The ultraviolet (UV) radiation environment consists of direct UV and diffuse UV components. The ratios of diffuse-to-direct UV for the UVB, UVA, and the erythema UV wavebands are influenced by clouds, aerosols, albedo, and surface reflectance, Rayleigh scattering, and solar zenith angle. At times, the relative proportion of diffuse UV may be higher than the direct UV, for example, on cloudy days or days with high atmospheric aerosols. Consequently, exposures due to diffuse UV radiation play a significant role in the UV exposure received by human subjects. Diffuse UV radiation contributes to the risk of skin cancer and sun-related eye disorders. Reducing personal exposure to diffuse UV by physical protection, including tree shade, purpose-built shade structures, protection by hats, and eyewear, is more difficult than reducing direct UV exposure due to the diffuse UV being incident from all directions. The UV index reported to the public represents the sum of the direct and the diffuse erythema UV, with no information provided specifically on the diffuse UV component. This paper reviews the factors that contribute to diffuse UV exposures affecting human populations. It examines diffuse UV modeling techniques, and broadband and spectral component measurements.

Spectroradiometry, radiometry, and dosimetry are employed for the measurement of ultraviolet radiation (UVR) irradiance and non-ionizing exposure. Different types of UVR dosimeter have been developed for measuring personal and environmental UVR exposures since film dosimetry was pioneered in the 1970s. An important type of dosimeter is the thin film variant, which contains materials that undergo changes in optical absorbance when exposed to UVR. These changes can be measured at a specific wavelength using a spectrophotometer. Thin film dosimeters allow UVR exposure measurements on humans at various body sites during daily activities, as well as on plants, animals, and any sites of interest when utilized in a field environment. This review examines the properties and applications of five types of thin film UVR dosimeter that have different dynamic exposure limits and spectral responses. Polysulphone, with a spectral response approximating the human erythema action spectrum, was one of the first materials employed in thin film form for the measurement of UVR exposures up to 1 day, and up to 6 days with an extended dynamic range filter. Polyphenylene oxide has been characterized and employed for personal UVR exposure measurements up to approximately four summer days and has also been used for long-term underwater UVR exposures. Phenothiazine and 8-methoxypsoralen have been reported as suitable for the measurement of longer wavelength UVA exposures. Finally, polyvinyl chloride with an extended dynamic exposure range of over 3 weeks has been shown to have predominantly a spectral response in the UVB and extending up to 340 nm.

Abstract Introductory physics courses cover the gravitational and electromagnetic force in some detail, but the strong and weak nuclear forces are often given only a cursory treatment. This paper presents some ideas for teaching students about the strong force using practical hands-on demonstrations and using the strong force potential in teaching certain aspects of calculus. A good analogy to the strong force is to place a strong magnet on a metal whiteboard. The magnet must be very close to the board for the magnet to stick to the metal exemplifying the short range of the strong force. Another analogy that can easily be demonstrated in the classroom is placing two cylindrical magnets with facing like poles in a vertically oriented Perspex tube. Velcro is another analogy since the strong force acts over such a short range it is essentially a contact force. The plot of the strong force versus distance and strong potential versus distance is a practical way of teaching students the reciprocal relationship between differentiation and integration. The Reid potential model of the strong interaction (Reid 1968 Ann. Phys., NY 50 411–448) is a good example of differentiating and integrating exponential functions. A calculation is included that shows that the strong force is approximately 100 times stronger than the electromagnetic force. A link between the strong force and Heisenberg uncertainty principle is also made.

