228 resultados para FILM ELECTRODE


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As solar hydrogen is a sustainable and environmental friendly energy carrier, it is considered to take the place of fossil fuels in the near future. Solar hydrogen can be generated by splitting of water under solar light illumination. In this study, the use of nanostructured hematite thin-film electrodes in photocatalytic water splitting was investigated. Hematite (á-Fe2O3) has a narrow band-gap of 2.2 eV, which is able to utilise approximately 40% of solar radiation. However, poor photoelectrochemical performance is observed for hematite due to low electrical conductivity and a high rate of electron-hole recombination. An extensive review of useful measures taken to overcoming the disadvantages of hematite so as to enhance its performance was presented including thin-film structure, nanostructuring, doping, etc. Since semiconductoring materials which exhibit an inverse opal structure are expected to have a high surface-volume ratio, unique optical characteristics and a shorter distance for photogenerated holes to travel to the electrode/electrolyte interface, inverse opals of hematite thin films deposited on FTO glass substrate were successfully prepared by doctor blading using PMMA as a template. However, due to the poor adhesion of the films, an acidic medium (i.e., 2 M HCl) was employed to significantly enhance the adhesion of the films, which completely destroyed the inverse opal structure. Therefore, undoped, Ti and Zn-doped hematite thin films deposied on FTO glass substrate without an inverse opal structure were prepared by doctor blading and spray pyrolysis and characterised using SEM, EDX, XRD, TGA, UV-Vis spectroscopy and photoelectrochemical measurements. Regarding the doped hematite thin films prepared by doctor blading, the photoelectrochemical activity of the hematite photoelectrodes was improved by incorporation of Ti, most likely owing to the increased electrical conductivity of the films, the stabilisation of oxygen vacancies by Ti4+ ions and the increased electric field of the space charge layer. A highest photoresponse was recorded in case of 2.5 at.% Ti which seemed to be an optimal concentration. The effect of doping content, thickness, and calcination temperature on the performance of the Ti-doped photoelectrodes was investigated. Also, the photoactivity of the 2.5 at.% Ti-doped samples was examined in two different types of electrochemical cells. Zn doping did not enhance the photoactivity of the hematite thin films though Zn seemed to enhance the hole transport due to the slow hole mobility of hematite which could not be overcome by the enhancement. The poor performance was also obtained for the Ti-doped samples prepared by spray pyrolysis, which appeared to be a result of introduction of impurities from the metallic parts of the spray gun in an acidic medium. Further characterisation of the thin-film electrodes is required to explain the mechanism by which enhanced performance was obtained for Ti-doped electrodes (doctor blading) and poor photoactivity for Zn and Ti-doped samples which were synthesised by doctor blading and spray pyrolysis, respectively. Ti-doped hematite thin films will be synthesised in another way, such as dip coating so as to maintain an inverse opal structure as well as well adhesion. Also, a comparative study of the films will be carried out.

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For almost a decade before Hollywood existed, French firm Pathe towered over the early film industry with estimates of its share of all films sold around the world varying between 50-70%. Pathe was the first global entertainment company. This paper analyses its rise to market leadership by applying a theoretical framework drawn from the business literature on causes of industry dominance, which provides insights into how firms acquire and maintain market dominance, and in this case the film industry. This paper uses evidence presented by film historians to argue that Pathe “fits” the expected theoretical model of a dominant firm because it had a marketing orientation, used an effective quality-based competitive strategy and possessed the six critical strategic marketing capabilities that business research shows enable the best performing firms to consistently outperform rivals

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In November 2010, the world watched as 33 Chilean miners were rescued from the depths of the earth where they had been stranded since July. We were able to watch because the world’s news media were there, drawn by the human drama, the suspense, the spectacle. It was a great news story, ideally suited for the 24-hour news culture we live in today, and the globalised audience that consumes it. Nothing much happened for 68 of those 69 days, until that final 24 hours when the miners emerged. But we were transfixed, engrossed, immersed in the story.

