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We have developed a probe to measure specific heat of Gd-doped PbMo(_6)S(_8), at low temperatures in high magnetic fields up to 12.5 T using a heat pulse method and an a.c. technique. Comparison between these heat capacity measurements and transport measurements provides critical complimentary information about fundamental thermodynamic properties and granularity m superconductors. We have used a tiny, robust, highly sensitive and broadly field independent Cemox thermometer (CX-1030), eliminating the use of bulky gas thermometry or capacitance thermometry. The diameter of the probe is 20 min which facilitates use in our 17 T high field magnet and in free-standing cryostats. Experiments include accurate measurement of temperature oscillations of 10(^-6)K. The measurements and analysis of the data were made fully computer controlled. Measurements on Cu and NbTi demonstrate we achieved an accuracy of ±0.2 K in temperature and a typical accuracy of -10% m the specific heat values quoted. Gd-doped Lead Chevrel phase material Pb(_1-x)Gd(_x)Mo(_6)S(_8) has been fabricated in a controlled environment using simple sintering methods and a Hot Isostatic Press (HIP) operating at pressures up to 2000 atmospheres. Cp has been measured and the properties of the materials including B(_c2)(T) have been determined. HIP processing improves the materials, increasing Tc ~ 15 K and B(_c2)(0) ~ 60 T. These values are amongst the best reported values for the Chevrel phase materials to date. I am personally responsible for taking all the data and its analysis. The modification of the probe were also undertaken by me. The fabrication of the samples was not my work

Iceland has long been thought to be underlain by a thermal upwelling, or plume, rising from deep within the mantle. This study tests this hypothesis, by a) seeking evidence for a plume in the lower mantle in azimuth anomalies at the NORSAR array and b) mapping the three-dimensional structure of the mantle beneath Iceland using teleseismic tomography and data from an Iceland-wide broadband seismometer network. A temporary network of 30 digital broadband, three-component seismographs was deployed 1996-1998 to complement the existing, permanent seismic network on Iceland. This created a dense, well-distributed network. 3159 P-wave and 1338 S-wave arrival times were measured and inverted for velocity structure using the ACH method of teleseismic tomography. The preferred models are well-resolved down to -400 km, and reveal a low-velocity body with anomaly up to -2.9% in V(_p)) and -4.9% in V(_s) beneath central Iceland. This persists throughout the entire model depth range. The amplitudes of the anomalies imply an excess temperature of 200-300 K relative to the surrounding mantle. The morphology of the anomaly changes from cylindrical to tabular at 250-300 km depth, a feature that resolution tests suggest is real. This is consistent with the predictions of some convection models and suggests that the plume is restricted to the upper mantle. Anomalies in v(_p) and v(_s) provide evidence for lateral flow of material beneath the Reykjanes Ridge to the southeast in the depth range 50-200 km. Similar anomalies are present beneath the Kolbeinsey Ridge to the north only beneath 160 km. This shows that flow outwards beneath the Kolbeinsey Ridge is blocked by the Tjörnes Fracture Zone above 160 km. Azimuthal anomalies detected on the NORSAR array for rays travelling beneath Iceland at 1,500 km depth are consistent with a plume beneath Iceland at this lower-mantle depth with a Gaussian radius of 125 km and a strength of 1.5%. The observations do not serve as proof for such an anomaly because the solution is not unique. V(_p)/V(_s) ratios are 1% high throughout most of the plume, and up to 3.2% high at depths of 100-300 km beneath central and east-central Iceland. This suggests that up to a few percent of melt pervades the entire plume.

Spacecraft thermal design is an inverse problem that requires one to determine the choice of surface properties that yield a desired temperature distribution within a satellite. The current techniques for spacecraft thermal design are very much in the frame of trial and error. The goal of this work is to move away from that procedure, and have the thermal design solely dependent on heat transfer parameters. It will be shown that the only relevant parameters to attain this are ones which pertain to radiation. In particular, these parameters are absorptivity and emissivity. We intend to utilize an optimal/analytical approach, and obtain a solution via optimization. As mentioned in the motivation, having a purely passive thermal system will greatly reduce costs, and our optimization solution will enable that. This topic involves heat transfer (conduction and radiation), spacecraft thermal network models, numerical optimization, and materials selection.

