Zoran Ristovski

• Professor
• Head of Department at Queensland University of Technology

The frequency of coral bleaching events increased during the past decade in the Great Barrier Reef due to climate change, and rising ocean temperatures. Recent work has demonstrated that enhancing local-scale cloud albedo can reduce the sea surface temperatures in this region. However, little research has been done on variations in the aerosol prop...

The impact that biogenic emissions have on aerosol-cloud interactions across the Southern Ocean is poorly quantified. Here we use satellite and ship observations during austral summer to study these interactions. We present observational evidence that biogenic aerosols increase cloud condensation nuclei and cloud droplet number concentrations over...

Physicochemical characterisation of airborne particles requires appropriate sampling and deposition methods. The TSI Nanometer Aerosol Sampler 3089 (TSI NAS) has predominantly been used as an electrostatic precipitator for depositing airborne particles, enabling subsequent offline characterisation through techniques such as electron microscopy. How...

Reactive oxygen species (ROS) play an important role in atmospheric pollution, and their detection is essential for assessing air quality and health risks. This study developed and validated a standardized methodology for using the BPEAnit probe in a specially designed particle-into-liquid sampler, the Particle Into Nitroxide Quencher (PINQ), to me...

Plain Language Summary Tropical cyclones are among the most destructive weather extremes. We selected a local TC originating in the South China Sea, which made its first landfall on an island rather than the mainland, providing a rare opportunity to research the atmospheric composition of complete landfall and the sea‐land transport. Results show t...

The chemical properties of aerosols in the atmosphere significantly influence their impact on the global climate forcing and human health. However, a real-time molecular-level characterisation of aerosols remains challenging due to the complex nature of their chemical composition. The current study constructed an instrumental system for the real-ti...

Background Air pollution, particularly from Diesel Exhaust Particles (DEP) and Wildfire Smoke (WFS), is increasingly recognised as a significant driver of neuroinflammation linked to brain diseases. However, the role of microglia in mediating these neuroinflammatory responses remains poorly understood. This study aimed to investigate the effects of...

The amplification effect of anthropogenic‐biogenic interactions on secondary organic aerosol (SOA) formation remains debated, particularly regarding the impact of anthropogenic emissions on biogenic SOA (BSOA) formation in forests near megacities. This study concurrently measured typical biogenic and anthropogenic SOA tracers during day and night a...

Technological advancements offer the opportunity for interventions to reduce and potentially even counteract the impacts of climate change. However, advancements that can facilitate the adaptation of human and natural ecosystems to climate change, and possibly lessen the intensity and damaging impacts of extreme weather events, come with social, te...

Physicochemical characterisation of airborne particles requires appropriate sampling and deposition methods. The TSI Nanometer Aerosol Sampler 3089 (TSI NAS) has predominantly been used as an electrostatic precipitator for depositing airborne particles, enabling subsequent offline characterization through techniques such as electron microscopy. How...

Engine idling is a significant contributor to vehicle emissions, however, it is often unaccounted for. Presented in this study is a comprehensive analysis of gaseous and particulate emissions during cold idle compared to hot idle operations. Fuels used in this study were B20 (20%) and B10 (10%) (%v/v) blends of di-octyl phthalate (a third-generatio...

Light-absorbing carbonaceous aerosols primarily comprise black carbon (BC) and brown carbon (BrC), and they play a key role in atmospheric radiative forcing and global climate. Here, we present the light absorption, potential sources, and health risks of BC and BrC during the prescribed burning season at an urban background site in Brisbane based o...

Real driving emissions (RDE) testing are gaining attention for monitoring and regulatory purposes because of providing more realistic emission and fuel consumption measurements compared to laboratory tests. This study aims to develop machine learning (ML) based emission and fuel consumption estimation models using real-driving measurement data. A l...

Aerosol acidity plays a crucial role in atmospheric physicochemical processes, climate change and human health, particularly in the formation of secondary organic aerosols (SOA). However, understanding the characteristics and driving factors of aerosol acidity in background mountains has been limited. In this study, we conducted intensive field mea...

