Low carbon housing: lessons from Elm Tree Mews

This report sets out the findings from a low carbon housing trial at Elm Tree Mews, York, and discusses the technical and policy issues that arise from it. The Government has set an ambitious target for all new housing to be zero carbon by 2016. With the application of good insulation, improved efficiencies and renewable energy, this is theoretically possible. However, there is growing concern that, in practice, even existing carbon standards are not being achieved and that this performance gap has the potential to undermine zero carbon housing policy. The report seeks to address these concerns through the detailed evaluation of a low carbon development at Elm Tree Mews. The report: * evaluates the energy/carbon performance of the dwellings prior to occupation and in use; * analyses the procurement, design and construction processes that give rise to the performance achieved; * explores the resident experience; * draws out lessons for the development of zero carbon housing and the implications for government policy; and * proposes a programme for change, designed to close the performance gap

Electrical and Structural Analysis of CNT-Metal Contacts in Via Interconnects

Vertically aligned carbon nanotubes grown by plasmaenhanced chemical vapor deposition offer a potentially suitable material for via interconnects in next-generation integrated circuits. Key performance-limiting factors include high contact resistance and low carbon nanotube packing density, which fall short of meeting the requirements delineated in the ITRS roadmap for interconnects. For individual carbon nanotube s, contact resistance is a major performance hurdle since it is the dominant component of carbon nanotube interconnect resistance, even in the case of vertically aligned carbon nanotube arrays. In this study, we correlate the carbon nanotube-metal interface nanostructure to their electrical properties in order to elucidate growth parameters that can lead to high density and low contact resistance and resistivity

Lightweight piston

A lightweight piston composed of carbon-carbon composites is presented. The use of carbon-carbon composites over conventional materials, such as aluminum, reduces piston weight and improves thermal efficiency of the internal combustion reciprocation engine. Due to the negligible coefficient of thermal expansion and unique strength at elevated temperatures of carbon-carbon, the piston-to-cylinder wall clearance is so small as to eliminate the necessity for piston rings. Use of the carbon-carbon composite has the effect of reducing the weight of other reciprocating engine components allowing the piston to run at higher speeds and improving specific engine performance

Preparation of controlled porosity carbon aerogels for energy storage in rechargeable lithium oxygen batteries

Porous carbon aerogels are prepared by polycondensation of resorcinol and formaldehyde catalyzed by sodium carbonate followed by carbonization of the resultant aerogels in an inert atmosphere. Pore structure of carbon aerogels is adjusted by changing the molar ratio of resorcinol to catalyst during gel preparation and also pyrolysis under Ar and activation under CO2 atmosphere at different temperatures. The prepared carbons are used as active materials in fabrication of composite carbon electrodes. The electrochemical performance of the electrodes has been tested in a Li/O2 cell. Through the galvanostatic charge/discharge measurements, it is found that the cell performance (i.e. discharge capacity and discharge voltage) depends on the morphology of carbon and a combined effect of pore volume, pore size and surface area of carbon affects the storage capacity. A Li/O2 cell using the carbon with the largest pore volume (2.195 cm3/g) and a wide pore size (14.23 nm) showed a specific capacity of 1290 mA h g−1

Tourism carbon Kuznets-curve hypothesis: a systematic literature review and a paradigm shift to a corporation-performance perspective

Since the introduction of the carbon Kuznets-curve hypothesis in the mid-1990s, the inverted U–shaped relationship between economic development and carbon emissions has remained a subject of debate in the social sciences. We engage tourism research in this debate, in a fourfold manner. First, we offer a systematic literature review concerning the role of tourism in the carbon Kuznets-curve hypothesis using a protocol-based reporting process. Second, we present the level of consensus with the carbon Kuznets-curve hypothesis and the conceptual gaps in the identified literature (n = 22). Third, we introduce an emerging concept, offering a novel tourism corporate/performance orientation to the carbon Kuznets-curve hypothesis. Fourth, we provide evidence of empirical validity using different econometric techniques from an international tourism corporation (n = 86) data set (2005–2018). The inverted U–shaped relationship between measures of economic and carbon performance among tourism corporations is a robust result under many different specifications

MaB-flocs for a more sustainable wastewater treatment

Conventional wastewater treatment with activated sludge has a large carbon footprint, high aeration rates are combined with CO2 emission from bacteria. By using micro-algal bacterial flocs (MaB-flocs), CO2 could be captured within the biomass and oxygen could be produced in situ. In order to maximize this photosynthetic aeration and CO2 mitigation, we investigated whether inorganic carbon could alter the algae/bacteria ratio while keeping a good removal performance and settleability of the MaB-flocs. Therefore, three illuminated sequencing batch reactors with MaB-flocs were fed with synthetic wastewater enriched with 84.2, 42.1 and 0 mg L-1 C-KHCO3 supplemented with 0, 42.1, 84.2 mg L-1 C-sucrose, respectively, representing the inorganic carbon source compared to an organic carbon source. Bicarbonate significantly increased the chlorophyll a concentration of the MaB-flocs, but only poor settling flocs could be obtained causing a high turbidity of the effluent. Moreover, significant lower nitrogen removal efficiencies were measured feeding bicarbonate compared to sucrose and the pH increased (9.5). Sucrose benefited a good reactor performance and showed a good settleability of MaB-flocs. Despite the lower chlorophyll a concentration of the biomass and the lower in situ oxygen concentration, average soluble COD removal efficiencies of 95 % were achieved with sucrose. Furthermore sucrose was successful in containing the optimal pH at 7. This study shows the importance of the carbon source for a good reactor performance. As a consequence, the inorganic/organic carbon ratio of the wastewater should be taken into account when algal bacterial reactors are used for wastewater treatment

Micro milling performance assessment of diamond-like carbon coatings on a micro-end mill

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2013 Institution of Mechanical Engineers.In micro milling, unpredictable tool life and premature tool failures are the major constraints for its industrial applications, and prolongation of the tool life so as to enhance the tooling performance presents great challenges. Appropriate coating techniques potentially offer a feasible and promising solution. In this study, diamond-like carbon films are deposited on a Ø500 µm diameter tungsten carbide (WC) micro-end mill by the plasma-enhanced chemical vapour deposition process. Coating characterisation has been undertaken and the diamond-like carbon coatings are found in good coverage on the tool except for a slight delaminating on the edge corners. Besides, the surface of the amorphous coatings is much smoother than that of WC. In addition, comprehensive cutting performance of the diamond-like carbon coated tool in dry slot milling of Al 6061-T6 has been compared with those of uncoated tools in both dry and wet conditions. It is observed that the use of diamond-like carbon coatings can reduce the cutting forces, lessen the tool wear, improves the surface roughness and minimise the micro-burr formation as compared to the corresponding performance of an uncoated tool in dry cutting. However, the performance improvement is still unreachable to those resulting from the cutting fluid influence.UK Technology Strategy Board and Kistler UK Ltd