Ammonia is the most prevalent alkaline gas in the atmosphere and plays an important role in environmental pollution through acidification and eutrophication. Livestock are the largest source of ammonia in the UK, mainly originating during storage and spreading of animal manure. The aim of this study was to validate the collection efficiency of recurved passive ammonia flux (PAF) samplers and the flux frame method to provide a robust methodology for measurement of distributed agricultural sources of ammonia outdoors. The collection efficiency of recurved PAF samplers was determined in a wind tunnel under controlled conditions of ammonia flux (0.771 - 13.49 mg NH3 m-2 s-1), and at angles of orientation to the flow direction (0, 30, 60, 70, 80, 90°). The samplers were effective up to a wind speed of 7 m s-1 and an angle of 80°, with a mean collection efficiency of 71%. The flux frame method had a mean collection efficiency of 87.4% when used with ground level point sources under controlled conditions in the Atmospheric Flow Laboratory. However, in controlled field releases, the efficiency fell to 56.4%. The flux frame method was also suitable for line sources, although assumptions must be made about the source homogeneity and plume dispersion. ADMS modelling was used to predict the collection efficiencies for the flux frame method and these agreed with measured collection efficiencies to within 37.3%. A comparison of source strengths determined using a full size flux frame and portions of the flux frame showed that a full size flux frame was unnecessary as one column of samplers produced a very similar estimate to that of the whole frame. The validated method was then used to measure ammonia emissions from free-range pigs. The amount of ammonia emitted from this source was very low and less than 0.16 g (kg of sow)-1 day-1.

In assessing the health risks posed from heavy metals in a contaminated site, it is important to determine when the contamination occurred and when the metals become available to the surrounding biota. Trees and plants growing in the vicinity of a contaminated site may provide such a historic record. There have been few studies on their role as biomarkers to identify metal mobility or bioavailability for continuous monitoring purposes. The aim of the study was to evaluate the role of plants as biomonitors for site characterisation and risk assessment purposes and to see if there was any selectivity between metal uptake in leaves and roots. Tree cores were also collected as metals in soil or ground water and may be drawn up via tree roots and deposited in the growth rings. This was examined using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LAICPMS) and Proton Induced X-Ray Emission (PIXE). From the plant analysis, the elements present in highest amount were lead, zinc and cooper. The mobility of lead could be monitored by bramble and nettle leaves; that of copper by nettle roots and bramble leaves and that of zinc by nettle roots, bramble and sycamore leaves. Analysis of tree cores by LAICPMS and PIXE showed a contrasting contaminant signature between the sampled trees, as there was inconsistency of metal concentrations within the same segment of growth ring. This variability may offer an insight into labile metal function within the tree physiology. The utility of using the dendrochemical record may best serve as an indicator of macro-environmental perturbations, rather than an indicator of labile metal chronologies, for which only lead showed a reasonably consistent decline through time, across the tree core record.

This project looks at the potential for re-use of quarry wastes, in particular, Hassock, from the Lower Greensand, Hythe Beds, which in one Ragstone quarry alone, amounts to 100,000 tonnes of material annually. Quarry wastes have been solidified with a range of other waste products including Cement Kiln Dust, Ground Granulated Blast-furnace Slag and Pulverized Fuel Ash. The mixes were subjected to a CO2 atmosphere for varying lengths of time, to determine their carbonation potential and optimum CO2 exposure time, in order to produce pellets with optimum strength, measured by Aggregate Impact Value. Pellets that had been hydrated before carbonated were stronger than those carbonated immediately. However, carbonating the mixes during pelletization was found to have a beneficial effect on final pellet strength. After further hydration in air for 6 weeks, the pH of these pellets was reduced considerably, when they were further carbonated for 24 hours in the CO2 chamber. Furthermore, strength was found to be substantially increased. The manufacture of these carbonated pellets will recycle CO2 and up to 4 waste streams and modify the quarry waste by reducing the dust component to a mere trace. The Aggregate Impact Value of pellets ranges from 14 to 19 and they have a bulk density of 1030 to 1100 kg/m3, making them potentially suitable for use as Light Weight Aggregates.