The remoteness and extreme conditions of the Southern Ocean and Antarctic region have meant that observations in this region are rare, and typically restricted to summertime during research or resupply voyages. Observations of aerosols outside of the summer season are typically limited to long-term stations, such as Kennaook / Cape Grim (KCG; 40.7∘...

This study presents a comprehensive analysis of the engine performance parameters during different temperature-based operating conditions: cold, preheated and hot. Novel blends of Di-octyl Phthalate (DOP) and diesel were prepared by using 10 and 20% DOP (%v/v), named B10 and B20, respectively, and compared with ultra-low sulphur diesel (B00). The e...

Understanding the mechanisms which inactivate airborne viruses is a current challenge. The composition of human respiratory aerosol is poorly understood and needs to be adequately investigated for use in aerovirology studies. Here, the physicochemical properties of porcine respiratory fluid (PRF) from the trachea and lungs were investigated both in...

In numerous epidemiological studies, exposure to particulate matter (PM) has been associated with negative health outcomes. It has been established so far that the detrimental health effects of particles cannot be explained by a single parameter, such as particle mass, as the complexity of chemical composition and reactivity of particles are not al...

Cold-start is an inevitable part of the daily driving operation for most vehicles. Given that exergy analysis can evaluate the sources of losses qualitatively and quantitatively using the first and second laws of thermodynamics, this study investigated the impact of engine temperature on energy and exergy parameters during engine warm-up. Using a t...

Black carbon (BC) aerosols significantly contribute to radiative budgets globally, however their actual contributions remain poorly constrained in many under-sampled ocean regions. The tropical waters north of Australia are a part of the Indo-Pacific warm pool, regarded as a heat engine of global climate, and are in proximity to large terrestrial s...

The remoteness and extreme conditions of the Southern Ocean and Antarctic region have meant that observations in this region are rare, and typically restricted to summertime during research or resupply voyages. Observations of aerosols outside of the summer season are typically limited to long-term stations, such as Kennaook/Cape Grim (KCG, 40.7° S...

Presented in this article is a comprehensive analysis of combustion behaviour using Di-octyl Phthalate (DOP)-an oxygenated third-generation biofuel, blended with ultra-low sulphur diesel (D100) in proportions of 10 % (DOP10D90) and 20 % (DOP20D80) (%v/v). The experiments were conducted on a heavy-duty diesel engine during ambient, preheated and hot...

The impact of respiratory particle composition on the equilibrium morphology and phase is not well understood. Furthermore, the effects of these different phases and morphologies on the viability of viruses embedded within these particles are equally unknown. Physiologically relevant respiratory fluid analogues were constructed, and their hygroscop...

This study investigated the impact of driving style and traffic condition on emissions and fuel consumption using a selected range of real-world transient drive cycles, using both diesel and a diesel–biodiesel blend on a turbocharged diesel engine. Using 30 drivers, real-world measurements were performed with a Hyundai iLoad 2017 automatic diesel v...

The impact of respiratory particle composition on the equilibrium morphology and phase are not well understood. Furthermore, the effects of these different phases and morphologies on the viability of viruses embedded within these particles are equally unknown. Physiologically relevant respiratory fluid analogues were constructed, and their hygrosco...

The share of biofuels in the transportation sector is increasing. Previous studies revealed that the use of biofuels decreases the size of particles (which is linked to an increase in particulate toxicity). Current emission regulations do not consider small particles (sub-23 nm); however, there is a focus in future emissions regulations on small pa...

Light-duty diesel vehicles are a significant contributor to urban air pollution. This study aimed to investigate the variation in driving style and emissions based on traffic conditions, route features and route familiarity using 30 drivers. Driving styles were assessed using acceleration, relative positive acceleration and velocity × positive acce...

Exposure to gaseous and particulate matter (PM) emissions from engine combustion can result in severe human health risks. Although blending biodiesel-diesel fuel presents reduction in diesel engine emissions, mixing fuel with an oxidation catalyst with considerable oxygen storage capacity (OSC) characteristic might better reduce the harmful engine...