Air-conditioning systems driven by solar energy have can save primary energy and reduce peak power consumption, which is particularly important for utility providers in the summer months. Additionally solar cooling is a promising application of solar thermal technology since the cooling load is well correlated to the overall solar availability. Liquid desiccant air-conditioning, which uses a salt solution to dehumidify air, can be used in a thermally driven air-conditioning system and offers many benefits for solar applications including the ability to store solar energy in the form of concentrated liquid desiccant. The current work focuses on the Queen’s University Solar Liquid Desiccant Cooling Demonstration Project. In previous work, a pre-commercial Liquid Desiccant Air Conditioner (LDAC) was installed and experimentally characterized using a gas-fired boiler to provide heat. As part of the current study a 95m2 solar array was added as a heat source. The Solar LDAC was tested for 20 days in the summer of 2012 to evaluate performance. The solar LDAC was found to provide between 9.2kW and 17.2kW of cooling power with an overall thermal Coefficient of Performance (COP) of 0.40 and electrical COP of 2.43. The collector efficiency was 53%, and 40% of the required thermal energy was provided by the solar array. A model was developed in TRNSYS to predict the performance of the solar LDAC and simulation results were compared to the experimental results with reasonable accuracy. The validated model was then used to simulate the annual performance of the solar LDAC in Toronto, Ontario; Vancouver, British Columbia; and Miami, Florida. The highest performance was achieved in Miami, where an overall thermal COP of 0.48 was predicted. It is proposed that additional improvements be made to the system by replacing inefficient pumps and fans, adding desiccant storage, and improving the control scheme. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2012-10-29 16:34:02.906

PV/Thermal technology is the combination of solar thermal and photovoltaics - two mature and widely understood technologies. Combining the two technologies complicates existing standardized rating procedures and performance modeling methods. Currently a standardized performance test method does not exist for PV/Thermal (PV/T) panels. Existing and developing PV/T panels are commonly tested using separate standardized solar thermal and photovoltaic test procedures. Solar thermal performance is rated in terms of temperature difference whereas photovoltaic performance is dependent on absolute temperature level. The thermal and electrical performance of a PV/T panel is, however, coupled so performance equations derived using traditional test methods may not accurately reflect the performance of a combined PV/T panel over a wide range of conditions. The purpose of this work was to develop an efficiency equation for a PV/T panel which can be derived from a minimal amount of empirical test data and still accurately predict its thermal and electrical performance over a wide range of conditions. To accomplish this, a quasi- 3-dimensional steady-state model of a sheet-and-tube PV/T collector was developed and used to generate a broad data set from which a simplified PV/T performance equation was developed. Using this numerically generated data set, and introducing additional coefficients into the traditional solar thermal performance characteristic, a modified PV/T efficiency equation was derived which expressed the electrical and thermal efficiency in terms of ambient temperature, incident solar irradiation and the temperature difference between the inlet fluid and the ambient. It was also shown, for the case studied, that the efficiency equation can be produced from as few as 6 data points and still accurately predicts the performance at a wide range of operating conditions. A TRNSYS [1] model was developed to demonstrate how the performance equation can be used to simulate the annual performance of a PV/T collector in a domestic hot water system. It was shown that a performance equation, derived from 6 data points, performed as well as a performance map which used over 1000 data points. The annual thermal and electrical production predicted by both models was within 1.5% of each other. The PV/T efficiency equations were also shown to perform well for a range of electrical parameters, thermal properties and substrate thermal conductivity values. Future work is recommended to validate the PV/T performance equation using real empirically derived data for a range of collector designs. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2013-01-22 15:40:03.337

This thesis reports a summary of the PhD programme for the assessment of person‘s emotional anxiety using Electro-optical technology. The thesis focuses mainly on the understanding of fundamental properties of physiological responses to emotional anxiety and how they can be captured by using Electro-optical (EO) imaging methods such as hyperspectral imaging (HSI) and thermal imaging (TI) techniques. The thesis summarises three main areas of work that have been undertaken by the author in the programme: (a) Experimental set up including HSI system and data acquisition software design and implementation, (b) fundamental understanding of physiological responses to emotional anxiety from the EO perspective and (c) the development of a novel remote sensing technique for the assessment of emotions without the requirement of base line information. One of our main results is to provide evidence to prove that the mean temperature in the periorbital region remains the same within 0.2°C during emotional anxiety. Furthermore, we have shown that it is the high temperature pixels within the periorbital, which increases in numbers by a huge amount after 2 minutes of the onset of anxiety. We have also developed techniques to allow the assessment anxiety without the need of base line information. The method has been tested using a sample size of about 40 subjects, and achieved promising result. Technologies for the remote sensing of heart beat rate has been in great demand, this study also involves the development of heart beat detection using TI system. Moreover, we have also attempted for the first time to sense glucose concentration from the blood sample in-vivo using HSI technique remotely.

