Diffusion and Equilibration in Viscous Atmospheric Aerosol
Lead Research Organisation:
University of Bristol
Department Name: Chemistry
Abstract
Aerosols are a key component of the atmosphere. Defined as either solid particles or liquid droplets dispersed in the gas phase, aerosols can scatter and absorb sunlight and terrestrial infrared radiation influencing the radiation budget and
having a direct effect on climate. They also act as nuclei on which water can condense, leading to the formation of cloud droplets, indirectly influencing the climate. As well as having many natural sources, they can form in polluted environments from the condensation of semi-volatile organic compounds forming secondary organic aerosol (SOA). The composition of SOA is rich in oxidised organic compounds and can contain organic molecules of high molecular weight. When the atmosphere is dry or cold, SOA particles can be highly viscous; indeed, it has been shown that SOA can exist as glassy particles. As such, droplets formed from water or formed from highly viscous SOA can differ in their viscosity by more than 15 orders of magnitude.
Aerosol droplets that are largely water (eg. cloud droplets) have low viscosity, flow readily, and deform and spread when deposited. When exposed to changes in relative humidity and temperature, they can respond quickly to the change in the environment, losing or gaining water and also any semi-volatile or volatile organic compounds. They are, in essence, at equilibrium in composition with the surrounding gas phase. For particles approaching the glass transition, the particles do not deform and have the mechanical properties of a solid. They can only respond slowly to changes in the environment, losing or gaining water, semivolatile and volatile organic components only very slowly. Indeed, it can be estimated that such particles could in principle take many days to equilibrate and suggesting that SOA can exist in a kinetically arrested/hindered state in the atmosphere. Predicting the properties and impacts of aerosol in the atmosphere relies on knowing if the aerosol mass is in thermodynamic equilibrium or if it is kinetically limited, with significant consequences for understanding even the mass of aerosol in the atmosphere and the ability of the aerosol to form liquid cloud droplets or ice crystals.
In this project, we will use a combination of single particle measurements, models and simulations to characterise the viscosity of ambient particles and the diffusion kinetics of water and organic components within viscous aerosol.
Measurements will be made using individual particles captured in aerosol optical tweezers or in an electrodynamic balance. Light scattering measurements that allow the accurate determination of droplet size and refractive index will be used to examine the response of the particle to changes in environmental conditions. From the time-dependence of these changes, the diffusion of molecules within the particle can be determined. The viscosity can be measured directly by coalescing two particles and determining the timescale for the shape of the composite particle to relax to a sphere. Measurements of particles of simple and complex composition will be used to refine models of aerosol viscosity and molecular diffusion constants.
In a final stage, the refined models will be used to assess the properties of viscous aerosol in the atmosphere. Initially, the role of viscous aerosol will be evaluated in a detailed model of the processes occurring in aerosol chamber measurements designed to simulate atmospheric aerosol. This will allow an assessment of the accuracy with which non-equilibrium kinetically limited aerosol processes can be captured and how sensitive the chamber measurements are to non-equilibrium effects. Finally, the sensitivity of atmospheric aerosol to non-equilibrium effects will be investigated using a wider scale regional model.
In summary, we will seek to better define when aerosol can be considered to be at equilibrium and when kinetically limited in the atmosphere.
having a direct effect on climate. They also act as nuclei on which water can condense, leading to the formation of cloud droplets, indirectly influencing the climate. As well as having many natural sources, they can form in polluted environments from the condensation of semi-volatile organic compounds forming secondary organic aerosol (SOA). The composition of SOA is rich in oxidised organic compounds and can contain organic molecules of high molecular weight. When the atmosphere is dry or cold, SOA particles can be highly viscous; indeed, it has been shown that SOA can exist as glassy particles. As such, droplets formed from water or formed from highly viscous SOA can differ in their viscosity by more than 15 orders of magnitude.
