The objective of the research is to develop a user friendly framework for an internet GIS (Geographic Information Systems) application. The study aims at providing a map with GIS capabilities without requiring the clients (users of the website) having to install ArcGIS (a product of ESRI) software on their personal computers along with the facility to download hydrological data. It also aims at providing a methodology to synthesize data in case of data gaps. High resolution data was collected in a small watershed in west Central Florida to measure hydrologic storages and fluxes during 2001-2004. Meteorological, surface and groundwater data were collected at 5 to 10 minute intervals. A watershed database was constructed using Microsoft Access and was normalized to 3NF (third Normalization Form) for easy update. The databases available do not involve user-friendly tools to map data collection locations or to facilitate interactive delivery of data. In many fields like hydrology, it is important to provide spatial location of the data points with the data. In addition there is also a need for one platform wherein various user communities (students, planners, hydrologists etc) can be served. Thus there is a need for an online user-friendly environment, which allows for interactive delivery of data along with mapping and spatial analysis. To address this need an ArcIMS website was constructed. It includes ortho-photography of the site, which can be overlaid with the shapefile of the data locations thus giving the user reference orientation of the data locations. The user is allowed to download data in the form of text files based on the required temporal resolution and date ranges. Furthermore, users are provided with valuable data sets to parameterize or test hydrologic models applied to west-central Florida conditions. The website has a feature to generate synthetic data using linear correlation in cases where data are unavailable for the requested period of time. The website also serves the dual role of providing accessible surface and groundwater information to the public. It can also be used as a desktop geographic work tool for engineers, planners and developers, to help better understand the surface water, vadose zone and groundwater interaction. Hence this website is useful not only for professional hydrologists but also for graduate research.

The purpose of this dissertation is to — on occasion very literally — shine a light on processes that occur in non-thermal plasmas containing CO2, mostly for CO2 conversion. In particular, the focus lies on the transient behaviour of these discharges: how do these systems evolve over time before they settle in a (non-thermal) equilibrium. In addition to that, it analyses trends in the field of plasma-catalytic CO2 conversion as a whole to evaluate the current state-of-the-art, but also presents a new platform for the community to contribute and collaborate on, to facilitate cross-comparison between disparate experiments. The first part consists of experiments performed on: (a) an atmospheric pressure nanosecond repetitively pulsed (NRP) discharge for CO2 conversion, and (b) a test bed system for a remote CCP plasma source for plasma-enhanced atomic layer deposition (PE-ALD) of trimethylaluminium (TMA). The common theme in these experiments is a focus on the application of time-resolved, in situ diagnostics to study transient behaviour in the systems under investigation. The main diagnostics employed for such measurements are optical emission spectroscopy (OES) and laser induced fluorescence (LIF), which can provide complementary results when used in conjunction. In particular, this work presents the following results: A study of the evolution of emission from an NRP discharge (using OES), establishing both electron densities (by Stark broadening of atomic oxygen and carbon lines) and gas temperatures (by the N2 second positive system) as the discharge evolves from a breakdown phase to a spark phase. It furthermore explores the changes to these properties when operating in burst mode, where a subsequent pulse experiences a memory effect from the preceding one, which has been shown to be conducive to efficient conversion in literature. A study into the effect on energy efficiency of CO2 conversion by alternating the power modulation in an NRP discharge. Crucially, using CET-LIF (collisional energy transfer LIF) and OES it is shown that while power deposition to the discharge occurs in the order of 100 ns in the discharge, CO2 dissociation occurs on a timescale beyond a microsecond. This indicates that instead of direct electron impact, molecular-excitation kinetics play an important role under these conditions for CO2 dissociation. By shortening the time between pulses in a burst (down to 33 us in the work), these mechanisms can be further enhanced, by prolonging the quasi-‘metastable’ state of the system. The application of LIF in a PE-ALD process plasma along with OES, where diffusion profiles were measured close to the substrate surface with local time-resolved measurements of the OH ground state density. These indicate that the investigated surface reactions finish on a timescale of 100 ms, faster than would be indicated by OES which effectively measures emission from the bulk plasma after diffusion of reaction products away from the surface. The second part of this work is an open access database on plasma(-catalytic) CO2 conversion that is instrumental in identifying and verifying trends in experimental data, but also stresses the importance of rigorous reporting of essential parameters in literature. The approach in literature is diverse: some studies focus more on a mechanistic understanding of the fundamental processes, whilst others already focus on process tailoring and optimization for industrial applications. Trends observed in earlier review papers are observed as well and can now be trivially reproduced. The database platform (https://db.co2pioneer.eu) is put forward as a new tool for the community to easily cross-compare and contextualize experimental outcomes and strongly encourages new contributions. Based on the 196 papers included at the time of publication, a number of observations and recommendations can already be made. Chief among those is a clear and present need in the field for a more fundamental understanding of plasma-catalysis interaction, to develop techniques and criteria that are properly suited to test the synergy of both, rather than relying on methods from e.g. traditional thermal-catalysis. Also in this instance, local, time-resolved diagnostics may play a key role, but their implementation will be challenging.