Search results for "NEWA"
showing 10 items of 2491 documents
Fuzzy modeling of solar irradiance on inclined surfaces
2003
A model of solar irradiance on arbitrarily oriented inclined surfaces is proposed, based on fuzzy logic procedures. The behavior of the proposed model is similar to that of other models of increased performance such as the models of Perez or Gueymard, though it requires only a very limited number of classes and adjustable parameters. The use of fuzzy clustering optimizes the number and definition of the sky categories. The model considers overlapping clusters and allows an improved description of the sky situations close to the transition zone between contiguous categories.
Opening the black box of accounting for Greenhouse Gas Emissions: The different views of institutional bodies and firms
2018
Abstract This paper highlights the current accounting approaches to greenhouse gas (GHG) emissions. In particular, it explores and critically discusses the treatment of emission rights (ER) under carbon trading schemes from two distinct angles. On the one hand, it reviews the domestic solutions adopted by accounting bodies and, on the other, it examines current practices followed by firms in the European Energy Exchange (EEX). Regarding the former group, there are substantial differences, which would suggest some potential difficulties in finding a common solution for the future. Not surprisingly, there is still a diversity of approaches with regard to how firms report ER. Although the most…
Mapping Seasonal Variability of Buildings Electricity Demand profiles in Mediterranean Small Islands
2023
In communities with a high tourist influx and warm climate, such as Mediterranean small islands, the energy demands for space cooling and domestic hot water are expected to significantly increase during summer. Considering the current energy context, for succeeding energy transition and reducing the dependency on not endogenous fossil fuels, it is paramount to increase the deployment of renewable sources of energy, especially wind and solar which, however, are aleatory and unpredictable. Hence, to reduce the high costs for energy supply in these contexts, the analysis of the variation of energy consumption is fundamental. Moreover, mapping the spatial distribution of energy profiles can be …
A GIS-based optimization model finalized to the localization of new power-to-gas plants: The case study of Sicily (Italy)
2022
In 2020 the European Commission approved the GND (Green New Deal), a strategic plan aimed at the decarbonization of the EU by 2050. In this scenario, the diffusion of alternative renewable energy sources (RESs) play a key role, particularly electric energy production from wind and photovoltaic power plants. Regardless, the nonprogrammable nature of these power sources led recent studies to focus the interest on the power-to-gas solution (PtG), consisting of the electrolytic transformation of excesses of unused electric energy into hydrogen. The complexity of this technology requires the development of strategic optimization models aimed at finding the best locations for new PtG plants in sp…
Metals in aqueous solutions and real effluents: biosorption behavior of a hemp-based felt
2018
In this study, a hemp-based material in the form of a felt is used to adsorb metals in individual aqueous solutions and in polycontaminated effluents using the batch method. The factors affecting the biosorption process were initial metal concentration, biosorbent dosage, contact time and pH. In controlled conditions, results showed that: (i) the felt exhibited high adsorption capacities towards metals in the following order: Pb g (ii) no significant differences were observed for the three salts used (sulfate, chloride and nitrate); (iii) the process was rapid: 10 min were sufficient to attain equilibrium ; iv) the biosorption efficiency increased considerably with the increase of the bioso…
Modelling wet-air oxidation of phenol in a trickle-bed reactor using active carbon as a catalyst
2014
BACKGROUND Catalytic wet air oxidation (CWAO) of phenol in a trickle-bed reactor has been investigated (operating parameters: P=1.85 MPa, T=393, 413, 433 K, L=0.17–1.77 kg m−2 s−1 and G=0.2–0.62 kg m−2 s−1). Activated carbon was used as a catalyst. The experimental results have been simulated by Eulerian multifluid model (CFD) and for comparison by the plug flow model. RESULTS The experiments proved that active carbon can be applied as a catalyst in the phenol oxidation processes revealing a catalytic activity comparable with that of commonly used metal oxides. The highest conversion of phenol obtained in long-lasting experimental runs carried out at stable catalytic activity (PO2 = 0.31 MP…
Green and Direct Synthesis of Benzaldehyde and Benzyl Benzoate in One Pot
2018
High yields of valued benzaldehyde and benzyl benzoate are obtained in one pot starting from benzyl alcohol using oxygen as only oxidant under mild conditions (2 bar O2, 100 °C) along with an ultralow amount (0.02 mol %) of Au nanoparticles heterogenized over a spherical ORMOSIL mesoporous support. The process is remarkably selective and the catalyst is stable.
FeOOH and Mn8O10Cl3modified zeolites for As(V) removal in aqueous medium
2017
BACKGROUND Arsenic in drinking water poses serious potential health risks in more than 30 countries with total affected population of around 100 million people. The present study is devoted to the development of innovative sorbents based on zeolite materials for As(V) sorption by modifying raw materials with iron oxyhydroxide and manganese oxychloride. Natural clinoptilolite and synthetic zeolite A were modified in order to obtain improved sorption of As(V). Sorption properties of newly developed sorbents were studied. Zeolites containing natural clinoptilolite are chosen due to relatively low cost and their broad use in industrial production as well as characteristic large surface area. RE…
Self-Sustaining Supramolecular Ionic Liquid Gels for Dye Adsorption
2018
Water contamination is one of the main problems of modern society, and scientific research is continuously involved in identifying solutions able to preserve this valuable source. In this context, we characterized novel ionogels formed by organic salts with different anions. In particular, they show self-strengthening behavior, a quite unusual property for supramolecular gels, and they also exhibit a good load-bearing capacity. These ionogels are able to remove cationic dyes from wastewater. Thanks to their properties, they can be used in different apparatuses like dialysis membranes and as loading in adsorption columns. In the latter case over 95% removal is achieved in less than 10 min. I…
Isotopic composition of dissolved sulphate and hydrogen sulphide from some thermal springs of Sicily
1982
Samples of some thermal springs from Sicily have been analysed for the isotopic composition of sulphur-bearing species. The values of δ34S(SO42− (range: +7.3, +31.7‰), δ34S(H2S) (range: −12.2, +27.8), δ34S(S°) (range: +1.9, +24.5) and δ18O(SO42−) (range: −2.5, +23.9) obtained show such a remarkable variability in data as to hypothesize different genetic processes concerning these species. Furthermore, from the available experimental data, the relationship between the isotopic composition of the sulphur in the dissolved sulphate and in the associated hydrogen sulphide (ΔSO42− - H2S = 25 – 30‰) seems to indicate the bacterial reduction of sulphate ion as one of the processes most significantl…