966 resultados para room set up


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The hydroformylation of 1-octene under continuous flow conditions is described. The system involves dissolving the catalyst, made in situ from [ Rh(acac)(CO)(2)] (acacH = 2,4- pentanedione) and [RMIM][TPPMS] ( RMIM = 1-propyl (Pr), 1-pentyl (Pn) or 1-octyl (O)-3-methyl imidazolium, TPPMS = Ph2P(3-C6H4SO3)), in a mixture of nonanal and 1-octene and passing the substrate, 1-octene, together with CO and H-2 through the system dissolved in supercritical CO2 (scCO(2)). [PrMIM][TPPMS] is poorly soluble in the medium so heavy rhodium leaching (as complexes not containing phosphine) occurs in the early part of the reaction. [PnMIM][ PPMS] affords good rates at relatively low catalyst loadings and relatively low overall pressure (125 bar) with rhodium losses <1 ppm, but the catalyst precipitates at higher catalyst loadings, leading to lower reaction rates. [OMIM][ TPPMS] is the most soluble ligand and promotes high reaction rates, although preliminary experiments suggested that rhodium leaching was high at 5-10 ppm. Optimisation aimed at balancing flows so that the level within the reactor remained constant involved a reactor set up based around a reactor fitted with a sight glass and sparging stirrer with the CO2 being fed by a cooled head HPLC pump, 1-octene by a standard HPLC pump and CO/H-2 through a mass flow controller. The pressure was controlled by a back pressure regulator. Using this set up, [OMIM][ TPPMS] as the ligand and a total pressure of 140 bar, it was possible to control the level within the reactor and obtain a turnover frequency of ca. 180 h(-1). Rhodium losses in the optimised system were 100 ppb. Transport studies showed that 1-octene is preferentially transported over the aldehydes at all pressures, although the difference in mol fraction in the mobile phase was less at lower pressures. Nonanal in the mobile phase suppresses the extraction of 1-octene to some extent, so it is better to operate at high conversion and low pressure to optimise the extraction of the products relative to the substrate. CO and H2 in the mobile phase also suppress the extraction effciency by as much as 80%.

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Margins are used in radiotherapy to assist in the calculation of planning target volumes. These margins can be determined by analysing the geometric uncertainties inherent to the radiotherapy planning and delivery process. An important part of this process is the study of electronic portal images collected throughout the course of treatment. Set-up uncertainties were determined for prostate radiotherapy treatments at our previous site and the new purpose-built centre, with margins determined using a number of different methods. In addition, the potential effect of reducing the action level from 5 mm to 3 mm for changing a patient set-up, based on off-line bony anatomy-based portal image analysis, was studied. Margins generated using different methodologies were comparable. It was found that set-up errors were reduced following relocation to the new centre. Although a significant increase in the number of corrections to a patient's set-up was predicted if the action level was reduced from 5 mm to 3 mm, minimal reduction in patient set-up uncertainties would be seen as a consequence. Prescriptive geometric uncertainty analysis not only supports calculation and justification of the margins used clinically to generate planning target volumes, but may also best be used to monitor trends in clinical practice or audit changes introduced by new equipment, technology or practice. Simulations on existing data showed that a 3 mm rather than a 5 mm action level during off-line, bony anatomy-based portal imaging would have had a minimal benefit for the patients studied in this work.

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A dynamic mathematical model for simulating the coupled heat and moisture migration through multilayer porous building materials was proposed. Vapor content and temperature were chosen as the principal driving potentials. The discretization of the governing equations was done by the finite difference approach. A new experimental set-up was also developed in this study. The evolution of transient temperature and moisture distributions inside specimens were measured. The method for determining the temperature gradient coefficient was also presented. The moisture diffusion coefficient, temperature gradient coefficient, sorption–desorption isotherms were experimentally evaluated for some building materials (sandstone and lime-cement mortar). The model was validated by comparing with the experimental data with good agreement. Another advantage of the method lies in the fact that the required transport properties for predicting the non-isothermal moisture flow only contain the vapor diffusion coefficient and temperature gradient coefficient. They are relatively simple, and can be easily determined.

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This paper assesses the development and functioning of regional minimum wage regulation in Northern Ireland in the interwar period under a federal form of devolution. Unlike current devolution arrangements in Scotland and Wales, this gave the Stormont Parliament powers over employment and minimum wage regulation. Northern Ireland Trade Boards were set up by the Ulster Unionist Government under the Trade Boards (Northern Ireland) Act 1923 and functioned along the same lines as those in Great Britain. Uniquely in the UK in this period, employer opposition resulted in the main Trade Board in the Irish Linen Industry being replaced by voluntary collective bargaining machinery. About one-quarter of employees were covered by minimum wage regulation, including two-thirds of females in Belfast, keeping a protective floor under low pay.