Coral reefs have been found to produce the sulfur compound dimethyl sulfide (DMS), a climatically relevant aerosol precursor predominantly associated with phytoplankton. Until recently, the role of coral-reef-derived DMS within the climate system had not been quantified. A study preceding the present work found that DMS produced by corals had negli...

Surrogate fuels for hydrothermal liquefaction (HTL) algae biocrude depicting its nitrogen (N) and sulphur (S) content were simulated in this study and tested in a multi-cylinder diesel engine. The influence of N and S presence in the fuel on its combustion behaviour and emissions profile was investigated. To our knowledge, N and S-containing fuels...

Presented in this study is an analysis of gaseous and particulate emissions for three selected fuels during cold, warm and hot engine operation; low sulphur neat diesel (D100), and 10 and 20% (% v/v) of dioctyl phthalate (DOP) blended with diesel. Experiments were conducted on a turbocharged common rail heavy-duty diesel engine over a custom-design...

Diesel particle emissions are a major environmental concern and understanding its oxidation mechanisms is essential for development of diesel particulate filters (DPF) regeneration strategy and the control of the secondary particle emissions produced during regeneration. This study used X-ray Photoemission Spectroscopy to examine the oxygen functio...

Abstract In the transportation sector, the share of biofuels such as biodiesel is increasing and it is known that such fuels significantly affect NOx emissions. In addition to NOx emission from diesel engines, which is a significant challenge to vehicle manufacturers in the most recent emissions regulation (Euro 6.2), this study investigates NO2 wh...

Coral reefs have been found to produce the sulfur compound dimethyl sulfide (DMS), a climatically relevant aerosol precursor predominantly associated with phytoplankton. Until recently, the role of coral reef-derived DMS within the climate system had not been quantified. A study preceding the present work found that DMS produced by corals had negli...

Diesel engine cold start is emerging as a critical topic of investigation. Of key importance is the impact the warm-up period has on particulate emissions. Presented in this work is a fundamental and comprehensive study on the impact of cold, warm, and hot start on particulate emissions over a custom quasi-steady-state drive cycle discretized by fr...

Background: The health effects of e-cigarettes in patients with pre-existing lung disease are unknown. The aim of this study was to investigate whether aerosols from a fourth-generation e-cigarette produces similar in-vitro cytotoxic, DNA damage and inflammatory effects on bronchial epithelial cells (BECs) from patients with COPD, as cigarette smo...

The airborne dynamics of respiratory droplets, and the transmission routes of pathogens embedded within them, are governed primarily by the diameter of the particles. These particles are composed of the fluid which lines the respiratory tract, and is primarily mucins and salts, which will interact with the atmosphere and evaporate to reach an equil...

The importance of the in-cylinder pressure transducer has been proven in revealing the information about combustion and exhaust pollution formation, as well as for its capability to classify knock. Due to their high price, they are not used commercially for engine health monitoring, which is of significant importance. Hence, this study will investi...

The present study focuses on the synthesis of novel catalytic nanoparticles and their effect on combustion, performance, and emission characteristics of a diesel engine. For this purpose, Mg cations were doped into a Fe3O4 lattice to form MgxFe(3-x)O4 (x = 0.25, 0.5, 0.75, and 1) using a solution combustion method. Comprehensive characterization st...

In this paper, a novel multiscale modelling method is proposed for transient computational fluid dynamics (CFD) simulations of the human airways. The developed method is the first attempt to incorporate spatial coupling and temporal coupling into transient human airway simulations, aiming to improve the flexibility and the efficiency of these simul...

NOx emissions from diesel engines are a concern from both environmental and health perspectives. Recently this attention has targeted cold-start emissions highlighting that emission after-treatment systems are not effective in this period. Using a 6-cylinder, turbocharged, common-rail diesel engine, the current research investigates NOx emissions d...

