29 resultados para Methylene Blue
em Queensland University of Technology - ePrints Archive
Resumo:
In this work, natural palygorskite impregnated with zero-valent iron (ZVI) was prepared and characterised. The combination of ZVI particles on surface of fibrous palygorskite can help to overcome the disadvantage of ultra-fine powders which may have strong tendency to agglomerate into larger particles, resulting in an adverse effect on both effective surface area and catalyst performance. There is a significant increase of methylene blue (MB) decolourized efficiency on acid treated palygorskite with ZVI grafted, within 5 mins, the concentration of MB in the solution was decreased from 94 mg/L to around 20 mg/L and the equilibration was reached at about 30 to 60 mins with only around 10 mg/L MB remained in solution. Changes in the surface and structure of prepared materials were characterized using X-ray diffraction (XRD), infrared (IR) spectroscopy, surface analysing and scanning electron microscopy (SEM) with element analysis and mapping. Comparing with zero-valent iron and palygorskite, the presence of zero-valent iron reactive species on the palygorskite surface strongly increases the decolourization capacity for methylene blue, and it is significant for providing novel modified clay catalyst materials for the removal of organic contaminants from waste water.
Resumo:
Synchronous fluorescence spectroscopy (SFS) was applied for the investigation of interactions of the antibiotic, tetracycline (TC), with DNA in the presence of aluminium ions (Al3+). The study was facilitated by the use of the Methylene Blue (MB) dye probe, and the interpretation of the spectral data with the aid of the chemometrics method, parallel factor analysis (PARAFAC). Three-way synchronous fluorescence analysis extracted the important optimum constant wavelength differences, Δλ, and showed that for the TC–Al3+–DNA, TC–Al3+ and MB dye systems, the associated Δλ values were different (Δλ = 80, 75 and 30 nm, respectively). Subsequent PARAFAC analysis demonstrated the extraction of the equilibrium concentration profiles for the TC–Al3+, TC–Al3+–DNA and MB probe systems. This information is unobtainable by conventional means of data interpretation. The results indicated that the MB dye interacted with the TC–Al3+–DNA surface complex, presumably via a reaction intermediate, TC–Al3+–DNA–MB, leading to the displacement of the TC–Al3+ by the incoming MB dye probe.
Resumo:
Filtration membrane technology has already been employed to remove various organic effluents produced from the textile, paper, plastic, leather, food and mineral processing industries. To improve membrane efficiency and alleviate membrane fouling, an integrated approach is adopted that combines membrane filtration and photocatalysis technology. In this study, alumina nanofiber (AF) membranes with pore size of about 10 nm (determined by the liquid-liquid displacement method) have been synthesized through an in situ hydrothermal reaction, which permitted a large flux and achieved high selectivity. Silver nanoparticles (Ag NPs) are subsequently doped on the nanofibers of the membranes. Silver nanoparticles can strongly absorb visible light due to the surface plasmon resonance (SPR) effect, and thus induce photocatalytic degradation of organic dyes, including anionic, cationic and neutral dyes, under visible light irradiation. In this integrated system, the dyes are retained on the membrane surface, their concentration in the vicinity of the Ag NPs are high and thus can be efficiently decomposed. Meanwhile, the usual flux deterioration caused by the accumulation of the filtered dyes in the passage pores can be avoided. For example, when an aqueous solution containing methylene blue is processed using an integrated membrane, a large flux of 200 L m-2 h-1 and a stable permeating selectivity of 85% were achieved. The combined photocatalysis and filtration function leads to superior performance of the integrated membranes, which have a potential to be used for the removal of organic pollutants in drinking water.
Resumo:
Adsorptions of Rhodamine B (RhB) and Basic Blue 9 (BB9, also known as methylene blue) by sugarcane bagasse of different surface areas were compared in this study. There was a small gain in the amount of dye removed by increasing bagasse surface area from 0.57 m2/g to 1.81 m2/g. BB9 adsorption was less sensitive to surface area change than RhB adsorption. Adsorption capacity of 250 mg/L RhB on 1 g/L bagasse was 65.5 mg/g compared to a value of 30.7 mg/g obtained with BB9 under the same conditions. Increasing adsorption temperature (from 30 °C to 50 °C) while having no effect on RhB adsorption, slightly decreased BB9 adsorption by ~4%. The differences in adsorption performances between these dyes have been related to the molecular structure of the dyes and the surface chemistry of bagasse.
Resumo:
For the 1.5 million travellers who annually visit the Blue Mountains to experience the Australian Bush, it just got closer. The Echo Point redevelopment by Tract Consultants is a megastructure in the void.
Resumo:
The Katz and Kahn (1978) motivational framework is an open system management theory that underscores the importance of self-regulation while stressing the significance of using continuous feedback to adapt in a rapidly changing environment. This study aims to examine Katz and Kahn’s prepositions that the implementation of a system of rule compliance, external rewards, and internalized motivation can decrease employee turnover, increase quantitative and qualitative standards of performance, and enhance cooperation and creativeness. The results among 233 Chinese employees (96.6% response rate) indicated partial support for Katz and Kahn’s motivational framework. The implication for improving the Chinese workforce, in particular blue-collar occupations, is discussed.
