13 results on '"Hübner, R."'
Search Results
2. The effect of expertise on the creation and evaluation of visual compositions in terms of creativity and beauty.
- Author
-
Mutter Y and Hübner R
- Subjects
- Humans, Female, Male, Adult, Art, Young Adult, Creativity, Beauty
- Abstract
The identification of artistically creative individuals is an important matter in the fields of art, design, and psychology. One promising approach involves assessing a person's products rather than his or her personality or cognitive processes. However, the necessity of expert involvement in such evaluations is still debated. To investigate this issue, two experiments were conducted, each consisting of a production phase and an evaluation phase. In Experiment 1, participants were asked to compose a most beautiful picture, which was subsequently assessed in terms of beauty. Experiment 2 was analogous, but participants were asked to compose a most creative picture, which was then assessed in terms of creativity and beauty. The results revealed that expertise did not play a crucial role in the creation or evaluation of beauty. Both experts and non-experts largely agreed on what constitutes beauty. However, when it came to the production and assessment of creative pictures, experts had an advantage. They were the only group that was able to predict a person's creativity based on the evaluation of his or her product., (© 2024. The Author(s).)
- Published
- 2024
- Full Text
- View/download PDF
3. Investigations towards incorporation of Eu 3+ and Cm 3+ during ZrO 2 crystallization in aqueous solution.
- Author
-
Opitz L, Hübner R, Shams Aldin Azzam S, Gilson SE, Finkeldei SC, and Huittinen N
- Abstract
Nuclear energy provides a widely applied carbon-reduced energy source. Following operation, the spent nuclear fuel (SNF), containing a mixture of radiotoxic elements such as transuranics, needs to be safely disposed of. Safe storage of SNF in a deep geological repository (DGR) relies on multiple engineered and natural retention barriers to prevent environmental contamination. In this context, zirconia (ZrO
2 ) formed on the SNF rod cladding, could be employed as an engineered barrier for immobilization of radionuclides via structural incorporation. This study investigates the incorporation of Eu3+ and Cm3+ , representatives for trivalent transuranics, into zirconia by co-precipitation and crystallization in aqueous solution at 80 °C. Complementary structural and microstructural characterization has been carried out by powder X-ray diffraction (PXRD), spectrum imaging analysis based on energy-dispersive X-ray spectroscopy in scanning transmission electron microscopy mode (STEM-EDXS), and luminescence spectroscopy. The results reveal the association of the dopants with the zirconia particles and elucidate the presence of distinct bulk and superficially incorporated species. Hydrothermal aging for up to 460 days in alkaline media points to great stability of these incorporated species after initial crystallization, with no indication of phase segregation or release of Eu3+ and Cm3+ over time. These results suggest that zirconia would be a suitable technical retention barrier for mobilized trivalent actinides in a DGR., (© 2023. The Author(s).)- Published
- 2023
- Full Text
- View/download PDF
4. Evidence that the aesthetic preference for Hogarth's Line of Beauty is an evolutionary by-product.
- Author
-
Hübner R, Lewis DMG, Al-Shawaf L, Semchenko AY, and Flores J
- Subjects
- Pregnancy, Humans, Female, Esthetics, Biological Evolution, Exercise, Beauty, Art
- Abstract
In 1753, artist William Hogarth declared a specific S-shaped line to be the 'Line of Beauty' (LoB). Hogarth's assertion has had a profound impact on diverse fields over the past two and a half centuries. However, only one recent (2022) study has investigated whether Hogarth's assertion accurately captures humans' actual aesthetic preferences, and no research has explored why people find the LoB beautiful. We conducted two studies testing the hypothesis that the LoB's perceived beauty is an incidental by-product of cognitive systems that evolved to attend to fitness-relevant morphological features in people. In Study 1, we replicated the finding that female bodies whose lumbar curvature approximates the biomechanical optimum for dealing with the exigencies of pregnancy are rated as more attractive. In Study 2, we found that abstract lines extracted from these bodies were perceived as more beautiful than other lines. These results suggest that the preference for Hogarth's LoB is an incidental by-product of psychological mechanisms that evolved for other purposes. More broadly, these findings suggest that an evolutionary psychological approach - in particular the concept of evolutionary by-product - may be useful for understanding, explaining, and predicting people's aesthetic preferences for certain abstract symbols, which otherwise might seem arbitrary and inexplicable., (© 2023. The Author(s).)
