Heterogeneous photocatalytic degradation of phenols in wastewater : a review on current status and developments

In recent years, there has been an enormous amount of research and development in the area of heterogeneous photocatalytic water purification process due to its effectiveness in degrading and mineralising the recalcitrant organic compounds as well as the possibility of utilising the solar UV and visible spectrum. One hundred and twenty recently published papers are reviewed and summarised here with the focus being on the photocatalytic oxidation of phenols and their derivatives, predominant in waste water effluent. In this review, the effects of various operating parameters on the photocatalytic degradation of phenols and substituted phenols are presented. Recent findings suggested that different parameters, such as type of photocatalyst and composition, light intensity, initial substrate concentration, amount of catalyst, pH of the reaction medium, ionic components in water, solvent types, oxidising agents/electron acceptors, mode of catalyst application, and calcination temperatures can play an important role on the photocatalytic degradation of phenolic compounds in wastewater. Extensive research has focused on the enhancement of photocatalysis by modification of TiO2 employing metal, non-metal and ion doping. Recent developments in TiO2 photocatalysis for the degradation of various phenols and substituted phenols are also reviewed.

HFL PV micro-inverter with front-end current-fed converter and half-wave cycloconverter

A high-frequency-link micro inverter is proposed with a front-end dual inductor push-pull converter and a grid-connected half-wave cycloconverter. Pulse width modulation is used to control the front-end converter and phase shift modulation is used at the back-end converter to obtain grid synchronized output current. A series resonant circuit and high-frequency transformer are used to interface the front-end and the back-end converters. The operation of the proposed micro-inverter in grid-connected mode is validated using MATLAB/Simpower simulation. Experimental results are provided to further validate the operation.

Current treatment of Helicobacter pylori infection and peptic ulcer disease

Since the initial report by Warren and Marshall in 1984, Helicobacter pylori has assumed an increasingly important role in the pathogenesis of peptic ulcer disease and gastric carcinoma in all ages. A recent National Institutes of Health Consensus Development conference acknowledges the relationship between H. pylori infection and peptic ulcer disease and recommends that the medical community treat H. pylori infection in all patients with Helicobacter pylori and peptic ulcer. Although the same organism, the response to Helicobacter pylori infection in childhood differs somewhat from that seen in adults. The paediatric patient mounts a different inflammatory response, has different macroscopic appearances and has a markedly diminished peptic ulcer disease frequency compared with their adult counterparts. The appearances of antral nodularity appear to be characteristic of Helicobacter pylori infections. The appearances, however, are unrelated to symptoms and the underlying cause for this nodularity remains obscure. Younger children with peptic ulcer diseases are more likely to be Helicobacter pylori negative. This may suggest an increased susceptibility to gastric acid or possibly a very transient Helicobacter pylori infection rather than the well described lifelong infection without treatment. It is well known that the epidemiology of Helicobacter pylori would suggest that the incidence of infection increases with age. There is also geographical variations with the incidence being higher in countries of a third world background. These epidemiological observations fly in the face of all other infections where the major period of acquisition is in childhood. There has been recent evidence to suggest that in fact the incidence in childhood is decreasing in developed countries which could support the observation that there is a decreasing positive serology with successive decades in some countries. It is felt that the most likely mode of transmission of Helicobacter pylori is faecal to oral or oral to oral route. These are similar modes of transmission to Hepatitis A infections. It is obvious that most infections in childhood remain asymptomatic. It is also clear that there is no relationship between chronic recurrent abdominal pain of childhood syndrome and the presence of Helicobacter pylori infections. It remains to be seen as to who should be treated, what with and when. All of these issues will be discussed in the paper.

Critical success factors for positioning Australian business talent in the global knowledge economy : a current research agenda

"Globalisation‟ and the "global knowledge economy‟ have become some of the most common "buzzwords‟ in Australian business, economic, and social sectors in the past decade. Further, knowledge service exports are a growing sector for Australia that utilise complex technical and creative capacities, increasingly rely on virtual work innovations, require new socio-technical systems to establish and maintain effective client relationships in global contexts; and – along with other innovations in the electronic age – may require novel coping abilities on the part of both managers and their employees to achieve desired outcomes (Bandura, 2002). Accordingly, this paper overviews such trends. The paper also includes a research agenda which is a "work-in-progress‟ with a major global company, Shell (Australia); it highlights both the objectives and proposed methodology of the study; it also outlines anticipated key benefits arising from the research.