Rapid urbanization of cities has greatly modified the thermal and dynamic profile in the urban boundary layer. This thesis attempts to study the effect of urban heating on the local climate and air quality for a tropical coastal urban agglomeration, Greater Kuala Lumpur (GKL) in Malaysia. A state-of-art numerical model, Weather Research and Forecast Model (WRF) is used to identify the influence of urbanization through modification of urban surfaces. In order to thoroughly study the environmental impact of land use change in GKL, this thesis begins with the local urban heating on the surface layer before extending to the influence on the boundary layer circulation and its atmospheric composition. The WRF model is tested for its applicability to reproduce the urban heating condition. The model verification hence incorporates sensitivity analysis of physics pertinent to the simulation of land surface and boundary layer dynamics condition, namely the land use map, urban canopy model (UCM) and planetary boundary layer (PBL) physics options. Result shows that the urban surface representation and parameterization models in WRF are of great importance for the high resolution urban climate in the region. The locally calibrated land use map and urban parameters have substantially improved the near-surface weather and urban heating prediction. The local PBL scheme also predicts a generally good agreement for the studied region in terms of near-surface environment and vertical profile during the morning and evening transitional period. Incorporating the optimum physics settings, the control study found that urbanization due to land use change has induced a modelled daily mean urban heat island intensity (UHII) of 0.9 °C with a more severe heating of 1.9 °C at night. The heating condition induces urban thermal circulation that interacts with the local topographic flow, namely sea/land breeze and downhill/uphill breeze for the coastal urban agglomeration sheltered by the mountain ranges on the other side. Depending on the cloud cover and prevailing synoptic flow, the immense heat forcing on the surface accelerates/decelerates the moisture-bearing sea breeze during the day. It also induces vertical lifting which creates a conducive environment for convective precipitation on the upwind region. The subsequent control study with chemical weather prediction model (WRF-Chem) shows that the urban heating condition reduces the ground ozone level by around 20 ppbv throughout the day. Analysis shows that the reduced ozone level is closely correlated to the stronger horizontal sea breeze front (SBF) advection in the morning and urban-enhanced vertical mixing during the night which disperse the ground ozone and its precursors. Despite the reduction of ozone level, the air quality monitoring result identifies GKL as NOx-sensitive region which is prone to higher level of ozone with the continuous expansion of urban. The thesis explores the ability of WRF software to reproduce the high resolution urban climate. The model evaluation has realistically discovered that WRF is able to produce good approximation of the near-surface weather condition and fairly reasonable vertical boundary layer profiles. However, the atmospheric chemistry composition of the local surface pollutants is greatly underestimated. Continuous effort is required to improve the regional prediction on the chemistry weather prediction tool.

Non-degradable waste tire generation around the world is growing at an alarming rate. Diversifying the recycling route of these waste tires is essential to solve the problem. One way is to incorporate them into polymers and convert them into new products. However, incorporation of ground tire rubber into thermoplastics has been hampered due to lack of toughness and adhesion between phases. To address the issue, this study utilized reclaimed waste tire rubber (RTR) instead; and evaluated the properties of RTR and poly(ethylene-co-vinyl acetate) (EVA) blends. The properties of the RTR/EVA blends were further enhanced by compatibilization and electron beam irradiation. Processing, mechanical, thermal and dynamic mechanical properties of RTR were tremendously improved by blending with EVA. However, the interfacial adhesion was found to lack in the blends. Compatibilization by reactive, physical and combination strategies were explored utilizing (3-Aminopropyl)triethoxy silane (APS), liquid styrene butadiene rubber (LR) and maleated EVA (MAEVA), respectively. APS and MAEVA were found to be the most and least favourable compatibilizer, respectively. Apart from functioning as reactive compatibilizer, APS also reclaimed the RTR phase further. These lead to improved dispersion of smaller RTR phase in EVA matrix and enhanced the interfacial adhesion. Electron beam irradiation revealed the presence of radical stabilizing and scavenging additives within RTR which retards the crosslinking process in RTR and RTR/EVA blends. Though chain scissions were predominant; study showed the replacement of S-S and S-C bonds with stronger and stiffer C-C bonds ensures the retention of RTR and RTR/EVA blends properties upon irradiation. Compatibilization of RTR/EVA blend by APS (50RTR/5APS) also improved the crosslinking efficiency. However, the blend still suffered from oxidative degradation from irradiation in air. Radiation sensitizers, trimethylol propane triacrylate (TMPTA), tripropylene glycol diacrylate (TPGDA) and N,N-1,3 Phenylene Bismaleimide (HVA2), were used to accelerate the irradiation induced crosslinking in RTR and 50RTR/5APS blends. Presence of radiation sensitizers leads to simultaneous improvement in toughness and tensile strength of RTR and 50RTR/5APS blends. Elastic capacity of RTR phase was restored and interfacial adhesion enhanced in the presence of radiation sensitizers.

