Determination of sodium oxalate in Bayer liquor using flow-analysis incorporating an anion exchange column and tris(2,2`-bipyridyl)ruthenium(II) chemiluminescence detection

Semi-automated flow injection instrumentation, incorporating a small anion exchange column coupled with tris(2,2′-bipyridyl)ruthenium(II) (Ru(bipy)₃²⁺) chemiluminescence detection, was configured and utilised to develop rapid methodology for the determination of sodium oxalate in Bayer liquors. The elimination of both negative and positive interferences from aluminium(III) and, as yet, unknown concomitant organic species, respectively are discussed. The robustness of the methodology was considerably enhanced by using the temporally stable form of the chemiluminescence reagent, tris(2,2′-bipyridyl)ruthenium(III) perchlorate in dry acetonitrile. Real Bayer process samples were analysed and the results obtained compared well with those performed using standard methods within industrial laboratories.

Enhanced degradation efficiency of toluene using titania/silica photocatalysis as a regeneration process

Three kinds of titania/silica pellets were prepared using the sol-gel method with surface areas of 50.4m² g-1, 421.1m².g^-1 and 89.1m².g^-1. An annular reactor was designed and built to determine the degradation efficiency of toluene and to investigate the relationship between the adsorption and desorption-photocatalytic processes. Surface area is an important factor influencing the adsorption-photocatalytic efficiency. Higher surface areas of pellets contribute to high rates of conversion of toluene. Un-reacted toluene and reaction intermediates accumulating on their surface deactivated the titania/silica catalyst. To overcome this problem, the adsorption and regeneration process were alternated in a dual reactor system. Connecting or disconnecting the toluene feed gas enabled one reactor to adsorb toluene, while the second reactor was regenerated by photocatalysis. Using UV irradiation and titania/silica pellets with high BET surface area (421.1 m².g^-1), the alternating adsorption/regeneration processes kept the degradation efficiency of toluene at 90% after 8 hours operation. By improving the adsorption-photocatalysis efficiency, and minimising the generation and accumulation of intermediate on the surface of pellets, the method extended catalyst life and maintained a high degradation efficiency of toluene.

The role and theoretical evolution of knowledge translation and exchange in public health

Background There is an increased emphasis in public health research on effective models and strategies to support knowledge translation (KT), the exchange, synthesis and ethically sound application of research findings within a complex set of interactions among researchers and knowledge users. In other words, KT can be seen as an acceleration of the knowledge cycle—an acceleration of the natural transformation of knowledge into use (Canadian Institutes of Health Services Research. Knowledge Translation Strategy, 2004). The most recent conceptualizations consider the complexities of public health decision-making. The role of practitioners and communities is increasingly considered.

Methods We identify, describe and discuss the theoretical underpinnings of KT and recommend a way forward to build the evidence for more effective practice.

Results Theoretical perspectives increasingly influence research on KT in public health. A range of innovative work is being conducted to explore methods for KT using practical tools, often with the support of government.

Conclusions KT describes a crucial and to date under-developed element of the research process. There is an important gap in theoretically informed empirical studies of effectiveness of proposed approaches in public health, health promotion and preventive medicine, and thus much of the debate remains abstract. There is clearly an urgent policy need to establish the effectiveness of KT models in a range of contexts. This must include both the consideration of development and the utilization of knowledge.

Computational simulation of gas flow and heat transfer near an immersed object in fluidized beds

To improve the understanding of the heat transfer mechanism and to find a reliable and simple heat-transfer model, the gas flow and heat transfer between fluidized beds and the surfaces of an immersed object is numerically simulated based on a double particle-layer and porous medium model. The velocity field and temperature distribution of the gas and particles are analysed during the heat transfer process. The simulation shows that the change of gas velocity with the distance from immersed surface is consistent with the variation of bed voidage, and is used to validate approximately dimensional analysing result that the gas velocity between immersed surface and particles is 4.6Umf/εmf. The effects of particle size and particle residence time on the thermal penetration depth and the heat-transfer coefficients are also discussed.

