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Fuel distribution measurements in a model low NOx double annular combustor using laser induced fluorescence
Planar laser induced fluorescence (PLIF) was employed in a three sector, low NOx double annular combustor in order to characterise the combusting fuel spray. Naphthalene was employed as a fluorescent agent in odourless kerosene in order to determine the behavior of the light fractions in the fuel vapour, and the light to medium fractions in the fuel spray, while 2,5 di-phenyl oxizol (ppo) was employed to determine the behavior of the heavy fractions in the fuel spray. Counter-swirl air blast atomizing fuel injectors employing a nominal fuel spray included cone angle of 90 deg were employed to inject the kerosene fuel into the double annular combustor. Radial and axial measurements were performed on the combusting spray. Spatial variations in fuel spray placement were observed, together with radial anisotropy
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The optical characterisation of spray and soot formation in a diesel engine
Laser sheet drop-sizing (LSD) measurements of a Diesel spray and simultaneous laser induced incandescence/Mie scattering measurements of soot have been performed in an optically accessible, common rail, 1.9 litre, turbo-charged, direct injection Diesel engine. The diesel fuel injectors employed in this study were prototype five hole injectors, supplied by R. Bosch. An oxygenated surrogate Diesel fuel with an estimated cetane number of 54 was employed in order to reduce the amount of soot formed during combustion. The prototype five-hole injector employed produced spray jets that were distinguishable in terms of the liquid volume fraction, drop-size distribution and spray penetration distance produced. The soot volume fraction formed during combustion was found to be correlated with drop-size distribution, and local soot particle size distribution was observed to be inversely correlated with local soot volume fraction
Gender differences in the kinetics and kinematics of distance running: implications for footwear design
Interest in distance running amongst females has expanded rapidly. Although there are numerous health benefits associated with running, the occurrence of injury is well documented. Given the relative susceptibility of females to overuse running injuries, a key issue within the discipline of footwear biomechanics that has yet to be appropriately addressed is the specific demands of athletic footwear for females. The aim of this study was therefore to provide both a kinetic and 3-D kinematic comparison of male and female runners in order to determine the relative susceptibility of females to the proposed mechanisms of overuse injuries and whether based on this information, females require more specific footwear designs to meet their needs. Twelve male participants and twelve female participants completed five successful trials running at 4.0ms-1+5%. 3-D angular joint kinematics from the hip, knee and ankle were collected using an eight camera motion analysis system. In addition simultaneous tibial acceleration and ground reaction forces were obtained. Differences in impact parameters and joint kinematics were subsequently compared using independent samples t-tests. Females were found to be associated with significantly greater knee abduction, knee internal rotation and ankle eversion, whilst males were associated with significantly greater hip flexion. Based on these findings it is recommended that females select running footwear with design characteristics aimed towards the reduction of coronal plane ankle eversion in order to reduce the incidence of injury
An examination of business occupier relocation decision making : distinguishing small and large firm behaviour
This paper explores how business occupiers decide whether and where to relocate. It captures the experience and behaviour of a range of sizes and types of business occupier and subjects their decision-making processes to detailed scrutiny. A linear three-stage decision model is used to sequence and structure interviews with individuals who have intimate involvement with the relocation of 28 firms and organizations in Tyne and Wear, in the north-east of England. The 'constant comparative' method is used to analyse the interview data, from which emerges 18 key concepts, comprising 51 characteristic components. Using an axial approach, these are organized into 10 cross-cutting themes that represent the main areas of consideration or influence on the thinking of the people involved in determining whether a firm or organization should relocate and, if so, where to. The resulting analysis finds that organizations adopt varying degrees of sophistication when making relocation decisions; small firms are more inclined to make decisions based on constrained information; larger organizations adopt a more complex approach. Regardless of firm size, key individuals exert considerable influence over the decision-making process and its outcome
Iron-catalysed, hydride-mediated reductive cross-coupling of vinyl halides and Grignard reagents
Shared visiting in Equator city
In this paper we describe an infrastructure and prototype system for sharing of visiting experiences across multiple media. The prototype supports synchronous co-visiting by physical and digital visitors, with digital access via either the World Wide Web or 3-dimensional graphics
Caring for the patient, caring for the record: an ethnographic study of 'back office' work in upholding quality of care in general practice
© 2015 Swinglehurst and Greenhalgh; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Additional file 1: Box 1. Field notes on summarising (Clover Surgery). Box 2. Extract of document prepared for GPs by summarisers at Clover
Surgery. Box 3. Fieldnotes on coding incoming post, Clover (original notes edited for brevity).This work was funded by a research grant from the UK Medical Research Council (Healthcare Electronic Records in Organisations 07/133) and a
National Institute of Health Research doctoral fellowship award for DS (RDA/03/07/076). The funders were not involved in the selection or analysis of data nor did they make any contribution to the content of the final
manuscript
The impact of genetic counselling on risk perception in women with a family history of breast cancer.
Women with a family history of breast cancer generally self-refer because they have a feeling that their risk is high. However, they have, in general, only a hazy notion of the population risk of breast cancer and their own risk in relation to this. It is probable that they are helped by genetic counselling and, if at substantial risk, by annual mammography. However, the psychological impact of assigning true risk and the value of mammography need to be evaluated. We have assessed risk perception by questionnaire in 517 new referrals to a family history clinic and 200 women returning to the clinic at least 1 year after counselling. Correct assignment of population lifetime risk of breast cancer was 16% in the uninformed precounsel group and 33% in the post-counsel group, likewise personal risk was correct in 11% and 41% respectively. Post-counsel women were significantly more likely to retain information if they were sent a post-clinic letter or if they assessed their personal risk as too high initially
Piezoresistive structural composites reinforced by carbon nanotube-grafted quartz fibres
Nano-engineered fibre/matrix interfaces can improve state-of-the-art fibre-reinforced composites. Grafting carbon nanotubes (CNTs) to high temperature quartz glass fibres produces “hairy” or “fuzzy” fibres, which combine reinforcements at micrometre and nanometre length scales. Fuzzy quartz fibres were produced continuously, reel-to-reel, on whole tows, in an open chemical vapour deposition reactor. The resulting uniform coverage of 200 nm long CNTs increased the interfacial shear strength with epoxy (90.3 ± 2.1 MPa) by 12% compared to the commercially-sized counterpart, as measured by single fibre pull-out tests. The improved interfacial properties were confirmed at the macroscale using unidirectional hierarchical bundle composites, which exhibited a delayed onset of fibre/matrix debonding. Although the quartz fibres are electrically insulating, the grafted CNT create a conductive path, predominantly parallel to the fibres. To explore the applicability for structural health monitoring, the resistivity was recorded in situ during mechanical testing, and correlated with simultaneous acoustic emission data. The baseline resistivity parallel to the fibres (ρ0 = 3.9 ± 0.4 × 10−1 Ω m) displayed a linear piezoresistive response (K = 3.64) until failure at ca. 2.1% strain, also referred to as "gauge factor”, a two-fold improvement over traditional resistance strain gauges (e.g. constantan). Hierarchical, fuzzy quartz fibres, therefore, simultaneously enhance both structural and sensing performance, offering multifunctional opportunities in large composite parts
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