major role in the stabilization of the complex quercetin-lipoxygenase. The distance, r, between donor (lipoxygenase) and acceptor (quercetin) was calculated to be 3.84 nm based on Förster's non-radiative energy transfer theory. The results obtained from the evaluation of three dimensional florescence spectra suggest a conformational modification of the protein in the region of the coupling with quercetin.

The chemical and biological properties of the water column at a Tyrrhenian site (Isola del Giglio) were studied during a 3-year period. The results highlighted the oligotrophic features of the site, characterised by quite low concentrations of organic carbon (on average DOC 102 micromol/L and POC 9 micromol/L). Relevant bacterial biomass (on average 42.1 microg C/L) and a notable activity (in terms of frequency of dividing cells, on average more than 5%) were observed. However, remarkable changes for these parameters were seasonally recorded. The cyclic occurrence, generally during the late spring-summer period, of benthic mucilage indicated that localised distrophic processes may occur. In particular, the benthic mucilage events of 2000 and 2001 were investigated, although some comparative information was available also for 1999 and 2002. The mucilage aggregates generally showed high bacterial colonisation, which have remarkable effects on the organic matter cycle both inside the aggregates and in the surrounding seawater. During the benthic mucilage development, an increase of DOC and POC concentrations was observed (up to 129 and 18 micromol/L, respectively, in June 2000 and up to 145 and 10 micromol/L, respectively, in May and June 2001) in the water column adjacent to the bottom. However, a general decrease of the trophic value of particulate matter (in terms of C/N ratio) was also observed, especially in 2000 after the disappearance of the mucilage. The available energy and organic matter during the mucilage events led to an increased presence of bacteria in the bottom waters of the Isola del Giglio, with maximum biomass values in 2001. Similarly, the replicative activity of bacteria was higher in 2001 (frequency of dividing cells about 5% vs. 3% of 2000). The lower activity of 2000, in addition to the lower trophic value of organic matter and different environmental conditions (namely lower temperature), might be involved in the persistence of mucilage in 2000 with respect to the rapid disappearance observed in 2001.