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Janus particles, named after the two faced Roman god Janus, possess unique asymmetry and combine two distinct functions at their opposite sides, allowing them to target complex self-assembled architectures and materials inaccessible for homogeneous building blocks. In this study, three areas regarding the topic of Janus particles were explored: the synthesis of Janus particles, their (self-) assembly, and applications. In the first part of the work, we have drawn our attention to the optimization of the synthetic procedures concerning the preparation of Janus particles and to the extending of the current Janus particle library by adding new geometries to the list. In the case of spherical Janus particles, we have developed an easy approach to tailor the Janus ratio of the resulting particles, thus, extending the possibilities of the Pickering emulsion approach for the creation of a variety of Janus particle architectures. Additionally, a new methodology was employed to measure directly and in situ the position/contact angle of the prepared Janus particles with different Janus ratios at a water-oil interface. It was further concluded that having simply two different functionalities on a particle surface does not necessarily imply amphiphilic behavior: only in the case of large wettability contrasts our particles were in a true Janus regime. In the case of platelet-like Janus particles, we have developed a completely new approach for their large-scale synthesis, which involved a reduced number of steps compared to the spherical Janus particles. In the second part of the work, the assembly behavior of various kinds of functional spherical Janus particles was investigated depending on the nature of the Janus particles and the surrounding media conditions. Oppositely charged, uncharged amphiphilic, and charged amphiphilic Janus particles were fabricated comprising different responsive polymers on their surface, and their assembly was investigated depending on the pH value of the dispersion, the ionic strength, or the solvent. It was found that, under specific conditions, the Janus particles formed hierarchical chain-like structures in solutions, which were not observed in the case of the homogeneous particle mixtures. The obtained results indicate that the fundamental understanding of the Janus particle assembly mechanisms is crucial for the programmed formation of desired structures. In the third part of the work, we have focused on the applications of our developed hybrid hairy Janus particles and proposed two main directions that would benefit from the unique properties or architecture of the Janus particles. The first direction is based on the exploitation of the superior interfacial activity of the Janus particles and their use for interfacial catalysis. The second proposed direction for the application of Janus particles is based on their use as building blocks for functional structured surfaces. The prepared surfaces were thoroughly characterized and tested for their performance toward anti-icing as well as anti-fouling applications. Ultimately, the developed functional surfaces based on Janus particles as building blocks are very promising for their future application in the coating technology.

Spatial navigation is essential for everyday function. It is successfully achieved by combining internally generated information – such vestibular and self-motion cues (known as path integration) – with external sources of information such as visual landmarks. These multiple sources and sensory domains are often associated with uncertainty and can provide conflicting information. The key to successful navigation is therefore how to integrate information from these internal and external sources in the best way. Healthy younger adults do this in a statistically optimal fashion by considering the perceived reliability of a cue during integration, consistent with the rules of Bayesian integration. However, the precise impact of ageing on the component senses of path integration and integration of such self-motion with external information is currently unclear. Given that impaired spatial ability is a common problem associated with ageing and is often a primary indicator of Alzheimer’s disease, this thesis asks whether age-related navigational impairments are related to fundamental deficits in the components of path integration and/or inadequate integration of spatial cues. Part 1 focussed on how ageing impacts the vestibular, kinaesthetic and visual components of path integration during linear navigation in the real world. Using path reproduction, distance estimation and depth perception tasks, I found that older adults showed no performance deficits in conditions that replicated those of everyday walking when visual and self-motion cues were present. However, they were impaired when relying on vestibular information alone. My results suggest that older adults are especially vulnerable to sensory deprivation but that weaker sensory domains can be compensated for by other sensory information, potentially by integrating different spatial cues in a Bayesian fashion: where the impact of unreliable/diminished senses can be minimised. Part 2 developed the conclusions of Part 1 by testing younger and older adults’ integration of visual landmarks and self-motion information during a simple homing task. I investigated the hypothesis that the integration of spatial information from multiple sensory domains is driven by Bayesian principles and that old age may affect the efficiency and elasticity of reliability-driven integration. Younger and older participants navigated to a previously visited location using self-motion and/or visual information. In some trials there was a conflict of information, which revealed the relative influence of self-motion and visual landmarks on behaviour. Findings revealed that both younger and older adults integrated visual and self-motion information to improve accuracy and precision, but older adults did not place as much influence on visual information as would have been optimal. This may have been the result of increased noise in the underlying spatial representations of older adults. Furthermore, older adults did not effectively re-weight visual and self-motion cues in line with the changing reliability of visual information, suggesting diminished plasticity in the underlying spatial representations. However, further development of the testing paradigm would strengthen support for these findings. Together, the findings of Part 2 suggest that increased neural noise and the suboptimal weighting of spatial cues might contribute to the common problems with navigation experienced by many older adults. This thesis provides original evidence for age-related changes to multisensory integration of spatial cues. Path integration abilities are relatively preserved when older adults navigate linear paths in the real world, despite loss of vestibular function. However, navigation is affected by old age when the task becomes more complex. Multisensory integration of spatial cues is partially preserved but it is not fully efficient. I offer evidence that the navigational impairments common to old age are related to fundamental deficits in the components of path integration, task complexity, and suboptimal integration of spatial cues. Crucially however, path integration is preserved sufficiently in older adults that they are able to navigate in small scale with relative success.