Aerosol droplets that are largely water (eg. cloud droplets) have low viscosity, flow readily, and deform and spread when deposited. When exposed to changes in relative humidity and temperature, they can respond quickly to the change in the environment, losing or gaining water and also any semi-volatile or volatile organic compounds. They are, in essence, at equilibrium in composition with the surrounding gas phase. For particles approaching the glass transition, the particles do not deform and have the mechanical properties of a solid. They can only respond slowly to changes in the environment, losing or gaining water, semivolatile and volatile organic components only very slowly. Indeed, it can be estimated that such particles could in principle take many days to equilibrate and suggesting that SOA can exist in a kinetically arrested/hindered state in the atmosphere. Predicting the properties and impacts of aerosol in the atmosphere relies on knowing if the aerosol mass is in thermodynamic equilibrium or if it is kinetically limited, with significant consequences for understanding even the mass of aerosol in the atmosphere and the ability of the aerosol to form liquid cloud droplets or ice crystals.
In this project, we will use a combination of single particle measurements, models and simulations to characterise the viscosity of ambient particles and the diffusion kinetics of water and organic components within viscous aerosol.
Measurements will be made using individual particles captured in aerosol optical tweezers or in an electrodynamic balance. Light scattering measurements that allow the accurate determination of droplet size and refractive index will be used to examine the response of the particle to changes in environmental conditions. From the time-dependence of these changes, the diffusion of molecules within the particle can be determined. The viscosity can be measured directly by coalescing two particles and determining the timescale for the shape of the composite particle to relax to a sphere. Measurements of particles of simple and complex composition will be used to refine models of aerosol viscosity and molecular diffusion constants.
In a final stage, the refined models will be used to assess the properties of viscous aerosol in the atmosphere. Initially, the role of viscous aerosol will be evaluated in a detailed model of the processes occurring in aerosol chamber measurements designed to simulate atmospheric aerosol. This will allow an assessment of the accuracy with which non-equilibrium kinetically limited aerosol processes can be captured and how sensitive the chamber measurements are to non-equilibrium effects. Finally, the sensitivity of atmospheric aerosol to non-equilibrium effects will be investigated using a wider scale regional model.
In summary, we will seek to better define when aerosol can be considered to be at equilibrium and when kinetically limited in the atmosphere.
Planned Impact
The specific impact of improving our understanding of the role of kinetic factors in governing the properties of atmospheric aerosol will largely benefit academic researchers working in atmospheric science, with an immediate tier being researchers requiring knowledge of the microphysical processes occurring in aerosol, as described under Academic Beneficiaries. Web-based tools will be extended to allow users to calculate the viscosity and diffusion constants of molecules in viscous aerosol and these will find immediate use by, for example, the project partners who will use them in microphysical kinetic models (Shiraiwa, MPI-Mainz,Germany) and to interpret analytical measurements (eg. particle bounce, Virtanen). The development of a kinetic framework within the Manchester Chamber Model (MANIC) will also lead to improvements in the interpretation of historical aerosol chamber measurements and future campaigns. Wider impact could result from the adoption of the model framework by a wider range of chamber instruments, benefiting from the involvement of two of the PIs in projects such as EUROCHAMP3.
The primary non-academic end-users of the proposed programme output in the UK would be the Met Office via existing links with the UKCA Climate-Chemistry-Community-Aerosol model, a joint NCAS-Met Office programme funded by NCAS,
GMR and DEFRA. The impacts of aerosol on climate are still credited with the largest uncertainty in climate forcing and a large part of the radiatively active boundary layer sub-micron aerosol burden is organic. Policy decisions with respect to quantification and mitigation of the climate impacts of aerosol require policy-related model simulations with at least a rudimentary but physically-based representation of organic aerosol. Prior to the proposed work, such model descriptions that include kinetic factors in regulating aerosol composition are unavailable and our study of the properties dictating gas/particle partitioning of organic compounds will be inform such a climate-focused goal. Other international non-academic agencies conducting IPCC simulations would be best placed to use the same reduced complexity secondary organic aerosol formalisms as supplied to the Met Office.