Electronic waste exchange for just-in-time building demolition

Waste exchange is as a facilitator for construction and demolition waste deduction by reuse and recycling in construction projects. The just-in-time philosophy, which has been well cultivated in the manufacturing industry, is highly adoptable for demolition projects. Particularly, waste exchange that is usually performed after the actual demolition process can be shifted forward so that waste inventory from demolition is eliminated or reduced to facilitate waste reuse and recycling. A web-based waste exchange system is an ideal platform to enable communications among project participants before a demolition project commences so that waste materials can be sold before they are produced. Therefore, the productivity of the demolition project could be improved. This research paper aims to investigate and analyse the adoption of just-in-time philosophy in building demolition project management. It also describes the development of the proposed web-based waste exchange system that implements just-in-time demolition in detail, including its functionalities, information flows and major components.

Using titania photocatalysts to degrade toluene in a combined adsorption and photocatalysis process

Three types of titania supported materials including titanium dioxide and silicon dioxide composite, titania-coated activated carbon and titania-coated glass beads were prepared and used as photocatalysts to remove toluene from an air stream. Their surface areas were analysed. TEM image reveals titania-silica composites were nanostructured aggregates. XRD was used to determine their crystalline phase which was 100% anatase for the titania component. A fixed bed reactor was designed and built in the laboratory, the toluene with initial concentration of 300 ppm (1149 mg/m³) was fed into the reactor, the destruction efficiencies of toluene were determined by the gas analyser. It was also found that TiO₂-SiO₂ aggregates with high surface area (421.1 m²/g) achieved high destruction efficiencies. The combined effects of adsorption and photocatalysis were further studied by comparing the performance of pure activated carbon (surface area of 932.4 m²/g) and TiO₂ coated activated carbon with BET surface area of 848.4 m²/g. It was found that the TiO₂ coated activated carbon demonstrated comparable results to pure activated carbon, and most importantly, the TiO₂-coated activated carbon can be effectively regenerated by UV irradiation, and was reused as adsorbent. The experimental result of titania-coated glass beads demonstrated a steady degradation efficiency of 15% after a period of 17 hours. It helped to understand that photocatalysis degradation ability of the TiO₂ was constant regardless of the adsorption capacity of the catalysts. This photocatalytic property can be used to degrade the adsorbed toluene and regenerate the catalyst. This study revealed that if the experiments were designed to use adsorption to remove toluene and followed by regeneration of adsorbent using photocatalysis, it could achieve a very high removal efficiency of toluene and reduce the regeneration cost of saturated adsorbent.

Are real exchange rates nonlinear with a unit root? Evidence on PPP for Italy : a note

In this article, we apply the recently developed threshold autoregression model to examine both linearity and stationarity of Italy's real exchange rate vis--vis her six trading partner (G6) countries. Our main finding is that Italy's real exchange rate is a nonlinear process that is not characterized by a unit root process for five of six trading partner countries. This provides strong support for purchasing power parity.

Investigation of Iron (III) desferrioxamine B oxalate ligand exchange by UV-vis spectroscopy: the next step in developing a quantitative analytical method for measuring bioavailable iron in marine ecosystems

To date there are no analytical techniques designed to exclusively measure bioavailable iron in marine environments. The goal of this research is to develop such a technique by isolating the bioavailable iron using the terrestrial siderophore desferrioxamine B (DFB). This project contained many challenging aspects, but the specific goal of this study was to develop a robust analytical technique for quantification of Fe(III)-DFB complexes at nanomolar concentrations. Past work showed that oxalate (Ox) promotes photodissociation of Fe(III)-DFB to Fe(Il), and we are specifically interested in the mechanism of this process. A model was developed using known thermodynamic constants for Fe(III)-DFB and Fe(III) oxalato complexes and adjusting for ionic strength. The model was confirmed by monitoring the UV-VIS absorbance of the system at a variety of oxalate concentrations and pH. The model did not include ternary complexes. Next., the rate of Fe(1I) production during UV irradiation was examined. The results showed that the rate of Fe(II) production was based entirely on the [Fe(Ox)?]3- speciation, and that reoxidation of Fe(II) occurred via reactive oxygen intermediates. This reoxidation could be avoided by either decreasing the oxygen concentration or by adding a Fe(II) stabilizing reagent, such as ferrozine. Further studies need to be done to confirm that these results apply at sub nanomolar concentrations, and the issue of Fe(II) reoxidation at lower Fe concentrations needs to be addressed.