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Solar ultraviolet (UV) radiation causes a range of skin disorders as well as affecting vision and the immune system. It also inhibits development of plants and animals. UV radiation monitoring is used routinely in some locations in order to alert the population to harmful solar radiation levels. There is ongoing research to develop UV-selective-sensors [1–3]. A personal, inexpensive and simple UV-selective-sensor would be desirable to measure UV intensity exposure. A prototype of such a detector has been developed and evaluated in our laboratory. It comprises a sealed two-electrode photoelectrochemical cell (PEC) based on nanocrystalline TiO2. This abundant semiconducting oxide, which is innocuous and very sta-ble, is the subject of intense study at present due to its application in dye sensitized solar cells (DSSC) [4]. Since TiO2 has a wide band gap (EG = 3.0 eV for rutile and EG = 3.2 eV for anatase), it is inher-ently UV-selective, so that UV filters are not required. This further reduces the cost of the proposed photodetector in comparison with conventional silicon detectors. The PEC is a semiconductor–electrolyte device that generates a photovoltage when it is illuminated and a corresponding photocur-rent if the external circuit is closed. The device does not require external bias, and the short circuit current is generally a linear function of illumination intensity. This greatly simplifies the elec-trical circuit needed when using the PEC as a photodetector. DSSC technology, which is based on a PEC containing nanocrystalline TiO2 sensitized with a ruthenium dye, holds out the promise of solar cells that are significantly cheaper than traditional silicon solar cells. The UV-sensor proposed in this paper relies on the cre-ation of electron–hole pairs in the TiO2 by UV radiation, so that it would be even cheaper than a DSSC since no sensitizer dye is needed. Although TiO2 has been reported as a suitable material for UV sensing [3], to the best of our knowledge, the PEC configuration described in the present paper is a new approach. In the present study, a novel double-layer TiO2 structure has been investigated. Fabrication is based on a simple and inexpensive technique for nanostructured TiO2 deposition using microwave-activated chemical bath deposition (MW-CBD) that has been reported recently [5]. The highly transparent TiO2 (anatase) films obtained are densely packed, and they adhere very well to the transparent oxide (TCO) substrate [6]. These compact layers have been studied as contacting layers in double-layer TiO2 structures for DSSC since improvement of electron extraction at the TiO2–TCO interface is expected [7]. Here we compare devices incorporating a single mesoporous nanocrystalline TiO2 structure with devices based on a double structure in which a MW-CBD film is situated between the TCO and the mesoporous nanocrystalline TiO2 layer. Besides improving electron extraction, this film could also help to block recombination of electrons transferred to the TCO with oxidized species in the electrolyte, as has been reported in the case of DSSC for compact TiO2 films obtained by other deposition tech-niques [8,9]. The two types of UV-selective sensors were characterized in detail. The current voltage characteristics, spectral response, inten-sity dependence of short circuit current and response times were measured and analyzed in order to evaluate the potential of sealed mesoporous TiO2-based photoelectrochemical cells (PEC) as low cost personal UV-photodetectors.

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This study of photocatalytic oxidation of phenol over titanium dioxide films presents a method for the evaluation of true reaction kinetics. A flat plate reactor was designed for the specific purpose of investigating the influence of various reaction parameters, specifically photocatalytic film thickness, solution flow rate (1–8 l min−1), phenol concentration (20, 40 and 80 ppm), and irradiation intensity (70.6, 57.9, 37.1and 20.4 W m−2), in order to further understand their impact on the reaction kinetics. Special attention was given to the mass transfer phenomena and the influence of film thickness. The kinetics of phenol degradation were investigated with different irradiation levels and initial pollutant concentration. Photocatalytic degradation experiments were performed to evaluate the influence of mass transfer on the reaction and, in addition, the benzoic acid method was applied for the evaluation of mass transfer coefficient. For this study the reactor was modelled as a batch-recycle reactor. A system of equations that accounts for irradiation, mass transfer and reaction rate was developed to describe the photocatalytic process, to fit the experimental data and to obtain kinetic parameters. The rate of phenol photocatalytic oxidation was described by a Langmuir–Hinshelwood type law that included competitive adsorption and degradation of phenol and its by-products. The by-products were modelled through their additive effect on the solution total organic carbon.

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The corset, with its laces and stays, appears to the modern eyes little more than a stylish torture device. However, the corset enjoyed a reputation among the most fashionable women of the nineteenth century. Since small waists were the primary measure of corporeal beauty, corsets were nearly universal among Western women of the middle class upwards. Wearing a corset was also a marker of decency; only lower classes and women of dubious reputation did not wear corsets. From instrument of torture and symbol of submission to its appropriation by women as a marker of sexual liberation, the corset has gone under a sartorial and symbolic transformation remaining the most erotic element of women’s dress. This paper discusses the corset in two Australian films, Picnic at Hanging Rock (Peter Weir, 1974) and Moulin Rouge (Baz Luhrman, 2001), arguing that the corset provides a counterpoint in each film signifying the tension between beauty and respectability, on the one hand, and desire and transgression, on the other. We argue that the corset is the primary prop around which the narrative revolves as well as the key signifying hook for the audience. The fact that erotic motifs are so rare in Australian films makes the centrality of the corset in these films even more powerful as a discursive trope

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Stimulated human whole saliva (WS) was used to study the dynamics of papain hydrolysis at defined pH, ionic strength and temperature with the view of reducing an acquired pellicle. A quartz crystal microbalance with dissipation (QCM-D) was used to monitor the changes in frequency due to enzyme hydrolysis of WS films and the hydrolytic parameters were calculated using an empirical model. The morphological and conformational changes of the salivary films before and after enzymatic hydrolysis were characterized by atomic force microscopy (AFM) imaging and grazing angle infrared spectroscopy (GA-FTIR) spectra, respectively. The characteristics of papain hydrolysis of WS films were pH-, ionic strength- and temperature-dependent. The WS films were partially removed by the action of enzyme, resulting thinner and smoother surfaces. The IR data suggested that hydrolysis-induced deformation did not occur onto the remnants salivary films. The processes of papain hydrolysis of WS films can be controlled by properly regulating pH, ionic strength and temperature.

