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Die vorliegende Magisterarbeit beschäftigt sich mit der Rezipientenforschung, genauer gesagt mit der Motivforschung. Dies ist ein Teilgebiet der Publizistik- und Kommunikationswissenschaft. Als Untersuchungsgegenstand wird das Format „Big Brother“, Staffel 10 herangezogen. Es wird der Frage nachgegangen, aus welchen Gründen sich die Rezipienten diesem Format zuwenden. Hier ist wichtig zu erwähnen, dass innerhalb der Arbeit Vergleiche mit den bisher vorhandenen Studienergebnissen auf diesem Gebiet angestrebt werden. Es soll geklärt werden, ob eine Verschiebung der Rezeptionsmotive im Laufe der Jahre und in Anbetracht der ausgestrahlten Staffeln stattgefunden hat. Die Arbeit nähert sich dem Thema „Reality TV“ und gibt Hinweise über Definition und Weiterentwicklungen. Das Genre der „Real Life Soap“ wird im Zuge dieser Arbeit ebenfalls genauer beleuchtet. Anschließend folgt die Einführung in die Thematik rund um „Big Brother“. Die wichtigsten Highlights der bereits gezeigten Staffeln werden dargestellt und die Rahmenbedingungen der zehnten Staffel werden erklärt. Durch eine quantitative Befragung mittels Online-Fragebogen sollen die Motive und Zuwendungsgründe ermittelt werden

Domain walls of ferroelectric BaTiO3 within the Ginzburg-Landau-Devonshire phenomenological model

Mechanically compatible and electrically neutral domain walls in tetragonal, orthorhombic and rhombohedral ferroelectric phases of BaTiO3 are systematically investigated in the framework of the phenomenological Ginzburg-Landau-Devonshire (GLD) model with parameters of Ref. [Hlinka and Marton, Phys. Rev. 74, 104104 (2006)]. Polarization and strain profiles within domain walls are calculated numerically and within an approximation leading to the quasi-one-dimensional analytic solutions applied previously to the ferroelectric walls of the tetragonal phase [W. Cao and L.E. Cross, Phys. Rev. 44, 5 (1991)]. Domain wall thicknesses and energy densities are estimated for all mechanically compatible and electrically neutral domain wall species in the entire temperature range of ferroelectric phases. The model suggests that the lowest energy walls in the orthorhombic phase of BaTiO3 are the 90-degree and 60-degree walls. In the rhombohedral phase, the lowest energy walls are the 71-degree and 109-degree walls. All these ferroelastic walls have thickness below 1 nm except for the 90-degree wall in the tetragonal phase and the 60-degree S-wall in the orthorhombic phase, for which the larger thickness of the order of 5 nm was found. The antiparallel walls of the rhombohedral phase have largest energy and thus they are unlikely to occur. The calculation indicates that the lowest energy structure of the 109-degree wall and few other domain walls in the orthorhombic and rhombohedral phases resemble Bloch-like walls known from magnetism.Comment: 12 pages, 9 figure

Effect of surface tension and depolarization field on ferroelectric nanomaterials properties

The theory of size effects of the properties of nanocrystalline ferroelectric ceramic or nanoparticle powder allowing for surface tension and depolarization field is proposed. Surface tension was included into free energy functional and surface energy was expressed via surface tension coefficient. The latter was shown to be dependent on temperature due to its relation to dielectric permittivity of the nanoparticles. The depolarization field effect was calculated in the model taking into account the space charge layer on the surface, this space-charge being able to compensate depolarization field in the bulk material. Euler-Lagrange Equation for inhomogeneous polarization of nanomaterial with boundary condition where extrapolation length was shown to be temperature dependent quantity was solved analytically both in paraelectric and ferroelectric phase of size driven phase transition. This phase transition critical temperature dependence on the particle size was calculated. Temperature and size dependence of nanomaterials polarization and dielectric susceptibility was obtained. The possibility to calculate these and other properties by minimization of conventional free energy in the form of different power polarization series, but with the coefficients which depend on particles size, temperature, contribution of depolarization field and surface tension coefficient was demonstrated. These latter effects were shown to influence essentially the nanomaterial properties. The comparison with available experimental data is performed.Comment: 30 pages, 11 figure

