26 research outputs found
Design of a product using polymer light-emitting diodes
No full textSince the discovery of intrinsically conducting polymers in 1977 and the development of light-emitting polymers since 1990, a great amount of scientific research has been devoted to these fields. As a result, improvements have been made in material properties, which pushes the technology further towards the market. These materials are widely predicted to have a bright future with great commercial potential. This certainly is true for polymer Light-Emitting Diodes (LEDs). No systematic assessment of their market potential can be found in the literature, however. Nor does anyone seem to have taken a realistic look into the future in order to predict trends and the implications they will have for polymer LED devices and applications. Because research in this area is currently moving past the initial phase and towards processing and application, an impression of future applications is needed in order to guide research efforts in commercially attractive directions. In this thesis a systematic and realistic look will be taken into the future of polymer LEDs. The characteristic properties of polymer LEDs will be described alongside the properties of relevant, competing technologies; comparison will reveal the relative strengths and weaknesses of each. PolyLEDs’ strengths and weaknesses will then form the basis of attempts to generate ideas for promising applications. Three criteria will be used to measure an application’s promise: feasibility, uniqueness, and commercial attractiveness. The promising applications that are thus found will then be placed in time. This will be done by making predictions of the developments that can realistically be expected to take place regarding the critical properties -- lifetime, light output and device area -- and then assessing against these predictions the promising applications’ requirements in terms of these properties. The result of this process will be to roughly sketch a path for the commercialization of polyLEDs. The commercial obstacles that exist on this path will also be discussed…Applied SciencesIndustrial Design Engineerin
High-pressure 155Gd Mössbauer experiments on Gd intermetallic compounds compared with first-principles band-structure calculations
No full textEnhanced magnetocaloric effects and tunable thermal hysteresis in transition metal pnictides
No full textThe effect of Co and Ni substitutions for Fe on the magnetocaloric properties of MnFe(P,Ge) compounds crystallizing in the hexagonal Fe2P type of structure was studied. It was found that, by changing composition, a small thermal hysteresis and a giant magnetocaloric effect can be obtained simultaneously in MnFe(P,Ge) compounds when the magnetic transition is controlled to be close to the border separating the first- and second-order transition regimes.Fundamental Aspects of Materials and Energy (FAME)Applied Science
Two types of magnetism in the magnetic superconductor TmNi2B2C related to the degree of carbon-site occupancy
No full textRealization of aligned three-dimensional single-crystal chromium nanostructures by thermal evaporation
Get PDFAligned three-dimensional single-crystal chromium nanostructures are fabricated onto a silicon substrate by thermal evaporation in a conventional thermal evaporator, where the incident angle of Cr vapor flux with respect to the substrate surface normal is fixed at 88°. The effects of the deposition time and incident angle on the morphology of the resulting nanostructures are investigated. The achieved Cr nanostructures are characterized by scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and surface area measurement. This study provides a convenient way to fabricate three-dimensional single-crystal Cr nanostructures, which is suitable for batch fabrication and mass production. Finally, the same technique is employed to fabricate the nanostructures of other metals such as Ag, Au, Pd, and Ni
Factors influencing consumer acceptance of vehicle-to-grid by electric vehicle drivers in the Netherlands
No full textThe objective of this study is to identify factors that influence actual electric vehicle (EV) drivers’ acceptance of Vehicle-to-Grid (V2G) charging. The study takes a qualitative approach in order to provide insight into actual EV users’ perceptions of V2G technology and their underlying motivation to accept or not accept V2G. The Theory of Planned Behaviour is adopted to create a basic conceptual model of the potential factors influencing users’ acceptance of V2G. Twenty semi-structured interviews are conducted among Dutch EV drivers, including both regular EV drivers, as well as participants who had previously taken part in V2G projects. The factors that are found to be most important for fostering acceptance are financial compensation, transparent communication and reliable control of the system by the user. On the other hand, the factors that are found to have a negative effect on acceptance are range anxiety, discomfort experienced while participating and battery degradation. Our study shows that the majority of our interview participants accept V2G albeit with some reservations and caution. As EVs and V2G are new technologies, our sample of twenty actual EV users consists of early adopters. As such, their attitudes may not reflect those of the majority of future users. However, our study suggests that there are EV users who are willing to use V2G charge points and will continue to do so. The reasons behind such user acceptance are further described in the study together with additional insights and ideas for future research