Many of the microphysical processes that will be studied have a significance than extends to academic beneficiaries beyond atmospheric science. The formation and properties of amorphous aerosol are important for large scale industrial processes such as spray drying in which microparticles are fabricated, often in amorphous states, through driving systems far from thermodynamic equilibrium and using the transport kinetics of volatile components to mediate physical transformations. Further, understanding water transport kinetics is important for better quantifying processes occurring during the delivery of drugs to the lungs and in the impact of environmental pollution on human morbidity and mortality.
Both viscosities and diffusion constants are fundamental quantities that are challenging to measure in supersaturated states and in the exotic compositional regimes in which aerosol exist. The measurements will provide a
broad catalogue of values for these properties and the refined models will provide a robust and versatile treatment over a wide range in conditions. Thus, they will find relevance in a broader range of chemical disciplines in which rheological and mass transport quantities are required.
Finally, air quality and climate change are important topics in the new 21st Century Science curriculum at GCSE and A level in the UK, and are of wider interest to the public. The impact from this project will be directly incorporated in the ongoing public engagement contributions made by the researchers leading this project.
The primary non-academic end-users of the proposed programme output in the UK would be the Met Office via existing links with the UKCA Climate-Chemistry-Community-Aerosol model, a joint NCAS-Met Office programme funded by NCAS,
GMR and DEFRA. The impacts of aerosol on climate are still credited with the largest uncertainty in climate forcing and a large part of the radiatively active boundary layer sub-micron aerosol burden is organic. Policy decisions with respect to quantification and mitigation of the climate impacts of aerosol require policy-related model simulations with at least a rudimentary but physically-based representation of organic aerosol. Prior to the proposed work, such model descriptions that include kinetic factors in regulating aerosol composition are unavailable and our study of the properties dictating gas/particle partitioning of organic compounds will be inform such a climate-focused goal. Other international non-academic agencies conducting IPCC simulations would be best placed to use the same reduced complexity secondary organic aerosol formalisms as supplied to the Met Office.
Many of the microphysical processes that will be studied have a significance than extends to academic beneficiaries beyond atmospheric science. The formation and properties of amorphous aerosol are important for large scale industrial processes such as spray drying in which microparticles are fabricated, often in amorphous states, through driving systems far from thermodynamic equilibrium and using the transport kinetics of volatile components to mediate physical transformations. Further, understanding water transport kinetics is important for better quantifying processes occurring during the delivery of drugs to the lungs and in the impact of environmental pollution on human morbidity and mortality.
Both viscosities and diffusion constants are fundamental quantities that are challenging to measure in supersaturated states and in the exotic compositional regimes in which aerosol exist. The measurements will provide a
broad catalogue of values for these properties and the refined models will provide a robust and versatile treatment over a wide range in conditions. Thus, they will find relevance in a broader range of chemical disciplines in which rheological and mass transport quantities are required.
Finally, air quality and climate change are important topics in the new 21st Century Science curriculum at GCSE and A level in the UK, and are of wider interest to the public. The impact from this project will be directly incorporated in the ongoing public engagement contributions made by the researchers leading this project.
People |
ORCID iD |
Jonathan Reid (Principal Investigator) |
Publications
Cai C
(2015)
Slow water transport in MgSO 4 aerosol droplets at gel-forming relative humidities
in Physical Chemistry Chemical Physics
Chu Y
(2018)
Viscosity of erythritol and erythritol-water particles as a function of water activity: new results and an intercomparison of techniques for measuring the viscosity of particles
in Atmospheric Measurement Techniques
Evoy E
(2019)
Predictions of diffusion rates of large organic molecules in secondary organic aerosols using the Stokes-Einstein and fractional Stokes-Einstein relations
in Atmospheric Chemistry and Physics
Haddrell A
(2019)
Identifying time-dependent changes in the morphology of an individual aerosol particle from its light scattering pattern
in Aerosol Science and Technology
Ingram S
(2017)
Characterising the evaporation kinetics of water and semi-volatile organic compounds from viscous multicomponent organic aerosol particles.
