Electron-Doping Mottronics in Strongly Correlated Perovskite

The discovery of hydrogen-induced electron localization and highly insulating states in d-band electron correlated perovskites has opened a new paradigm for exploring novel electronic phases of condensed matters and applications in emerging field-controlled electronic devices (e.g., Mottronics). Although a significant understanding of doping-tuned transport properties of single crystalline correlated materials exists, it has remained unclear how doping-controlled transport properties behave in the presence of planar defects. The discovery of an unexpected high-concentration doping effect in defective regions is reported for correlated nickelates. It enables electronic conductance by tuning the Fermi-level in Mott–Hubbard band and shaping the lower Hubbard band state into a partially filled configuration. Interface engineering and grain boundary designs are performed for H_xSmNiO₃/SrRuO₃ heterostructures, and a Mottronic device is achieved. The interfacial aggregation of hydrogen is controlled and quantified to establish its correlation with the electrical transport properties. The chemical bonding between the incorporated hydrogen with defective SmNiO₃ is further analyzed by the positron annihilation spectroscopy. The present work unveils new materials physics in correlated materials and suggests novel doping strategies for developing Mottronic and iontronic devices via hydrogen-doping-controlled orbital occupancy in perovskite heterostructures.     

Innovative polyelectrolytes/poly(ionic liquid)s for energy and the environment

This paper presents the work carried out within the European project RENAISSANCE‐ITN, which was dedicated to the development of innovative polyelectrolytes for energy and environmental applications. Within the project different types of innovative polyelectrolytes were synthesized such as poly(ionic liquid)s coming from renewable or natural ions, thiazolium cations, catechol functionalities or from a new generation of cheap deep eutectic monomers. Further, macromolecular architectures such as new poly(ionic liquid) block copolymers and new (semi)conducting polymer/polyelectrolyte complexes were also developed. As the final goal, the application of these innovative polymers in energy and the environment was investigated. Important advances in energy storage technologies included the development of new carbonaceous materials, new lignin/conducting polymer biopolymer electrodes, new iongels and single‐ion conducting polymer electrolytes for supercapacitors and batteries and new poly(ionic liquid) binders for batteries. On the other hand, the use of innovative polyelectrolytes in sustainable environmental technologies led to the development of new liquid and dry water, new materials for water cleaning technologies such as flocculants, oil absorbers, new recyclable organocatalyst platforms and new multifunctional polymer coatings with antifouling and antimicrobial properties. All in all this paper demonstrates the potential of poly(ionic liquid)s for high‐value applications in energy and enviromental areas. © 2017 Society of Chemical Industry     

Development of morphological properties of road surfacing aggregates during the polishing process

This study investigated the morphological properties of different road surfacing aggregates. Eleven types of aggregates with great variances in their mineralogical properties were chosen for the study. For each type, 500-gram test samples were prepared and subjected to polishing using the Micro-Deval (MD) apparatus. Before and after polishing, 48 particles from each type of aggregate were selected and run through the aggregate imaging system and X-ray computed tomography equipment to capture the change of morphological characteristics, including sphericity, angularity and texture. The results showed that log-normal functions are ideally suited to describe distributions of the analysed morphological characteristics before and after MD. The mass loss of each aggregate can be well described with a function using the expected value of morphological parameters with the aid of a multiple regression analysis. The change of angularity is the main cause for the mass loss whilst the changes of both the sphericity and texture only have an ancillary influence.     

The formation of virtual organizations by means of electronic institutions in a 3D e-Tourism environment

In this article we showcase an agent-mediated B2C and B2B e-Marketplace. This e-Marketplace is part of the social and immersive 3D e-Tourism environment “Itchy Feet”. We give an overview of the framework that forms the basis of the e-Marketplace and show how it is used to create B2C-, B2B- and Virtual Organizations that are visualized in a 3D Virtual World. This interface provides users with an intuitive and easy way to interact with humans and software agents by means of a 3D Virtual World. The business logic is realized by autonomous software agents offering services to customers. The e-Marketplace is regulated by Electronic Institutions to ensure that all participants adhere to the rules of the market. The article is concluded with a detailed discussion on bridging the gaps between Multi-Agent Systems and 3D Virtual Worlds and the preliminary results of a conducted usability study of “Itchy Feet”.     