In outdoor air conditioning (AC) systems, a fine spray of water mist is used to evaporate water and extract heat from the air. Misting systems use high pressure nozzles to produce water drops 5 μ m in diameter. This dramatically increases the surface area of the water–air interface for a given volume of water facilitating heat transfer from air to water. Small drops stay suspended in the air for a sufficient amount of time to allow complete evaporation. An example of a misting system in operation at a Café in Montville, Queensland, Australia is discussed. As well as being cheaper to run, misting systems are less harmful to the environment since they reduce the dependence on indoor AC. This is an important topic to discuss with students in relation to climate change. A classroom experiment suitable for senior secondary and first-year university students is described in which a fan is used to blow air across a shallow container of water placed on an electronic balance. The experiment was performed throughout the day and night during periods of low and high humidity. Data collected from this experiment indicated that evaporation was much higher during the day than at night. In view of climate change and global warming, heat, energy and evaporation are important subjects to teach students, especially considering that these students will soon be adults making important decisions around sustainability and environmental protection in their day-to-day lives, and develope future policies to mitigate the impact of climate change.

Triathletes present an extreme case of modelled behaviour in outdoor sport that favours enhanced exposure to solar ultraviolet radiation. This research presents personal solar ultraviolet exposures, measured using all-weather polysulphone film dosimeters, to triathletes during the distinct swimming, cycling and running stages of competitive Sprint, Olympic and Ironman events conducted within Australia and New Zealand. Measurements of exposure are made for each triathlon stage using film dosimeters fixed at a single site to the headwear of competing triathletes. Exposures are expressed relative to the local ambient and as absolute calibrated erythemally effective values across a total of eight triathlon courses (two Ironman, one half Ironman, one Olympic-distance, and four Sprint events). Competitor exposure results during training are also presented. Exposures range from between 0.2 to 6.8 SED/h (SED: standard erythema dose) depending upon the time of year, the local time of each event and cloud conditions. Cycle stage exposures can exceed 20 SED and represent the highest exposure fraction of any triathlon (average = 32%). The next highest stage exposure occurred during the swim (average = 28%), followed by the run (average = 26%). During an Ironman, personal competitor exposures exceed 30 SED, making triathlon a sporting discipline with potentially the highest personal ultraviolet exposure risk.

Sport is an integral and enduring part of many societies, such as Australia. Participation in outdoor sports, such as tennis, comes with a very real risk of dangerous solar ultraviolet exposure which can result in erythema (sunburn), serious conditions such as skin cancer, including melanoma, and eye conditions such as cataracts and pterygium. This study remotely assesses the effective ultraviolet exposures in response to the increased sun safety awareness at a major summertime tennis tournament in Australia. The assessment only uses publicly accessible data and information. It was found that tournament organizers have effectively adopted sun‐safe protocols into the uniform policy that the court officials (judges and ball kids) are mandated to follow. The combination of sun‐participant geometry and the photoprotection provided by uniforms significantly reduced the ambient ultraviolet exposure, which was recorded to be as high as 9.9 SED h−1, to just 1.0 and 0.5 SED h−1 for ball kids and judges, respectively, compared to up to 2.0 SED h−1 for players. Even though caution is needed against complacency with sun safety, with the need for the court officials and the players to still apply sunscreen, the court officials provided persistent visual role modeling of sun‐safe behaviors.

Kiteboarding is an aquatic sporting discipline that has not yet been considered in the literature to date in terms of solar ultraviolet radiation (UVR) measurement. Kiteboarders need to look upward and are placed obliquely relative to the horizon when towed behind an overhead kite over a reflective water surface. This research defines the typical body surface orientation of a kiteboarder in motion through video vector analysis and demonstrates the potential risk to ocular and skin surface damage through practical measurement of solar UVR using a manikin model. Video analysis of 51 kiteboarders were made to construct skeletal wireframes showing the surface orientation of the leg, thigh, spine, humerus, lower arm and head of a typical kiteboarder. Solar UVR dosimeter measurements made using a manikin model demonstrate that the vertex and anterior surfaces of the knee, lower leg, and lower humerus received 89%, 90%, 80% and 63% of the available ambient UVR respectively for a typical kiteboarder who is tilted back more than 15o from vertical while in motion. Ocular (periorbital) exposures ranged from 56 to 68% of ambient. These new findings show that the anterior skin surfaces of kiteboarders and the eye are at elevated risk of solar UVR damage.