- Published
- 2023
- Full Text
- View/download PDF
5. Dependence of the damage in optical metal/dielectric coatings on the energy of ions in irradiation experiments for space qualification.
- Author
-
Pelizzo MG, Corso AJ, Santi G, Hübner R, Garoli D, Doyle D, Lubin P, Cohen AN, Erlikhman J, Favaro G, Bazzan M, Drobny J, Curreli D, and Umansky M
- Abstract
Terrestrial accelerator facilities can generate ion beams which enable the testing of the resistance of materials and thin film coatings to be used in the space environment. In this work, a [Formula: see text]/Al bi-layer coating has been irradiated with a [Formula: see text] beam at three different energies. The same flux and dose have been used in order to investigate the damage dependence on the energy. The energies were selected to be in the range 4-100 keV, in order to consider those associated to the quiet solar wind and to the particles present in the near-Earth space environment. The optical, morphological and structural modifications have been investigated by using various techniques. Surprisingly, the most damaged sample is the one irradiated at the intermediate energy, which, on the other hand, corresponds to the case in which the interface between the two layers is more stressed. Results demonstrate that ion energies for irradiation tests must be carefully selected to properly qualify space components.
- Published
- 2021
- Full Text
- View/download PDF
6. Effect of insertion layer on electrode properties in magnetic tunnel junctions with a zero-moment half-metal.
- Author
-
Titova A, Fowley C, Clifford E, Lau YC, Borisov K, Betto D, Atcheson G, Hübner R, Xu C, Stamenov P, Coey M, Rode K, Lindner J, Fassbender J, and Deac AM
- Abstract
Due to its negligible spontaneous magnetization, high spin polarization and giant perpendicular magnetic anisotropy, Mn
2 Rux Ga (MRG) is an ideal candidate as an oscillating layer in THz spin-transfer-torque nano-oscillators. Here, the effect of ultrathin Al and Ta diffusion barriers between MRG and MgO in perpendicular magnetic tunnel junctions is investigated and compared to devices with a bare MRG/MgO interface. Both the compensation temperature, Tcomp , of the electrode and the tunneling magnetoresistance (TMR) of the device are highly sensitive to the choice and thickness of the insertion layer used. High-resolution transmission electron microscopy, as well as analysis of the TMR, its bias dependence, and the resistance-area product allow us to compare the devices from a structural and electrical point of view. Al insertion leads to the formation of thicker effective barriers and gives the highest TMR, at the cost of a reduced Tcomp . Ta is the superior diffusion barrier which retains Tcomp , however, it also leads to a much lower TMR on account of the short spin diffusion length which reduces the tunneling spin polarization. The study shows that fine engineering of the Mn2 Rux Ga/barrier interface to improve the TMR amplitude is feasible.- Published
- 2019
- Full Text
- View/download PDF
7. Structure-property relationship of Co 2 MnSi thin films in response to He + -irradiation.
- Author
-
Hammerath F, Bali R, Hübner R, Brandt MRD, Rodan S, Potzger K, Böttger R, Sakuraba Y, and Wurmehl S
- Abstract
We investigated the structure-property relationship of Co
2 MnSi Heusler thin films upon the irradiation with He+ ions. The variation of the crystal structure with increasing ion fluence has been probed using nuclear magnetic resonance (NMR) and transmission electron microscopy (TEM), and associated with the corresponding changes of the magnetic behavior. A decrease of both the structural order and the moment in saturation is observed. Specifically, we detect a direct transition from a highly L21 -ordered to a fully A2-disordered structure type and quantify the evolution of the A2 structural contribution as a function of ion fluence. Complementary TEM analysis reveals a spatially-resolved distribution of the L21 and A2 phases showing that the A2 disorder starts at the upper part of the films. The structural degradation in turn leads to a decreasing magnetic moment in saturation in response to the increasing fluence.- Published
