title: Synergistic electric field enhancement of the effectiveness of chlorine species formed during electrochemical disinfection of drinking water

authors: Nath, Hilary

subjects: Electro-disinfection

abstract: In line in situ electrochemical disinfection of drinking water with chloride concentrations as low as 10 mg/L has been demonstrated at practical flow rates of at least 3 m3/day using a novel perforated electrode flow through (PEFT) cell with a 50 μm inter-electrode gap. Sufficient chlorine to achieve 6 log inactivation of Escherichia coli bacteria was produced at applied voltages as low as 5 V and with energy consumptions as low as 0.5 kWh/m3. At slightly higher applied voltages, the specific lethality of electrochemically produced chlorine was enhanced by at least two orders of magnitude to greater than 50 L/mg min. This dramatically enhanced lethality is consistent with a synergistic effect resulting from reversible electroporation when electric fields greater than 1.3 kV/cm are produced. There was no evidence for involvement of other species such as reactive oxygen species (ROSs). Disinfection of drinking water using the PEFT cell is cost competitive with other disinfection technologies and when enhanced by the electric field is much less likely to produce disinfection by products.

text: Synergistic electric field enhancement of the effectiveness of chlorine species formed during electrochemical disinfection of drinking water In line in situ electrochemical disinfection of drinking water with chloride concentrations as low as 10 mg/L has been demonstrated at practical flow rates of at least 3 m3/day using a novel perforated electrode flow through (PEFT) cell with a 50 μm inter-electrode gap. Sufficient chlorine to achieve 6 log inactivation of Escherichia coli bacteria was produced at applied voltages as low as 5 V and with energy consumptions as low as 0.5 kWh/m3. At slightly higher applied voltages, the specific lethality of electrochemically produced chlorine was enhanced by at least two orders of magnitude to greater than 50 L/mg min. This dramatically enhanced lethality is consistent with a synergistic effect resulting from reversible electroporation when electric fields greater than 1.3 kV/cm are produced. There was no evidence for involvement of other species such as reactive oxygen species (ROSs). Disinfection of drinking water using the PEFT cell is cost competitive with other disinfection technologies and when enhanced by the electric field is much less likely to produce disinfection by products.

year: 2012

title: Keeping pace with technology: drones, disturbance and policy deficiency

authors: Wallace, Philippa Jane

subjects: UAV

abstract: This paper analyses regulatory responses to rapid intensiﬁcation of the use of drones/remotely piloted aircraft (RPA) in the context of wildlife protection. Beneﬁts and disadvantages of the technology to wildlife are examined, before three key limitations in policy and law are identiﬁed: failure to address wildlife disturbance in RPA regulation; reliance upon insufﬁciently comprehensive existing wildlife protection legislation to manage disturbance effects; and limited species-speciﬁc research on disturbance. A New Zealand case study further reveals an inconsistent regulatory approach struggling to keep pace with innovation, inadequate regulatory capture of environmental effects due to exemption as “aircraft”, and no recognition that speciﬁc geographical locations, such as coastal areas, distinguished by recreational pressures and high numbers of threatened species require special consideration. Recommendations include acknowledging the impact on wildlife in policy, gap analysis of legal arrangements for protection from disturbance (including airspace), and adoption of minimum approach distances to threatened species.

text: Keeping pace with technology: drones, disturbance and policy deficiency This paper analyses regulatory responses to rapid intensiﬁcation of the use of drones/remotely piloted aircraft (RPA) in the context of wildlife protection. Beneﬁts and disadvantages of the technology to wildlife are examined, before three key limitations in policy and law are identiﬁed: failure to address wildlife disturbance in RPA regulation; reliance upon insufﬁciently comprehensive existing wildlife protection legislation to manage disturbance effects; and limited species-speciﬁc research on disturbance. A New Zealand case study further reveals an inconsistent regulatory approach struggling to keep pace with innovation, inadequate regulatory capture of environmental effects due to exemption as “aircraft”, and no recognition that speciﬁc geographical locations, such as coastal areas, distinguished by recreational pressures and high numbers of threatened species require special consideration. Recommendations include acknowledging the impact on wildlife in policy, gap analysis of legal arrangements for protection from disturbance (including airspace), and adoption of minimum approach distances to threatened species.

year: 2017

title: The rhetorical organization of discourse: language revitalisation and the question of authenticity

authors: Crombie, Winifred

subjects: Te reo Māori

abstract: We propose here one approach to unravelling some aspects of authentic discourse construction in a way that may prove useful to teachers and learners of Māori. The approach is illustrated in relation to one text which realises the argument genre in Māori. In terms of text-type, the example provided is an open letter of advice/warning. The approach illustrated here, and the hypotheses emerging from it, are currently being further tested by one of the authors with reference to a corpus of written texts.

text: The rhetorical organization of discourse: language revitalisation and the question of authenticity We propose here one approach to unravelling some aspects of authentic discourse construction in a way that may prove useful to teachers and learners of Māori. The approach is illustrated in relation to one text which realises the argument genre in Māori. In terms of text-type, the example provided is an open letter of advice/warning. The approach illustrated here, and the hypotheses emerging from it, are currently being further tested by one of the authors with reference to a corpus of written texts.

year: 2000-11-24