Resumo:
Workplace wellness initiatives are currently unreflective of the multidimensional and holistic nature of the wellness construct. There exists an opportunity for promoters of health to move toward models of workplace wellness promotion that more fully appreciate the interconnected nature of health dimensions and promote them even-handedly. The Blue Care Staff Wellness Program framework was developed in response to a recognised need for consistent and wellness-focused constructs for workplace wellness promotion and dissemination. The framework promotes and supports the individual and organisational wellness of the Blue Care employee population by providing a comprehensive and sustainable employee wellness program. This has been achieved by the adoption of consistent wellness principles to guide the framework conception and theory based development. The use of the framework in a pilot program will provide insight into the frameworks effectiveness in promoting a comprehensive workplace wellness program, and go further to establish the relationship between wellness and productivity in the workplace.
Resumo:
This paper addresses a previously unconsidered history — that of Aboriginal characters in Australian soap operas. Rejecting critical approaches which have obtained even into the 1990s, it refuses to judge these characters as 'good' or 'bad' manifestations of indigeneity. Rather, using the idea that genre is a way of closing down interpretive possibilities, the paper looks at the manner in which generic expectations around soap operas produce particular valences for these representations of Aboriginality. It points to the many ways in which these indigenous characters are insistently constructed as liminal in soap operas' structural communities - simultaneously inside and outside of the group. This is seen to accord with the suggestions of Jakubowicz et al about the ways in which Aboriginal people are positioned by wider social discourses.
Resumo:
In recent times considerable research attention has been directed to understanding dark networks, especially criminal and terrorist networks. Dark networks are those in which member motivations are self rather than public interested, achievements come at the cost of other individuals, groups or societies and, in addition, their activities are both ‘covert and illegal’ (Raab & Milward, 2003: 415). This ‘darkness’ has implications for the way in which these networks are structured, the strategies adopted and their recruitment methods. Such entities exhibit distinctive operating characteristics including most notably the tension between creating an efficient network structure while retaining the ability to hide from public view while avoiding catastrophic collapse should one member cooperate with authorities (Bouchard 2007). While theoretical emphasis has been on criminal and terrorist networks, recent work has demonstrated that corrupt police networks exhibit some distinctive characteristics. In particular, these entities operate within the shadows of a host organisation - the Police Force and distort the functioning of the ‘Thin Blue Line’ as the interface between the law abiding citizenry and the criminal society. Drawing on data derived from the Queensland Fitzgerald Commission of Enquiry into Police Misconduct and related documents, this paper examines the motivations, structural properties and operational practices of corrupt police networks and compares and contrasts these with other dark networks with ‘bright’ public service networks. The paper confirms the structural differences between dark corrupt police networks and bright networks and suggests. However, structural embeddedness alone is found to be an insufficient theoretical explanation for member involvement in networks and that a set of elements combine to impact decision-making. Although offering important insights into network participation, the paper’s findings are especially pertinent in identifying additional points of intervention for police corruption networks.
Resumo:
Under an Australian Research Council Linkage Grant, the partnering research organisations QUT, Creative Media Warehouse, The Brisbane Festival and The Queensland Orchestra undertook extensive reviews of many aspects of traditional and contemporary arts practice. We will publish excerpts from the findings soon. deepblue is committed to ongoing research as a part of the day to day operation and is currently working in partnership with John Kotzas and the team at QPAC on exploring new techniques for presenting and marketing deep blue.
Resumo:
During nutrition intervention programs, some form of dietary assessment is usually necessary. This dietary assessment can be for: initial screening; development of appropriate programs and activities; or, evaluation. Established methods of dietary assessment are not always practical, nor cost effective in such interventions, therefore an abbreviated dietary assessment tool is needed. The Queensland Nutrition Project developed such a tool for male Blue Collar Workers, the Food Behaviour Questionnaire, consisting of 27 food behaviour related questions. This tool has been validated in a sample of 23 men, through full dietary assessment obtained via food frequency questionnaires and 24 hour dietary recalls. Those questions which correlated poorly with the full dietary assessment were deleted from the tool. In all, 13 questions was all that was required to distinguish between high and low dietary intakes of particular nutrients. Three questions when combined had correlations with refined sugar between 0.617 and 0.730 (p<0.005); four questions when combined had correlations with dietary fibre as percentage of energy of 0.45 (p<0.05); five questions when combined had a correlation with total fat of 0.499 (p<0.05); and, 4 questions when combined had a correlation with saturated fat of between 0.451 and 0.589 (p<0.05). A significant correlation could not be found for food behaviour questions with respect to dietary sodium. Correlations for fat as a function of energy could not be found.
Resumo:
In contextualising victims' experiences of policing in domestic violence situations in Singapore, two extreme but interrelated sets of responses have been observed. At one end of the continuum, criminal justice sanctions are strictly contingent upon victim willingness to initiate criminal proceedings against the perpetrator, and at the other, victims' rights, needs and preferences seem to be usurped by the justice system regardless of victims' choice. Neither of these positions takes victims' interests into account. Nor do they stem from an understanding of the sociocultural, economic and structural circumstances in which victims experienced violence, and continued to experience it, long after a police intervention. Data from the research revealed that criminalisation as an ideological and legally practical tool was not only rendered ineffective but irrelevant to the experiences of women in the Singaporean context.Two factors account for this phenomenon. First, the absence of support structures to achieve criminalisation and address victims' needs in the aftermath of criminalisation; second, the authoritative, paternalistic and patriarchal state impedes processes aimed at the empowerment of women victims.