Production of Hyperpolarised 129Xe for NMR Spectroscopy and Imaging

Hyperpolarised 3He has been used extensively in the neutron community and for magnetic resonance imaging (MRI) of the lungs. 129Xe has many desirable advantages compared to 3He for NMR, namely its chemical sensitivity, solubility, adsorption capability and atmospheric abundance. In this work we present the design and construction of a 129Xe spin exchange polariser that operates at gas pressures between 0.6 and 3 bar. The design incorporates a novel Volume Holographic Grating (VHG) spectrally narrowed, high power laser diode device as the optical pump source for a continuous gas flow cylindrical polarisation cell. Nuclear polarisations of 34 +/- 3 % are achieved in 129Xe gas. Magnetisation production factors in excess of 80 % cm^3 min^-1 are achieved using a pseudo batch-flow operation method. Major parameters affecting 129Xe gas polarisation are discussed and the first measurements of cell heating from laser light absorption by Rb vapour are made. Hyperpolarised 129Xe gas produced from our system is imaged inside a low field, whole body MRI scanner. NMR measurements from inside a human lung are made using hyperpolarised 129Xe. Preliminary work on dissolved solution NMR is presented as are studies on the feasibility of using hyperpolarised 129Xe for porosity characterisation of porous media in low magnetic fields

Cleaning assurance for reusable plastic packaging using ultraviolet induced fluorescence

Implementing reusable packaging systems is one approach that could reduce the global consumption of single use plastics. Clearly, it is important to ensure that reusable packaging undergoes a process of cleanliness assurance before it is refilled. This research seeks to demonstrate the feasibility of an optical sensing technique to provide this assurance for polymer drinks bottles. An ultraviolet illumination source is used to induce fluorescence in both common polymer and fouling samples. The responses, captured by digital imaging, are processed to determine features that can be used to differentiate the packaging and fouling substances. Variation in signal intensity and differences in responses in the red, green and blue channels are identified as suitable features to enable detection of foulin

Production of Hyperpolarised 129Xe for NMR Spectroscopy and Imaging

Hyperpolarised 3He has been used extensively in the neutron community and for magnetic resonance imaging (MRI) of the lungs. 129Xe has many desirable advantages compared to 3He for NMR, namely its chemical sensitivity, solubility, adsorption capability and atmospheric abundance. In this work we present the design and construction of a 129Xe spin exchange polariser that operates at gas pressures between 0.6 and 3 bar. The design incorporates a novel Volume Holographic Grating (VHG) spectrally narrowed, high power laser diode device as the optical pump source for a continuous gas flow cylindrical polarisation cell. Nuclear polarisations of 34 +/- 3 % are achieved in 129Xe gas. Magnetisation production factors in excess of 80 % cm^3 min^-1 are achieved using a pseudo batch-flow operation method. Major parameters affecting 129Xe gas polarisation are discussed and the first measurements of cell heating from laser light absorption by Rb vapour are made. Hyperpolarised 129Xe gas produced from our system is imaged inside a low field, whole body MRI scanner. NMR measurements from inside a human lung are made using hyperpolarised 129Xe. Preliminary work on dissolved solution NMR is presented as are studies on the feasibility of using hyperpolarised 129Xe for porosity characterisation of porous media in low magnetic fields

The Changing Landscape of Energy Management in Manufacturing

The production and use of energy accounts for around 60% of global greenhouse gas (GHG) emissions, providing an intrinsic link between cause and effect. Considering that the manufacturing industry is responsible for roughly one-third of the global energy demand enforces the need to ensure that the manufacturing sector continually strives to reduce its reliance on energy and thus minimise GHG released into the atmosphere. Consequently, efficient management of energy consumption is of paramount importance for modern manufacturing businesses due to well-documented negative impacts regarding energy generation from fossil fuels and rapidly rising worldwide energy costs. This has resulted in a proliferation of research in this area which has considered improvements in energy consuming activities at the enterprise, facility, cell, machine and turret levels. However, there is now a need to go beyond incremental energy efficiency improvements and take more radical approaches to reduce energy consumption. It is argued that the largest energy reduction improvements can be achieved through better design of production systems or by adopting new business strategies that reduce the reliance of manufacturing businesses on resource consumption. This chapter initially provides a review of research in energy management (EM) at various manufacturing focus levels. The inappropriateness of current methods to cater for transformative and radical energy reduction approaches is discussed. In particular, limitations are found at the business strategy level since no technique exists to consider the input of these high level decisions on energy consumption. The main part of the chapter identifies areas of further opportunity in energy management research, and describes a method to facilitate further reductions in energy use and GHG production in manufacturing at the business strategy level

Tool state assessment for reduction of life cycle environmental impacts of aluminium machining processes via infrared temperature monitoring

