129 resultados para 156-949A
Resumo:
The indoline dyes D102, D131, D149, and D205 have been characterized when adsorved on fluorine-doped tin oxide (FTO) and TiO2 electrode surfaces. Adsorption from 50:50 acetonitrile - tert-butanol onto flourine-doped tin oxide (FTO) allows approximate Langmuirian binding constants of 6.5 x 10(4), 2.01 x 10(3), 2.0 x 10(4), and 1.5 x 10(4) mol-1 dm3, respectively, to be determined. Voltammetric data obtained in acetonitrile/0.1 M NBu4PF6 indicate reversible on-electron oxidation at Emid = 0.94, 0.91, 0.88, and 0.88 V vs Ag/AgCI(3 M KCI), respectively, with dye aggregation (at high coverage) causing additional peak features at more positive potentials. Slow chemical degradation processes and electron transfer catalysis for iodine oxidation were observed for all four oxidezed indolinium cations. When adsorbed onto TiO2 nanoparticle films (ca. 9nm particle diameter and ca.3/um thickness of FTO0, reversible voltammetric responses with Emid = 1.08, 1.156, 0.92 and 0.95 V vs Ag/AgCI(3 M KCI), respectively, suggest exceptionally fast hole hopping diffusion (with Dapp > 5 x 10(-9) m2 s-1) for adsorbed layers of four indoline dyes, presumably due to pie-pie stacking in surface aggregates. Slow dye degradation is shown to affect charge transport via electron hopping. Spectrelectrochemical data for the adsorbed indoline dyes on FTO-TiO2 revealed a red-shift of absorption peaks after oxidation and the presence of a strong charge transfer band in the near-IR region. The implications of the indoline dye reactivity and fast hole mobility for solar cell devices are discussed.
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Raman spectroscopy has been used to characterise nine hydrotalcites prepared from aluminate and magnesium solutions (magnesium chloride and seawater). The aluminate hydrotalcites are proposed to have the following formula Mg6Al2(OH)16(CO32-).xH2O, Mg6Al2(OH)16(CO32-,SO42-).xH2O, and Mg6Al2(OH)16(SO42-).xH2O. The synthesis of these hydrotalcites using seawater results in the intercalation of sulfate anions into the hydrotalcite interlayer. The spectra have been used to assess the molecular assembly of the cations and anions in the hydrotalcite structures. The spectra have been conveniently subdivided into spectral features based upon the carbonate anion, the hydroxyl units and water units. This investigation has shown the ideal conditions to form hydrotalcite from aluminate solutions is at pH 14 using magnesium chloride. Changes in synthesis conditions resulted in the formation of impurity products aragonite, thenardite, and gypsum.
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This chapter discusses the experiences of doctoral students who work across traditional disciplinary and university-industry boundaries. These new contexts for doctoral education are shaping how students are experiencing and responding to requirements for changing knowledge relationships. Drawing on Bernstein's discussion of pedagogic practice as being socially constructed, and his conceptual framework outlining the social implications of the weaker boundaries required for these knowledge relationships, we discuss students' descriptions of their topics, processes and challenges and show their strategies for performing scholarly research across these boundaries as key elements in the nature and achievement of “industry readiness”. In particular, we identify two key elements in the pedagogy of industry partnership: students’ understandings and management of the knowledge relationships involved in this work, and the dispositions they bring to bear in negotiating research and careers across disciplinary and sectoral boundaries.
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The interaction of 10-hydroxycamptothecine (HCPT) with DNA under pseudo-physiological conditions (Tris-HCl buffer of pH 7.4), using ethidium bromide (EB) dye as a probe, was investigated with the use of spectrofluorimetry, UV-vis spectrometry and viscosity measurement. The binding constant and binding number for HCPT with DNA were evaluated as (7.1 ± 0.5) × 104 M-1 and 1.1, respectively, by multivariate curve resolution-alternating least squares (MCR-ALS). Moreover, parallel factor analysis (PARAFAC) was applied to resolve the three-way fluorescence data obtained from the interaction system, and the concentration information for the three components of the system at equilibrium was simultaneously obtained. It was found that there was a cooperative interaction between the HCPT-DNA complex and EB, which produced a ternary complex of HCPT-DNA-EB. © 2011 Elsevier B.V.