Urban air quality has been a topic of major public concern and scientific research in recent years. Several theoretical and experimental studies have focused on the assessment of air quality within street canyons and other microenvironments (intersections, motorways, parking spaces, etc.), where population exposure to traffic-related pollutants is relatively high. The aim of this study was to develop a practical methodology for assessing traffic-related air pollution in urban streets, after testing available monitoring and modelling techniques. To meet this objective, a large amount of original air quality, meteorological and traffic data were collected during four intensive short-term and one long-term monitoring campaigns carried out in the region of Paris from December 1998 to December 2001. These campaigns covered three representative street canyon sites (Bd. Voltaire, Rue de Rennes, Av. Leclerc - PI. Basch) as well as a motorway service station (RN10 petrol station). Passive and active monitoring techniques were used to sample a wide range of inorganic (CO, NO X and Os) and organic gases (benzene, toluene, xylene, ethylbenzene, formaldehyde, acetaldehyde, etc.) at different heights and distances from the kerb. Indicative background measurements were also taken during the same sampling periods. Furthermore, relevant meteorological (synoptic and local) and traffic information was obtained on each site. The analysis of the data gave insights into the dispersion and transformation processes taking place within the streets. Channelling effects induced by parallel to the road axis winds gave rise to relatively high kerbside pollution levels. On the other hand, perpendicular synoptic winds generated air vortices within the canyons, which resulted in steep crossroad concentration gradients. In that case, higher pollution levels were observed on the leeward than on the windward side of the streets. A significant reduction of concentrations with height above the ground was also observed within two of the street canyons (Bd. Voltaire and Av. Leclerc). In all cases, roadside concentrations were several times higher than the corresponding urban background values. This spatial variability indicates a strong transport effect on the pollutant distribution within urban canyons, caused by the synoptic wind and influenced by the geometry of the street. That may have serious implications in terms of population exposure and compliance with air quality legislation. In this context, the siting of permanent monitoring equipment becomes crucial. A relationship between CO and benzene as well as an exponential expression linking pollutant concentrations at different heights within the canyons were empirically deduced. Five dispersion models of different levels of complexity (STREET-SRI, OSPM, AEOLIUS, CAR-International, and CALINE4) were used to calculate CO and benzene concentrations at the campaign sites. The Computational Fluid Dynamic code PHOENICS was also tested for one location. The comparison between observed and predicted values revealed the advantages and drawbacks of each model in association with the configuration of the street and the meteorological conditions. Furthermore, a sensitivity and uncertainty analysis involving three of the available models (STREET-SRI, OSPM and AEOLIUS) was carried out. OSPM was slightly modified in order to allow user access to certain internally coded parameters. An operational method combining multi-site sampling and dispersion modelling was finally proposed for assessing air quality in urban streets, taking into account the pronounced spatial and temporal variability of traffic-related air pollution, the modelling uncertainty, the practical constraints related to measurements and models, and the needs of decision makers. This methodology may find wider application in air quality management, urban and transport planning, and population exposure studies.