in Physical chemistry chemical physics : PCCP
Lienhard D
(2015)
Viscous organic aerosol particles in the upper troposphere: diffusivity-controlled water uptake and ice nucleation?
in Atmospheric Chemistry and Physics
Marsh A
(2018)
Amorphous phase state diagrams and viscosity of ternary aqueous organic/organic and inorganic/organic mixtures.
in Physical chemistry chemical physics : PCCP
Marsh A
(2017)
Accurate representations of the physicochemical properties of atmospheric aerosols: when are laboratory measurements of value?
in Faraday discussions
Marsh A
(2019)
Complexity of Measuring and Representing the Hygroscopicity of Mixed Component Aerosol.
in The journal of physical chemistry. A
Marshall FH
(2018)
Influence of particle viscosity on mass transfer and heterogeneous ozonolysis kinetics in aqueous-sucrose-maleic acid aerosol.
in Physical chemistry chemical physics : PCCP
Marshall FH
(2016)
Diffusion and reactivity in ultraviscous aerosol and the correlation with particle viscosity.
in Chemical science
Pereira K
(2019)
A new aerosol flow reactor to study secondary organic aerosol
in Atmospheric Measurement Techniques
Pereira K
(2019)
Novel Aerosol Flow Reactor to Study Secondary Organic Aerosol
Price HC
(2015)
Water diffusion in atmospherically relevant a-pinene secondary organic material.
in Chemical science
Reid JP
(2018)
The viscosity of atmospherically relevant organic particles.
in Nature communications
Rickards AM
(2015)
Variabilities and uncertainties in characterising water transport kinetics in glassy and ultraviscous aerosol.
in Physical chemistry chemical physics : PCCP
Rovelli G
(2019)
Comparison of Approaches for Measuring and Predicting the Viscosity of Ternary Component Aerosol Particles.
in Analytical chemistry
Song YC
(2016)
Measurements and Predictions of Binary Component Aerosol Particle Viscosity.
in The journal of physical chemistry. A
Song YC
(2020)
Transient cavity dynamics and divergence from the Stokes-Einstein equation in organic aerosol.
in Chemical science
Tikkanen O
(2019)
Optimization of process models for determining volatility distribution and viscosity of organic aerosols from isothermal particle evaporation data
in Atmospheric Chemistry and Physics
Zhang Y
(2017)
A rapid scan vacuum FTIR method for determining diffusion coefficients in viscous and glassy aerosol particles.
in Physical chemistry chemical physics : PCCP
Description | The following key discoveries and developments are reported: (1) Measurements have been made of viscosities and diffusion constants for water in a range of organic aerosol surrogates designed to improve our understanding of atmospheric aerosol viscosity and phase. (2) We have established a comprehensive data base of diffusion constants and viscosities which has allowed us to test the applicability of the Stokes-Einstein equation than previously possible, important for assessing estimated timescales of atmospheric aerosol equilibration. (3) Following from (1 and 2), this work is now being prepared for publication. Much of the work has already appeared in published and has involved collaborations with researchers outside Bristol. |
Exploitation Route | Further measurements are underway and will be used in models of ambient air quality by collaborator Dr. David Topping (university of Manchester) |
Sectors | Environment |
Title | Characterising the Evaporation Kinetics of Water and Semi-Volatile Organic Compounds from Viscous Multicomponent Organic Aerosol Particles (PCCP 2017) |
Description | The physicochemical changes experienced by organic aerosol particles undergoing dehydration into the surrounding gas phase can be drastic, forcing rapid vitrification of the particle and suppressing internal diffusion. Until recently, experimental studies have concentrated on quantifying diffusional mixing of either water or non-volatile components, while relatively little attention has been paid to the role of semivolatile organic component (SVOC) diffusion and volatilisation in maintaining the equilibrium between the gas and particle phases. Here we present methods to simultaneously investigate diffusivities and volatilities in studies of evolving single ternary aerosol particle size and composition. Analysing particles of ternary composition must account for the multiple chemical species that volatilise in response to a step change in gas phase water activity. In addition, treatments of diffusion in multicomponent mixtures are necessary to represent evolving heterogeneities in particle composition. We find that the contributions to observed size behaviour from volatilisation of water and a SVOC can be decoupled and treated separately. Employing Fickian diffusion modelling, we extract the compositional dependence of the diffusion constant of water and compare the results to recently published parametrisations in binary aerosol particles. The treatment of ideality and activity in each case is discussed, with reference to use in multicomponent core shell models. Meanwhile, the evaporation of a SVOC into an unsaturated gas flow may be treated by Maxwell's equation, with slow diffusional transport manifesting as a suppression in the extracted vapour pressure. Appearing in Physical Chemistry Chemical Physics (2017). |
