Improvements in temperature measurement

This submission for the degree of Doctor of Science describes work initiated, led or contributed to by Dr Graham Machin, a graduate of the University of Birmingham, over the last 25 years. The submission comprises of six main parts, illustrating the different contributions made to the area of temperature measurement. In brief these are: • Development and improvement of non-contact thermometry standards • Comparisons of non-contact thermometry scales, including the development of new methods of comparison • Contributions to the development of high temperature fixed points as new temperature references above the freezing point of copper (1 084.62 °C) • Development of methods for the mitigation of temperature sensor drift at high temperatures • Improvements and innovations in medical thermometry - in a variety of settings • Leadership in international temperature measurement research The thesis begins with an introduction to the subject of the research, including a brief overview of the presented papers. Then a list of the presented papers is given followed by copies of the manuscripts. The thesis ends with an Appendix containing an up to date publication record

Re-estimation of argon isotope ratios leading to a revised estimate of the Boltzmann constant

In 2013, NPL, SUERC and Cranfield University published an estimate for the Boltzmann constant [1] based on a measurement of the limiting low-pressure speed of sound in argon gas. Subsequently, an extensive investigation by Yang et al [2] revealed that there was likely to have been an error in the estimate of the molar mass of the argon used in the experiment. Responding to [2], de Podesta et al revised their estimate of the molar mass [3]. The shift in the estimated molar mass, and of the estimate of kB, was large: -2.7 parts in 106, nearly four times the original uncertainty estimate. The work described here was undertaken to understand the cause of this shift and our conclusion is that the original samples were probably contaminated with argon from atmospheric air.
 In this work we have repeated the measurement reported in [1] on the same gas sample that was examined in [2, 3]. However in this work we have used a different technique for sampling the gas that has allowed us to eliminate the possibility of contamination of the argon samples. We have repeated the sampling procedure three times, and examined samples on two mass spectrometers. This procedure confirms the isotopic ratio estimates of Yang et al [2] but with lower uncertainty, particularly in the relative abundance ratio R38:36.
 Our new estimate of the molar mass of the argon used in Isotherm 5 in [1] is 39.947 727(15) g mol-1 which differs by +0.50 parts in 106 from the estimate 39.947 707(28) g mol-1 made in [3]. This new estimate of the molar mass leads to a revised estimate of the Boltzmann constant of kB = 1.380 648 60 (97) × 10−23 J K−1 which differs from the 2014 CODATA value by +0.05 parts in 106.&#13

Improving recognition of anxiety and depression in rheumatoid arthritis: a qualitative study in a community clinic.

BACKGROUND: Comorbid anxiety and depression are common in patients with rheumatoid arthritis (RA) but are often under-recognised and treated, contributing to worse outcomes. National Institute for Health and Care Excellence (NICE) recommends that patients with RA should be offered a holistic annual review, including an assessment of mood. AIM: To explore patients' perspectives of anxiety and depression in RA and preferences for disclosure and management of mood problems. DESIGN AND SETTING: Qualitative interview study with patients recruited from a nurse-led RA annual review clinic in the Midlands, England. METHOD: Patients attending the clinic who scored ≥3 on the case-finding questions (PHQ-2 and GAD-2) were invited for interview. Data were analysed thematically using principles of constant comparison. RESULTS: Participants recognised a connection between their RA and mood, though this was perceived variably. Some lacked candidacy for care, normalising their mood problems. Fear of stigmatisation, a lack of time, and the perception that clinicians prioritise physical over mental health problems recursively affected help-seeking. Good communication and continuity of care were perceived to be integral to disclosure of mood problems. Participants expressed a preference for psychological therapies, though they reported problems accessing care. Some perceived medication to be offered as a 'quick fix' and feared potential drug interactions. CONCLUSION: Prior experiences can lead patients with RA and comorbid anxiety and depression to feel they lack candidacy for care. Provision of equal priority to mental and physical health problems by GPs and improved continuity of care could help disclosure of mood concerns. Facilitation of access to psychological therapies could improve outcomes for both mental and physical health problems

The INCLUDE study: INtegrating and improving Care for patients with infLammatory rheUmatological DisordErs in the community; identifying multimorbidity: Protocol for a pilot randomized controlled trial.