- 2019
- Full Text
- View/download PDF
8. On the insulator-to-metal transition in titanium-implanted silicon.
- Author
-
Liu F, Wang M, Berencén Y, Prucnal S, Engler M, Hübner R, Yuan Y, Heller R, Böttger R, Rebohle L, Skorupa W, Helm M, and Zhou S
- Abstract
Hyperdoped silicon with deep level impurities has attracted much research interest due to its promising optical and electrical properties. In this work, single crystalline silicon supersaturated with titanium is fabricated by ion implantation followed by both pulsed laser melting and flash lamp annealing. The decrease of sheet resistance with increasing Ti concentration is attributed to a surface morphology effect due to the formation of cellular breakdown at the surface and the percolation conduction at high Ti concentration is responsible for the metallic-like conductivity. The insulator-to-metal transition does not happen. However, the doping effect of Ti incorporation at low concentration is not excluded, which might be responsible for the sub-bandgap optical absorption reported in literature.
- Published
- 2018
- Full Text
- View/download PDF
9. Room-temperature short-wavelength infrared Si photodetector.
- Author
-
Berencén Y, Prucnal S, Liu F, Skorupa I, Hübner R, Rebohle L, Zhou S, Schneider H, Helm M, and Skorupa W
- Abstract
The optoelectronic applications of Si are restricted to the visible and near-infrared spectral range due to its 1.12 eV-indirect band gap. Sub-band gap light detection in Si, for instance, has been a long-standing scientific challenge for many decades since most photons with sub-band gap energies pass through Si unabsorbed. This fundamental shortcoming, however, can be overcome by introducing non-equilibrium deep-level dopant concentrations into Si, which results in the formation of an impurity band allowing for strong sub-band gap absorption. Here, we present steady-state room-temperature short-wavelength infrared p-n photodiodes from single-crystalline Si hyperdoped with Se concentrations as high as 9 × 10
20 cm-3 , which are introduced by a robust and reliable non-equilibrium processing consisting of ion implantation followed by millisecond-range flash lamp annealing. We provide a detailed description of the material properties, working principle and performance of the photodiodes as well as the main features in the studied wavelength region. This work fundamentally contributes to establish the short-wavelength infrared detection by hyperdoped Si in the forefront of the state-of-the-art of short-IR Si photonics.- Published
- 2017
- Full Text
- View/download PDF
10. Controllable growth of vertically aligned graphene on C-face SiC.
- Author
-
Liu Y, Chen L, Hilliard D, Huang QS, Liu F, Wang M, Böttger R, Hübner R, N'Diaye AT, Arenholz E, Heera V, Skorupa W, and Zhou S
- Abstract
We investigated how to control the growth of vertically aligned graphene on C-face SiC by varying the processing conditions. It is found that, the growth rate scales with the annealing temperature and the graphene height is proportional to the annealing time. Temperature gradient and crystalline quality of the SiC substrates influence their vaporization. The partial vapor pressure is crucial as it can interfere with further vaporization. A growth mechanism is proposed in terms of physical vapor transport. The monolayer character of vertically aligned graphene is verified by Raman and X-ray absorption spectroscopy. With the processed samples, d
0 magnetism is realized and negative magnetoresistance is observed after Cu implantation. We also prove that multiple carriers exist in vertically aligned graphene.- Published
- 2016
- Full Text
- View/download PDF
11. Projected loss of soil organic carbon in temperate agricultural soils in the 21(st) century: effects of climate change and carbon input trends.