Type Of Material | Database/Collection of data |
Year Produced | 2017 |
Provided To Others? | Yes |
Title | Comparison of Approaches for Measuring and Predicting the Viscosity of Ternary Component Aerosol Particles |
Description | Measurements of the water activity-dependent viscosity of aerosol particles from two techniques are compared, specifically from the coalescence of two droplets in a Holographic Optical Tweezers (HOT) and poke-and-flow experiments on particles deposited onto a glass substrate. These new data are also compared with the fitting of Dimer Coagulation, Isolation and Coalescence (DCIC) measurements. The aerosol system considered in this work are ternary mixtures of sucrose-citric acid-water and sucrose-NaNO3-water, at varying solute mass ratios. Results from HOT and poke-and-flow are in excellent agreement over their overlapping range of applicability (~103-107 Pa s); fitted curves from DCIC data show variable agree-ment with the other two techniques because of the sensitivity of the applied modelling framework to the representation of water content in the particles. Further, two modelling approaches for the predictions of the water activity-dependent viscosi-ty of these ternary systems are evaluated. We show that it is possible to represent their viscosity with relatively simple mixing rules applied to the subcooled viscosity values of each component or to the viscosity of the corresponding binary mixtures. |
Type Of Material | Database/Collection of data |
Year Produced | 2019 |
Provided To Others? | Yes |
Title | Data from Identifying time-dependent changes in the morphology of an individual aerosol particle from their light scattering patterns (08-2019) |
Description | The physical, chemical, and biological properties of an aerosol droplet/particle are dependent on the morphology of the droplet/particle itself; for example, a liquid droplet will be processed by oxidants in the gas phase in a fundamentally different way than a solid particle. Additionally, given their small size, aerosol droplets may change phase over timescales in the order of milliseconds (e.g. deliquescence or crystallisation). Thus, ability to rapidly and easily estimate the morphology of a droplet/particle is critical, especially in the interpretation of complex aerosol processes such as spray drying and dissolution. To be reported here is a novel method that uses the forward scattered light (~32o < ? < ~58o) passed through a droplet to determine the droplet/particles morphology. The algorithm was developed through the qualitative analysis of over one million individual phase functions of various particle morphologies. The algorithm can differentiate between four different morphologies: homogeneous, core/shell, with inclusions, and non-spherical/inhomogeneous. The algorithm is applicable to droplets between ~5 to ~30 ?m in radius. The rate of phase analysis is dependent on the rate in which the light scatter can be collected, in the data presented here a particle's morphology is reported every 10 milliseconds. The accuracy of the phase identification with the algorithm proposed in this work is very high (>90%); its utility is strengthened by the high frequency of the collection of scattered light, which allows an individual droplet to be probed upwards of over 100 times per second. Although not absolute on every phase function analysis, when coupled with repetition and high throughput, the algorithm presented here can be a valuable tool to easily and readily determine particle morphology in dynamic aerosol systems. |
Type Of Material | Database/Collection of data |
Year Produced | 2019 |
Provided To Others? | Yes |
Title | Measurements and Predictions of Binary Component Aerosol Particle Viscosity (J Phys Chem A, 2016) |