Phytoremediation is a green technique used to restore polluted sites through plant-initiated biochemical processes. Its effectiveness, however, depends on the successful establishment of plants in the contaminated soil. Soils that are contaminated with polycyclic aromatic hydrocarbons (PAHs), especially low molecular weight, mobile PAHs such as naphthalene pose a significant challenge to this. Plant roots growing in these soils exhibit changes to their structure, physiology and growth patterns. Tall fescue (Festuca arundinacea) roots grown in sand contaminated with either petroleum crude oil (10.8g total extractable hydrocarbons kg-1 sand dw) or naphthalene (0.8g kg-1 sand dw) exhibited a temporary inhibition in elongation with accelerated lateral growth (p<0.01), whilst also showing a deviation from the normal root orientation responses to gravity. Scanning electron micrographs (SEM) revealed that the stele in the contaminated roots was located much further away from the root epidermis, because the cortex was larger (p<0.001) due to the cells being more isodiametric in shape. Once past the initial acclimatisation period of 2.5-3.0 months, no visual differences were observed between control and treated plants, but the root ultrastructural modifications persisted. The fluorescent hydrophobic probe „Nile red‟ was applied to the epidermis of a living root to mimic and visualise the uptake of naphthalene into the root through the transpiration stream. The root sections were also stained with 0.1% (w/v) berberine hemisulphate in order to stain Casparian bands. Overlaying images obtained with the use of Texas red HYQ filter (wavelength 589-615nm) and UV illumination (wavelength 345-458nm) revealed the presence of passage cells in the endodermis and uptake of Nile red into protoxylem vessels beyond the endodermis of control roots. On the other hand, the path of Nile red was blocked at the endodermis of naphthalene- treated roots. The cell walls in the endodermis of naphthalene-treated roots were prominently thickened (p<0.001) and lacked passage cells. The treated roots also possessed a well-formed exodermis (p<0.01). The results suggest that the well-formed endodermis lacking passage cells, the well-formed exodermis as well as the increased cortex zone provided an effective barrier to the flux of hydrophobic xenobiotics towards the inner core of the roots, if previously exposed to the contaminants. The SEM images of naphthalene-treated as well as crude oil-treated roots showed partial collapse in the cortex zone, presumably due to water stress, but the treated plants withstood drought stress better than the control plants. The underlying physiological changes responsible for the adaptive responses of tall fescue to the exposure to naphthalene contamination were studied through metabolic profiling of plant roots and shoots. The results indicated synergistic interactions between sugars or sugar- like compounds and phenolic compounds may assist to create an integrated redox system and contribute to stress tolerance in naphthalene-treated tall fescue. The signal for a compound speculated to be indole acetic acid (IAA) was either subdued or absent in the tissues of naphthalene-treated tall fescue, suggesting the existence of a detoxification mechanism/ defence pathway in the treated plants. The ultra-structural and molecular modifications, resulting from PAH stress enabled tall fescue to resist tougher challenges.

The key controlling factor in the effective energy conversion of coal to combustible gases during the UCG process is the behaviour of the pyrolysed char in the reduction zone of the UCG cavity, which has not been published in available academic literature. This study investigates the impact of the operating parameters during the reduction zone of UCG using a bespoke high pressure high temperature rig which was developed as part of this research work. This rig, operating at temperatures of up to 900 oC and at pressures up to 5.0 MPa, simulates the UCG process including each UCG zone individually for a broad range of underground conditions to a depth of 500 m. Carbon dioxide and steam were used as the primary reductants with char derived from dry steam coal and anthracite sample. Carbon dioxide and steam were injected at a variety of pressures and temperatures, plus at a range of relative H2O/CO2 proportions. The composition of the resulting product gas of both coals was measured and subsequently used to calculate carbon conversion (X), carbon conversion of combustible gases ( ), cold gas efficiency (CGE) and low heating value (LHV) of the product gas. Optimal operating conditions were determined for the dry steam coal and anthracite that produced the best gas composition both at atmospheric and elevated pressure and are unique for each UCG system. A shrinking core model was employed to describe the behaviour of the pyrolised char to determine the activation energy and pre-exponential factor at atmospheric pressure for both coals. The evolution of the volatile matter of both coals and its contribution to the overall UCG performance was also determined. An optimum H2O/CO2 ratio was determined for both coals which enhanced the gasification rate of both coal chars up to the ratio of 2:1, above this ratio the effect saturated for both coals. It was shown that pressure increases the reduction-gasification process of the chars which suggests that there is an optimum operating pressure which produces a peak in carbon conversion, CGE and LHV for the product gas over the conditions tested that differs for each coal. Therefore UCG projects aiming at reaching higher pressures will not achieve an increase in the output, unless there are some new effects occurring above 4.0 MPa. Pressure enhances the gas solid reactions and almost doubles the max carbon conversion ( of combustible gases achieved at elevated pressure compared to that at atmospheric pressure. A shrinking core model was modified to take into account the effect of total pressure to the gasification rate of dry steam coal at 900 oC and pressures ranging from 0.7 to 1.65 MPa. Reaction constants for various pressures at 900 oC were determined for both coal chars. Analysis of data shown that typical UCG operations on low rank coals provides a combustible product gas that relies heavily on releasing the volatile matter from the coal and does not depend on the carbon conversion of char to gas which justifies the high CGE and LHV of the product gas found in the field trials. It was found that carbon conversion X is not significantly affected by the type of coal and that the carbon converted during UCG is between approximately 45% for high rank coals up to 55% for low rank coals. Experimental results were used to calculate the output, size and UCG model of a potential power plant which produced realistic solutions and proves that high rank coals can be suitable for UCG projects. Anthracite can produce almost the same amount of combustible gases as the dry steam coal operating under specific conditions but with a lower CGE and LHV which suggests that anthracite may be found to be more suitable for producing hydrocarbons with UCG than energy.