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The acquisition of radiotherapy planning scans on positron emission tomography (PET)-CT scanners requires the involvement of radiotherapy radiographers. This study assessed the radiation dose received by these radiographers during this process. Radiotherapy planning F- fluorodeoxyglucose (F-FDG) PET-CT scans were acquired for 28 non-small cell lung cancer patients. In order to minimise the radiation dose received, a two-stage process was used in which the most time-consuming part of the set-up was performed before the patient received their F-FDG injection. Throughout this process, the radiographers wore electronic personal dosemeters and recorded the doses received at different stages of the process. The mean total radiation dose received by a radiotherapy radiographer was 5.1±2.6 mSv per patient. The use of the two-stage process reduced the time spent in close proximity to the patient by approximately a factor of four. The two-stage process was effective in keeping radiation dose to a minimum. The use of a pre-injection set-up session reduces the radiation dose to the radiotherapy radiographers because of their involvement in PET-CT radiotherapy treatment planning scans by approximately a factor of three.

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A key to success in many sports stems from the ability to anticipate what a player is going to do next. In sporting duels such as a 1 vs. 1 in rugby, the attacker can try and beat the defender by using deceptive movement. Those strategies involve an evolution of the centre of mass (COM) in the medio-lateral plane, from a minimal state to maximal displacement just before the final reorientation. The aim of this work is to consider this displacement as a motion-gap, as outlined in Tau theory, as a potential variable that may specify deceptive movement and as a means of comparing anticipatory performance between mid-level players and novices in rugby. Using a virtual reality set-up, 8 mid-level rugby players (ML) and 8 novices (NOV) observed deceptive (DM) and non-deceptive movements (NDM). The global framework used an occlusion time paradigm with four occlusion times. Participants had to judge the final direction of the attacker after the different cuts-off. For each movement and at each occlusion time, we coupled the ability to predict the good final direction with the value of the COM displacement in the medio-lateral (COM M/L) plane or with the Tau of this parameter (Tau COM). Firstly, results show that the Tau COM is a more predictive optical variable than the simple COM M/L. Secondly, this optical variable Tau COM is used by both groups, and finally, with a specific methodology we showed that mid-level players have significantly better anticipatory ability than the novice group.

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This paper explores how the surface permeability of sandstone blocks changes over time in response to repeated salt weathering cycles. Surface permeability controls the amount of moisture and dissolved salt that can penetrate in and facilitate decay. Connected pores permit the movement of moisture (and hence soluble salts) into the stone interior, and where areas are more or less permeable soluble salts may migrate along preferred pathways at differential rates. Previous research has shown that salts can accumulate in the near-surface zone and lead to partial pore blocking which influences subsequent moisture ingress and causes rapid salt accumulation in the near-surface zone.

Two parallel salt weathering simulations were carried out on blocks of Peakmoor Sandstone of different volumes. Blocks were removed from simulations after 2, 5, 10, 20 and 60 cycles. Permeability measurements were taken for these blocks at a resolution of 20 mm, providing a grid of 100 permeability values for each surface. The geostatistical technique of ordinary kriging was applied to the data to produce a smoothed interpolation of permeability for these surfaces, and hence improve understanding of the evolution of permeability over time in response to repeated salt weathering cycles.

Results illustrate the different responses of the sandstone blocks of different volumes to repeated salt weathering cycles. In both cases, after an initial subtle decline in the permeability (reflecting pore blocking), the permeability starts to increase — reflected in a rise in mean, maximum and minimum values. However, between 10 and 20 cycles, there is a jump in the mean and range permeability of the group A block surfaces coinciding with the onset of meaningful debris release. After 60 cycles, the range of permeability in the group A block surface had increased markedly, suggesting the development of a secondary permeability. The concept of dynamic instability and divergent behaviour is applied at the scale of a single block surface, with initial small-scale differences across a surface having larger scale consequences as weathering progresses.

After cycle 10, group B blocks show a much smaller increase in mean permeability, and the range stays relatively steady — this may be explained by the capillary conditions set up by the smaller volume of the stone, allowing salts to migrate to the ‘back’ of the blocks and effectively relieving stress at the ‘front’ face.

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ARK (‘Access Research Knowledge’) was set up with a single goal: to make social science information on Northern Ireland available to the widest possible audience. The most well-known and widely used part of the ARK resource is CAIN (Conflict Archive on the INternet), which is one of the largest on-line collections of source material and information and about the Northern Ireland conflict. The compilation of CAIN's new Remembering: Victims, Survivors and Commemoration section raised issues related to the sensitivity of the material, as it feeds into the fundamental debate on the legacy of the Northern Ireland conflict. It also fundamentally raises the question to what extent archiving is a neutral or political activity and necessitates a discourse on responsibility and ethics among social researchers. Experiences from the establishment of the Northern Ireland Qualitative Archive (NIQA) shed light on future possibilities with regard to qualitative archives on the Northern Ireland conflict.

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In spite of intensive research, computational modeling of the injection stretch blow molding (ISBM) still cannot match the accuracy of other polymer processes such as injection molding. There is a lack of understanding of the interdependence among the machine parameters set up by the operators, process parameters, material behavior, and the resulting final thickness distribution and performance of the molded product. The work presented in this paper describes a set of instrumentation tools developed for investigation of the ISBM process in an industrial setting. Results are presented showing the pressure and air temperature evolution inside the mold, the stretch rod force and displacement history, and the moment of contact of the polymer with seven discrete locations on the mold.