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Power relations and small and medium-sized enterprise strategies for capturing value in global production networks: visual effects (VFX) service firms in the Hollywood film industry, Regional Studies. This paper provides insights into the way in which non-lead firms manoeuvre in global value chains in the pursuit of a larger share of revenue and how power relations affect these manoeuvres. It examines the nature of value capture and power relations in the global supply of visual effects (VFX) services and the range of strategies VFX firms adopt to capture higher value in the global value chain. The analysis is based on a total of thirty-six interviews with informants in the industry in Australia, the United Kingdom and Canada, and a database of VFX credits for 3323 visual products for 640 VFX firms.

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In 2001 China amended its copyright law in accordance with the requirements of the Agreement on Trade Related Aspects of Intellectual Property (TRIPS). This thesis explores the impact of copyright reform on China’s domestic film and music industries. Through extensive interviews with film and music industry workers – directors, producers, executives, judges, lawyers and musicians – it investigates the role of copyright in film and music’s shift from state driven to commercially focussed. The construction and negotiation of a new ‘copyright culture’ in China is examined through the lens of Yurchak’s (1999) concept of ‘entrepreneurial governmentality.’ Administrative structures put in place prior to China’s economic reform are no longer capable of controlling film and music production and consumption and new approaches to managing it are becoming more important. High levels of unauthorised distribution are forcing these industries to adapt their business models so that they can function in a system with weak copyright protection. Legal, economic and political changes have resulted in the emergence of an ‘entrepreneurial governmentality’ among film and music industry professionals. This commercially focussed group is, in turn, increasing pressure on the state to expand the space in which it can function and support efforts to strengthen the copyright system that allows it to exist. It is suggested that the construction and negotiation of a new ‘copyright culture’ is now taking place. This thesis describes the current situation in the film and music industries. It examines the tension between the theoretical possibilities created by copyright law, and the practical challenges of operating in China. It observes innovative business models being applied by film and music businesses in China. It discusses the impact of traditional attitudes to copying and also examines the role that open licensing models might play in helping limit the negative effects of copyright protection on public access to content and in raising levels of education about copyright among key groups within the community.

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In the decade since the destination branding literature emerged (see for example Pritchard & Morgan 1998, Dosen & Vransevic 1998), only a few books have been published. These are Morgan et al.’s (2002, 2004) edited volumes of international case studies and conceptual papers, and Baker’s (2007) practitioner perspective on branding small cities in the USA. This work by Stephanie Donald and John Gammack is the first research-based text related to destination branding, and is a welcome and timely addition to the field. In the foreword to the first issue of Place Branding and Public Policy, editor Simon Anholt (2004, p. 4) suggested “almost nobody agrees on what, exactly, branding means”, when he described place branding practice as akin to the Wild West. Indeed, this lack of theory was one of the motivators for the authors of this text. Tourism and the Branded City is part of Ashgate’s New Directions in Tourism Analysis series, edited by Dimitri Ioannides. The aim of the series is to address the gap in published theory underpinning the study of tourism, with a particular interest in non-business disciplines such as Sociology, Social Anthropology, Human and Social Geography, and Cultural Studies...

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To evaluate the effect of soft contact lens type on the in vivo tear film surface quality (TFSQ) on daily disposable lenses and to establish whether two recently developed techniques for noninvasive measurement of TFSQ can distinguish between different contact lens types.

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‘Nobody knows anything’, said William Goldman of studio filmmaking. The rule is ever more apt as we survey the radical changes that digital distribution, along with the digitisation of production and exhibition, is wreaking on global film circulation. Digital Disruption: Cinema Moves On-line helps to make sense of what has happened in the short but turbulent history of on-line distribution. It provides a realistic assessment of the genuine and not-so-promising methods that have been tried to address the disruptions that moving from ‘analogue dollars’ to ‘digital cents’ has provoked in the film industry. Paying close attention to how the Majors have dealt with the challenges – often unsuccessfully – it focuses as much attention on innovations and practices outside the mainstream. Throughout, it is alive to, and showcases, important entrepreneurial innovations such as Mubi, Jaman, Withoutabox and IMDb. Written by leading academic commentators that have followed the fortunes of world cinema closely and passionately, as well as experienced hands close to the fluctuating fortunes of the industry, Digital Disruption: Cinema Moves On-line is an indispensable guide to great changes in film and its audiences.