This thesis reports research to investigate the mechanical, thermal and acoustic properties of biodegradable foams in block forms based on wheat starch and developed at Brunel University's School of Engineering & Design, in order to exploit the potential environmental benefits of this renewable and biodegradable class of materials. Two emergent novel technologies have been developed based on a combination of the extrusion foaming of starch in conjunction with the natural adhesive characteristics of moistened starch to produce block foams. Regular Packing & Stacking (RPS), and Compression Bonded Loosefill (CBL), are foam fabrication technologies which have both demonstrated the potential to produce bulk foams based on wheat starch with unique structures and properties - a new class of foam materials in the form of macro-composites reinforced by a network of high-density bonding interfaces. This thesis, as part of a Department of Trade & Industry/Technology Strategy Board funded project, reports an investigation into the following areas to address the scientific and technical issues involved in the further development of the materials and their applications. - The basic properties of the raw materials used in the manufacture of CBL and RPS foams are outlined and the fabrication and preparation of these starch-based foams are described. The limitations of these production techniques are discussed with preliminary work and suggestions made for their enhancement. - Research into the mechanical properties of the CBL and RPS foams includes compression, tensile, creep and dynamic impact tests, whilst the mechanical behaviour of the foams subject to high temperature and high humidity conditions is also reported. - Research into the thermal properties of CBL and high density RPS foams includes testing of the material's thermal conductivity. This aspect of the research also involved a case study detailing the use of RPS in a commercial thermal insulation application. - Research into the acoustic properties of CBL and RPS foams includes tests for sound absorption coefficient and sound transmission loss. - Data obtained from these tests are benchmarked against data pertaining to the mechanical, thermal and acoustic properties of conventional polymer foams in order to provide a basis on which to identify the potential cushioning, thermal insulation and acoustic insulation applications of the starch-based materials. The research has demonstrated the following: - Potential cushioning applications include those limited to the range of static loads within the capabilities of the materials, taking into account the resilience of CBL and RPS which is likely to be compromised by successive impacts. - Tensile forces tend to exploit weaknesses in the macrostructure of these materials. By implication the behaviour of the materials under shear forces would be expected to be similarly compromised. - CBL and RPS exhibited dimensional shrinkage, density increase and significantly reduced mechanical properties under conditions of high temperature and humidity. This suggests that neither CBL nor RPS foams would be suitable for applications in regions where tropical conditions may be encountered unless used in conjunction with other protective materials which would not acutely increase the environmental burden of the products. - Low-density RPS and CBL foams exhibit lower thermal conductivities and hence higher thermal insulation properties compared to many commercially available polymer foams of similar densities. As such these foams have the potential to be used in applications in which a measure of thermal insulation is required. A case study based on an existing commercial application in which the temperature of chilled products must be maintained over a 24 hour period reinforced these findings. - The performance of CBL and RPS starch foams would not provide sufficient functionality to be employed in applications in which dedicated acoustic performance is required, although their sound absorption capabilities may facilitate overall marketability for applications in which a degree of acoustic performance is required if used in conjunction with other materials which demonstrate good acoustic performance. It is anticipated that this work will make significant contributions toward advances in the development of these novel technologies, specifically in terms of establishing an understanding of the properties of the starch-based materials and in identifying potential applications. The research results should thus provide a fundamental element in the basis for the industrial development of these renewable and biodegradable materials.

The project consists of controlling a mechanical piston and thermal resistance using an Arduino’s microcontroller. The piston and the thermal resistance take part of an existing project. This project, known as The electronic nose, has the purpose to measure the aroma of different products. In order to achieve this purpose, this tool is a combination of various sensors used to detect gases by generating signals for an analysis system. The project can be divided in different parts; electrical circuit design of piston and thermal resistance, design mechanical parts and components needed, develop a software able to control the piston and the thermal resistance and communication between software. The piston is installed on the bottom part of hollow cylindrical case and the thermal resistance is located inside a cylindrical base. This base, where the sample for smelling is put up, is bound on the top of the piston. Arduino controls the piston up and down movement and the temperature in the sample’s base. On the other hand, the electronic nose is installed at the top of the case. Through its sensors, The electronic nose is able to measure the aroma of some products. The aroma comes from the gases of the sample and they can be detected by the sensors. The purpose of installing the piston in the electronic nose is to get a pulse signal during the measure of these gases. Moreover, is very important keep the temperature of the sample under control, therefore the software is based on a on/off controller. A on/off controller calculates continuously the difference between a desired temperature set point and the temperature measured during process. In order to minimize this difference value the controller turn on or off the resistance during a specific instant time.