The forgotten role of the ground state in atmospheric photochemistry. This project aims to provide novel solutions to two deficiencies in current atmospheric chemistry models. That is, molecular hydrogen (H2) is underestimated by up to a factor of two, and in polluted areas, HO2 concentrations are underestimated by up to a factor of ten. The project will investigate these solutions and assess their local and global atmospheric impact. By better characterising the atmospheric H2 budget, and the r ....The forgotten role of the ground state in atmospheric photochemistry. This project aims to provide novel solutions to two deficiencies in current atmospheric chemistry models. That is, molecular hydrogen (H2) is underestimated by up to a factor of two, and in polluted areas, HO2 concentrations are underestimated by up to a factor of ten. The project will investigate these solutions and assess their local and global atmospheric impact. By better characterising the atmospheric H2 budget, and the role of ground state reactions in general, the predictive ability of atmospheric models will be improved. This will allow, for example, the outcomes of any change in atmospheric H2 concentration, potentially as part of any future hydrogen economy, to be predicted before they occur. The benefits of this project are global: they allow us to better predict the impact of changes to atmospheric composition – before they occur, and local: Australia’s strengths in physical, theoretical and atmospheric chemistry are reinforced.Read moreRead less
Reactive Intermediates in Atmospheric and Combustion Chemistry. Reactive intermediates are the key species that determine outcomes of the chemical reaction networks in atmospheric and combustion chemistry. However, most reactive intermediates remain undiscovered. The project aims to discover these intermediates using laser spectroscopy. Current models of atmospheric chemistry cannot account for the carbon balance over forests, nor the formation of secondary organic aerosols. Combustion models st ....Reactive Intermediates in Atmospheric and Combustion Chemistry. Reactive intermediates are the key species that determine outcomes of the chemical reaction networks in atmospheric and combustion chemistry. However, most reactive intermediates remain undiscovered. The project aims to discover these intermediates using laser spectroscopy. Current models of atmospheric chemistry cannot account for the carbon balance over forests, nor the formation of secondary organic aerosols. Combustion models struggle to predict how next-generation fuels burn in modern engines. The successful discovery of these intermediates would allow models to be more accurate and predictive. This will allow scientists, engineers and policy makers to make more informed decisions about atmospheric processes and design more efficient new fuels.Read moreRead less
Formation, photochemistry and fate of gas-phase peroxyl radicals. This project aims to understand how peroxyl radical reactions modulate the composition of air. The gas-phase chemical reactions of organic peroxyl radicals contribute to air quality in clean and polluted environments. However, experimental observations of these reaction intermediates and the complex mechanisms governing their formation and fate are limited. This project will use mass spectrometry and laser-based methods to interro ....Formation, photochemistry and fate of gas-phase peroxyl radicals. This project aims to understand how peroxyl radical reactions modulate the composition of air. The gas-phase chemical reactions of organic peroxyl radicals contribute to air quality in clean and polluted environments. However, experimental observations of these reaction intermediates and the complex mechanisms governing their formation and fate are limited. This project will use mass spectrometry and laser-based methods to interrogate the chemical and photochemical reactions of peroxyl radicals in the gas phase. This project expects to understand the composition and dynamics of the troposphere and inform strategies to improve air quality.Read moreRead less
Chemistry at the threshold: unusual mechanisms and unexpected products. The chemical processes in combustion and in the atmosphere are complex and understood incompletely; for example 30-60 million tonnes of acids in the atmosphere are unaccounted for. The project will measure and model three new chemical processes that may account for the atmospheric acids, and other unexplained occurrences in combustion chemistry.
Atmospheric photochemistry - it's a lot more complicated than we thought. The project plans to develop a more accurate model of the changing atmosphere. The chemical composition of Earth’s atmosphere is changing because of anthropogenic activities. Predicting the consequences of this change requires accurate chemical models. The hydroxyl radical (OH) is the most important radical in the atmosphere, yet atmospheric models predict its concentration in forested regions to be about 10 times lower th ....Atmospheric photochemistry - it's a lot more complicated than we thought. The project plans to develop a more accurate model of the changing atmosphere. The chemical composition of Earth’s atmosphere is changing because of anthropogenic activities. Predicting the consequences of this change requires accurate chemical models. The hydroxyl radical (OH) is the most important radical in the atmosphere, yet atmospheric models predict its concentration in forested regions to be about 10 times lower than measured. These models also predict the amount of organic acids to be lower than measured. This project hypothesises two new chemical processes to account for these discrepancies. Photo-isomerisation of carbonyls to enols is suggested to be a source of organic acids. Reaction of extraordinarily hot carbonyl photofragments with oxygen is hypothesised to be an important source of OH radicals.Read moreRead less
A molecular understanding of transport fuels to drive clean and efficient combustion. A molecular understanding of hydrocarbon combustion remains incomplete and this inhibits the deployment of alternative fuels and clean/efficient engine technologies. This project will develop the chemistry that will enable accurate combustion models to accelerate developments towards clean and efficient fuels for the twenty-first century.
Molecular signatures of complex photodissociation reactions. All energy on earth comes from the sun, either directly (e.g photosynthesis) or indirectly (e.g fossil fuels). Photochemistry is the study of how this light is absorbed and what happens to a molecule afterwards. Despite significant experimental and theoretical advances in the past decade (some in our lab), scientists still cannot predict the outcomes of most photochemical reactions. In this project we will determine the reactivity o ....Molecular signatures of complex photodissociation reactions. All energy on earth comes from the sun, either directly (e.g photosynthesis) or indirectly (e.g fossil fuels). Photochemistry is the study of how this light is absorbed and what happens to a molecule afterwards. Despite significant experimental and theoretical advances in the past decade (some in our lab), scientists still cannot predict the outcomes of most photochemical reactions. In this project we will determine the reactivity of several small, fundamental organic molecules. Not only are these molecules pollutants around our cities, but discovery of how they react in the presence of light will allow us to understand and predict the photochemistry of a much wider range of organic species.Read moreRead less
Helium droplets: a nanoscale laboratory for studying intermolecular bonding and chemical reactivity. This type of research requires a rather complicated apparatus capable of creating a stream of helium droplets, embedding molecules and interrogating their properties using laser spectroscopy. The apparatus built in Sydney is the only one capable of this in Australia and using this new apparatus we will create many novel, bizarre and intriguing aggregates of molecules and atoms. The project involv ....Helium droplets: a nanoscale laboratory for studying intermolecular bonding and chemical reactivity. This type of research requires a rather complicated apparatus capable of creating a stream of helium droplets, embedding molecules and interrogating their properties using laser spectroscopy. The apparatus built in Sydney is the only one capable of this in Australia and using this new apparatus we will create many novel, bizarre and intriguing aggregates of molecules and atoms. The project involves cutting-edge scientific methods and will shift the boundaries of can-do science in the laser laboratory at the University of Sydney and in Australia in general.Read moreRead less
The dynamics of turbulent entrainment in sheared convective boundary layers. This project aims to develop general laws to enable the accurate prediction of boundary layer entrainment processes. This will be significant in a wide range of environmental and engineering applications. In particular, the current lack of understanding of this area is a major source of uncertainty in the latest generation of global climate models.
Links between bushfires in Victoria and floods in Queensland. This project will investigate connections between bushfires in Victoria and floods in Queensland under the framework that atmospheric blocking can be thought of as a common link. High resolution runs using the Intergovernmental Panel on Climate Change future projections of the energetics of high impact weather will improve climate forecasts in sensitive coastal areas of the country.