Search results for " fuel"
showing 10 items of 426 documents
A six legs buck-boost interleaved converter for KERS application
2020
This paper addresses the design of a bi-directional DC/DC power converter to interface a supercapacitor bank and a motor-generator unit. The design is based on an interleaved six legs topology in which the current is shared among six inductors to minimize their weight and cost, allowing, besides, a low switching frequency to lessen switching losses. The converter is conceived to be employed in an electric Kinetic Energy Recovery System for Internal Combustion Engine Vehicles. The system makes use of a supercapacitor as a storage system, and a motorgenerator unit connected to the drive shaft for vehicle acceleration and braking. The system uses available commercial devices, thus obtaining a …
The Anti Nuclear Litany
2012
Can nuclear energy become a viable alternative to fossil fuels? Almost all of French electricity is generated in nuclear plants, as is half of the electricity in Ukraine, Sweden and Belgium, a third in Finland and South Korea and a fifth in many other countries, among them Spain, Germany, the UK and the USA.
Loss of life expectancy from air pollution compared to other risk factors: a worldwide perspective
2020
Abstract Aims Long-term exposure of humans to air pollution enhances the risk of cardiovascular and respiratory diseases. A novel Global Exposure Mortality Model (GEMM) has been derived from many cohort studies, providing much-improved coverage of the exposure to fine particulate matter (PM2.5). We applied the GEMM to assess excess mortality attributable to ambient air pollution on a global scale and compare to other risk factors. Methods and results We used a data-informed atmospheric model to calculate worldwide exposure to PM2.5 and ozone pollution, which was combined with the GEMM to estimate disease-specific excess mortality and loss of life expectancy (LLE) in 2015. Using this model, …
The association of cooking fuels with depression and anxiety symptoms among adults aged ≥65 years from low- and middle-income countries
2022
Background: We aimed to investigate associations of unclean cooking fuels with depression and anxiety symptoms in a large sample of adults aged ≥65 years from six low- and middle-income countries (LMICs). Methods: Cross-sectional, community-based, nationally representative data from the WHO Study on global AGEing and adult health (SAGE) were analyzed. Unclean cooking fuel referred to kerosene/paraffin, coal/charcoal, wood, agriculture/crop, animal dung, and shrubs/grass. Depression referred to DSM-IV depression based on past 12-month symptoms or receiving depression treatment in the last 12 months. Anxiety symptoms referred to severe/extreme problems with worry or anxiety in the past 30 day…
The insectivorous batPipistrellus nathusiiuses a mixed-fuel strategy to power autumn migration
2012
In contrast to birds, bats are possibly limited in their capacity to use body fat as an energy source for long migrations. Here, we studied the fuel choice of migratoryPipistrellus nathusii(approximate weight: 8 g) by analysing the stable carbon isotope ratio (δ13CV-PDB) of breath and potential energy sources. Breathδ13CV-PDBwas intermediate betweenδ13CV-PDBof insect prey and adipocyte triacylglycerols, suggesting a mixed-fuel use ofP. nathusiiduring autumn migration. To clarify the origin of oxidized fatty acids, we performed feeding experiments with captiveP. nathusii. After an insect diet, bat breath was enriched in13C relative to the bulk and fat portion of insects, but not deviating fr…
Metallic interconnects for SOFC: Characterisation of corrosion resistance and conductivity evaluation at operating temperature of differently coated …
2007
Abstract One of challenges in improving the performance and cost-effectiveness of solid oxide fuel cells (SOFCs) is the development of suitable interconnect materials. Recent researches have enabled to decrease the operating temperature of the SOFC from 1000 to 800 °C. Chromia forming alloys are then among the best candidates for interconnects. However, low electronic conductivity and volatility of chromium oxide scale need to be solved to improve interconnect performances. In the field of high temperature oxidation of metals, it is well known that the addition of reactive element into alloys or as thin film coatings, improves their oxidation resistance at high temperature. The elements of …
Light-Induced Formation of Pb3+Paramagnetic Species in Lead Halide Perovskites
2018
Hybrid halide perovskites are soft materials processed at room temperature, revolutionary players in the photovoltaic field. Nowadays, investigation of the nature and role of defects is seen as one of the key challenges toward full comprehension of their behavior and achievement of high device stability under working conditions. We reveal the reversible generation, under illumination, of paramagnetic Pb3+ defects in CH3NH3PbI3, synthesized in ambient conditions, induced by the presence of Pb-O defects in the perovskite structure that may trap photogenerated holes, possibly mediated by the concomitant oxidation and migration of ions. According to the mechanism that we hypothesize, one charge…
Metallic interconnects for solid oxide fuel cell: Effect of water vapour on oxidation resistance of differently coated alloys
2009
International audience; The need of interconnect to separate fuel and oxidant gasses and connect individual cells into electrical series in a SOFC stack appears as one of the most important point in fuel cell technology. Due to their high electrical and thermal conductivities, thermal expansion compatibility with the other cell components and lowcost, ferritic stainless steels (FSS) are nowconsidered to be among the most promising candidate materials as interconnects in SOFC stacks. Despite the formation at 800 ◦C of a protective chromia Cr2O3 scale, it can transform in volatile chromium species, leading to the lost of its protectiveness and then the degradation of the fuel cell. A previous…
NOX reduction and efficiency improvements by means of the Double Fuel HCCI combustion of natural gas–gasoline mixtures
2016
Abstract Homogeneous Charge Compression Ignition (HCCI) and Double Fuel (DF) combustion represent two innovative processes sharing a strong potential for pollutant emissions and fuel consumption reduction. HCCI regards the auto-ignition of a homogeneous premixed charge of air and fuel, featuring very low NOX emissions and good efficiency. Double Fuel (DF) instead indicates the simultaneous combustion of gasoline and natural gas (or gasoline and LPG), premixed with air by the port injection of both fuels within same engine cycle. Since fuel mixtures enhances the HCCI performances widening the range of possible operating conditions, the authors tested the HCCI combustion process using natural…
PEM electrolyzer characterization with carbon-based hardware and material sets
2021
Abstract The research and development of proton exchange membrane water electrolysis (PEMWE) is an upcoming and growing area due to a rising interest in hydrogen as an energy carrier. Operating conditions are harsher than in a fuel cell system, particularly because the potentials required for the oxygen evolution reaction are significantly higher. In commercial water electrolysis systems, this is compensated by typically using titanium material sets that are often protected against oxidation through coating processes. Such material choices make small scale research hardware and porous transport layers expensive and difficult to source. In this work, we show that the stability of traditional…