This study investigates the morphology and nanostructure of soot particles during cold-start and hot-start engine operation of a diesel engine using oxygenated fuels. The soot samples were analysed using transmission electron microscopy. The oxygen content in the fuel was varied between 0 to 12%. The results showed that the primary particles during...

Light-duty diesel vehicles contribute significantly to urban air pollution. Laboratory-based standard driving test cycles do not take into account external driving factors, which greatly impact the vehicle emissions compared to the real-world driving emission (RDE) measurements. This results in higher emission levels obtained by RDE tests, compared...

Atmospheric semi-volatile organic compounds (SVOCs) are complex in their chemical and toxicological characteristics with sources from both primary combustion emissions and secondary oxygenated aerosol formation processes. In this study, thermal desorption of PM2.5 in association with online measurement of reactive oxygen species (ROS) was carried o...

Featured Application An ANN model successfully helped in harmonizing inputs from several instruments of different grade (low cost radon and lab grade particulate matter monitors) and enabled predictions of small ions concentration of comparable quality to the lab grade Gerdien type instrument. Abstract In this work we explore the relationship betw...

A comprehensive analysis of combustion behaviour during cold, intermediately cold, warm and hot start stages of a diesel engine are presented. Experiments were conducted at 1500 rpm and 2000 rpm, and the discretisation of engine warm up into stages was facilitated by designing a custom drive cycle. Advanced injection timing, observed during the col...

Cloud–radiation interactions over the Southern Ocean are not well constrained in climate models, in part due to uncertainties in the sources, concentrations, and cloud-forming potential of aerosol in this region. To date, most studies in this region have reported measurements from fixed terrestrial stations or a limited set of instrumentation and o...

The aerosol-driven radiative effects on marine low-level cloud represent a large uncertainty in climate simulations, in particular over the Southern Ocean, which is also an important region for sea spray aerosol production. Observations of sea spray aerosol organic enrichment and the resulting impact on water uptake over the remote Southern Hemisph...

Improving oxygen storage capacity (OSC) of metal oxides by doping with metal cations can produce a catalyst with superior properties to improve engine performance and reduce emissions. In this study, Mg cations were incorporated into a ferric oxide lattice to form Mg0.25Fe2.75O4 via the solution combustion method. The structure, texture, morphology...

The International Agency of Research on Cancer identifies high-temperature frying, which features prominently in Chinese cooking, as producing Group 2A carcinogens. This study simultaneously characterized particulate and gaseous-phase cooking emissions, monitored their reactive oxygen species (ROS) concentrations, and evaluated their impact on gene...

Presented in this paper is an in-depth analysis of the impact of engine start during various stages of engine warm up (cold, intermediate, and hot start stages) on the performance and emissions of a heavy-duty diesel engine. The experiments were performed at constant engine speeds of 1500 and 2000 rpm on a custom designed drive cycle. The intermedi...

In the present study, Mg0.25Fe2.75O4 nanocatalyst for reduction of emissions in diesel engine was fabricated via urea-nitrate combustion method. The effect of urea concentrations as fuel on its structural characteristics and Oxygen Storage Capacity (OSC) was thoroughly investigated. The results of various characterization analyses showed that fuel...

Aerosols deposited into the Great Barrier Reef (GBR) contain iron (Fe) and other trace metals, which may act as micronutrients or as toxins to this sensitive marine ecosystem. In this paper, we quantified the atmospheric deposition of Fe and investigated aerosol sources in Mission Beach (Queensland) next to the GBR. Leaching experiments were applie...

Four types of fuels blended with diesel in scaling proportion were used in a diesel engine to generate 13 different soot samples. The samples were characterised for their thermal-induced oxidation process with DSC and TGA from which the mass loss during each of three phases and 6 critical temperatures was obtained per sample. With the same samples,...

The airborne particulate matter (PM) is known to cause adverse pulmonary and cardiovascular health effects. This study investigated the diurnal characteristics of PM induced PM-bound ROS from real time measurements in typical roadside and urban background sites in Hong Kong, and identified potential influencing factors to its variation in atmospher...