We are providing the geophysical data used to develop a gravity validated 3D lithospheric configuration of the Caribbean and north South American plates. The sources of these data are described in Section 4 of this README. Republication of subsets of these data are with permission of the authors or allowed by the licences of the input data. This data repository contains the lithospheric layers of the gravity validated 3D structural and density model of the Caribbean and north South American plates. In this model, the integration of different publicly available geophysical datasets was made, after an interpolation to a homogeneous spatial resolution of 25 km was performed. The data repository also contains the average density of the crystalline crust obtained after forward modelling the gravity anomalies. Additionally, the rotation files of the GPlates reconstructions of the Caribbean Large Igneous Plateau (CLIP) back to 90 Ma are included. This kinematic analysis was based on different reconstructions previously published by other authors. Further information and citations are given on the README file associated to this data repository.

Eine Absenkung der Betriebstemperatur von Festoxidbrennstoffzellen (SOFCs) in den Bereich um 500 °C wird angestrebt um Anwendungsfelder wie Brennstoffzellengeneratoren für mobile Anwendungen zu erschließen. Jedoch weist yttriumstabilisiertes Zirkonoxid (YSZ), der nach aktuellem Stand der Technik verwendete Elektrolytwerkstoff, eine unzureichende ionische Leitfähigkeit in diesem Niedertemperaturbereich auf. Zwei Lösungsansätze können hier Abhilfe schaffen. Der erste, weitverbreitete Ansatz ist die Verwendung eines alternativen Elektrolytwerkstoffs mit höherer Leitfähigkeit. Ein Vergleich von in der relevanten Fachliteratur angegebenen Daten zeigt allerdings uneinheitliche Leitfähigkeitswerte der einzelnen Werkstoffe und deren Verhältnisse zueinander. Der zweite Ansatz ist eine Verringerung der Elektrolytdicke. Über Schleuderbeschichtung (engl: spin coating) können Schichtdicken von etwa 1 μm realisiert werden. Diese Herstellungsmethode ist sehr arbeitsintensiv, da mehrfache Durchläufe von Beschichtungszyklus, Trocknung und Wärmebehandlung notwendig sind. Zudem stellt eine weitere Reduzierung der Schichtdicke eine große Herausforderung dar. Ziel dieser Arbeit ist ein systematischer Vergleich der ionischen Leitfähigkeit der drei überwiegend verwendeten und kommerziell erhältlichen Elektrolytwerkstoffe. Diese sind YSZ, scandiumstabilisiertes Zirkonoxid (ScSZ) und gadoliniumdotiertes Ceroxid (GDC). Mittels elektrochemischer Impedanzspektroskopie (EIS) konnte gezeigt werden, dass GDC mit 5,8 x 10$^{-3}$ S cm$^{-1}$ eine höhere ionische Leitfähigkeit bei 500 °C aufweist als ScSZ (2,5 x 10$^{-3}$ S cm$^{-1}$) und YSZ (1,1 x 10$^{-3}$ S cm$^{-1}$). Diese Analyse erfolgte unter Berücksichtigung von Ausgangspulver, Herstellungsmethode und resultierender Mikrostruktur nach der Sinterung. In weiterführenden Versuchen wurde ein Prozessablauf für die Herstellung eines 5cm x 5cm GDC Elektrolyten über Siebdruck auf eine herkömmliche anodengestützte Zelle entwickelt. Nach der Sinterung bei 1400 °C für 5 Stunden wurde eine Elektrolytdicke von 3,5 μm erreicht, sowie eine ausreichende Luftdichtigkeit mit einer Leckrate von 3,54 x 10$^{-6}$ hPa dm$^{2}$ s$^{-1}$ cm$^{-2}$ ermittelt. Die elektrochemische Charakterisierung einer solchen Einzelzelle zeigte eine hohe Leistungsfähigkeit von 2A cm$^{-2}$ bei 750 °C und einer Zellspannung von 0,84 V (Kathodengas: Luft, Anodengas: 10% H$_{2}$O in H$_{2}$). Mittels EIS wurde ein ohmscher Widerstand von 125,2m$\Omega$ cm$^{2}$ bei 500 °C ermittelt. Der vorliegende Vergleich der ionischen Leitfähigkeiten kann als Referenz für weiterführende Arbeiten dienen und Hilfestellung bei der Auswahl eines geeigneten Elektrolytwerkstoffs für die jeweils angestrebte SOFC Anwendung leisten. Dies gilt insbesondere, wenn die Herstellung unterschiedlicher Schichtdicken berücksichtigtwerden soll. Diese Arbeit bietet somit eine solide Basis zur Weiterentwicklung, die in der zuvor publizierten Literatur durch teils widersprüchliche Angaben nicht gegeben war. Die erfolgreiche Entwicklung der dünnen und dichten GDC Elektrolytschicht zeigt die Anwendbarkeit von GDC auf üblichen SOFC Substraten und bestätigt die höhere Leistungsfähigkeit im Vergleich zu YSZ, während ein hoher Herstellungsaufwand für sub-μm Schichten vermieden wird.