Modern industrial machining environments face new challenges in implementing process monitoring systems to improve energy efficiency whilst ensuring quality standards. A process monitoring methodology for tool state identification during milling of aluminium has been implemented through the utilisation of an infrared (IR) camera. A features extraction procedure, based on statistical parameters calculation, was applied to temperature data generated by the IR camera. The features were utilised to build a fuzzy c-means (FCM) based decision making support system utilising pattern recognition for tool state identification. The environmental benefits deriving from the application of the developed monitoring system, are discussed in terms of prevention of rework/rejected products and associated energy and material efficiency improvements

Complex beam profiles for laser annealing of thin-film CdTe photovoltaics

Within the family of thin-film photovoltaics (PV), cadmium telluride (CdTe) has the fastest growing market share due to its high efficiencies and low cost. However, as with other PV technologies, the energy required to manufacture the panels is excessive, encompassing high environmental impact and manufacturing energy payback times of the order of 2-3 years. As part of the manufacturing process, the panels are annealed at temperatures of approximately 400°C for 30 minutes, which is inherently inefficient. Laser heating has previously been investigated as an alternative process for thin film annealing, due to its advantages with regard to its ability to localise heat treatment, anneal selectively and its short processing time. In this investigation, results focussing on improvements to the laser-based annealing process, designed to mitigate panel damage by excessive thermal gradients, are presented. Simulations of various laser beam profiles are created in COMSOL and used to demonstrate the benefit of laser beam shaping for thin film annealing processes. An enabling technology for this, the holographic optical element (HOE), is then used to experimentally demonstrate the redistribution of laser beam energy into an optimal profile for annealing, eliminating thermal concentrations

Intelligent Industrial Cleaning: A Multi-Sensor Approach Utilising Machine Learning-Based Regression

Effectively cleaning equipment is essential for the safe production of food but requires a significant amount of time and resources such as water, energy, and chemicals. To optimize the cleaning of food production equipment, there is the need for innovative technologies to monitor the removal of fouling from equipment surfaces. In this work, optical and ultrasonic sensors are used to monitor the fouling removal of food materials with different physicochemical properties from a benchtop rig. Tailored signal and image processing procedures are developed to monitor the cleaning process, and a neural network regression model is developed to predict the amount of fouling remaining on the surface. The results show that the three dissimilar food fouling materials investigated were removed from the test section via different cleaning mechanisms, and the neural network models were able to predict the area and volume of fouling present during cleaning with accuracies as high as 98% and 97%, respectively. This work demonstrates that sensors and machine learning methods can be effectively combined to monitor cleaning processes

An overview of resilience factors in food supply chains

Food supply chains face a number of unique vulnerabilities compared to other supply chains and there is concern that, as operating environment volatility increases, current “lean” supply chain management strategies may no longer be fit for purpose. There is a need to manage food supply chains in such a way that a return to the original state, or preferably an improved state, after being disturbed is possible. However, whilst the literature reveals a relatively large amount of work on resilience in supply chain management, there is poor consensus over how to define and implement a system of resilience, particularly one which takes into account food specific vulnerabilities. In response, this paper explores the current complexity of food supply chains, highlighting key dependencies, failure modes and key performance indicators. It then examines the interdependencies between capabilities and vulnerabilities in allowing balanced resilience and presents a framework to bring together and aid understanding of these factors across food supply chains

Towards integrating production and consumption to reduce consumer food waste in developed countries

Literature analysing reasons for Consumer Food Waste (CFW) revealed that it cannot be reduced to individual consumer behaviour alone. In fact, CFW should not be conceptualised as the problem but as a symptom of a food system that oversupplies and encourages consumerism. This research focuses on preventing CFW generated in the United Kingdom (UK), as a representative of a developed country, by improving the traditional food provisioning system to better integrate production and consumption. To achieve this, five stages are identified to design a sustainable product service system (PSS) capable of supporting consumers to better manage their food operations. These are: (1) strategic analysis of current food provisioning system, (2) exploring system level innovations leading to significant minimisation of CFW, (3) refinement and selection of PSS, (4) designing the most promising PSS concept from an environmental, economic and social perspective, and (5) evaluating designed PSS against current food provisioning system. This paper considers the first of these stages, reviews reasons for and existing solutions to CFW, and provides a strategic analysis of the current food provisioning system to identify characteristics that could be exploited within a new PSS to reduce CFW. Initial investigations reveal applicability of PSS concept to the food provisioning system and potential for considerable reduction of CFW if core causes are adequately addressed

Optimising industrial food waste management

Global levels of food waste are attracting growing concern and require immediate action to mitigate their negative ecological and socio-economic ramifications. In the developed world, of the order of 20-40% of food waste is generated at the manufacturing stage of supply chains and is often managed in non-optimised ways leading to additional environmental impacts. This research describes a novel decision-support tool to enable food manufacturers to evaluate a range of waste management options and identify the most sustainable solution. A nine-stage qualitative evaluation tool is used in conjunction with a number of quantitative parameters to assess industrial food waste, which is then used to generate performance factors that enable the evaluation of economic, environmental and social implications of a range of food-waste management alternatives. The applicability of this process in a software-based decision-support tool is discussed in the context of two industrial case studies