194 research outputs found
Factors Affecting Sustainable Consumer Behavior in the MENA Region: A Systematic Review
Sustainable consumer behavior (SCB) gained significant attention given the relevance it bears for a broad set of actors. Since most of the relevant literature is rooted in western countries, researchers and policymakers implicitly assume that behaviors in developing countries tend to replicate those in developed countries. This review, based on seventy-one articles published since 2000, questions such assumption by analyzing the empirical research on SCBs in the Middle East and North Africa (MENA), a distinctive region that has been so far overlooked by mainstream research. Results reveal that most MENA-based papers are rooted in traditional frameworks of the rationalistic stream and that environmental values represent a key driver of SCB, while habits and socio-demographics are relegated to a negligible role. This study provides an added value by synthesizing the fragmented evidence on the topic and discussing aspects emerging as peculiar of the MENA and differentiating the latter from other societies
Green synthetic fuels: Renewable routes for the conversion of non-fossil feedstocks into gaseous fuels and their end uses
Innovative renewable routes are potentially able to sustain the transition to a decarbonized energy economy. Green synthetic fuels, including hydrogen and natural gas, are considered viable alternatives to fossil fuels. Indeed, they play a fundamental role in those sectors that are di cult to electrify (e.g., road mobility or high-heat industrial processes), are capable of mitigating problems related to flexibility and instantaneous balance of the electric grid, are suitable for large-size and long-term storage and can be transported through the gas network. This article is an overview of the overall supply chain, including production, transport, storage and end uses. Available fuel conversion technologies use renewable energy for the catalytic conversion of non-fossil feedstocks into hydrogen and syngas. We will show how relevant technologies involve thermochemical, electrochemical and photochemical processes. The syngas quality can be improved by catalytic CO and CO2 methanation reactions for the generation of synthetic natural gas. Finally, the produced gaseous fuels could follow several pathways for transport and lead to different final uses. Therefore, storage alternatives and gas interchangeability requirements for the safe injection of green fuels in the natural gas network and fuel cells are outlined. Nevertheless, the effects of gas quality on combustion emissions and safety are considered
L’attuale sviluppo dell’EMAS e le prospettive per la nuova revisione
(In Inglese) In sight of the incoming revision process relating to the two most important voluntary instruments of the European Commission, the Ever study has been carried out on behalf of DG Environment, by a consortium of consultants led by Iefe Università Bocconi. The other partners in the consortium were Adelphi Consult, IOEW Office Heidelberg, SPRU Sussex University and Valør & Tinge A/S. The fundamental aim of the Ever study has been to provide recommendations for the revision of these voluntary schemes: Emas and the EU Eco-label. In particolar, the Ever study aimed, on one hand, at delivering a critical appraisal of both the Emas and the Eco-label scheme: the study analysed the relevance (take up and use), the effectiveness (impact on production and consumption patterns) and the efficiency (including cost efficiency) of the two schemes. Furthermore, it identified the drivers and barriers of both voluntary instruments, and investigate their utility (appropriateness as policy instruments) and their viability. On the other hand, the study aimed at providing recommendations by detailing options for improvement: these options shall regard the instruments themselves, linkages between them and linkages to other related initiatives and policies. The options and recommendations proposed for the schemes are based on the evidence collected in the different phases of the Ever study: the ‘desk research’, consisting of a thorough review of existing literature and previous studies and surveys on the schemes, and the ‘in-field’ research, carried out by way of direct interviews and case studies, provided the background relating to their strengths and weaknesses. This article aims at describing the results of the Ever study, with specific reference to Emas
Assessment of kinetic model for ceria oxidation for chemical-looping CO2 dissociation