Removal of VOCs by photocatalysis process using adsorption enhanced TiO2–SiO2 catalyst

Volatile organic compounds (VOCs) exist widely in both the indoor and outdoor environment. The main contributing sources of VOCs are motor vehicle exhaust and solvent utilization. Some VOCs are toxic and carcinogenic to human health, such as benzene. In this study, TiO₂–SiO₂ based photocatalysts were synthesized using the sol–gel method, with high surface areas of 274.1–421.1 m²/g obtained. Two types of pellets were used as catalysts in a fixed-bed reactor installed with a UV black light lamp. Experiments were conducted to compare their efficiencies in degrading the VOCs. Toluene was used as the VOC indicator. When the toluene laden gas stream passed through the photocatalytic reactor, the removal efficiencies were determined using a FTIR multi-gas analyser, which was connected to the outlet of the reactor to analyse the toluene concentrations. As the TiO₂–SiO₂ pellets used have a high adsorption capacity, they had dual functions as a photocatalyst and adsorbent in the hybrid photocatalysis and adsorption system. The experiments demonstrated that the porous photocatalyst with very high adsorptive capacity enhanced the subsequent photocatalysis reactions and lead to a positive synergistic effect. The catalyst can be self-regenerated by photocatalytic oxidation of the adsorbed VOCs. When the UV irradiation and feeding gas is continuous, a destruction efficiency of about 25% was achieved over a period of 20 h. Once the system was designed and operated into adsorption/regeneration mode, a higher removal efficiency of about 55% was maintained. It was found that the catalyst pellets with a higher surface area (421 m²/g) achieved higher conversion efficiency (100%) for a longer period than those with a lower surface area. A full spectrum scan was carried out using a Bio-rad Infrared spectrometer, finding that the main components of the treated gas stream leaving the reactor, along with untreated toluene, were CO₂ and water. The suspected intermediates of aliphatic hydrocarbons and CO were found in minimal amounts or were non detectable. The kinetic rate constants were calculated from the experimental results, it appeared that the stronger adsorption capacity, i.e. larger specific surface area, the higher conversion efficiency would be achieved.

The disembodied apprentice : reflections on doctoral exchange

This presentation explores my experience as a full-time on-campus doctoral candidate involved in an international postgraduate exchange. My doctoral work, concerned with the use of networks as a policy mechanism to understand and manage risk for young people, is being completed within an ARC Linkage Project. As such, my doctoral journey is undertaken collaboratively with an industry partner and alongside a community of academics. This stands in contrast to the more common experience of the part-time off-campus Education doctoral candidate largely isolated from an academic community and interacting, to a greater or lesser extent, with only a principal and/or associate supervisor. Lave and Wenger's (1991) theory of legitimate peripheral participation explores the nature of situated learning, moving the focus from the observation and imitation that occurs between the master/apprenticeship to the learning that occurs within the community of which the master forms a part and in which learning occurs as access to practice. The idea of communities of practice is further developed by Wenger (1999) to include both questions of practice, including meaning, community, learning, boundaries and locality and questions of identity including identity in practice, participation, modes of belonging, identification and negotiability. My doctoral process as a disembodied experience of situated learning within a community of practice was highlighted by the opportunity to witness aspects of the academic apprenticeship of higher degree students at the University of Wisconsin-Madison. That comparative experience provides new understandings about the distinctive model of research training that constitutes my academic apprenticeship within Australian higher education.

Dynamic characteristics and efficiency of a fluidized bed heat treatment process

The dynamic characteristics of gas bubbles in fluidized beds are important to determine the heat and mass transfer rates at component surfaces and the treated profiles of components. They also have great impact on the components’ structural, mechanical and physical properties. However, it has been very difficult to monitor those characteristics dynamically. In this paper, a specifically designed fluidized bed was introduced to facilitate the capturing of its dynamic characteristics and a new video image processing and analysis algorithm was developed. The algorithm is robust and adaptive in terms of locating both bubbles and components in beds with a single or multiple components. It has many advantages in dynamic characterization of gas bubbles and monitoring component treatment. By using this algorithm, the properties of gas bubbles over any period of time can be accurately obtained. This technology will provide a potential on-line dynamic monitoring and quality control system for the chemical heat treatment processes with fluidized beds.