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We explored the feasibility of community pharmacies for the distribution of chlamydia specimen self-collection kits, which featured a transport medium allowing postage of urine specimens in Australia. Eligible clients were requested to complete a code-matched risk-screening questionnaire in the pharmacy, and the derived risk scores were compared to the test results from the corresponding specimen. Four Queensland pharmacies distributed 156 kits, while 44 questionnaires and 18 specimens were received.
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To date, little is known about the function of gratitude in romantic relationships. Being grateful has been demonstrated to provide a number of positive benefits for individuals; however, few studies have explored how grateful experiences may be beneficial in enhancing romantic relationships. This study explored the extent to which adult attachment moderates the relationship between dispositional gratitude and the experience of intimacy within romantic relationships. A greater disposition toward gratitude was expected to result in more frequent experiences of gratitude. It was also anticipated that experiences of gratitude would be associated with feelings of closeness. Participants (n = 156) were required to be currently in a relationship of at least six months duration and completed a series of questionnaires assessing dispositional gratitude, attachment and emotional intimacy. Moderation analysis revealed that although a positive, weak correlation existed between dispositional gratitude and intimacy, attachment did not moderate this association. It was concluded that further investigation of the experience of gratitude is necessary to understand the function of gratitude in romantic relationships. Methods focusing on specific experiences of gratitude in romantic relationships, and the associated feelings of closeness experienced by each partner, may yield more conclusive findings and may provide support for therapeutic approaches focused on enhancing closeness between couples by increasing experiences of gratitude.
Resumo:
This study proposed that levels of dispositional gratitude influence experiences of intimacy within romantic relationships and that this influence is moderated by relationship attachment. Gratitude, in this study, was described as feelings of appreciation associated with the perception that one had been the focus of another’s intentionally beneficial actions. A greater disposition toward gratitude was expected to result in more frequent experiences of gratitude. It was also anticipated that experiences of gratitude would be associated with feelings of closeness toward the one responsible for the beneficial act. Participants (n=156) ranged in age from 18 – 70 and, although required to be currently in a relationship of at least six months’ duration, each was studied as an individual. Participants included both males and females, in same-sex or other-sex relationships, and completed a series of questionnaires assessing dispositional gratitude, attachment and emotional intimacy. Moderation analysis was conducted using hierarchical regression and revealed that although a positive, weak correlation exists between gratitude and intimacy, attachment did not moderate that association. However, the measures used did not elicit sufficiently divergent responses. Thus neither complete exploration of the proposed association between gratitude and intimacy, nor of the moderation of that association by attachment were possible. In conclusion, further investigation of experiences of gratitude, particularly in relation to enhancing feelings of closeness, is necessary to understand the function of gratitude in romantic relationships. Methods focusing on specific experiences of gratitude in romantic relationships and the associated feelings of closeness experienced by each partner may yield more conclusive findings. In addition, such findings may provide support for therapeutic approaches focused on enhancing closeness between couples by increasing experiences of gratitude.
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Road deposited solids are a mix of pollutants originating from a range of anthropogenic sources common to urban land uses and soil inputs from surrounding areas. These particles accumulate potentially toxic pollutants thereby posing a threat to receiving waters. Reliable estimation of sources of particulate pollutants in build-up and quantification of particle composition is important for the development of best management practices for stormwater quality mitigation. The research study analysed build-up pollutants from sixteen different urban road surfaces and soil from four background locations. The road surfaces were selected from residential, industrial and commercial land uses from four suburbs in Gold Coast, Australia. Collected build-up samples were analysed for solids load, organic matter and mineralogy. The soil samples were analysed for mineralogy. Quantitative and qualitative analysis of mineralogical data, along with multivariate data analysis were employed to identify the relative source contributions to road deposited solids. The build-up load on road surfaces in different suburbs showed significant differences due to the nature of anthropogenic activities, road texture depth and antecedent dry period. Analysis revealed that build-up pollutants consists primarily of soil derived minerals (60%) and the remainder is composed of traffic generated pollutants and organic matter. Major mineral components detected were quartz and potential clay forming minerals such as albite, microline, chlorite and muscovite. An average of 40-50% of build-up pollutants by weight was made up of quartz. Comparison of the mineral component of build-up pollutants with background soil samples indicated that the minerals primarily originate from surrounding soils. About 2.2% of build-up pollutants were organic matter which originates largely from plant matter. Traffic related pollutants which are potentially toxic to the receiving water environment represented about 30% of the build-up pollutants at the study sites.
