209 resultados para zeolite film


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Modern and Postmodern Los Angeles is examined through the lens of film noir and neo noir. The unique relationship between the city of Los Angeles and cinema is discussed in terms of a historiography emphasizing the role played by these defining film styles and genres. The research draws and extends on the work conducted by Edward Dimendberg, Paula Rabinowitz and Mike Davis, and urban theory approaches associated with the Los Angeles School of Urbanism.

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Zinc oxide (ZnO) is one of the most promising electronic and photonic materials to date. In this work, we present an enhanced ZnO Schottky gas sensor deposited on SiC substrates in comparison to those reported previously in literature. The performance of ZnO/SiC based Schottky thin film gas sensors produced a forward lateral voltage shift of 12.99mV and 111.87mV in response to concentrations of hydrogen gas at 0.06% and 1% in air at optimum temperature of 330 ºC. The maximum change in barrier height was calculated as 37.9 meV for 1% H2 sensing operation at the optimum temperature.

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Vertically-aligned carbon nanotube (VACNT) membranes show very high permeation fluxes due to the inherent smooth and frictionless nature of the interior of the nanotubes. However, the hydrogen selectivities are all in the Knudsen range and are quite low. In this study we grew molecular sieve zeolite imidazolate frameworks (ZIFs) via secondary seeded growth on the VACNT membranes as a gas selective layer. The ZIF layer has a thickness of 5–6 μm and shows good contact with the VACNT membrane surface. The VACNT supported ZIF membrane shows much higher H2 selectivity than Ar (7.0); O2 (13.6); N2 (15.1) and CH4 (9.8). We conclude that tailoring metal–organic frameworks on the membrane surface can be an effective route to improve the gas separation performance of the VACNT membrane.

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Despite the widespread use of paper, plastic or ceramics in dielectric capacitors, water has not been commonly used as a dielectric due to its tendency to become conductive as it easily leaches ions from the environment. We show here that when water is confined between graphene oxide sheets, it can retain its insulating nature and behave as a dielectric. A hydrated graphene oxide film was used as a dielectric spacer to construct a prototype water-dielectric capacitor. The capacitance depends on the water content of the hydrated GO film as well as the voltage applied to the device. Our results show that the capacitance per unit area of the GO film is in the range of 100–800 mF cm �2, which is 5–40 times that of the double layer capacitance per surface area of activated carbon.

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A numerical study is presented to examine the fingering instability of a gravity-driven thin liquid film flowing down the outer wall of a vertical cylinder. The lubrication approximation is employed to derive an evolution equation for the height of the film, which is dependent on a single parameter, the dimensionless cylinder radius. This equation is identified as a special case of that which describes thin film flow down an inclined plane. Fully three-dimensional simulations of the film depict a fingering pattern at the advancing contact line. We find the number of fingers observed in our simulations to be in excellent agreement with experimental observations and a linear stability analysis reported recently by Smolka & SeGall (Phys Fluids 23, 092103 (2011)). As the radius of the cylinder decreases, the modes of perturbation have an increased growth rate, thus increasing cylinder curvature partially acts to encourage the contact line instability. In direct competition with this behaviour, a decrease in cylinder radius means that fewer fingers are able to form around the circumference of the cylinder. Indeed, for a sufficiently small radius, a transition is observed, at which point the contact line is stable to transverse perturbations of all wavenumbers. In this regime, free surface instabilities lead to the development of wave patterns in the axial direction, and the flow features become perfectly analogous to the two-dimensional flow of a thin film down an inverted plane as studied by Lin & Kondic (Phys Fluids 22, 052105 (2010)). Finally, we simulate the flow of a single drop down the outside of the cylinder. Our results show that for drops with low volume, the cylinder curvature has the effect of increasing drop speed and hence promoting the phenomenon of pearling. On the other hand, drops with much larger volume evolve to form single long rivulets with a similar shape to a finger formed in the aforementioned simulations.

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This study surveys and interrogates key conceptual frameworks and artistic practises that flow through the distinct but interconnected traditions of non-narrative film and experimental music, and examines how these are articulated in my own creative sound practise.

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How can teachers reinvigorate content area knowledge and representation through filmmaking? We give examples of what to film, how to film, and why, drawing on our visual ethnographic research with Year 5 students in a working class suburb of Logan, Queensland. The unit developed content knowledge of Indigenous places and practices through sensitising activities in nature. Valuing students’ funds of knowledge, we interpreted local places through epistemologies of different cultures. Through filmmaking workshops by a digital artist, students filmed community members in a local shopping mall about their perceptions of health and happiness in local places. Students were positioned as future community leaders, presenting their films at a national conference. To conclude, we map the dominant and marginalised, local and specialised, and print and visual forms of knowledge that were interwoven, reshaped, and shared through multimodal design.

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We consider a model for thin film flow down the outside and inside of a vertical cylinder. Our focus is to study the effect that the curvature of the cylinder has on the gravity-driven instability of the advancing contact line and to simulate the resulting fingering patterns that form due to this instability. The governing partial differential equation is fourth order with a nonlinear degenerate diffusion term that represents the stabilising effect of surface tension. We present numerical solutions obtained by implementing an efficient alternating direction implicit scheme. When compared to the problem of flow down a vertical plane, we find that increasing substrate curvature tends to increase the fingering instability for flow down the outside of the cylinder, whereas flow down the inside of the cylinder substrate curvature has the opposite effect. Further, we demonstrate the existence of nontrivial travelling wave solutions which describe fingering patterns that propagate down the inside of a cylinder at constant speed without changing form. These solutions are perfectly analogous to those found previously for thin film flow down an inclined plane.