Description | Organic aerosol particles are known to often absorb/desorb water continuously with change in gas phase relative humidity (RH) without crystallisation. Indeed, the prevalence of metastable ultraviscous liquid or amorphous phases in aerosol is well-established with solutes often far exceeding bulk phase solubility limits. Particles are expected to become increasingly viscous with drying, a consequence of the plasticising effect of water. We report here measurements of the variation in aerosol particle viscosity with RH (equal to condensed phase water activity) for a range of organic solutes including alcohols (diols to hexols), saccharides (mono-, di- and tri-) and carboxylic acids (di-, tri- and mixtures). Particle viscosities are measured over a wide range (10^-3 to 10^10 Pa s) using aerosol optical tweezers, inferring the viscosity from the timescale for a composite particle to relax to a perfect sphere following the coalescence of two particles. Aerosol measurements compare well with bulk phase studies (well-within an order of magnitude deviation at worst) over ranges of water activity accessible to both. Predictions of pure component viscosity from group contribution approaches combined with either non-ideal or ideal mixing reproduce the RH-dependent trends particularly well for the alcohol, di- and tri-carboxylic acid systems extending up to viscosities of 10^4 Pa s. By contrast, predictions over-estimate the viscosity by many orders of magnitude for the mono-, di-, and tri-saccharide systems, components for which the pure component sub-cooled melt viscosities are >>10^12 Pa s. When combined with a typical scheme for simulating the oxidation of a-pinene, a typical atmospheric pathway to secondary organic aerosol (SOA), these predictive tools suggest that the pure component viscosities are less than 10^6 Pa s for ~97% of the 50,000 chemical products included in the scheme. These component viscosities are consistent with the conclusion that the viscosity of a-pinene SOA is most likely in the range 10^5 to 10^8 Pa s. Potential improvements to the group contribution predictive tools for pure component viscosities are considered. |
Type Of Material | Database/Collection of data |
Year Produced | 2016 |
Provided To Others? | Yes |
Title | Transient Cavity Dynamics and Divergence from the Stokes-Einstein Equation in Organic Aerosol |
Description | The diffusion of small molecules through viscous matrices formed by large organic molecules is important across a range of domains, including pharmaceutical science, materials chemistry, and atmospheric science, impacting on, for example, the formation of amorphous and crystalline phases. Here we report significant breakdowns in the Stokes-Einstein (SE) equation from measurements of the diffusion of water (spanning 5 decades) and viscosity (spanning 12 decades) in saccharide aerosol droplets. Molecular dynamics simulations show water diffusion is not continuous, but proceeds by discrete hops between transient cavities that arise and dissipate as a result of dynamical fluctuations within the saccharide lattice. The ratio of transient cavity volume to solvent volume increases with size of molecules making up the lattice, increasing divergence from SE predictions. This improved mechanistic understanding of diffusion in viscous matrices explains, for example, why organic compounds equilibrate according to SE predictions and water equilibrates more rapidly in aerosols. |
Type Of Material | Database/Collection of data |
Year Produced | 2020 |
Provided To Others? | Yes |
URL | https://data.bris.ac.uk/data/dataset/kew7yuaymnif2m388cmpgbg16/ |
Description | American Chemical Society Fall conference 2017 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Talk at American Chemical Society Fall conference in environmental impacts of aerosol chemistry symposium |
Year(s) Of Engagement Activity | 2017 |
Description | Contributed talk by Allen Haddrell at the annual conference of the American Association of Aerosol Research |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Contributed talk |
Year(s) Of Engagement Activity | 2015 |
Description | Contributed to a programme on BBC4 airing on the history of DSTL and Porton Down, "Inside Porton Down". |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Allen Haddrell and Jonathan Reid contributed to a programme on BBC4 airing on Tuesday 28th June at 9pm 2016 on the history of DSTL and Porton Down, "Inside Porton Down" providing scientific consultation and a demonstration of the properties of aerosols. |
Year(s) Of Engagement Activity | 2016 |
URL | http://www.bbc.co.uk/news/magazine-36606510 |
Description | Gordon Research Conference on Molecular Interactions and Dynamics |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Gordon Research Conference on Molecular Interactions and Dynamics at Stonehill College, Mass, US. |
Year(s) Of Engagement Activity | 2018 |