Chemical looping technologies are identified as to have an excellent potential for CO2 capture and fuels synthesis. Oxygen carriers are the fundamental component of a chemical looping process, and the choice of stable and efficient carriers with fast redox kinetics is the key to the successful design of the process. Hence, understanding the reaction kinetics is of paramount importance for the selection of an appropriate oxygen carrier material. This work provides a method for kinetic model selection based on a statistical approach to identify the reaction mechanism. The study experimentally investigates the oxidation kinetics of CeO2-d by CO2 and applies a statistical method for the selection of the best-fitting kinetic model for the reaction. The kinetic study is performed in the temperature range of 700–1000¿°C with a CO2 concentration between 20 and 40¿vol% in the feed. The measured peak rates of CO production on ceria were influenced both by temperature and concentration of reactant. The total CO production was more influenced by the temperature than by CO2 concentration, with a maximum CO yield of 33.66¿ml/g at 1000¿°C and 40% CO2. The identification of the oxidation kinetic model is performed by fitting different reactions models to the measured reaction rates and statistically comparing them using the Residual sum of squares (RSS), Akaike information criterion (AICc) and the F-test for the selection of the best-fitting one. Models corresponding to the nucleation and grain growth reaction mechanism provided a good fit of the data, with the Sestak-Berggren (SB) model showing the best approximation of the measured rate of reaction with an evaluated activation energy of 79.1¿±¿6.5¿kJ/mol for the CO2 oxidation.Peer ReviewedPostprint (author's final draft
The energy center initiative at politecnico di torino: practical experiences on energy efficiency measures in the municipality of torino
Urban districts should evolve towards a more sustainable infrastructure and greener energy carriers. The utmost challenge is the smart integration and control, within the existing infrastructure, of new information and energy technologies (such as sensors, appliances, electric and thermal power and storage devices) that are able to provide multi-services based on multi-actors and multi and interchangeable energy carriers. In recent years, the Municipality of Torino represents an experimental scenario, in which practical experiences in the below-areas have taken place through a number of projects: 1. energy efficiency in building; 2. smart energy grids management and smart metering; 3. biowaste-to-energy: mixed urban/industrial waste management with enhanced energy recovery from biogas. This work provides an overview and update on the most interesting initiatives of smart energy management in the urban context of Torino, with an analysis and quantification of the advantages gained in terms of energy and environmental efficiency
Biofuels Policy in Europe Under the Directive 2003/30: An Analysis of Goals, Hindrances, Instruments and Effects
Up to 2008/2009, biofuels were considered one of the best alternatives to oil consumption in a captive market like transports, being one of the pillars of the 20-20-20 initiative in Europe. Improvement of security of supply through partial substitution of imported oil; reduction of GHGs emissions; improvement of income and employment in the agricultural and rural sectors were the main drivers of the promotion of biofuels in Europe, as well as in the United States and in Brazil. In the European Union biofuels policy was supported through Directive 2003/30. However its effects proved to be disappointing: the consumption of biofuels was expected by the Directive to account for 5.75% share of road fuels in 2010 in the European MSs, but it came early clear that such a target could not be met. Above all, consensus about biofuels decreased sharply when their ability to strongly decrease overall GHGs emissions was questioned, and when they were blamed of being the main responsible of the 2007-2008 food price increase. Finally, a new Directive was approved on April 23rd, 2009, including the request of various certifications to prove the sustainability of biofuels. The paper deals deeply with the biofuel experience in Europe, providing a general analysis of the 2003/30 Directive. It includes an evaluation of the difficulties met in satisfying the requested targets, an assessment of the MSs policies to support biofuels, and a discussion about the main features of the (failed) birth of a new industry
Small- bowel mucosal changes and antibody responses after low- and moderate-dose gluten challenge in celiac disease
<p>Abstract</p> <p>Background</p> <p>Due to the restrictive nature of a gluten-free diet, celiac patients are looking for alternative therapies. While drug-development programs include gluten challenges, knowledge regarding the duration of gluten challenge and gluten dosage is insufficient.</p> <p>We challenged adult celiac patients with gluten with a view to assessing the amount needed to cause some small-bowel mucosal deterioration.</p> <p>Methods</p> <p>Twenty-five celiac disease adults were challenged with low (1-3 g) or moderate (3-5g) doses of gluten daily for 12 weeks. Symptoms, small-bowel morphology, densities of CD3+ intraepithelial lymphocytes (IELs) and celiac serology were determined.</p> <p>Results</p> <p>Both moderate and low amounts of gluten induced small-bowel morphological damage in 67% of celiac patients. Moderate gluten doses also triggered mucosal inflammation and more gastrointestinal symptoms leading to premature withdrawals in seven cases. In 22% of those who developed significant small- intestinal damage, symptoms remained absent. Celiac antibodies seroconverted in 43% of the patients.</p> <p>Conclusions</p> <p>Low amounts of gluten can also cause significant mucosal deterioration in the majority of the patients. As there are always some celiac disease patients who will not respond within these conditions, sample sizes must be sufficiently large to attain to statistical power in analysis.</p
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