Kiteboarding is an aquatic sporting discipline that has not yet been considered in the literature to date in terms of solar ultraviolet radiation (UVR) measurement. Kiteboarders need to look upward and are placed obliquely relative to the horizon when towed behind an overhead kite over a reflective water surface. This research defines the typical body surface orientation of a kiteboarder in motion through video vector analysis and demonstrates the potential risk to ocular and skin surface damage through practical measurement of solar UVR using a manikin model. Video analysis of 51 kiteboarders was made to construct skeletal wireframes showing the surface orientation of the leg, thigh, spine, humerus, lower arm and head of a typical kiteboarder. Solar UVR dosimeter measurements made using a manikin model demonstrate that the vertex and anterior surfaces of the knee, lower leg and lower humerus received 89%, 90%, 80% and 63% of the available ambient UVR, respectively, for a typical kiteboarder who is tilted back more than 15° from vertical while in motion. Ocular (periorbital) exposures ranged from 56% to 68% of ambient. These new findings show that the anterior skin surfaces of kiteboarders and the eye are at elevated risk of solar UVR damage.

Personal solar ultraviolet radiation exposure models were developed for 144 Olympic events scheduled outdoors from across the 33 sport disciplines that will compete in Tokyo between 24 July and 9 August 2020. Ambient exposure models were developed from existing atmospheric parameters measured over Tokyo (35.7°N 139.7°E) and were used to weight erythemally effective solar ultraviolet exposure to gold medalists, taking into account body posture and expected protection by competitor's clothing which was assessed in comparison to respective medalists of the 2016 Rio Olympics. Individual exposure models consider the ultraviolet surface albedo (lawn, concrete, water or sand) and timing of daily events held within Olympic venues. Exposure assessments are presented, including assessments of all preliminary rounds and qualifiers. Within scheduled outdoor events, we award first place (representing the highest and most harmful UV exposure) to the women's tennis singles (1680 J/m2), second to men's golf (1530 J/m2) and third to the men's cycling road race (941 J/m2) for the highest expected erythemally effective solar ultraviolet radiation exposures of the 2020 Tokyo Games. The highest expected solar ultraviolet exposures for nations expected to win greater than three gold medals among the outdoor events were found to occur in athletes from Kenya followed closely by the United States and Hungary. Gold medalists from South Korea were found to demonstrate the highest level of sun protection due to clothing at the 2016 Rio Games, and are thus expected to receive the greatest relative reduction in erythemally effective exposure during the 2020 Tokyo Games.

Thin film dosimeters have been used for the measurement of solar radiation since the 1970s. Their application includes personal exposure measurement and environmental exposure monitoring. Polyphenylene oxide (PPO) films have recently been developed for use in various underwater environments. These dosimeters are capable of measuring solar ultraviolet-B (UVB, 290 – 315 nm), which is a recognized physical stressor of corals when combined with elevated water temperatures occurring within the irregular structure of a coral reef. We present preliminary findings employing a newly developed PPO dosimeter clamp deployed upon reef building corals situated within turbid inshore waters of the Great Sandy Marine Park, Southern Queensland, Australia. UVB exposures measured over a 24 hour period during peak summer exposure conditions ranged from 12.11 kJ m-2 to 21.13 kJ m-2. This preliminary data showed a clear dependence on reef aspect with the highest exposures incident upon north facing (Southern Hemisphere) reef surfaces. We conclude that exposure stress to corals may still occur in shallow turbid water with UVB exposure being strongly associated with reef aspect.

This book provides the latest information on water reuse applications with a focus on urban areas. It examines numerous new and alternative methods for sustainable water supplies.