- Author
-
Wiesmeier M, Poeplau C, Sierra CA, Maier H, Frühauf C, Hübner R, Kühnel A, Spörlein P, Geuß U, Hangen E, Schilling B, von Lützow M, and Kögel-Knabner I
- Abstract
Climate change and stagnating crop yields may cause a decline of SOC stocks in agricultural soils leading to considerable CO2 emissions and reduced agricultural productivity. Regional model-based SOC projections are needed to evaluate these potential risks. In this study, we simulated the future SOC development in cropland and grassland soils of Bavaria in the 21(st) century. Soils from 51 study sites representing the most important soil classes of Central Europe were fractionated and derived SOC pools were used to initialize the RothC soil carbon model. For each site, long-term C inputs were determined using the C allocation method. Model runs were performed for three different C input scenarios as a realistic range of projected yield development. Our modelling approach revealed substantial SOC decreases of 11-16% under an expected mean temperature increase of 3.3 °C assuming unchanged C inputs. For the scenario of 20% reduced C inputs, agricultural SOC stocks are projected to decline by 19-24%. Remarkably, even the optimistic scenario of 20% increased C inputs led to SOC decreases of 3-8%. Projected SOC changes largely differed among investigated soil classes. Our results indicated that C inputs have to increase by 29% to maintain present SOC stocks in agricultural soils.
- Published
- 2016
- Full Text
- View/download PDF
12. Anisotropic metal growth on phospholipid nanodiscs via lipid bilayer expansion.
- Author
-
Oertel J, Keller A, Prinz J, Schreiber B, Hübner R, Kerbusch J, Bald I, and Fahmy K
- Subjects
- Anisotropy, Gold chemistry, Lipid Bilayers chemistry, Nanoparticles chemistry, Phospholipids chemistry
- Abstract
Self-assembling biomolecules provide attractive templates for the preparation of metallic nanostructures. However, the intuitive transfer of the "outer shape" of the assembled macromolecules to the final metallic particle depends on the intermolecular forces among the biomolecules which compete with interactions between template molecules and the metal during metallization. The shape of the bio-template may thus be more dynamic than generally assumed. Here, we have studied the metallization of phospholipid nanodiscs which are discoidal particles of ~10 nm diameter containing a lipid bilayer ~5 nm thick. Using negatively charged lipids, electrostatic adsorption of amine-coated Au nanoparticles was achieved and followed by electroless gold deposition. Whereas Au nanoparticle adsorption preserves the shape of the bio-template, metallization proceeds via invasion of Au into the hydrophobic core of the nanodisc. Thereby, the lipidic phase induces a lateral growth that increases the diameter but not the original thickness of the template. Infrared spectroscopy reveals lipid expansion and suggests the existence of internal gaps in the metallized nanodiscs, which is confirmed by surface-enhanced Raman scattering from the encapsulated lipids. Interference of metallic growth with non-covalent interactions can thus become itself a shape-determining factor in the metallization of particularly soft and structurally anisotropic biomaterials.
- Published
- 2016
- Full Text
- View/download PDF
13. Direct Depth- and Lateral- Imaging of Nanoscale Magnets Generated by Ion Impact.
- Author
-
Röder F, Hlawacek G, Wintz S, Hübner R, Bischoff L, Lichte H, Potzger K, Lindner J, Fassbender J, and Bali R
- Abstract
Nanomagnets form the building blocks for a variety of spin-transport, spin-wave and data storage devices. In this work we generated nanoscale magnets by exploiting the phenomenon of disorder-induced ferromagnetism; disorder was induced locally on a chemically ordered, initially non-ferromagnetic, Fe60Al40 precursor film using nm diameter beam of Ne(+) ions at 25 keV energy. The beam of energetic ions randomized the atomic arrangement locally, leading to the formation of ferromagnetism in the ion-affected regime. The interaction of a penetrating ion with host atoms is known to be spatially inhomogeneous, raising questions on the magnetic homogeneity of nanostructures caused by ion-induced collision cascades. Direct holographic observations of the flux-lines emergent from the disorder-induced magnetic nanostructures were made in order to measure the depth- and lateral- magnetization variation at ferromagnetic/non-ferromagnetic interfaces. Our results suggest that high-resolution nanomagnets of practically any desired 2-dimensional geometry can be directly written onto selected alloy thin films using a nano-focussed ion-beam stylus, thus enabling the rapid prototyping and testing of novel magnetization configurations for their magneto-coupling and spin-wave properties.
- Published
- 2015
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.