Avaliação das condições de precipitação do azul da Prússia sobre pó de grafite visando o desenvolvimento de eletrodos de pasta de carbono para a quantificação de nitrito

An amperometric FIA method for nitrite quantification based on nitrite electroreduction and employing a carbon paste electrode (CPE) chemically modified with iron hexacyanoferrate (HCF) as an amperometric detector was developed. The influence of experimental conditions on the preparation of the electrode materials was evaluated and the materials obtained in each study were used for the development of modified electrodes. The electrochemical sensors were prepared by a fast, simple, and inexpensive procedure, and the long-term performance of the electrodes were quite satisfactory as the stability was maintained over one year. HCF was an effective redox mediator for nitrite electroreduction in acidic media, allowing nitrite detection at +0.2 V vs. Ag/AgClsat, which is a potential free of possible interfering species that are normally present in food and water samples. The electrochemical cell used in the FIA system was similar to a batch injection analysis cell, enabling recirculation of the carrier solution. This is an attractive feature because it allows the use of a high flow rate (6 mL min-1) leading to high sensitivity and analysis speed, while keeping reagent consumption low. The proposed method had a detection limit of 9 μmol L-1 and was successfully employed for nitrite quantification in spiked water and sausage samples. The obtained results were in good agreement with those provided by the spectrophotometric official method. At a 95 % confidence level it was not observed statistical differences neither in nitrite content nor in the precision provided by both methods. The experimental conditions for the synthesis of HCF were optimized and the best electrode material was prepared by mixing FeCl3, K4[Fe(CN)6] and carbon powder subjected to an acid and thermal treatment (400 ºC), followed by ultrasonic agitation at 4 °C. This material was used to construct an electrode with improved analytical performance to reduce nitrite, which presented greater stability compared to HCF film electrodeposited on the EPC, showing that the preparation procedure of the electrode material is an effective strategy for the development of HCF modified electrodes.

Aluminum and iron can be deposited in the calcified matrix of bone exostoses.

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Synthesis and characterization of low-cost materials for aqueous Na-ion batteries

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The big blue

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.

Synthesis, characterization of palygorskite supported zero-valent iron and its application for methylene blue adsorption

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.

Synchronous fluorescence and UV–vis spectroscopic studies of interactions between the tetracycline antibiotic, aluminium ions and DNA with the aid of the Methylene Blue dye probe

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.

Motivating blue-collar employees : a case study of the Chinese workforce

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.

Development of a workplace wellness promotion pilot framework : a case study of the Blue Care Staff Wellness Program

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.

Marking the liminal for true blue Aussies : the generic placement of Aboriginality in Australian soap operas.

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.

The motivation and structure of corrupt police networks : theorising the dark side of the ‘thin blue line’

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.

Deep Blue Orchestra

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.

Validation of a food behavior questionnaire for male blue collar workers

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.

Between the Devil and the Deep-blue Sea: Conceptualizing Victims Experiences of Policing in Domestic Violence in the Singaporean Context

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.