This study investigates the effect of engine temperature during cold start and hot start engine operation on particulate matter emissions and engine performance parameters. In addition to a fundamental study on cold start operation and the effect of lubricating oil during combustion, this research introduces important knowledge about regulated part...

The industrial combustion of biomass, which has always been considered a source of clean and sustainable energy, might be phased out in China because it is believed to cause extremely high emissions of volatile organic compounds (VOCs), which are the key precursors in the formation of ozone and haze, although the emission factors have rarely been m...

The concentration, nature and persistence of particulate matter (PM)-bound reactive oxygen species (ROS) is of significant interest in understanding how atmospheric pollution impacts health. However, the inherent difficulties in their measurement, particularly regarding the so called “short-lived” ROS, have limited our understanding of their persis...

Nitrogen (N) content in algae hydrothermal liquefaction (HTL) biocrude is high (5–8 wt%) and generally presumed to result in high NOx emissions during combustion. However, to our knowledge a very limited previous work on diesel engine performance and emissions of N-containing fuels. In order to investigate this issue, pyridine, an N-heterocyclic co...

To estimate the oxidative potential (OP) of particulate matter (PM), two commonly used cell-free, molecular probes were applied: dithiothreitol (DTT) and dichloro-dihydro-fluorescein diacetate (DCFH-DA), and their performance was compared with 9,10-bis (phenylethynyl) anthracene-nitroxide (BPEAnit). To the best of our knowledge, this is the first s...

This study investigated the real-time NOx emissions from a heavy-duty diesel truck and a bulk carrier ship. The test road vehicle was driven on a combination of a flat and hilly route from Brisbane to Toowoomba that covered urban, rural and motorway driving. On-board ship emissions were measured on the sea from the port of Gladstone to Newcastle. N...

The Sydney Particle Study involved the comprehensive measurement of meteorology, particles and gases at a location in western Sydney during February–March 2011 and April–May 2012. The aim of this study was to increase scientific understanding of particle formation and transformations in the Sydney airshed. In this paper we describe the methods used...

Abstract. Cloud-radiation interactions over the Southern Ocean are not well constrained in climate models, in part due to uncertainties in the sources, concentrations and cloud-forming potential of aerosol in this region. To date, most studies in this region have reported measurements from fixed terrestrial stations or a limited set of instrumentat...

Rising concerns over environmental and health issues of internal combustion engines, along with growing energy demands, have motivated investigation into alternative fuels derived from biomasses, such as biodiesel. Investigating engine and exhaust emission behaviour of such alternative fuels is vital in order to assess suitability for further utili...

Metallic composition of diesel particulate matter, even though a relatively small proportion of total mass, can reveal important information regarding engine conditions, fuel/lubricating oil characteristics and for health impacts. In this study, a detailed investigation into the metallic elemental composition at different particle diameter sizes ha...

This manuscript details the application of a profluorescent nitroxide (PFN) for the online quantification of radical concentrations on particulate matter (PM) using an improved Particle Into Nitroxide Quencher (PINQ). A miniature flow-through fluorimeter developed specifically for use with the 9,10-bis(phenylethynyl)anthracene-nitroxide (BPEAnit) p...

In this study, emission factors of both particle and gaseous phases are characterised on board two large cargo vessels operating on the east coast of Australia during manoeuvring conditions. In order to investigate the difference in particle number and mass size distributions, measurements were conducted on two 2-stroke engines of two vessels using...

Air pollution exposure is associated with a range of adverse health effects, including cardiovascular and respiratory diseases. Particle-bound ROS has been recognised as one of the prevailing parameters to indicate the toxic potential of airborne particulate matter (PM). The temporal variability of particle-bound ROS is a very important metric cruc...

The aerosol driven radiative effects on marine low-level cloud represent a large uncertainty in climate simulations, in particular over the Southern Ocean, which is also an important region for sea spray aerosol production. Observations of sea spray aerosol organic enrichment and the resulting impact on water uptake over the remote southern hemisph...