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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.

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.

The species Acrocinus longimanus, popularly called harlequin beetle, is one of the most emblematic beetles of Neotropical fauna. In the presente study we report on the first record of Acrocinus longimanus (Linnaeus, 1758) in the city of Montes Claros, Minas Gerais, Brazil. The specimen was registered in November 2018 in the urban zone of Montes Claros in a residential and commercial area. This is the first record of Acrocinus longimanus in the city of Montes Claros, Minas Gerais and represents only the fourth record of the species in the Brazilian Cerrado region. Our study reinforces the occurrence of this species in the Brazilian Cerrado and the use of urban areas by this longhorned beetle.

Control techniques for proton exchange membrane fuel cells (PEMFC) can be improved with sophisticated modeling tools. Existing dynamic PEMFC models are still hampered by a tradeoff between computational speed and simulation precision. To resolve this problem, a novel two-phase flow discretized PEM fuel cell model is developed in this thesis.Utilizing an ex-situ optical visualization experimental setup, the influence of current density on the flow of liquid water in the flow field is analyzed. Testing results reveal that with external current, there is an increase in the global water surface area. In addition, the unequal current distribution modifies the water coverage ratio distribution. To reveal the mechanisms and effects of these occurrences, a numerical study of the influence of polarization on the flow of liquid water inside the gas diffusion layer (GDL) is conducted subsequently. Using a two-dimensional numerical stochastic model and a volume of fluid (VOF) simulation technique, this study demonstrates that the polarization force allows liquid water to permeate the GDL at lower internal pressures. Based on the Washburn equation, the modified Washburn equation (MWE) is created to parameterize the polarization impact of liquid water on its breakthrough pressure through the GDL.The MWE is included in a new two-phase flow discrete PEMFC model. Combining a Lattice Boltzmann Method (LBM) two-phase flow gas channel model and a discrete solid body model, the newly created model can simulate the non-uniform active area loss produced by liquid water inside the flow field and its influence on the fuel cell performance. The proposed model is then implemented in Matlab and evaluated with experimental data from the scientific literature at the cell and stack levels. The model predicts the polarization curve with more than 98% accuracy in simulations.The two-phase flow LBM model is simplified to improve the model's computational performance and engineering application possibilities. The model is then utilized to evaluate the impacts of external variables and operational settings on a Ballard Mark 9SSL fuel cell stack, showing considerably reduced processing time. Due to its real-time capabilities, the newly developed model can be easily integrated into existing 0/1-D commercial vehicle simulation tools, such as GT-SUITE, and allows the development of highly realistic dynamic models and control systems for fuel cell automobiles. Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2023; Aachen : RWTH University Aachen 1 Online-Ressource |b Illustrationen, Diagramme (2023). = Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2023 Published by RWTH University Aachen, Aachen