Description | Invited talk at Pittcon on aerosol droplet spectroscopy |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Invited talk at Pittcon on aerosol droplet spectroscopy in Orlando, Florida, US |
Year(s) Of Engagement Activity | 2018 |
Description | Invited talk at XXIst Symposium on Atomic, Cluster and Surface Physics, Obergurgl, Austria, 2018 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Invited talk at XXIst Symposium on Atomic, Cluster and Surface Physics, Obergurgl, Austria, 2018 |
Year(s) Of Engagement Activity | 2018 |
Description | Pittcon Conference, Orlando, Florida |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Invited talk at the annual Pittcon Conference, Orlando, Florida, February 2018. |
Year(s) Of Engagement Activity | 2018 |
Description | Plenary talk at Drug Delivery to the Lungs conference |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Plenary talk to all attendees at the annual drug delivery to the lungs conference at the Edinburgh International Convention Centre |
Year(s) Of Engagement Activity | 2017 |
Description | Postgraduate course in aerosol science, Beijing Institute of Technology, China |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | A taught course I delivered as a visiting professor |
Year(s) Of Engagement Activity | 2015 |
Description | Presentation of paper and talk at Faraday Discussion on Chemistry of the Anthropocene |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Presentation of paper and talk at Royal Society of Chemistry Faraday Discussion on Chemistry of the Anthropocene at University of York |
Year(s) Of Engagement Activity | 2017 |
Description | Research talk at University of Alberta, California |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Research talk at University |
Year(s) Of Engagement Activity | 2016 |
Description | Research talk at international conference |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Talk at Workshop on Molecular Understanding of Atmospheric Aerosols, Chaminade, California |
Year(s) Of Engagement Activity | 2016 |
Description | Seminars at Universities of Manchester and Cambridge |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | Invited talks |
Year(s) Of Engagement Activity | 2015 |
Description | Talk at American Association of Aerosol Research Annual Conference |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Research talk at international conference |
Year(s) Of Engagement Activity | 2016 |
Description | Talk at American Association of Aerosol Research annual conference |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Talk at American Association of Aerosol Research annual conference on the properties of secondary organic aerosol by post doc on project, Grazia Rovelli |
Year(s) Of Engagement Activity | 2017 |
Description | Talk at CECAM workshop on Crystallisation |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | CECAM workshop in Lausanne on crystallisation and nucleation. |
Year(s) Of Engagement Activity | 2017 |
Description | Talk at European Aerosol Conference 2016 |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Research talk at international conference |
Year(s) Of Engagement Activity | 2016 |
Description | Talk at Future of Chemical Physics conference in Oxford |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Research talk at international conference |
Year(s) Of Engagement Activity | 2016 |
Description | Talk at Spring meeting of the American Chemical Society |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Research talk at international conference |
Year(s) Of Engagement Activity | 2016 |
Description | Talk at University of Warwick |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | Research talk at university |
Year(s) Of Engagement Activity | 2016 |
Description | Talk at Workshop Entitled "Towards a Molecular Understanding of Atmospheric Aerosols" in Cologne, Germany |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Talk at Workshop Entitled "Towards a Molecular Understanding of Atmospheric Aerosols" in Cologne, Germany. This was a workshop attended by ~100 participants (academics, students and researchers) working in the field of atmospheric aerosols. |
Year(s) Of Engagement Activity | 2018 |
Description | Talk at XXIst Symposium on Atomic, Cluster and Surface Physics |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Invited talk at XXIst Symposium on Atomic, Cluster and Surface Physics 2018, Obergurgl, Austria (2018). |
Year(s) Of Engagement Activity | 2018 |
Description | Talk to local interest group |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Talk about atmospheric science and climate change at public engagement event held by A Rocha UK at Little Dewchurch, Herefordshire |
Year(s) Of Engagement Activity | 2017 |