An attempt is made for the first time to solve the quadratic and cubic model of magneto hydrodynamic Poiseuille flow of Phan-Thein-Tanner (PTT). Series solution of magneto hydrodynamic (MHD) flow is developed by using homotopy perturbation method (HPM). Results are presented graphically and the effects of non-dimensional parameters on the flow field are analyzed. The results obtained reveals many interesting behaviors that warrant further study on the equations related to non-Newtonian fluid phenomena.

The angular distributions of prompt-fission γ-rays with respect to thedirection of fission fragments in the monochromatic “warm” neutron induced fissionof 235U have been studied. The fragments were detected with low-pressure positionsensitive multi-wire proportional counter and the gamma-rays with a plastic scintillators. The time-of-flight method is used to discriminate prompt neutrons and promptγ-rays of fission. From the measured angular distributions with respect to the directionof the selected fragments, the value of the laboratory anisotropy has been found to be15 % in comparison to the value obtained in the perpendicular direction. The measurements indicate the existence of a significant anisotropy of emission of the γ-rays in theemitting-fragment system, suggesting the presence of significant angular momenta ofthe fragments correlated with the fission axis, which also lead to an enhanced emissionof the γ-rays. Moreover, the article includes a new technique for measuring and correcting the obtained angular distribution, in the case of when plastic scintillators havedifferent threshold levels for detection of γ-rays. Romanian Reports in Physics 75(1), 202 pp. (2023).

Abstract: In this paper, based on Jumarie type of Riemann-Liouville (R-L) fractional derivative, the exact solution of linear system of fractional differential equations with constant coefficients is obtained. A new multiplication of fractional analytic functions plays an important role in this paper. In addition, we also provide some examples to illustrate the application of our results. In fact, our results are generalizations of these results in ordinary differential equations. Keywords: Jumarie type of R-L fractional derivative, exact solution, linear system of fractional differential equations with constant coefficients, new multiplication, fractional analytic functions. Title: Exact Solution of Linear System of Fractional Differential Equations with Constant Coefficients Author: Chii-Huei Yu International Journal of Mechanical and Industrial Technology ISSN 2348-7593 (Online) Vol. 10, Issue 2, October 2022 - March 2023 Page No: 1-7 Research Publish Journals Website: www.researchpublish.com Published Date: 02-December-2022 DOI: https://doi.org/10.5281/zenodo.7391108 Paper Download Link (Source) https://www.researchpublish.com/papers/exact-solution-of-linear-system-of-fractional-differential-equations-with-constant-coefficients International Journal of Mechanical and Industrial Technology, ISSN 2348-7593 (Online), Research Publish Journals, Website: www.researchpublish.com

The field of uncharged phosphorus superbases was expanded to include several new mono- and bisphosphazenyl phosphines. These novel bases have been systematically analyzed according to their basicity, nucleophilicity, chemical stability, donor capabilities and coordination behavior. They complement the missing link between extremely basic trisphosphazenyl phosphines and traditional tertiary phosphines by combining the stability and steric properties of tertiary phosphines like PtBu3 with the extreme donor capabilities of phosphazenyl phosphines. The aforementioned parameters that were established during this work allow the easy classification of newly synthesized bases. Several applications of these bases were presented, as ligands in transition metal catalysis as well as organocatalysts in a variety of transformations.

As data gathering technologies are permeating various corners of our lives, a number of stakeholders are attempting to map, track, analyse and define what is happening to our identity, our privacy, or our ways of being social. As notions like privacy, anonymity, data, unlinkability, or pseudonymity are being defined, many of these definitions, while sounding almost the same, shift meaning from discipline to discipline, from context to context, and from one political agenda to the other. In this interview with Marit Hansen, one of the most influential activists for data protection regulation in Germany, and the head of the Independent Centre for Data Protection (ULD) and the Data Protection Commissioner of Schleswig-Holstein, Hansen highlights the way in which her computer science discipline defines its terms and working categories, in a rapidly changing landscape of data gathering technologies. The interview draws heavily from her (co-authored with Andreas Pfitzmann) seminal paper in the computer science field around privacy, anonymity and ‘identity management,’ titled ‘A terminology for talking about privacy by data minimization: Anonymity, unlinkability, undetectability, unobservability, pseudonymity, and identity management’.