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The Australian Curriculum: English, v.5 (ACARA, 2013) now being implemented in Queensland asks teachers and curriculum designers to incorporate the cross curriculum priority (CCP)of Indigenous issues through Aboriginal and Torres Strait Islander histories and cultures. In the Australian Curriculum English, (AC:E) one way to address this CCP is by including texts by and about Aboriginal and Torres Strait Islander people. With the rise of promising and accomplished young, Indigenous filmmakers such as Ivan Sen, Rachael Perkins, Wayne Blair and Warwick Thornton, this guide focuses on the suitable films for schools implementing the Australian Curriculum in terms of cultural representations. This annotated guide suggests some films suitable for inclusion in classroom study and suggests some companion texts (novels, plays, television series and animations, documentaries, poetry and short stories) that may be studied alongside the films. Some of these are by Indigenous filmmakers and writers, and others features Aboriginal and Torres Strait Island representations in character and/or themes.

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In this paper, we report the preparation and characterisation of nanometer-sized TiO2, CdO, and ZnO semiconductor particles trapped in zeolite NaY. Preparation of these particles was carried out via the traditional ion exchange method and subsequent calcination procedure. It was found that the smaller cations, i.e., Cd2+ and Zn2+ could be readily introduced into the SI′ and SII′ sites located in the sodalite cages, through ion exchange; while this is not the case for the larger Ti species, i.e., Ti monomer [TiO]2+ or dimer [Ti2O3]2+ which were predominantly dispersed on the external surface of zeolite NaY. The subsequent calcination procedure promoted these Ti species to migrate into the internal surface of the supercages. These semiconductor particles confined in NaY zeolite host exhibited a significant blue shift in the UV-VIS absorption spectra, in contrast to the respective bulk semiconductor materials, due to the quantum size effect (QSE). The particle sizes calculated from the UV-VIS optical absorption spectra using the effective mass approximation model are in good agreement with the atomic absorption data.

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The reaction of pyrrole and thiophene monomers with copper- or nickel-exchanged mordenite has been investigated using X-ray photoelectron (XPS) and photoacoustic infrared (PAIRS) spectroscopies. Because of the differing oxidising powers of the cations studied, polymerisation occurred only with copper-exchanged mordenite. PAIRS and XPS data indicated that both polypyrrole and polythiophene were partially oxidised when synthesised within the zeolite structure. IR spectra of polythiophene and polythiophene and polypyrrole showed intense bands typical of ring vibrations which could couple to the large dipole change induced by charges moving along the polythiophene chain. In addition it was noted that only vibrations typical of oxidised polymer structures were recorded, suggesting that the charge carrier was located within these segments. Furthermore, N 1s spectra contained a high binding energy peak at 402.5 eV which was attributed to a positively charged nitrogen species, in agreement with IR data. Significantly, C 1s spectra confirmed that molecular wires were formed within the confines of the zeolite lattice. Depth-profiling experiments suggested that polypyrrole was distributed throughout the entire zeolite host. By contrast, polythiophene may have been restricted to the uppermost zeolite channels owing to the ability of sulfur species to bond to CuI sites [produced by reduction of copper(II) ions during the polymerisation process], thus obstructing movement along the channels.

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In the years since the release of the film Field of Dreams, the phrase “If you build it, they will come” has become a cliché beloved by journalists, boosters of speculative land developments or remediations and misty-eyed enthusiasts of a host of unlikely schemes. It is one of the articles of faith of the location interest, the coalition of actors motivated to work to attract film business to a particular place. The phrase is full of optimism and potential. It seeks to instill confidence that the construction of production infrastructure like studios and the nourishment of conditions for local service providers will drive the (economic) locomotive and open the (celebrity) stargate. Unfortunately sometimes, it is just a crazy dream.

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Objective: Theaflavin (TF) from the black tea can react to human salivary proline-rich proteins (PRPs) to form stains on exposed dental surfaces. Here, we employed a model of protein/pigment film using TF and dephosphorylated bovine b-casein (Db-CN), which has an extended conformation, similar to that of salivary PRPs, on a sensor surface to assess the efficacy of cysteine proteases (CPs) including papain, stem bromelain, and ficin, on removing TF bound to Db-CN and the control TF readsorption on the residual substrate surfaces was also measured. Methods: The protein/pigment complex film was built by using a quartz crystal microbalance with dissipation (QCM-D). The efficacies of CPs were assessed by Boltzman equation model. The surface details were detected by grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles. Results: The efficacy order of CPs on hydrolyzing protein/pigment complex film is ficin > papain > bromelain. The results from grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles demonstrated that TF bound on the Db- CN was effectively removed by the CPs, and the amount of TF readsorption on both the residual film of the Db-CN/TF and the Db-CN was markedly decreased after hydrolysis. Conclusion: This study indicates the potential application of the CPs for tooth stain removal and suggests that these enzymes are worthy of further investigation for use in oral healthcare.

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Thin film supercapacitors are produced by using electrochemically exfoliated graphene (G) and wet-chemically produced graphene oxide (GO). Either G/GO/G stacked film or sole GO film are sandwiched by two Au films to make devices, where GO is the dielectric spacer. The addition of graphene film for charge storage can increase the capacitance about two times, compared to the simple Au electrode. It is found that the GO film has very high dielectric constant, accounting for the high capacitance of these devices. AC measurements reveal that the relative permittivity of GO is in the order of 104 within the frequency range of 0.1–70 Hz.