Size effects and depolarization field influence on the phase diagrams of cylindrical ferroelectric nanoparticles

Ferroelectric nanoparticles of different shape and their nanocomposites are actively studied in modern physics. Because of their applications in many fields of nanotechnology, the size effects and the possible disappearance of ferroelectricity at a critical particle volume attract a growing scientific interest. In this paper we study the size effects of the cylindrical nanoparticle phase diagrams allowing for effective surface tension and depolarization field influence. The Euler-Lagrange equations were solved by direct variational method. The approximate analytical expression for the paraelectric-ferroelectric transition temperature dependence on nanoparticle sizes, polarization gradient coefficient, extrapolation length, effective surface tension and electrostriction coefficient was derived. It was shown that the transition temperature could be higher than the one of the bulk material for nanorods and nanowires in contrast to nanodisks, where the decrease takes place. The critical sizes and volume of ferroelectric-paraelectric phase transition are calculated. We proved that among all cylindrical shapes a nanobar reveals the minimal critical volume. We predicted the enhancement of ferroelectric properties in nanorods and nanowires. Obtained results explain the observed ferroelectricity enhancement in nanorods and could be very useful for elaboration of modern nanocomposites with perfect polar properties.Comment: 22 pages, 7 figures, 1 tabl

Precise determination of polarization fields in c-plane GaN/Al x Ga1-x N/GaN heterostructures with capacitance--voltage-measurements

Due to changes in the spontaneous and piezoelectric polarization, AlGaN/GaN heterostructures exhibit strong polarization fields at heterointerfaces. For quantum wells, the polarization fields lead to a strong band bending and a redshift of the emission wavelength, known as quantum-confined Stark effect. In this paper the polarization fields of thin AlGaN layers in a GaN matrix were determined by evaluating the changes in the depletion region width in comparison to a reference sample without heterostructure using capacitance-voltage-measurements. The polarization fields for Al0.09Ga0.91N (0.6 +/- 0.7 MV cm(-1)), Al0.26Ga0.74N (2.3 +/- 0.6 MV cm(-1)), Al0.34Ga0.66N (3.1 +/- 0.6 MV cm(-1)), Al0.41Ga0.59N (4.0 +/- 0.7 MV cm(-1)) and Al0.47Ga0.53N (5.0 +/- 0.8 MV cm(-1)) heterostructures were determined. The results of the field strength and field direction of all samples are in excellent agreement with values predicted by theory and a capacitance-voltage based Poisson-carrier transport simulation approach giving experimental evidence for a nonlinear increasing polarization field with Al-concentration. (C) 2019 The Japan Society of Applied Physic

Role of substrate quality on the performance of semipolar (11 2 - 2) InGaN light-emitting diodes

We compare the optical properties and device performance of unpackaged InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) emitting at ∼430 nm grown simultaneously on a high-cost small-size bulk semipolar (11 2 - 2) GaN substrate (Bulk-GaN) and a low-cost large-size (11 2 - 2) GaN template created on patterned (10 1 - 2) r-plane sapphire substrate (PSS-GaN). The Bulk-GaN substrate has the threading dislocation density (TDD) of ∼ and basal-plane stacking fault (BSF) density of 0 cm-1, while the PSS-GaN substrate has the TDD of ∼2 × 108cm-2 and BSF density of ∼1 × 103cm-1. Despite an enhanced light extraction efficiency, the LED grown on PSS-GaN has two-times lower internal quantum efficiency than the LED grown on Bulk-GaN as determined by photoluminescence measurements. The LED grown on PSS-GaN substrate also has about two-times lower output power compared to the LED grown on Bulk-GaN substrate. This lower output power was attributed to the higher TDD and BSF density

Boxnep - модульный подводный робот перспективных технологий

The article discusses the relevance of the underwater vehicles are able to solve a wide range of problems. The decision puts in a basis of the research is designing a modular underwater robot. It allows to make a mounting of various equipment and testing it in the water medium. The paper deals with the concept of the robot and its characteristics