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This paper reports the findings of an evaluation of the ‘Housing Support, Outreach and Referral’ service developed to support people living with HIV who were homeless or at risk of homelessness. The service was set up as part of the Supporting People Health Pilot programme established to demonstrate the policy links between housing support services and health and social care services by encouraging the development of integrated services. The paper considers the role of housing support in improving people's health, and considers the challenges of working across housing, health and social care boundaries. The evaluation of the health pilot employed two main sources of data collection: quarterly project evaluation reports, which collected process data as well as reporting progress against aims and objectives, and semi-structured interviews with professionals from all key stakeholder groups and agencies, and with people who used services. Over the course of 15 months, 56 referrals were received of which 27 were accepted. Fifteen people received tenancy support of whom 12 were helped to access temporary accommodation. At the end of the 15 months, all of the tenancies had been maintained. In addition, 18 people registered with a general practitioner and 13 registered with an HIV clinic. Interviews with professionals emphasised the importance of the local joint working context, the involvement of the voluntary sector and the role of the support workers as factors that accounted for these outcomes. Those using services placed most emphasis on the flexibility of the support worker role. Importantly, interviews with professionals and those using services suggest that the role of support worker incorporates two dimensions – those of networker/navigator as well as advocate – and that both dimensions are important in determining the effectiveness of the service.

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The characteristics of an extreme-ultraviolet (XUV) continuum light source and its application to a dual-laser plasma (DLP) photoabsorption experiment are described. The continuum emitting plasma was formed by focusing a 7 ps, 248 nm, 15 mJ laser pulse onto a number of selected targets known to be good XUV continuum emitters (Sm, W, Au and Pb), while the second absorbing plasma was produced by a 15 ns, 1064 nm, 300 mi pulse. The duration of the continuum emission for these plasmas has a mean value of similar to 150 ps, but depends on both the target material and the picosecond laser pulse energy. Using this picosecond DLP set-up we have been able to measure the photoabsorption spectrum of an actinide ion (thorium) for the first time.

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A half-cavity using a multilayer mirror has been set up close to the end of a large gain germanium-target system. An unambiguous saturation behaviour of the 232 angstrom and 236 angstrom lines has been observed. The role of the cavity mirror in this result is discussed. Suggestions are made for practical applications of an XUV laser in this wavelength range.

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In the financially precarious period which followed the partition of Ireland (1922) the Northern Irish playwright George Shiels kept The Abbey Theatre, Dublin, open for business with a series of ‘box-office’ successes. Literary Dublin was not so appreciative of his work as the Abbey audiences dubbing his popular dramaturgy mere ‘kitchen comedy’. However, recent analysts of Irish theatre are beginning to recognise that Shiels used popular theatre methods to illuminate and interrogate instances of social injustice both north and south of the Irish border. In doing so, such commentators have set up a hierarchy between the playwright’s early ‘inferior’ comedies and his later ‘superior’ works of Irish Realism. This article rejects this binary by suggesting that in this early work Shiels’s intent is equally socially critical and that in the plays Paul Twyning, Professor Tim and The Retrievers he is actively engaging with the farcical tradition in order to expose the marginalisation of the landless classes in Ireland in the post-colonial jurisdictions.

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Narrative, by its very nature, is changing as a consequence of internet developments. Hypertexts are, for example, changing not just the way in which we disseminate information, but also the ways in which we write, speak and think. In this paper a narrative approach is taken to assess a case study of a person’s extensive home site on the web. Bill maintains an extensive web site documenting his life with Parkinson’s Disease, his love for running and all matters relating to the island of Montserrat in the Eastern Caribbean. Bill’s Parkinson’s Disease hypertext diary forms the focus of this case study of a life spent on-line. Though set up just as a diary about this progressively degenerative disease, because of its hypertextual qualities, this paper argues that it is through the diary that Bill comes to produce and sustain - to narrate - his identity. This paper thus contributes to the position that though hypertext encourages the construction of fragmented and false identity narratives, it is also a medium for sustaining linear and coherent representations of self-identity.

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The rate and type of biological colonization of stone is influenced by a wide array of environmental factors in addition to substrate characteristics. A series of experiments was designed to compare the rate and type of biological colonization of stone at varying locations over a 21-month time period. Exposure
trials were set up at nine different sites across Northern Ireland that covered a wide variety of environmental conditions. To determine aspect-related differences in colonization, blocks of Peakmoor sandstone and Portland limestone were placed on the north- and south-facing sides of purpose-designed exposure racks. Colorimetry and visual analysis were carried out on collected samples at increasing time intervals. Results showed significantly different rates of darkening and greening over time between north-facing and south-facing blocks, for both sandstone and limestone. This difference is likely to be representative of the fact that in Northern Ireland’s wet climate and northern-latitude position, the north face of a building will receive less direct sunlight. Therefore north-facing blocks, once wet, will remain damp for much longer than blocks on other façades. This slow-drying phenomenon is much more hospitable for biological colonization and continued growth than the hostile environment of rapid wetting and drying cycles experienced on the south face.