Exchange as a determinant in corporate citizenship : exploratory action research into the social construction of corporate citizenship

This study attempts to achieve two things. Firstly it contextualizes corporate citizenship drawing on scholarly, government, media, legal and business discourses which when viewed as a whole, reveals the importance of exchange as a central determinant in how all the major themes or subfields of corporate citizenship function and subsequently become valued within public discourse. Secondly, it reports on exploratory action research where I as a researcher occupied a central role in understanding and contributing towards how organizational settings socially construct and evolve corporate citizenship in real time through various exchange behaviour, drawing from four years field research within BP and its interactions with the external world. This research contributes to new knowledge by building a rare contextual understanding into how cultural change evolves over time within an organization, from its public face, through policy, down into employee and stakeholder reactions, including identifying the crucial role played by Cultural bridges’ in shifting entrenched organizational culture towards embracing new, more sustainable ways of doing business, and additionally how practitioners can legitimately act as a researcher in facilitating this process by assisting an organization to move from simple, transactional relationships to more sustainable integrated social, financial and environmental exchange between business and its broader context. Importantly, this research develops entirely new theoretical models for understanding the social application and commercial value of corporate citizenship to both business and society.

Kurdungurlu got to drive Toyota : differential colonizing process among the Warlpiri

This thesis is based on fieldwork I carried out between December 1987 and June 1989 while living with the residents of a small Warlpiri Outstation Community situated ca. 75 km north-west of Tennant Creek in the Northern Territory of Australia. Colonialism is a process whereby incommensurate gender regimes impact differently on women and men and this is reflected in the indigenous response which affects the socialization of Western things. The notion of the indigenous KIRDA-KURDUNGURLU reciprocity is shown to be consistent with a gender system and to articulate all exchange relations as pro-creative social relationships. This contrasts with the Western capitalist system of production and social reproduction of gendered individuals in that it does not ascribe gender to biological differences between women and men but is derived from a land based social division between Sister-Brother. Social relationships are put under great strain in an effort to socialize Western things for Warlpiri internal use, I argue that the colonization of Aboriginal societies is an ongoing process. Despite the historical shift from a physical all-male frontier to the present day cross-cultural negotiations between Aborigines and Non-Aborigines, men still privilege men. The negotiation process for ownership of a Community Toyota is the most recent phenomenon where this can be observed. Male privilege is established by linking control over the access to the Community Toyota with traditional rights to land. However, the Toyota as Western object has a Western gender identity as well. By pitting women against men it engages people in social conflict which is brought into existence through an organisation of Western concepts based on an alien gender regime. But Western things, especially the Community Toyota, resist socialization because the Warlpiri do not produce these things. Warlpiri people know this and, to satisfy their need for Western things, they engage them in a process of social differentiation. By this process they can be seen actively to maintain the Western system in an effort to maintain themselves as Warlpiri and to secure the production of Western things. This investigation of the cultural response to Western influences shows that indigenous gender relations are only maintained through a socially stressful process of socializing Western things.

Computational simulation of gas flow and heat transfer near immersed object in fluidised bed

To improve the understanding of the heat transfer mechanism and find a reliable and simple heat-transfer model, the gas flow and heat transfer between fluidised beds and immersed object surfaces was numerically simulated based on a double particlelayer and porous medium model. The velocity field and temperature distribution of gas were discussed to analyse the heat transfer process.

Raw materials and process chemical recovery in industrial wastewater pollution control

This article illustrates the different methods employed to recover raw materials and process chemicals in various industries. Although only a few industries such as car painting, metal cutting, electroplating, textile, abattoir and pesticide formulation have been illustrated in case studies, almost all the industries can recover raw materials and process chemicals from their waste streams. The case studies show that the investments on new processes or systems used to recover raw materials and process chemicals have a short payback period and hence bring huge savings to those industries. Thus, each industry should try to recover raw material and process chemicals from waste streams.