998 resultados para RADICAL ADDITIONS


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"Radical epistemological skepticism" designates the philosophical position that all our beliefs, and knowledge based upon them, are groundless. Skeptics claims have been recorded throughout history and, despite their threat to the security of human knowledge, they endure. The thesis hypothesises that skepticism is a consequence of our development of symbolic capability.

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This study, written from the perspective of a parent activist, articulates the 'battle of ideas' or struggle 'around the truth' of public education in New South Wales since the conservative Greiner government came to power in 1988 and instituted the 'new right' agenda. Political control is theorised in the light of debates about hegemony, power, ideology and truth. Documents what happened in 'consultations' about educational reform between the Ministers and their appointees on on the one hand, and the public education lobby, on the other.

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Investigates the viability of selectively preparing molecules demonstrating the property of left or right "handedness" via free radical reactions. Experimental investigations suggested that a subtle interaction exists between the substituents of an organotin hydride and a target carbon radical during hydrogen atom transfer reactions.

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Very recently 63Cu NMR has been shown to be extremely sensitive in detecting and differentiating between the precipitate phases that form in Al-Cu alloys during heat treatment. This technique is now used to quantify the effectiveness of small additions of Sn to the alloy Al-1.7 at.% Cu in promoting the rapid nucleation and growth of the θ'-phase precipitate. Two parallel series of 63Cu NMR spectra were recorded for Al-1.7 at.% Cu and Al-1.7 at.% Cu-0.01 at.% Sn: (i) aged at 130° C to observe the comparative rate of phase evolution and (ii) aged at 200° C to observe the rate of growth of θ'-phase and to compare with the Vickers hardness of the alloys aged at 200° C for similar periods. Evidence is presented that a metastable precursor phase to θ' (labelled TPHM2757math001) is formed in Al-Cu-Sn which transforms to θ' on further aging.

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An improved post-column 2,2´-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging assay for the screening of antioxidants in complex matrices was developed. Experimental parameters believed to be influential to DPPH• response were studied in a univariate approach. Optimum conditions were found to be: 5×10−5M DPPH• reagent prepared in a 75% methanol: 25% 40mM citric acid–sodium citrate buffer (pH 6) solution, degassed with nitrogen; reaction coil of 2m×0.25mm i.d. PEEK tubing; detection at 521 nm; analysis at room temperature. The analytical utility of this protocol was evaluated by screening for antioxidants in thyme and green tea, in comparison with two commonly employed methodologies.

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This article presents a comparative analysis of Australian and Latin American contemporary poetry which is informed by theories of Eurocentrism derived from contemporary Latin American critical thought.

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pH-detachable poly(styrene) brushes formed on indium−tin oxide (ITO) glass substrates using metal complex chemistry and reversible addition−fragmentation chain transfer (RAFT) polymerization was described. These pH-detachable polymeric brushes were generated using both “graft-from” and “graft-to” methodologies. The methodologies involved either the surface self-assembly of catechol-functional RAFT agents (graft-from) or catechol-terminal polymer chains (graft-to) onto the ITO substrate via titanium−diol coordination. The stepwise functionalization of the ITO glass surfaces was characterized successfully using X-ray photoelectron spectroscopy (XPS) and contact angle measurement. Poly(styrene) brushes generated using the “graft-from” method were denser than those generated using the “graft-to” method, as exemplified by atom force microscopy (AFM) and quantified using cyclic voltammetry. Poly(styrene) brushes assembled using both methods could be detached easily by manipulating the pH of the brush environment. Cyclic voltammetry was utilized to calculate precisely the surface coverage of the RAFT functionality and polymeric brush density.

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Engaging Teachers' makes a deliberate attempt to reclaim the education discourse captured by new right politics and connect it with a radical democratic agenda for schooling. On its agenda are education markets, policy, leadership, professionalism, and communities. Engaging with these is conceived on at least two levels. First, as an invitation to teachers to become involved in reconstructing schooling for socially just purposes and in democratic ways. From this perspective, the politics of engagement is not simply a matter of acquiescence or resistance but is informed by a commitment to generate alternatives: teachers, parents and students making things happen rather than having things done to them. Also signalled is an intent to work collectively, exploring and acting on common interests and across uncommon ground. Second, the book also celebrates teachers engaging in these reconstructive efforts in attractive and meaningful ways. The attraction is decisions about schooling made by those they affect as well as decisions that are meaningful because they engage the interests of all.