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Abstract In order to develop a deeper understanding of the behaviour of commercial automotive lithium-ion pouch cells under short-circuiting conditions, two scenarios were experimentally investigated and compared. Firstly, experiments were conducted by internally shorting 15 Ah cells by full nail penetration using three different nail materials; copper, steel and plastic. A second set of experiments involved externally shorting the cell tabs using an external circuit with a range of resistance values. In both scenarios the cell electrical and thermal response were determined by the shorting resistance. In the case of nail penetration there was a clear distinction between the outcome of the conducting and non-conducting nails, although the outcome using conducting nails suffered from poor reproducibility. The poor reproducibility was attributed to the variation in the contact resistance between the nail and the cell layers. Correlating the outcome of both tests can be used to estimate the shorting resistance and construct the current profile during nail penetration test.

The technological development of preparing bio-oil from low-temperature hydrothermal conversion of agricultural and forestry waste has positive significance for alleviating the shortage of oil energy supply and reducing environmental pollution. This paper selects typical oxides (Al2O3, CeO2, MgO, SiO2, TiO2, and ZnO) as catalysts to set up a low-temperature (220 °C) hydrothermal conversion process of cotton stalk containing pretreatment processes including chopping. For moderate amplification estimation, lab-scale experimental data is used as a benchmark for calculation, and the functional unit for this study is set to be a 1 kg bio-oil product. The results suggest that the cerium dioxide-involved process with the highest bio-oil yield and highest synthetic consumption, and the silica-involved process with the lowest bio-oil yield, caused the highest environmental impact, resulting in greenhouse gas (GHG) emissions of 67.729 kg CO2e/kg and 60.001 kg CO2e/kg, respectively. It indicates that catalysts need to consider the balance between synthetic consumption and catalytic performance. Magnifying lab-scale data to an industrial scale using scale-up frameworks introduces a low model uncertainty, as the practical value had little effect on the overall evaluation results. However, existing equipment data should be used to reduce the uncertainty of the model itself. The environmental sustainability of bio-oil production by low-temperature hydrothermal liquefaction still needs to be improved, especially by catalyst recovery and bio-oil yield improvement.

A simple and fast, but sensitive TLD method for the measurement of energy and homogeneity of therapeutically used electron beams has been developed and tested. This method is based on the fact that when small thicknesses of high-Z absorbers such as lead are interposed in the high-energy electron beams, the transmitted radiation increases with the energy of the electron beams. Consequently, the ratio of readouts of TLDS held on the two sides of a lead plate varied sharply (by factor of 70) with a change in energy of the electron beam from 5 MeV to 18 MeV, offering a very sensitive method for the measurement of the energy of electron beams. By using the ratio of TL readouts of two types of TLD ribbon with widely different sensitivities, LiF TLD-700 ribbons on the upstream side and highly sensitive CaF2:Dy TLD-200 ribbons on the downstream side, an electron energy discrimination of better than +/- 0.1 MeV could be achieved. The homogeneity of the electron beam energy and the absorbed dose was measured by using a jig in which the TLDS were held in the desired array on both sides of a 4 mm thick lead plate. The method takes minimal beam time and makes it possible to carry out measurements for the audit of the quality of electron beams as well as for intercomparison of beams by mail.

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.

Abstract The essay stages the law at the intersections between the humanities, technology, and the production of digital space. Interactions like these are relevant in the present age, where humankind is outcompeting natural resources and changing the earth. The Anthropocene is an epoch of environmental crisis; despite this, we turn such a crisis into a process of sublimation servient to the control of the earth. Blurring the divide between the digital and the human is functional to such a process. The strategic use of the law makes climate-change policies compatible with global markets. Assuming that manufacturing digital spaces is useful to this end, the essay focuses on multimedia games. Blending real-word performances with internet- and media-related contents, they are functional to sublimation, convincing us that we can tackle climate change without rearranging our economic paradigms.

In this article we present various issues that need careful design for the successful implementation of OFDMA-based multihop cellular networks which need incorporation of relay terminals. The first issue we present is synchronization. We show that it is not a problematic issue for infrastructure-based relaying, where the relay is deployed by a system operator at strategic points in the cell. Second, we focus on the advantage of adaptive relaying and provide a frame structure to enable adaptive relaying in a cellular network operating according to the IEEE 802.16e standard. The third issue we present is related to hardware implementation aspects. Hardware performance and resource usage analysis will show that cooperative diversity schemes increase hardware resource usage and power/energy consumption at mobile terminals. The last issue we present is within the context of link layer ARQ, where we propose a novel retransmission method, named local retransmission-ARQ (LR-ARQ), which is designed to take advantage of the multihop nature of the cellular network. Practically, we show that LR-ARQ improves performance with respect to its single-hop counterpart in terms of cell latency, goodput, and throughput.

Global climatic energy balance has been increasingly altered by massive emissions of greenhouse gases (GHGs), such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), leading to a variety of natural disturbances in terrestrial ecosystems. Further, the increasing use of fossil fuels and the looming climate crisis have created an unprecedented urgency for the development of a biobased circular economy. Therefore, production of biofuels from plant biomass is currently seen as a promising source of renewable energy, ensuring sustainable development with minimal carbon footprint. Soil acidification is considered one of the major obstacles to crop production and a significant source of GHGs emissions, especially N2O, because acidification changes the physicochemical and biochemical properties of the soil. Dolomite (DM) is the most widely used countermeasure to neutralize soil acidity to improve crop productivity and control net fluxes of GHGs. Nevertheless, the extent of GHG emissions following the application of DM under different environmental conditions is still unclear. Therefore, in this context, we conducted a meta-analysis using 32 peer-reviewed publications to determine the effects of DM, climate zones, and soil properties on GHGs emissions. The results of the current meta-analysis show that DM application significantly increased CO2 emissions (30.34 %) and CH4 emissions (4.91 %), but reduced N2O emissions by 54.88 %. A significant effect of DM (>10 t ha−1) on CO2, CH4, and N2O emissions was also observed. Increasing soil pH increased CO2 and N2O emissions by 188.34 % and 49.78 %, respectively, while reducing CH4 emissions by 81.94 %. Most importantly, WFPS, soil textural class, soil C:N ratio, and climate zones were identified as key edaphic factors affecting the GHG emissions following the application of DM. Overall, this meta-analysis fills in the gaps regarding the impact of the application of DM on GHGs emissions in different climates, soil properties, and experimental conditions. In ...

Abstract The voltammetric response of microparticulate deposits resulting from solvent evaporation of ethanolic extracts of mangrove sediments in contact with aqueous acetate buffer is hereby described. Dated sediment cores sampled from the Peruvian mangrove system (“Manglares de Tumbes” National Sanctuary) presented voltammetric responses dominated by oxidative signals of organic components that exhibit significant variations depending on the depth. Voltammetric data allowed for the definition of electrochemical indexes representative of the electrochemically oxidable organic matter fraction. These electrochemical indexes were fEAOM (for the total amount of organic matter being electrochemically active), fEROM (for the fraction of organic matter electrochemically oxidizable in reversible form), fRDOX (for the proportion between the fractions of electrochemically active organic matter which is in an oxidized state and in a reduced state) and fROS (capability for reaction with reactive oxygen species), while the spectroscopic index A1650/A3400 (as a proxy analogous to fRDOX) was also applied. The mangrove forest presents a higher oxidized fraction of the electrochemically active organic matter, as confirmed by additional data obtained from infrared spectroscopy. These results indicate that the described electrochemical indexes may provide insights on organic matter degradation by oxidative processes in addition to chemical analyses of coastal vegetated systems that are currently used, such as mangrove wetlands.