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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 Heavy Fuel Oil (HFO) with nearly the same sulphur content. Results showed that manoeuvring compared to ocean-going conditions resulted in higher emission factors for carbon monoxide (CO), carbon dioxide (CO2), unburnt hydrocarbon (HC), particulate matter (PM) and particle number (PN), which can have significant negative effects on human health and the environment in coastal and port areas. Importantly, a significant difference was observed in particle number size distributions between the two vessels. Those observed for Vessel II were mono-modal with the peak at 40–50 nm and dominated by ultrafine particles (D < 100 nm), while for Vessel I a bimodal distribution with a nucleation peak at around 20 nm and a major peak at larger diameter of 60 nm was observed. The difference in particle number size distributions between the two vessels may be due to the difference in sampling location and/or marine engine characteristics, including age and technology. The effects of fuel sulphur content on PN and PM emissions observed in this study are also compared with the results available from previous measurements in the literature. Engine load was also found to be an important influence on all emission factors. Keywords: Ship emissions, Manoeuvring conditions, Emission factors, Sulphur content, Particle number size distributions

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 particulate number emissions and particulate size distribution during cold start, which is an emerging area in the literature. A further aspect of this work is to introduce waste lubricating oil as a fuel. By using diesel and two blends of diesel with 1 and 5% waste lubricating oil in a 6-cylinder turbocharged engine on a cold start custom test, this investigation studied particle number (PN), friction losses and combustion instability with diesel and waste lubricating oil fuel blends. In order to understand and explain the results the following were also studied: particle size distribution and median diameter, engine oil, coolant and exhaust gas temperatures, start of injection, friction mean effective pressure (FMEP), mechanical efficiency, coefficient of variation (CoV) of engine speed, CoV of indicated mean effective pressure (IMEP) and maximum rate of pressure rise were also studied. The results showed that during cold start the increase in engine temperature was associated with an increase in PN and size of particles, and a decrease in FMEP and maximum rate of pressure rise. Compared to a warmed up engine, during cold start, PN, start of injection and mechanical efficiency were lower; while FMEP, CoV of IMEP and maximum rate of pressure rise were higher. Adding 5% waste lubricating oil to the fuel was associated with a decrease in PN (during cold start), decreased particle size, maximum rate of pressure rise and CoV of IMEP and was associated with an increase in PN and nucleation mode particles (during hot start) and FMEP.

This paper studies the detection limit, selectivity and counting efficiency of an Ultraviolet Aerodynamic Particle Sizer Spectrometer (UVAPS) with regard to aerosolized fungal spores. The study demonstrated the ability of the instrument for detection and measurement of fungal spores under controlled conditions. A reasonable correlation was found between the UVAPS and the AGI-30 impinger in measuring the aerosol fungal spore concentrations under investigation: Penicillium and Aspergillus niger (r = 0.911, p < 0.005 and r = 0.882, p < 0.05, respectively). A linear relationship between total particle concentration and fluorescent particle concentration was found in the range from 0 to 70 particles/cm3. Its lower detection limit was found to be 0.01 particles/cm3. The dry generation method which was used for generating fungal spores has proved to be reproducible and easy to control, as well as simple and inexpensive

The Ultraviolet Aerodynamic Particle Sizer (UVAPS) is a novel aerosol counter for realtime monitoring of viable bioaerosols. The previous validation studies on the UVAPS were either laboratory based or were conducted outdoor with the artificially generated aerosols. In this study, the spectrometer was applied to investigate particulate pollution inside a swine confinement building (SCB). Real-time capabilities of the instrument were used to investigate the effect of on-farm-activities, such as an effluent flushing with recycled water, on microbial load inside the SCB. In addition to the UVAPS, monitoring of viable bioaerosols (bacteria and fungi) was simultaneously conducted with the sixstage Andersen microbial impactor and the AGI-30 impingers. The UVAPS measurements showed that the concentrations of both total and biological particles inside the SCB were in order of 106 -107 particles/ m3. These concentrations were approximately seven times the outside concentrations for total particles and up to 12 times for biological particles. Approximately 95 % of both total and biological particles were respirable (< 7mm) and approximately 60 % of total and 50 % of biological particles accounted for the fine particle fraction (

This study evaluated the effect of bacterial physiology, such as physiological age and stress, on the performance of the Ultravioloet Aerodynamic Particle Sizer (UV-APS, model 3312, TSI Inc., St. Paul, MN). Intensity of the fluorescent signals was measured for three bacteria having various sensitivities to environmental stresses, Bacillus subtilus (spores and vegetative cells), Pseudomonas fluorescens, and Micrococcus luteus. The performance of the UVAPS was found to depend on the type of airborne bacteria. In addition, the fluorescence signals for stationary-phase bacteria were generally stronger than for their log-phase counterparts. These results indicated that bacterial injury due to environmental stresses has a strong influence on the measured fluorescence signals. This hypothesis was confirmed by obtaining a linear relationship between the percentage of fluorescent particles and the proportion of injured bacteria in the total population of cultivable bacteria in samples simultaneously collected with the AGI-30 impingers. This indicates that the amount of fluorophors (specifically NADH) within injured bacteria is below the UVAPS sensitivity level. The practical implications of these findings are discussed in the paper. The reported results contribute to broadening our understanding of the method and may assist in developing sampling strategies for the application of the UVAPS to various bioaerosol studies.

Thermal and electronic transport properties of low-doped single crystal InSb were determined for the first time and analyzed using a photoacoustic frequency heat transmission technique. The thermal diffusivity, excess carrier lifetime, front and rear side recombination velocity and electronic diffusivity were determined by comparing experimental results and theoretical photoacoustic signals.