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Abstract Performance of wood gasification genset is sensitive to the moisture content in the feedstock and the electrical load (demand of users). This study investigates the influence of these process parameters on the electrical efficiency of the genset (ηglobal), the electrical engine efficiency (ηengine), the cold gas efficiency (CGE), and the syngas composition. Experimental tests were carried out by varying the moisture content from 11% to 23% and the electrical power from 4.7 kW to 12.8 kW on a commercial gasifier equipped with precise measuring tools. The increase of the performance when the electrical load is increased or when the moisture content in the wood chips is decreased is both quantified and discussed. Such behaviour was mainly explained by differences in engine filling rates and reactor temperatures.

Abstract Geodiversity and geoheritage studies are multidisciplinary, drawing from all sides of geosciences and extending them into the humanities, geoarchaeology, spatial planning, territorial and risk management, economics, tourism, or culture using integrated and interdisciplinary research approaches. During the last three decades, geodiversity and geoheritage research experienced a considerable growth that confirms both scientific and public relevance of these topics. In this introductory text, a brief review of current literature is presented and the importance of geodiversity and geoheritage for sustainable development, geohazard resilience and associated themes is discussed. Last, but not least, the aims and structure of this volume are outlined.

Abstract Thermal cross-linking in presence of residual solvent dimethylsulfoxide without any addition of cross-linker molecules is described. This elegant method increases spectacularly the mechanical and hydrolytic stability of sulfonated aromatic polymers (SAP), making them suitable for use in liquid water also at 145 °C. Data on water uptake, mechanical properties and proton conductivity are presented and discussed from a bond energy point of view. The developed method is also inexpensive, being incorporated in the normal membrane casting procedure. This opens new horizons and hitherto conventionally disregarded SAP membranes should be reconsidered as fuel cell membranes.

Electrochemical capacitors, called supercapacitors (SCs) or ultracapacitors, are devices conveniently used for embedded electrical energy management owing to their huge capacitance, low internal resistance and flexible control through power electronic conversion. This paper proposes a main power supply of hybrid Wind Generator (WG)–SC within the train station for feeding the traction onboard SC through specified limited feeding transit durations. Onboard SCs provide the train with the requested start–up self–energy. The hybrid WG–SCs system is an environmental–friendly source that enables the independency on national grid and guarantees an efficient bidirectional power transfer for energy management with enhanced dynamic performance. Therefore, the dynamic modelling and the experimental analysis of the modern hybrid WG–SCs used for managing the charge/discharge operation of SCs at Unity Power Factor (UPF) mode are presented. For this purpose, the Port–Controlled Hamiltonian (PCH) methodology is deduced and explicitly presented. Simulation results, via MATLAB™, reveal that the proposed PCH control methodology can be successfully implemented to ensure acceptable system dynamic behavior. Numerical results are validated with experimental measurements to investigate the significance of the PCH approach for the energy management operation in eco-tractions.

Since the industrial revolution, the financial sector has become a significant claimant toward the growth of human society. However, supporting the adverse environmental projects in financial terms has raised several queries about creating a direct linkage between financial market products and the environment.This research examines the nexus between sustainability, green innovations, financial technologies (FinTech), financial development, and natural resources for BRICS economies during 2000–2019. Using the Method of Moments Quantile Regression (MMQR), the results show that FinTech and natural resources adversely impact environmental sustainability across all three ranges of quantiles (0.10th-0.30th, 0.40th-0.60, and 0.70th-0.90th).Conversely, green innovations and financial development promote environmental sustainability across lower to higher-order quantiles (0.10th-0.90th), while economic growth contributes to higher emissions at major quantiles. Similar findings are endorsed using alternative estimators and suggest practical policy implications.

AbstractWe report on the synthesis, optical properties and energy‐transfer features of a series of transition‐metal‐containing complexes and dyads, based on a pre‐organised truxene scaffold. In this series, the [Ru(bpy)3]2+ and [Os(bpy)3]2+ photoactive terminals are coupled to the bridging aromatic truxene core through rigid ethynyl linkers. The photoinduced energy‐transfer processes taking place from the Ru‐ to the Os‐based levels, and from the truxene bridging ligand to the terminal‐metal chromophores are studied and the pathways and mechanisms are discussed. The photoinduced energy‐transfer process observed in the dyad proceeds rapidly through: i) an efficient 1L→1Os direct energy transfer followed by intersystem crossing to 3Os, and ii) a fast 1L→1Ru energy‐transfer step and subsequent intersystem crossing to 3Ru followed by a 3Ru→3Os energy‐transfer process. The first 1L→1Os and 1L→1Ru steps are controlled by a dipole–dipole interaction (Förster mechanism), whereas the subsequent 3Ru→3Os step proceeds by means of a long‐range (≈24 Å) through‐bond mediated Dexter mechanism, facilitated by the conjugation along the bpy‐truxene‐bpy molecular axis.

Abstract Charcoal seems one of the most promising bio-reducer because of its high coke replacement ratio in blast furnaces. Nevertheless, biochar materials are subject self-combustion during storage, handling and transport, and need to be studied in order to understand and limit these phenomena. Heat-based methods: were employed to compare and determine the self-ignition parameters of four types of fresh biochar ( Quercus pubescens , Cyclobalanopsis glauca , and Trigonostemon huangmosun , Bambusa vulgar ) that are used as bio-reducers in the silica industry. This study assumed that spontaneous combustion arises from exothermic oxygen chemisorption to fresh biochar surface. Sample mass, heat flow and CO 2 desorption were measured. The weight increased very rapidly as soon as the gas stream was changed from N 2 to air accompanying the heat generation for each material. Desorption isotherms were found to depend on the nature of the feedstock confirming that bamboo biochar was the most reactive one under air exposure.

Abstract The growing interest in syngas production from biomass has extended research towards solar-driven pyrolysis taking place at high temperature and heating rate, due to its high efficiency and environmental advantages. The aim of this work is to experimentally study and compare the effect of pellet size (5, 10 and 15 mm height) on product yields (liquid, char and gas), gas composition (H2, CO, CO2, CH4) and tar secondary reactions during fast solar pyrolysis of sawdust pellets (800, 1200 and 1600 °C and heating rates of 10 and 50 °C/s). Additionally, the influence of pellet height on syngas quality is analyzed by parameters such as H2/CO, CH4/H2 ratios, mechanical gas efficiency and carbon conversion efficiency, focused on methanol production. An analysis based on characteristic times and dimensionless numbers is also performed to estimate the rate-controlling phenomena. Experimental results showed that, for temperatures below 1200 °C, there were no significant differences in the gas yield for the three pellet heights. However, the gas product distribution was influenced by the pellet size even at 800 °C. A further increase in temperature emphasized the influence of the pellet height on both gas yield and gas composition. Therefore, it can be argued that, in order to improve the gas yield and the quality of the syngas, the fast pyrogasification of large particles is advisable.