Avoiding crack nucleation and propagation during upset bulging of tubes

As an alternative to joining by fusion welding, joining by upset bulging (JUB) can be applied in cases where tubes are joined to plates, sheet metal, or other tubes and profiles. If a tube is joined to a pierced flat plate, joining is accomplished by creating bulges in the tube by axial compression, which enclose and securely lock the plate. The JUB process has a large potential for reducing cycle times, realizing joints between different materials and for increasing the dimensional accuracy of the joints compared to fusion welding. The joints produced by this forming technique are free from the negative impact of heat affected zones on the material properties. However, the material undergoes large plastic deformation during the JUB process. When the bulges are fully compressed, local damage and failure can be observed which reduce the service life properties of the joints. This paper presents an experimental and numerical study of the damage evolution and crack initiation in mechanical joining by upset bulging. Experiments were carried out to analyse the occurrence of failure. The results are supported by FE analyses. Nucleation of cracks strongly depends on the final bulge height and consequently on the degree of deformation on the inner side of bulges. Tensile tests show that cracks in the bulge reduce the strength of the joint to half of the undamaged material. A new bulge design with a modified shape is presented, which reduces the damaging effect of the upset bulging process and thus improves the strength of the joints.     

The rate of growth in scientific publication and the decline in coverage provided by Science Citation Index

The growth rate of scientific publication has been studied from 1907 to 2007 using available data from a number of literature databases, including Science Citation Index (SCI) and Social Sciences Citation Index (SSCI). Traditional scientific publishing, that is publication in peer-reviewed journals, is still increasing although there are big differences between fields. There are no indications that the growth rate has decreased in the last 50 years. At the same time publication using new channels, for example conference proceedings, open archives and home pages, is growing fast. The growth rate for SCI up to 2007 is smaller than for comparable databases. This means that SCI was covering a decreasing part of the traditional scientific literature. There are also clear indications that the coverage by SCI is especially low in some of the scientific areas with the highest growth rate, including computer science and engineering sciences. The role of conference proceedings, open access archives and publications published on the net is increasing, especially in scientific fields with high growth rates, but this has only partially been reflected in the databases. The new publication channels challenge the use of the big databases in measurements of scientific productivity or output and of the growth rate of science. Because of the declining coverage and this challenge it is problematic that SCI has been used and is used as the dominant source for science indicators based on publication and citation numbers. The limited data available for social sciences show that the growth rate in SSCI was remarkably low and indicate that the coverage by SSCI was declining over time. National Science Indicators from Thomson Reuters is based solely on SCI, SSCI and Arts and Humanities Citation Index (AHCI). Therefore the declining coverage of the citation databases problematizes the use of this source.     

Influence of lighting conditions on the appearance of typical interior materials

Two studies investigated how lighting influences perception of various materials. Experiment 1 focused on preferences of cold or warm light. Participants' task was to indicate preference for either coolish or warmish light for 20 different materials. The selection included materials typically used for wall or floor of interior spaces. Different hues and surface characteristics were present. Specifically two materials of blue color (cold hue) were preferred in a cold light while red carpet (warm hue) and synthetic turf materials were preferred in warm light. This latter choice was explained by automatic reference of synthetic turf to the appearance of natural grass. There were no clear light source preferences for other materials. Experiment 2 explored how the same 20 materials are evaluated under LED lighting in comparison to three other lighting situations (halogen lamp, high‐intensity discharge lamp, and compact fluorescent lamp). The results of this explorative study were not conclusive. The materials chosen for this experiment differed greatly in their structure and optical properties. In conclusion, light influence on the evaluation of materials needs systematic investigation in future research. © 2013 Wiley Periodicals, Inc. Col Res Appl, 40, 50–61, 2015     

An end-to-end tool chain for Sensory Experience based on MPEG-V

This paper provides an overview of our research conducted in the area of Sensory Experience including our implementations using MPEG-V Part 3 entitled “Sensory Information”. MPEG-V Part 3 introduces Sensory Experience as a tool to increase the Quality of Experience by annotating traditional multimedia data with sensory effects. These sensory effects are rendered on special devices like fans, vibration chairs, ambient lights, scent disposers, water sprayers, or heating/cooling devices stimulating senses beyond the traditional ones. The paper's main focus is on the end-to-end aspects including the generation, transmission, and synchronized rendering of sensory effects with the traditional multimedia data taking movie clips as an example. Therefore, we present in this paper an open source tool chain that provides a complete end-to-end sensory effect generation and consumption framework. Furthermore, we summarize results from various subjective quality assessments conducted in this area. Finally, we point out research challenges that may encourage further research within this emerging domain.     

Front dynamics in catalytic surface reactions

A variety of pattern formation phenomena in catalytic surface reactions can be attributed to the dynamics of interfaces, or fronts, separating distinct uniform states. The states may represent surface coverages by different adsorbates or in the case of forced oscillations, different phases of oscillation. The dynamics of fronts are strongly affected by front instabilities and by diffusion anisotropy. We identify two new pattern formation mechanisms associated with different front behaviors in orthogonal directions: an ordering process by which stationary labyrinths in an isotropic system evolve into ordered stationary stripes, and confinement of isotropic spatiotemporal chaos to one space dimension, a state we term stratified chaos.