PhD projects-  Cohort 1: 2019

The Coalescence of Drying Droplets

Theme: Basic processes

The initial experiment proposed here will focus on the collisions of water–water droplets of ~ 30–80 μm radius. This novel size makes the proposed work relevant to the research of aerosols and their microphysical properties. A comparison can be made with existing collisional regime maps of water to determine whether droplet size, and the shift in the kinetic regime, influencesthe collisional outcome. This will be investigated using two microdroplet dispensersto collide droplets, imaged by a stroboscopic imaging technique. Following this, the effect of viscosity on the regime map can be determined using the same method, with varying concentrations of aqueous sucrose droplets.

Supervisors: Prof Jonathan Reid (Bristol) and Dr Rachael Miles (Bristol)

Determining the effects of airborne particulates on immune and barrier epithelial cell function

Theme: Aerosols and Health

Airborne pollution is a complex mixture of biological and chemical sources but their specific effects on immune function are relatively poorly understood. This exciting cross disciplinary project will define the components of pollutants and explore their impact on immune cells.

Supervisors: Prof. Sheena Cruickshank (Manchester) and Dr. Alberto Gambaruto (Bristol)

Investigating the charge states of ambient and indoor aerosols

Theme: Aerosol Technology

Conveying and generation of powders can lead to very high levels of charge on particles, affecting their transport agglomeration and ultimate removal from the environment. Through modelling and experiments this project seeks to optimize collection of particles in filtration processes accounting for and manipulating electrostatic charge.

Supervisors: Dr Marc Stettler (Imperial), Dr Adam Boies (Cambridge) and Prof. Jonathan Reid (Bristol)

Building flexible biological particle detection algorithms for traditional and emerging real-time instrumentation 

Theme: Measurement Techniques

Whilst the importance of biological particles in the environment, human health and as a potential security threat is known, development of robust detection technologies remains a challenge. This project will apply and evaluate a range of machine learning techniques to to convert multidimensional signatures from new and emerging detection techniques into distinct PBA types.

Supervisors: Dr David Topping (Manchester)  and Dr Chris Stopford (Hertfordshire)

Particle engineering approaches to control the interaction of medicinal aerosols with the lung environment following inhalation 

Theme: Aerosols and Health

This article focuses on the delivery of solid drug particles by dry powder inhalers and reviews some of the particle properties that may underpin aerosol dynamics in the humidity of the respiratory system. Furthermore, in response, a novel way to produce monodisperse model particles with distinct characteristics and properties using microfluidic crystallisation techniques is presented. 

Supervisors: Prof Darragh Murnane (Hertfordshire) and Prof Jonathan Reid (Bristol)

Inhalable nanomedicine for treatment of pulmonary tuberculosis 

Theme: Aerosols and Health

The rapid spread of multi drug-resistant tuberculosis (TB) is a major threat to global public health. According to WHO ~1.8 million people die every year of TB, with an estimated 9.8 million new infections per year, which is exacerbated due to the number of patients infected with HIV/AIDs. Treatment of TB is lengthy, with the development of drug resistant organisms due to incomplete or inappropriate treatment. We propose that many of the shortfalls of treatment of multidrug-resistant TB could be overcome by reducing the high toxicity and poor efficacy of injectable small molecule antibiotics drugs.  The aim of the PhD is to develop an aerosolised, inhalable nanomedicine that delivers first line anti-tuberculous drugs.

Supervisors: Prof Terry Tetley (Imperial) and Dr Alexandra Porter (Imperial)

Development of a packed bed reactor for carbon nanotube synthesis

Theme: Aerosol Technology

This proposal will address the issue of understanding the concentration of all species at which aerogel forms. The methods to analyse the distribution of nanoparticles within the reactor both axially and radially will be performed via aerosol collection techniques. Once the fundamental reaction kinetics and concentrations of the chemically relevant species are both known and understood, the reaction will be put into a higher reaction density reactor. The data from this study will be used for modelling aerosol dynamics within the reactor and coupled with computational fluid dynamics model.

Supervisors: Dr Adam Boies (Cambridge)

Aerosol-assisted chemical vapour deposition (AACVD) of inorganic functional materials

Theme: Aerosol Technology

This project will use aerosol assisted chemical vapour deposition (AA-CVD) to develop inorganic and hybrid semiconducting materials e.g. SnS, Sb2S3 and FeS2 by the in-situ decomposition of soluble molecular precursors. The project offers a combination of chemical synthesis and aerosol/materials characterisation.

Supervisors: Dr Andrew Johnson (Bath) and Dr Adam Boies (Cambridge)

Exploring the limits of detection for single nanoscale aerosol particles by light scattering, absorption, and luminescence 

Damage to jet engines by airborne particulates; Detection and mitigation

Improving the understanding of the gas/particle partitioning behaviour of organic aerosols in different environmental conditions 

Theme: Basic processes

Understanding the partitioning of molecular constituents between the gas and particle phases is central to the whole endeavour of aerosol science. This project applies ultra-sensitive techniques to investigate the volatilisation of low and semi-volatile components from aerosol particles, their response to humidity and temperature, and refining predictive tools crucial for understanding air quality.

Supervisors: Prof Jonathan Reid (Bristol) and Dr David Topping (Manchester)

Size, sources and transport of the seeds of ice in clouds 

Theme: Environmental Aerosols

Our knowledge of the special aerosol particles which trigger ice formation in clouds is extremely poor. This project will take some of the first ever measurements of ice nucleating particle size in order to better understand their transport.

Supervisors:  Prof Ben Murray (Leeds) and Prof Catherine Noakes (Leeds)

Extinction Cross Section Measurements for Single Aerosol Particles Confined to a Linear Electrodynamic Quadrupole Trap

Theme: Environmental Aerosols

The contribution of organic aerosol to the warming of the Earth’s atmosphere remains uncertain because particle composition and morphology affect the absorption of sunlight. Using a recently developed spectroscopic apparatus, this project will measure precise optical properties of single, trapped aerosol particles.

Supervisors: Prof Andrew Orr-Ewing (Bristol) and Dr Adam Squires (Bath)

Dynamic Surface Properties of Atmospheric Aerosol and Resulting Climate Impacts

Theme: Basic processes

The surface tension of atmospheric aerosols impacts their ability to serve as cloud droplet seeds and affect climate. This project will develop approaches to measure droplet surface tensions and better resolve dynamics at the particle surface, working closely with modellers.

Supervisors: Dr Bryan Bzdek (Bristol) and Dr Matthew Watson (Bristol)