The emissions of various types ot greenhouse gases (GHGs) from natural and industrial sources are undergoing a great deal ot scrutiny around the world. The three main GHGs that are of most concern are carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). CO2, N2O and CH4 are all efficient absorbers and emitters of thermal infrared radiation, and as a result, once they are emitted into the atmosphere, they can contribute directly to the greenhouse effect. One of the most popular GHG measurement techniques is near dispersive infrared (NDIR) gas analysis. This paper describes a high school Physics or general science practical exercise that uses an inexpensive NDIR based gas analysis unit combined with a gas capture hood to measure CO2 gas flux from different water types and soil/fertiliser combinations. From this, students will gain an understanding of how GHGs are emitted from natural sources and how they are measured by scientists.

Fringing coral reefs provide a unique opportunity to study shallow aquatic ecosystems. A fringing coral reef system located in close proximity to a developed region was considered in this study. In such an environment, the rate of decay of dissolved organic matter is high and the penetration of higher energy ultraviolet‐B ( UVB ) extends a greater influence on species diversity, particularly upon shallow benthic communities. Results from a 9 month subsurface UVB exposure measurement campaign performed at a site located on the southern Q ueensland coast ( H ervey B ay, 25°S) are presented in this research. For this, a novel dosimetric technique was utilized to measure long‐term subsurface UVB exposures. The resultant data set includes exposure measurements made during the significant La Niña event of late 2010 which resulted in unprecedented high sea surface temperatures and severe flooding across eastern Australia, impacting upon the lagoon regions of the G reat B arrier R eef and Q ueensland's southern estuaries, including the study site. The influence of season, diurnal tidal variation, cloud cover and solar zenith angle were analyzed over the campaign period. Mean minimum daylight water depth was found to be the most significant factor influencing subsurface UVB .

Dosimeters are used in measuring received ultraviolet (UV) radiation by humans and plants. Previously dosimeters 3.0cm×3.0cm weighing 0.6g, using poly(2,6-dimethyl-1,4-phenylene oxide) (PPO)(1) as the photoactive material have been used. A smaller 1.0cm×1.5cm flexible PPO dosimeter weighing 0.05g has been developed and characterised in this research. Laboratory and field studies show that the miniaturised dosimeter measures comparative results to the larger dosimeters for cosine response, dark reaction and dose response. The smaller, flexible dosimeters are also more applicable for use on curved surfaces and have less impact on the orientation of plant leaves due to their decreased mass. This research has also shown that miniaturised PPO dosimeters can be successfully employed on plant and human subjects to accurately determine biologically active UV distributions. The miniaturised PPO dosimeters allow for more measurements over an exposed area and the PPO film allows for measurements to be made for periods longer than 1day. The combination of smaller size and longevity of the photoactive material allows for more flexibility in future UV field research resulting in an increase in the potential number of environments where UV dosimeters can be deployed.

Fugitive emissions of methane (CH4) and nitrous oxide (N2O) are known to be produced and released by wastewater treatment processes. CH4 and N2O emissions from large-scale, high-volume centralized wastewater treatment plants (WWTPs) have been well documented and quantified by online gas analysis instrumentation and grab sampling techniques. However, there is minimal information available on the extent of the fugitive emissions released at small-scale decentralized WWTPs treating smaller daily volumes of sewage, particularly those running a treatment regime with a membrane bioreactor (MBR) system. To ascertain the amount of fugitive emissions produced by these decentralised WWTPs, a series of CH4 and N2O gas flux measurements were performed at four different Australian small-scale WWTPs over the months of autumn and winter in 2012. Three of these WWTPs were using an activated sludge treatment scheme, and one employed an MBR system. It was found that under certain biochemical conditions, decentralized activated sludge WWTPs can emit greatly variable, but still significantly high, levels of CH4 and N2O (17 g CH4 m-2 d-1 and 12 g N2O m-2 d-1 at their peak), most particularly from aeration tanks. In addition, CH4 emissions as high as 2.5 g CH4 m-2 d-1 were measured from the anaerobic tank of the MBR system, which were not predicted by previous modelling studies.