Dealing with municipal solid waste has become a problematic issue in the United Kingdom (UK). With actions to mitigate the potentially adverse impacts of climate change debate and space for, and costs of, landfill becoming critical, a landfilldominated strategy is no longer acceptable. In this context, the attitudes and behaviour of young adults, particularly university students, who often have little experience of taking responsibility for waste management activities, have not been studied in great detail. Since the 1960s, the UK higher education system has expanded six fold to >2.4 million students. The overall production of waste at Higher Education institutions (HEIs) is therefore very large and presents significant challenges as the associated legislative, economic and environmental pressures can be difficult to control and manage. Therefore, a comprehensive research focusing on university students is urgently required. Changing the way HEIs deal with their waste is an important issue because of fast-changing legislation and increasing costs. The solution is a new approach to waste management: a revolutionary change in the way that HEIs think, the way HEIs act and the way HEIs handle their waste. This has massive implications for the Higher Education (HE) sector. It means developing extensive institution-wide infrastructure to provide greater flexibility and user-centric solutions to suit the need of students and staff. It also means that HEIs work together and potential collaboration between HEIs and Local Authorities (LAs) to maximise resource efficiency, meet future legislative requirements and achieve their corporate responsibilities and commitments. This thesis reports on a study of waste management practices at HEIs in the UK. The issue was approached from both a theoretical and a practical standpoint. The study used the University of Southampton (UoS) as a case study and examined how waste recycling projects can be developed effectively using infrastructure, service provision and behavioural change techniques as part of a wider research programme investigating waste management in medium- and high-density housing. The study clearly showed that there was potential for significantly improving reuse and recycling at university halls of residence (HoR) and that more convenient and higher quality infrastructure and service provision resulted in higher recycling rates. Furthermore, students have lifestyles that impact significantly on waste arisings and consequently on waste management operations at HoR (and probably at HEIs and student-dominated residential areas). For schemes to be successful at HEIs, they must be based on a thorough understanding of students’ recycling behaviour, and their perceptions of the barriers to recycling. The key to unlocking behaviour change lies in the provision of appropriate infrastructure and effective service provision alongside a targeted behaviour change programme. Mass media coverage especially the Internet has a rising influence on university students’ environmental knowledge while environmental education at school has become the secondary source of information. The results also revealed that university students possessed less knowledge than they believed which makes informative behavioural interventions a vital component of effective recycling schemes at HEIs

The role of voids in composite failures has not been well understood or been characterized. This study presents the result of an investigation aimed at examining the mechanical behaviour of unidirectional carbon fibre-reinforced polymer matrix materials as used by the wind turbine industry. The experimental program investigates the effect of the void content, different manufacturing methods, type of loading (the three-point bending vs. the four-point bending) on the static strength and fatigue life under a flexural load. The four ply unidirectional carbon/epoxy composites were manufactured using the SPRINT and prepreg manufacturing methods. Manufacturing by these methods has successfully produced the composite materials with varied void contents and the voids are found to concentrate primarily in the area where the adjacent plies meet. The SPRINT materials contain voids in the range of 1.63- 2.89% while the prepreg laminates have an average void content of 3.6% for the debaulked laminates and 6.8% for the non-debaulked laminates. The voids in the SPRINT laminate are small and they are distributed inhomogeneously. The majority of the voids are less than 0.04 mm2 in size with a shape between a circle and an ellipse. The three point bending tests show that the flexural strength exponentially decrease as much as 6.4% for the SPRINT and 6% for the prepreg for every 1% increase of the void content. The similar void effect for both materials may be due to their similar microstructures. There is a similar effect on the increase in the void content for the flexural strength and the flexural fatigue sensitivity for both the three and four point bending tests. This means that the voids do not play any large role in the three-point bending as compared to the four point bending. The mechanism of failure is observed using the optical microscopy and the X-ray tomography of the polished edge and cross section of the area near the failure. The voids are found to interact with the cracks in both the static and fatigue failures. The image of the cross section near the failure area of the static test samples seem to suggest that the voids coalesce to each other under loading. By using the acoustic emission, it can be confirmed that a major failure occurs due to the fibre breakage. In addition, the acoustic emission results also show that the failure behaviour of the low and high void content specimens is significantly different.