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This article examines one of the changes implemented in the Corporations Amendment (Insolvency) Act 2007 (Cth) . It is argued that the insertion of s 444DA raises some matters that go to the nature of the insolvency process generally and the operation of Pt 5.3A in a particular. The position of employees in insolvency is a matter that is the subject of much comment from a policy perspective. This article does not cover that debate but provides some initial explanation of the need to protect employees. The second part of the article covers the particular background to the voluntary administration system as far as employee rights are concerned as well as the arguments put forward by the government to justify the change in the legislation which inserted s 444DA . It suggests that there was little evidence provided for the need to protect employee priority rights in this particular way. An alternative explanation is given for the change adopted by the government. The third part of the article suggests that the manner in which the legislation seeks to better protect employee creditors is somewhat clumsy in its operation. It raises a number of questions about how the legislation may operate and argues that given the stated aims, some alteration to it would improve its effectiveness.
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In this this paper I identify specific historical trajectories that are directly contingent upon the deployment and use of new media, but which are actually hidden by a focus on the purely technological. They are: the increasingly abstract and alienated nature of economic value; the subsumption of all labour - material and intellectual - under systemic capital; and the convergence of formerly distinct spheres of analysis –the spheres of production, circulation, and consumption. This paper examines the implications of the knowledge economy from an historical materialist perspective. I synthesise the systemic views of Marx (1846/1972, 1875/1972 1970 1973 1976 1978 1981), Adorno (1951/1974 1964/1973 1991; Horkheimer and Adorno 1944/1998; Jarvis 1998), and Bourdieu (1991 1998) to argue for a language-focused approach to new media research and suggest aspects of Marxist thought which might be useful in researching emergent socio-technical domains. I also identify specific categories in the Marxist tradition which may no longer be analytically useful for researching the effects of new media.
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Many of the classification algorithms developed in the machine learning literature, including the support vector machine and boosting, can be viewed as minimum contrast methods that minimize a convex surrogate of the 0–1 loss function. The convexity makes these algorithms computationally efficient. The use of a surrogate, however, has statistical consequences that must be balanced against the computational virtues of convexity. To study these issues, we provide a general quantitative relationship between the risk as assessed using the 0–1 loss and the risk as assessed using any nonnegative surrogate loss function. We show that this relationship gives nontrivial upper bounds on excess risk under the weakest possible condition on the loss function—that it satisfies a pointwise form of Fisher consistency for classification. The relationship is based on a simple variational transformation of the loss function that is easy to compute in many applications. We also present a refined version of this result in the case of low noise, and show that in this case, strictly convex loss functions lead to faster rates of convergence of the risk than would be implied by standard uniform convergence arguments. Finally, we present applications of our results to the estimation of convergence rates in function classes that are scaled convex hulls of a finite-dimensional base class, with a variety of commonly used loss functions.
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My thesis consists of a creative work plus an exegesis. This exegesis uses case study research to investigate three Brisbane-based media organisations and the role they play in encouraging social inclusion and other positive social change for specific disadvantaged and stigmatised minority groups. Bailey, Cammaerts and Carpentier’s theoretical approach to alternative media forms the basis of this research. Bailey et al. (2008, p. 156) view alternative media organisations as having four important roles, two media-centred and two society-centred, which must all be considered to best understand them: • serving their communities • acting as an alternative to mainstream media discourses • promoting and advocating democratisation in the media and through the media in society • functioning as a crossroads in civil society. The first case study, about community radio station 4RPH (Radio for the Print Handicapped), centres on promoting social inclusion for people with a print disability through access to printed materials (primarily mainstream print media) in an audio format. The station also provides important opportunities for members of this group to produce media and, to a lesser extent, provides disability-specific information and discussions. The second case study, about gay print and online magazine Queensland Pride, focuses on promoting social inclusion and combating the discrimination and repression of people who identify as lesbian, gay, bisexual or transgender. Central issues include the representation (including sexualised representation) of a subculture and niche target market, and the impact of commercialisation on this free publication. The third case study, about community radio station 98.9FM, explores the promotion of social inclusion for peoples whose identity, cultures, issues, politics and contributions are often absent or misrepresented in the mainstream media. This radio station provides “a first level of service” (Meadows & van Vuuren, 1998, p. 104) to these people, but also informs and entertains those in the majority society. The findings of this research suggest that there are two key mechanisms that help these media organisations to effect social change: first, strengthening the minority community and serving its needs, and second, fostering connections with the broader society.