The decentralisation of wastewater treatment operations exposes several environmental consequences. This includes the fugitive emission of two greenhouse gases, nitrous oxide (N 2 O) and methane (CH 4 ). The magnitude of these emissions is presently unclear. Therefore, it is necessary to measure the extent of the release of N 2 O and CH 4 gas from decentralised wastewater treatment plants (WWTPs) in order to quantify the impact these emissions will have on the environment and to determine strategies to reduce them. Specifically, this pilot study employed an online non-dispersive infrared (NDIR) gas analyser and flux hood to evaluate the spatial and short-term temporal distribution of N 2 O and CH 4 flux over half a day, from an aeration tank system within a decentralised sewage mining plant. The aeration tank system was able to emit N 2 O fluxes of up to 11.6 g N 2 O m −2 day −1 and CH 4 fluxes of up to 1.1 g CH 4 m −2 day −1 . The N 2 O and CH 4 fluxes varied rapidly over short time intervals in the same position (as high as 45% for N 2 O and 36% for CH 4 ) and could almost triple in magnitude between two different positions across the surface of the aeration tank (within a distance no greater than 1.5 to 2 m).

The terrestrially available UVB was measured underwater on a fringing coral reef at the southern end of Australia's Great Barrier Reef marine park (25oS, 153oE) using poly 2,6-dimethyl-1, 4-phenylene oxide (PPO) film dosimeters. These dosimeters have been employed in previous research applications to measure long term terrestrial UV exposures on land and in controlled aquatic environments (typically for exposures lasting several days). The value of these dosimeters is discussed in reference to their use in an underwater coral reef environment extending over periods of several weeks. The UVB measured in the autumn at the test reef site indicates that exposures in a shallow coral reef located at a sub-tropical latitude vary from between 34 kJm-2 and 50 kJm-2 over a period of 28 days equating to a mean daily UVB exposure of between 1 and 2 kJm-2. These measurements made at an approximate depth of 2 m represent approximately 5% of the daily surface UVB. The results indicate that the film dosimeters used have the potential to be applied in a number of different underwater locations to investigate the impact of solar UV radiation on exposed coral surfaces.

Monolayers are highly desirable for their evaporation reducing capabilities due to their relatively minimal cost and ease of application. Despite these positive attributes, monolayers have consistently failed to perform effectively due to the harsh wind and wave conditions prevalent across real-world water reserves. An exhaustive and consistent study testing the influence of wind and wave combinations on monolayer performance has yet to be presented in the literature. To remedy this, the effect of simultaneous wind and wave conditions on a benchmark high-performance monolayer (octadecanol suspension, CH(3)(CH(2))(16)CH(2)OH) has been analysed. Subjected only to waves, the monolayer remained intact due to its innate ability to compress and expand. However, the constant simultaneous application of wind and waves caused the monolayer to break up and gather down-wind where it volatilised over time. At wind speeds above 1.3 m s(-1) the monolayer was completely ineffective. For wind speeds below this threshold, the monolayer had an influence on the evaporation rate dependent on wind speed. From these results a series of application protocols can now be developed for the optimised deployment of monolayers in real-world water reserves. This will be of interest to private, commercial and government organisations involved in the storage and management of water resources.

A practical exercise for developing a simple cost-effective solar ultraviolet radiation dosimeter is presented for use by middle school science students. Specifically, this exercise investigates a series of experiments utilising the historical blue print reaction, combining ammonium iron citrate and potassium hexacyanoferrate to develop an ultraviolet sensitive solution. The activity is intended for implementation into courses of study based on the new Australian science curriculum, and the strand Chemical reactions matter. The activity investigates rates of reaction and examines the influence of an invisible physical catalyst, solar radiation. The developed photochemical dye was tested for use as a solar dosimeter by painting or soaking various common materials with the solution. A soaked cloth dosimeter was determined to be the most practically appropriate. Its use as a 'magic cloth' or polyethylene filtered ultraviolet radiation dosimeter, capable of being calibrated to incoming solar radiation is discussed. The exercise is presented as a practical guide that can be followed by middle school aged science students beginning studies in physics, chemistry or the environment. The experiment may also be extended and applied to senior chemistry investigations.