999 resultados para 086-2
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We report the Heck coupling of 2-vinyl-4,5-dicyanoimidazole (vinazene) with selected di- and trihalo aromatics in an effort to prepare linear and branched electron-accepting conjugated materials for application in organic electronics. By selecting the suitable halo-aromatic moiety, it is possible to tune the HOMO - LUMO energy levels, absorption, and emission properties for a specific application. In this regard, materials with strong photoluminescence from blue → green → red are reported that may have potential application in organic light-emitting diodes (OLEDs). Furthermore, derivatives with strong absorption in the visible spectrum, coupled with favorable HOMO-LUMO levels, have been used to prepare promising organic photovoltaic devices (OPVs) when combined with commercially available semiconducting donor polymers.
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4-Hexylbithienopyridine has been prepared as a novel electron-accepting monomer for conjugated polymers. To test its electronic properties, alternating copolymers with fluorene and indenofluorene polymers have been prepared. The copolymers displayed reduction potentials about 0.5 V lower than for the corresponding fluorene and indenofluorene homopolymers, indicating much improved electron-accepting properties. Analysis of the microscopic morphology of thin films of the copolymers by AFM shows that they lack the extensive supramolecular order seen with the homopolymers, which is attributed to the bithienopyridine units disrupting the π-stacking. LEDs using these polymers as the emitting layer produce blue-green emission with low turn-on voltages with aluminum electrodes confirming their improved electron affinity. The indenofluorene copolymer displayed an irreversible red shift in emission at high voltages, which is attributed to oxidation of the indenofluorene units. This red shift occurred at higher potentials than for indenofluorene homopolymers in LEDs, suggesting that the heterocyclic moieties offer some protection against electrically promoted oxidation.
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The mineral harmotome (Ba,Na,K)1-2(Si,Al)8O16⋅6H2O is a crystalline sodium calcium silicate which has the potential to be used in plaster boards and other industrial applications. It is a natural zeolite with catalytic potential. Raman bands at 1020 and 1102 cm−1 are assigned to the SiO stretching vibrations of three dimensional siloxane units. Raman bands at 428, 470 and 491 cm−1 are assigned to OSiO bending modes. The broad Raman bands at around 699, 728, 768 cm−1 are attributed to water librational modes. Intense Raman bands in the 3100 to 3800 cm−1 spectral range are assigned to OH stretching vibrations of water in harmotome. Infrared spectra are in harmony with the Raman spectra. A sharp infrared band at 3731 cm−1 is assigned to the OH stretching vibration of SiOH units. Raman spectroscopy with complimentary infrared spectroscopy enables the characterization of the silicate mineral harmotome.
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In this paper, we demonstrate that the distribution of Wolfram classes within a cellular automata rule space in the triangular tessellation is not consistent across different topological general. Using a statistical mechanics approach, cellular automata dynamical classes were approximated for cellular automata defined on genus-0, genus-1 and genus-2 2-manifolds. A distribution-free equality test for empirical distributions was applied to identify cases in which Wolfram classes were distributed differently across topologies. This result implies that global structure and local dynamics contribute to the long term evolution of cellular automata.
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There is a new type of home education parent challenging long-held assumptions about homeschooling (cf. Morton 2012). These parents are well educated (cf. Beck 2010) but have chosen to eschew the social and cultural capital (Bourdieu & Wacquant 1992) of school in favour of some- thing completely different. They are unschoolers, which involves ‘allow- ing children as much freedom to learn in the world as their parents can possibly bear’ (cf. Holt & Farenga 2003: 238). This chapter presents the approach taken by one researcher to explore the reasons families choose unschooling. These families can be difficult to access, because they often fail to register with home education units and thus remain outside the education system (cf. Townsend 2012). Their lack of registration makes them largely invisible, affecting their ability to make an important contribution to debates around education. In spite of this invisibility, many unschoolers are keen to talk to researchers to increase wider understanding of unschooling.
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This tutorial is designed to help new users become familiar with using the Spartan-3E board. The tutorial steps through: writing a small program in VHDL which carries out simple combinational logic; connecting the program inputs and outputs to the switches, buttons and LEDs on the Spartan-3E board; downloading the program to the Spartan-3E board using version 14.7 of the Xilinx ISE; and simulating the program using the iSim Simulator.
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As a writer, teacher and scholar of ‘the knowledge economy’ in the broadest sense, plagiarism fascinates me. I first encountered plagiarism in my Year 12 English class. We had been working for weeks writing poems and had submitted them to our teacher Mr How for assessment. Mr How was generally a pleasant individual who I remember as one of my favourite school teachers; however, he did not suffer fools easily. The time arrived for each of us to read our work to the class. Year 12 poetry being what it usually is, most of our efforts tended to blur into an angsty, slightly pretentious, self-important mess (similar to staff meetings in many university departments). However, one student’s poem stood out. It was emotive, insightful and economical in its use of language … and best of all, it did not suck! The poem’s author was one of the class’ biggest jocks, and not usually one to display such sensitivity, so we were all a little taken aback by what we were hearing. Stunned silence! At the poem’s conclusion, Mr How congratulated the student on such an excellent effort and produced a copy of the collected works of Emily Dickenson (if I remember correctly) from under his desk. He asked the student to turn to a page he had marked and recite the poem printed there. It was, of course, the same one the student had passed off as his. This time, there was no stunned silence: just the sound of remorseful sobs from our jock-poet-plagiarist who had been exposed in front of his classmates.
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Musical work composed by me entitled 2 Cool 4 Skool. One of twelve compositions in this book - the other eleven composed by other composers: Australian Music Examinations Board (AMEB) publication - Alto Saxophone Series 2 Grade 4
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Musical work composed by me entitled 2 Cool 4 Skool. One of twelve compositions in this book - the other eleven composed by other composers: Australian Music Examinations Board (AMEB) publication - Tenor Saxophone Series 2 Grade 4
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Recording for ARIA nominated Film Soundtrack for Spirit of Akasha. Recorded, Mixed, and Co-produced by Phil Graham. Published by Warner Music Australia
An investigation of the validity of the MMPI-2 Response Bias Scale using an analog simulation design