Background: Patients with inflammatory rheumatic conditions such as rheumatoid arthritis, polymyalgia rheumatica and ankylosing spondylitis are at increased risk of common comorbidities such as cardiovascular disease, osteoporosis and anxiety and depression which lead to increased morbidity and mortality. These associated morbidities are often un-recognized and under-treated. While patients with other long-term conditions such as diabetes are invited for routine reviews in primary care, which may include identification and management of co-morbidities, at present this does not occur for patients with inflammatory conditions, and thus, opportunities to diagnose and optimally manage these comorbidities are missed. Objective: To evaluate the feasibility and acceptability of a nurse-led integrated care review (the INtegrating and improving Care for patients with infLammatory rheUmatological DisordErs in the community (INCLUDE) review) for people with inflammatory rheumatological conditions in primary care. Design: A pilot cluster randomized controlled trial will be undertaken to test the feasibility and acceptability of a nurse-led integrated primary care review for identification, assessment and initial management of common comorbidities including cardiovascular disease, osteoporosis and anxiety and depression. A process evaluation will be undertaken using a mixed methods approach including participant self-reported questionnaires, a medical record review, an INCLUDE EMIS template, intervention fidelity checking using audio-recordings of the INCLUDE review consultation and qualitative interviews with patient participants, study nurses and study general practitioners (GPs). Discussion: Success of the pilot study will be measured against the engagement, recruitment and study retention rates of both general practices and participants. Acceptability of the INCLUDE review to patients and practitioners and treatment fidelity will be explored using a parallel process evaluation. Trial Registration: ISRCTN12765345

Smart Cities: Towards a New Citizenship Regime? A Discourse Analysis of the British Smart City Standard

Growing practice interest in smart cities has led to calls for a less technology-oriented and more citizen-centric approach. In response, this articles investigates the citizenship mode promulgated by the smart city standard of the British Standards Institution. The analysis uses the concept of citizenship regime and a mixture of quantitative and qualitative methods to discern key discursive frames defining the smart city and the particular citizenship dimensions brought into play. The results confirm an explicit citizenship rationale guiding the smart city (standard), although this displays some substantive shortcomings and contradictions. The article concludes with recommendations for both further theory and practice development

Practical Doppler broadening thermometry

We report initial research to develop a compact and practical primary thermometer based on Doppler broadening thermometry (DBT). The DBT sensor uses an intrinsic property of thermalized atoms, namely, the Doppler width of a spectral line characteristic of the atoms being probed. The DBT sensor, being founded on a primary thermometry approach, requires no calibration or reference, and so in principle could achieve reliable long-term in-situ thermodynamic temperature measurement. Here we describe our approach and report on initial proof-of-concept investigations with alkali metal vapour cells. Our focus is to develop long-term stable thermometers based on DBT that can be used to reliably measure temperatures for long periods and in environments where sensor retrieval for re-calibration is impractical such as in nuclear waste storage facilities.Comment: 7 pages, 4 figures, referees' comments incorporate

Thermal modelling comparing high temperature fixed point measurements by contact and non-contact thermometry

This paper reports thermal modelling that aims to establish if the measurement method - either by a radiation thermometer or by a thermocouple - significantly influences the measured temperature of the high temperature fixed points Co-C, Pd-C and Ru-C. It is clear that both measurement techniques have specific physical characteristics which may affect the temperature measured during the melting plateau. With the radiation thermometer, the radiation heat transfer is directly influenced by the environment because the back-wall is effectively viewing the cold outside environment. In the case of a thermocouple direct viewing of the outside world is blocked so radiation transport is significantly reduced; however, in the case of the thermocouple there is a different component of heat transfer, namely conduction from the thermowell walls in contact with the thermocouple along the thermocouple stem itself

Potential for improved radiation thermometry measurement uncertainty through implementing a primary scale in an industrial laboratory

A primary temperature scale requires realising a unit in terms of its definition. For high temperature radiation thermometry in terms of the International Temperature Scale of 1990 this means extrapolating from the signal measured at the freezing temperature of gold, silver or copper using Planck’s radiation law. The difficulty in doing this means that primary scales above 1000 °C require specialist equipment and careful characterisation in order to achieve the extrapolation with sufficient accuracy. As such, maintenance of the scale at high temperatures is usually only practicable for National Metrology Institutes, and calibration laboratories have to rely on a scale calibrated against transfer standards. At lower temperatures it is practicable for an industrial calibration laboratory to have its own primary temperature scale, which reduces the number of steps between the primary scale and end user. Proposed changes to the SI that will introduce internationally accepted high temperature reference standards might make it practicable to have a primary high temperature scale in a calibration laboratory. In this study such a scale was established by calibrating radiation thermometers directly to high temperature reference standards. The possible reduction in uncertainty to an end user as a result of the reduced calibration chain was evaluated