Superhydrophobic properties of nonaligned boron nitride nanotube films

Superhydrophobicity is highly desirable for numerous applications. Here, we report that a semierect but nonaligned boron nitride nanotube (BNNT) film showed superhydrophobicity with contact angle above 170° and a small contact angle hysteresis. This superhydrophobicity was stable over a large range of drop sizes, and the measured critical transition pressure was about 10 kPa. However, the prostrate BNNT films only showed hydrophobicity. The drop retraction behavior during evaporation, the pressure effect on contact angle, the critical transition pressure, the drop impact behavior, and the self-cleaning efficiency between these two kinds of films were systematically investigated and compared.

Inspection of drop-weight impact damage in woven CFRP laminates fabricated by different processes

The influence of manufacturing process on the drop-weight impact damage in woven carbon/epoxy laminates was inspected by visual observation, dyepenetrant X-ray technique, and optical microscopy observation. The MTM56/ CF0300 woven quasi-isotropic laminates were fabricated by two processes: the autoclave and the Quickstep processes. Quickstep^TM is a novel composite manufacturing process, which was designed for the out-of-autoclave production of high-quality composite parts at lower cost. It utilizes higher heat conduction of fluid other than gas to transfer heat to components, which results in much shorter cure cycles. The laminates cured by this fast heating process showed different impact failure modes from those cured by the conventional autoclave process. The residual indentation in the top side of the Quickstep-cured laminates had a bigger diameter, but a smaller depth at the same impact energy level. Dye-penetrant X-ray revealed more intense and connected impact damage regions in the autoclave-cured laminates. Optical micrography as a supplementary method showed less severe matrix damage in the quickstep-cured laminates indicating a more ductile property of the resin matrix cured at a faster heating rate.

An experimental study of low velocity impact response in 2/2 twill weave composite laminates manufactured by a novel fabrication process

A novel fabrication process for advanced composite components—the QuicktepTM process was described. 2/2 twill weave MTM56/CF0300 carbon epoxy composite laminates were manufactured by the Quickstep and the autoclave processes. The response of these laminates to drop-weight low velocity impact at energy levels ranging from 5 to 30 J was investigated. It was found that the laminates fabricated by the Quickstep had better impact damage tolerance than those fabricated by the autoclave. Optical microscopy revealed extensive matrix fracture in the center of the backside of the autoclave laminates indicating the more brittle property of the epoxy matrix cured by the autoclave process. Interfacial shear strength (IFSS) for two composite systems were measured by micro–debond experiments. The MTM56/CF0300 material cured by the Quickstep showed stronger fibre matrix adhesion. Since the thickness and density of the impact targets produced by two processes were different, finite element analysis (FEA) was performed to study the effect of these factors on the impact response. The simulation results showed that the difference in thickness and density affects the stress distribution under impact loading. Higher thickness and lower density caused by processing lead to less endurance to drop weight impact loading. Therefore the better performance of Quickstep laminates under impact loading was not due to the thickness and density change, but resulted from stronger mechanical properties.

Time series analysis of the impact of tobacco control policies on smoking prevalence among Australian adults, 2001–2011

Objective: To determine the impact of tobacco control policies and mass media campaigns on smoking prevalence in Australian adults.
Methods: Data for calculating the average monthly prevalence of smoking between January 2001 and June 2011 were obtained via structured interviews of randomly sampled adults aged 18 years or older from Australia’s five largest capital cities (monthly mean number of adults interviewed: 2375). The influence on smoking prevalence was estimated for increased tobacco taxes; strengthened smoke-free laws; increased monthly population exposure to televised tobacco control mass media campaigns and pharmaceutical company advertising for nicotine replacement therapy (NRT), using gross ratings points; monthly sales of NRT, bupropion and varenicline; and introduction of graphic health warnings on cigarette packs. Autoregressive integrated moving average (ARIMA) models were used to examine the influence of these interventions on smoking prevalence.
Findings: The mean smoking prevalence for the study period was 19.9% (standard deviation: 2.0%), with a drop from 23.6% (in January 2001) to 17.3% (in June 2011). The best-fitting model showed that stronger smoke-free laws, tobacco price increases and greater exposure to mass media campaigns independently explained 76% of the decrease in smoking prevalence from February 2002 to June 2011.
Conclusion: Increased tobacco taxation, more comprehensive smoke-free laws and increased investment in mass media campaigns played a substantial role in reducing smoking prevalence among Australian adults between 2001 and 2011.

Counting the cost: the impact of cinema ticket prices in Australia

The authors discuss the change in cinema ticket price and its effect on audience perception on cinema attendance in Australia. Topics discussed include the comparison of ticket prices in Australia to countries such as the U.S., Japan, and New Zealand, the reason of high ticket prices in Australia such as high wages in theatre operation and piracy, and the drop of cinema admission as result of high ticket prices. They mention the social equity issues raised by the high cost of cinema tickets.