Evaluation of an evaporation suppressing monolayer system in a controlled wave tank environment: a pilot investigation

Due to long-term drought conditions coupled with the apparent influence of global warming, compounding water loss has been a very serious issue across the vast majority of the Australian continent. During these drought conditions, the evaporative effect outweighs the amount of precipitation being received on a year to year basis. Several methods have been introduced in recent history to inhibit the amount of evaporative loss from various types of water bodies such as the application of thin layer chemical films (monolayers). A series of solvent, solid and suspension derived prototype monolayers, based on ethylene glycol monooctadecyl ether (C18E1), are examined in this current study as an approach to eliminate the problems seen to occur with the previous types of monolayers. This research evaluates the fundamental effect of wind and wave based activity upon these prototype monolayers in an atmospherically controlled enclosure positioned over a large extended water tank using real-time environmental measurements. Selected performance results for the prototype monolayers as measured within the enclosed water tank were compared to results measured from a control monolayer film based on a commonly used octadecanol suspension film. The results show that under varying wind and wave conditions the prototype monolayers inhibit evaporation at a level similar to or better than the octadecanol standard, even when delivered at lower raw dosages.

The e-health literacy framework: A conceptual framework for characterizing e-health users and their interaction with e-health systems

In current e-health research and development there is a need for a broader understanding of the capabilities and resources required for individuals to use and benefit from e-health services, i.e. their e-health literacy. The aim of
this study was to develop a new conceptualisation of e-health literacy with consideration of the experiences of a wide range of stakeholders and in alignment with current technologies. Concept mapping was used to generate a comprehensive and grounded model of e-health literacy. Concept mapping workshop participants included patients, health professionals and medical informatics experts. Eight workshops, carried out in Denmark and United Kingdom, generated 450 statements, separated into 128 clusters. Through an inductive structured analysis, seven domains were identified: 1. Ability to process information, 2. Engagement in own health, 3. Ability to engage actively with digital services, 4. Feeling safe and in control, 5. Motivation to engage with digital services, 6. Having access to systems that work, and 7. Digital services that suit individual needs. These empirically derived domains form an e-health literacy framework (eHLF) and provide new insights into the user’s ability to understand, access and use e-health technologies. The eHLF offers a framework for evaluating an individual’s or a population’s capacity to understand, use and benefit from technology to promote and maintain their health. Such a framework also provides a potential checklist for the development and improvement of e-health services.

A study of guided wave propagation in timber pole using spectral finite element method

Timber is one of the most widely used structural material all over the world. Round timbers can be seen as a structural component in historical buildings, jetties, short span bridges and also as piles for foundation and poles for electrical and power distribution. To evaluate the current condition of these cylindrical type timber structures, guided wave has a great potential. However, the difficulties associated with the guided wave propagation in timber materials includes orthotropic behaviour of wood, moisture contents, temperature, grain direction, etc. In addition, the effect of fully or partially filled surrounding media, such as soil, water, etc. causes attenuation on the generated stress wave. In order to investigate the effects of these parameters on guided wave propagation, extensive numerical simulation is required to conduct parametric studies. Moreover, due to the presence of multi modes in guided wave propagation, dispersion curves are of great importance. Even though conventional finite element method (FEM) can determine dispersion curves along with wave propagation in time domain, it is highly computationally expensive. Furthermore, incorporating orthotropic behaviour and surrounding media to model a thick cylindrical wave (large diameter cylindrical structures) make conventional FEM inefficient for this purpose. In contrast, spectral finite element method (SFEM) is a semi analytical method to model the guided wave propagation which does not need fine meshes compared to the other methods, such as FEM or finite difference method (FDM). Also, even distribution of mass and stiffness of structures can be obtained with very few elements using SFEM. In this paper, the suitability of SFEM is investigated to model guided wave propagation through an orthotropic cylindrical waveguide with the presence of surrounding soil. Both the frequency domain analysis (dispersion curves) and time domain reconstruction for a multi-mode generated input signal are presented under different loading location. The dispersion curves obtained from SFEM are compared against analytical solution to verify its accuracy. Lastly, different numerical issues to solve for the dispersion curves and time domain results using SFEM are also discussed.

Occurrence of anodic current and corrosion of steel in aqueous media under fluctuating cathodic protection potentials

Excursion of cathodic protection (CP) potential from the designed "safe" CP level resulting from various forms of electrical interference signals are observed rather frequently in industrial applications, in particular in the pipeline industry; however, the influence of such potential fluctuations on the corrosion behavior of steel under CP conditions does not yet appear to be fully understood. In this work, the effects of anodic transients that periodically shift the potential of a CP protected steel electrode from-1,200 mVAg/AgCl to-750 mVAg/AgCl on the corrosion of a steel electrode in aqueous media was investigated using square wave polarization. Anodic currents were measured that lasted for significant periods of time upon stepping the CP potential up to a less cathodic potential at various frequencies (1 h, 30 s, 10 s, 5 s, and 1 s). Part of such anodic currents is found to cause steel corrosion, and this is explained on the basis of understanding the Fe/H2O equilibrium.