The mechanical properties of inconel 718 sheet alloy at 800 deg, 1000 deg, and 1200 deg f

Mechanical properties of Inconel sheet superalloy at very high temperatures for supersonic transpor

Do technical improvements lead to real efficiency gains? Disaggregating changes in transport energy intensity

Fuel economy standards are a key measure to increase the rate of efficiency improvements in passenger cars. The fuel consumption of vehicles can be improved in three ways: incremental technical efficiency improvements within powertrain technologies, market shifts to more efficient types of powertrains and by limiting increases in the size and performance of vehicles. This study quantifies the effect of each of these three drivers on the fuel consumption of British vehicles between 2001 and 2018 using driver-reported data on real-world fuel consumption. Analysis shows the introduction of EU fuel economy standards in 2008/09 had little effect on the rate of real technical efficiency improvements in British vehicles. Instead of adopting technical improvements at a higher rate or limiting the size and power of vehicles, these results suggest vehicle manufacturers met emissions standards by increasing the divergence between laboratory tests and real-world fuel consumption. This study adds to the growing literature calling for official test procedures to be representative of real-world driving

The quality rebound effect in transportation

© 2019 European Council for an Energy Efficient Economy. All rights reserved. Energy is needed in society to provide energy services. Reducing the energy to deliver these services is at the core of energy efficiency. Energy services have both a quantitative and qualitative value. In the case of transportation, the quantity of service can be expressed simply in passenger kilometres, whereas quality aspects are affected by several vehicle attributes such as size and performance as well as travel times and comfort. Improving energy efficiency can stimulate consumers to travel more and thus consume a greater quantity of transportation. This phenomenon is known as the 'rebound' effect and has been well studied. Less studied are rebound effects in quality of service; how reductions in travel costs, due to fuel price changes and technical efficiency improvements, can stimulate people to increase the quality of transport, for example by purchasing a larger vehicle. Consumers continue to buy larger and more powerful vehicles in many countries. These purchasing trends mean that technical improvements in vehicle fuel consumption are undermined by shifts to larger vehicle segments. New hybrid and electric powertrains entering the market promise large improvements in fuel consumption. However, if these efficiency improvements stimulate shifts to even larger vehicles through quality rebound effects, the full potential energy savings may not materialise. Understanding and quantifying these quality rebound effects is therefore of paramount importance for energy modellers and policy makers. This paper uses a unique dataset of vehicle sales in the UK between 2001 and 2017, to investigate the effects of fuel price, income and technical improvements on stimulating a shift to larger and more powerful vehicles. Econometric regression techniques are used to show increasing income and the growing share of diesel and hybrid powertrains partially explain the shift to large vehicles. This suggests vehicle taxes in larger segments have not been sufficiently high and need to be rectified

Do vehicle efficiency improvements lead to energy savings? The rebound effect in Great Britain

Fuel efficiency improvements in vehicles reduce the cost of travel, which could stimulate drivers to travel further limiting energy savings. Estimates of this effect, known as the rebound effect, have varied widely, partly due to data constraints and a reliance upon highly aggregated government statistics. This paper instead uses a dataset of over 275 million vehicle roadworthiness tests. The high level of detail in our dataset can reveal, for the first time, how the response to changes in travel costs may differ across types of vehicles and socio-economic areas in Great Britain. We find that the rebound effect in Great Britain is just 4.6%, meaning efficiency improvements are unlikely to stimulate increased mileage in the short-run. We find that larger, less fuel efficient vehicles are more responsive to fuel price changes than smaller vehicles and that drivers in urban areas are more responsive to fuel price changes than drivers in rural areas. Our findings shed light on the effects that policies such as fuel taxation and fuel economy standards may have on vehicle mileage. This has implications for both CO2 emissions savings and social equity

Modelling transport emissions in an uncertain future: What actions make a difference?

© 2020 Elsevier Ltd A range of technology and policy actions can be put in place to reduce carbon emissions from passenger cars, this paper aims to prioritise between them, based on their likely impact and uncertainty. Formal sensitivity analysis techniques are used for the first time to determine the relative importance of factors affecting future emissions from passenger vehicles in Great Britain. The two most important actions to limit future life-cycle CO2 emissions involve shifting to electric vehicles and limiting trends towards larger and more powerful vehicles. According to our analysis over 80% of the uncertainty in future cumulative CO2 emissions can be attributed to uncertainty in electric vehicle uptake and vehicle size and power. These variables are a priority for transport policy makers. The analysis also highlights variables of comparatively low importance; these include the share of hybrid electric vehicles, the Rebound Effect and the utilisation factor of PHEVs

An Assessment of the potential impact of the Gothenburg Protocol on surface water chemistry using the dynamic MAGIC model at acid sensitive sites in the UK

International audienceThe MAGIC model has been systematically calibrated to 12 sites in the UK, which form part of the UK Acid Waters Monitoring Network, using best available data. The model successfully simulates observed changes in major ions and acid neutralising capacity over the period 1988 to 2000. Predictions for the future are made assuming no further emission reductions from present day (constant deposition at current level) compared to reduced sulphur and nitrogen emission agreed under the Gothenburg Protocol (reduced sulphur dioxide emission by c.80%, nitrogen oxides by c.45% and ammonia by 20% by 2010). In addition, uncertainty in our understanding of future nitrogen dynamics is assessed using "best" and "worst" cases of nitrogen leaching in the model. The results clearly indicate the need to achieve further emission reductions in sulphur and nitrogen beyond present day levels to prevent continued surface water acidification. The predictions further indicate that if the emission reductions agreed under the Gothenburg Protocol are achieved by 2010 this will promote a recovery in acid neutralising capacity by 2020 at all sites. Differences between "best" and "worst" case nitrate leaching are relatively small, emphasising the need to achieve the sulphur reductions in the shorter term. In the longer term, beyond 2020, increased nitrogen leaching under the "worst case" leading to further acidification is likely indicating a need for further reduction of nitrogen emissions. Keywords: acidification, recovery, model, Gothenburg Protocol, nitroge

Trace-metaldynamics in response of increase CO₂ and iron availability in a coastal mesocosm experiment

A mesocosm experiment was performed in the Raunefjord (Norway) to study changes in dissolved Cu (dCu) and Fe (dFe), and in the elemental composition of particles during an Emiliania huxleyi dominated bloom. The CO2 treatments consisted of present (LC; 390 ppmV) and predicted levels (HC; 900 ppmV) and iron conditions were created with the addition of the siderophore desferoxamine B (DFB). Our results showed the DFB addition enhanced the solubility of Fe in this fjord environment. Initially, dFe was comparable among treatments but after the addition, the HC and/or +DFB treatments presented higher levels and finally, the only ones maintaining high dFe were the +DFB treatments. Unlike dCu presented indistinguishable levels in all mesocosms over time. Particulate metals were normalised to P and Al to evaluate the relative influence of biotic and abiotic sources. The Fe:P ratios decreased with time and compared to published phytoplankton ratios suggest Fe storage. On the other hand, Fe:Al ratios were relatively closer to the crustal ratios suggesting that the abiotic source was more important for this metal. Trends for other metals will be discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech