Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 11 of 11

Full-Text Articles in Entire DC Network

Optical Sensing System Based On Wireless Paired Emitter Detector Diode Device And Ionogels For Lab-On-A-Disc Water Quality Analysis, Monika Czugala, Robert Gorkin Iii, Thomas Phelan, Jennifer Gaughran, Vincenzo Curto, Jens Ducree, Dermot Diamond, Fernando Benito-Lopez Jun 2015

Optical Sensing System Based On Wireless Paired Emitter Detector Diode Device And Ionogels For Lab-On-A-Disc Water Quality Analysis, Monika Czugala, Robert Gorkin Iii, Thomas Phelan, Jennifer Gaughran, Vincenzo Curto, Jens Ducree, Dermot Diamond, Fernando Benito-Lopez

Robert Gorkin III

This work describes the first use of a wireless paired emitter detector diode device (PEDD) as an optical sensor for water quality monitoring in a lab-on-a-disc device. The microfluidic platform, based on an ionogel sensing area combined with a low-cost optical sensor, is applied for quantitative pH and qualitative turbidity monitoring of water samples at point-of-need. The autonomous capabilities of the PEDD system, combined with the portability and wireless communication of the full device, provide the flexibility needed for on-site water testing. Water samples from local fresh and brackish sources were successfully analysed using the device, showing very good correlation …


Polymer Based Nanocomposites With Nanofibers And Exfoliated Clay, Michael Meador, Darrell Reneker Jul 2014

Polymer Based Nanocomposites With Nanofibers And Exfoliated Clay, Michael Meador, Darrell Reneker

Darrell Hyson Reneker

Polymer solutions, containing clay sheets, were electrospun into nanofibers and microfibers that contained clay sheets inside. Controllable removal of polymer by plasma etching from the surface of fibers revealed the arrangement of clay. The shape, flexibility, size distribution and arrangement of clay sheets were observed by transmission and scanning electron microscopy. The clay sheets were partially aligned in big fibers with normal direction of clay sheets perpendicular to fiber axis. Crumpling of clay sheets inside fibers was observed when the fiber diameter was comparable to the lateral size of clay sheets. Single sheets of clay were observed both by catching …


Removal Of Heavy Metals From Mining Impacted Water By An Electrocoagulation-Ultrafiltration Hybrid Process, Long Nghiem, Duminda Kumarasinghe, Liam Pettigrew Dec 2012

Removal Of Heavy Metals From Mining Impacted Water By An Electrocoagulation-Ultrafiltration Hybrid Process, Long Nghiem, Duminda Kumarasinghe, Liam Pettigrew

Long D Nghiem

In this study, the use of an electrocoagulation-ultrafiltration (EC-UF) hybrid system for the treatment of mining impacted wastewater was investigated. A model wastewater solution containing copper, lead, cadmium and other constituents representative of mining impacted wastewater was used in this investigation. The effects of key operational parameters including electrolysis time, current density, and solution pH on the performance of the EC and EC-UF systems were systematically investigated. The removal rates of copper and lead by the EC process were consistently higher than that of cadmium. It is probable that the removal mechanism of cadmium was different from that of the …


Influence Of Feed Water Chemistry On The Removal Of Ionisable And Neutral Trace Organics By A Loose Nanofiltration Membrane, Long Nghiem Dec 2012

Influence Of Feed Water Chemistry On The Removal Of Ionisable And Neutral Trace Organics By A Loose Nanofiltration Membrane, Long Nghiem

Long D Nghiem

This study examined the effects of feed water chemistry and membrane fouling on the rejection of trace organics by a loose nanofiltration membrane. One ionisable and one non-ionisable trace organics were selected for investigation. Results reported here indicate that the solution pH and ionic strength can markedly influence the removal of the ionisable trace organic compound sulfamethoxazole. These observations were explained by electrostatic interactions between the solutes and the membrane surface and by the speciation of the ionisable compound. On the other hand, no appreciable effects of solution pH and ionic strength on the rejection of the neutral compound carbamazepine …


Treatment Of Coal Seam Gas Produced Water For Beneficial Use In Australia: A Review Of Best Practices, Long Nghiem, Ting Ren, Najdat Aziz, Ian Porter, Gyanendra Regmi Dec 2012

Treatment Of Coal Seam Gas Produced Water For Beneficial Use In Australia: A Review Of Best Practices, Long Nghiem, Ting Ren, Najdat Aziz, Ian Porter, Gyanendra Regmi

Long D Nghiem

There has been an exponential increase in both the production and exploration of coal seam gas (CSG) in Australia and many other regions in the world. A major issue associated with the production of CSG is the management of produced water. CSG is usually mixed with water in the coal seam, to recover the gas, the water must be first extracted from the coal seam to reduce pressure. This water — known as co-produced water or CSG water — is typically quite saline, large in volume and may contain heavy metals and other trace elements of concern. The management of …


Critical Risk Points Of Nf/Ro Membrane Filtration Processes In Water Recycling Applications, Long Nghiem, Andrea Schaefer Dec 2012

Critical Risk Points Of Nf/Ro Membrane Filtration Processes In Water Recycling Applications, Long Nghiem, Andrea Schaefer

Long D Nghiem

NF/RO membrane filtration processes have been recognized as an important technology to facilitate water recycling. Those processes are well-proven technologies, which can be used to remove a wide range of contaminants including trace contaminants that are of particular concern in water recycling. However, risk implications in association with brine or concentrate and membrane cleaning wastewater disposal have to date not been adequately understood. This study examines the adsorption and release process of several endocrine-disrupting chemicals (EDCs) during NF/RO filtration processes. Results reported here indicate that the membrane can serve as a large reservoir for EDCs and their release may be …


Removal Of Heavy Metals Form Mining Impacted Water By A Novel Electrocoagulation-Ultrafiltration Hybrid Process, Liam Pettigrew, Long Nghiem, Muttucumaru Sivakumar Dec 2012

Removal Of Heavy Metals Form Mining Impacted Water By A Novel Electrocoagulation-Ultrafiltration Hybrid Process, Liam Pettigrew, Long Nghiem, Muttucumaru Sivakumar

Long D Nghiem

No abstract provided.


Small Town Water Governance In Developing Countries: The Uncertainty Curse, Magnus Moglia, Pascal Perez, Stewart Burn Nov 2012

Small Town Water Governance In Developing Countries: The Uncertainty Curse, Magnus Moglia, Pascal Perez, Stewart Burn

Professor Pascal Perez

lack of consideration of local circumstances and process requirements, and in particular inadequate involvement of affected stakeholders as well as inadequate cross-sectorial coordination. This is not surprising given poor organizational memory combined with decisions being made under time pressure and strict deadlines combined with little adaptive capacity. Additionally, information about the importance of process requirements and engagement is qualitative and as such is unfortunately often given secondary importance. To address this, we suggest a Risk assessment component as part of the project design phase based on Bayesian Networks (BNs) utilizing expert and local knowledge. This not only improves organizational memory …


Participatory Risk Management Approaches For Water Planning And Management: Insights From Australia And Bulgaria, Katherine Daniell, Peter Coad, Irina Ribarova, Ian White, Nils Ferrand, Jean-Emmanuel Rougier, Alexis Tsoukias, Philip Haines, Natalie Jones, Albena Popova, Stewart Burn, Pascal Perez Nov 2012

Participatory Risk Management Approaches For Water Planning And Management: Insights From Australia And Bulgaria, Katherine Daniell, Peter Coad, Irina Ribarova, Ian White, Nils Ferrand, Jean-Emmanuel Rougier, Alexis Tsoukias, Philip Haines, Natalie Jones, Albena Popova, Stewart Burn, Pascal Perez

Professor Pascal Perez

Throughout the world, water management and planning issues are becoming increasingly difficult to handle, and there have been calls for more adapted approaches to aid the decision-making processes required for water planning and management. Participatory risk management approaches appear appropriate for such situations as they can be designed to increase collaboration and manage conflict, explicit uncertainties, andstructure complexity in more understandable forms. This paper will outline some insights and lessons learnt from the design and implementation of two different participatory risk management processes for water governance: avalues-based method based on the Australian and New Zealand Standard for Risk Management for …


Participatory Assessment Of Water Developments In An Atoll Town, Magnus Moglia, Pascal Perez Nov 2012

Participatory Assessment Of Water Developments In An Atoll Town, Magnus Moglia, Pascal Perez

Professor Pascal Perez

Water development projects often fail, which represents a poor outcome given the limited progress against the Millennium Development Goals in providing people with adequate water and sanitation services. This may not be surprising given that water management has been identified as being in the complex system domain. According to the Cynefin framework, many traditional approaches are not suitable; but it suggests an approach based on the methods of probe, sense and respond. In line with this general framework, a participatory assessment methodology has been used to explore experiences in the atoll town of Tarawa in the Republic of Kiribati. After …


Climatic And Human Influences On Water Resources In Low Atolls, Ian White, Tony Falkland, Taboia Metutera, Eita Metai, Pascal Perez, Anne Dray, Marc Overmars Nov 2012

Climatic And Human Influences On Water Resources In Low Atolls, Ian White, Tony Falkland, Taboia Metutera, Eita Metai, Pascal Perez, Anne Dray, Marc Overmars

Professor Pascal Perez

Low, small islands have water supply problems amongst the most critical in the world. Fresh groundwater, the major source of water in many atolls, is vulnerable to natural and human-induced changes. Storm surges, droughts and over-extraction cause seawater intrusion. Settlements and agricultural activities can rapidly pollute shallow groundwaters. Limited land areas restrict freshwater quantities, which are especially vulnerable during frequent ENSO-related droughts. Demand for freshwater is increasing due to population growth and urbanisation. Water use for traditional crops often competes with water supplies for communities. This paper analyses the impact of frequent severe droughts on the quality and quantity of …