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Nitrate removal or denitrification, involves reduction of nitrate into nitrogen and oxygen. The use of nanoparticles zero valent metals for denitrification receives great attention as they have been proven to be effective and environmentally safe. In this work, the nanoparticles were prepared by reducing the metals salts, dissolved in a mixed solution of water and ethanol, using sodium borohydrate. The nitrate reduction reaction took place in an ambient environment – room temperature, neutral pH and aerobic condition. Results from the experiments carried out showed that nitrate has been successfully reduced up to a maximum of 40% in all the samples without an increase in the pH of the solution, a strong indication that ammonia was not produced. As for the study on the reactivity of the recycled NZVI, the samples synthesized with 4:1 (v/v) ethanol/water and using 9: 1 (v/v) ethanol/water, the reactivity of the iron is similar to the fresh NZVI for the first two hours of the study.

Negative thermal expansion (NTE) and negative Poisson’s ratio (NPR) are counterintuitive material properties that have gained popularity as the focus of many recent works. However, most of the structures previously studied only exhibit NTE or NPR exclusively. One important structure that has already been shown to exhibit NPR is the re-entrant triangle. In this work, the property of NTE in re-entrant triangular cellular structure composed of welded/bonded/brazed ribs of two different materials is investigated via analytical and finite element (FE) modelling. Based on analytical and FE analysis, the geometrical and material parameters for attaining NTE in the re-entrant metamaterial are established. The analysis and simulations reveal the dependence of NTE on the inclination of the longer chevron strut, the dimensionless rod coefficient of thermal expansion (CTE), the ratio of thermal expansion coefficients of constituent struts but independent of scale and temperature. The extent of this property becomes more negative for higher values of the angle of the longer chevron strut with the vertical, higher ratios of CTE of the base to chevron strut material and for lower values of the non-dimensional re-entrant base material thermal expansion coefficient. The anisotropic and NTE behaviour is stretch-dominated. Effectively, combined with previous knowledge of NPR in the re-entrant triangle, NTE leads to further significance of such structures for many thermal and mechanical applications, such as composite materials, sensors and electronic components industries in both thermal and mechanical applications.

Biological and pharmaceutical (B&P) products are essential in modern life. Currently, the demand and requirements of these products are dramatically growing; product quality and integrity then become crucial. As a key factor for ensuring quality and integrity, the current product status monitoring system needs to be enhanced in a more sophisticated and comprehensive way. This research describes the design of a wireless sensor network (WSN) monitoring system for B&P products supply chain management. In this study, the system architecture is presented based on the proposed framework. The framework consists of three processes: the first one is to generate a WSN with full coverage, the second one is to determine the optimal position of the sink, and the last process is to add additional relay nodes for providing fault tolerance to the network. Finally, a feasibility test on B&P product storage in a hospital is conducted. The proposed system provides a systematic approach for the deployment of sensor nodes and relay nodes. It also provides a relatively simple and rapid method for industries in general to follow and implement when designing a WSN system.

The healthcare industry has been focusing efforts on optimizing inventory management procedures through the incorporation of Information and Communication Technology, in the form of tracking devices and data mining, to establish ideal inventory models. In this paper, a roadmap is developed towards a technological assessment of the Internet of Things (IoT) in the healthcare industry, 2010–2020. According to the roadmap, an IoT-based healthcare asset management system (IoT-HAMS) is proposed and developed based on Artificial Neural Network (ANN) and Fuzzy Logic (FL), incorporating IoT technologies for asset management to optimize the supply of resources.