An introduction to endoreversible thermodynamics

Reversible thermodynamic processes are convenient abstractions of real processes, which are always irreversible. Approaching the reversible regime means to become more and more quasistatic, letting behind processes which achieve any kind of finite transformation rate for the quantities studied. On the other hand studying processes with finite transformation rates means to deal with irreversibilities and in many cases these irreversibilities must be included in a realistic description of such processes. Endoreversible thermodynamics is a non-equilibrium approach in this direction by viewing a system as a network of internally reversible (endoreversible) subsystems exchanging energy in an irreversible fashion. This material provides an introduction to the subject

Endoreversible Thermodynamics: A Tool for Simulating and Comparing Processes of Discrete Systems

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Endoreversible thermodynamics is concerned with reversible sub-systems that are in irreversible interaction with each other. Consequently, endoreversible thermodynamics represents the analogue for discrete systems to the local equilibrium hypothesis in continuum thermodynamics. Here a real cyclic 2-reservoir process is simulated by different endoreversible model processes. Simulation means that the simulating process has the same net heat exchanges, cycle time, power, entropy production, and efficiency as the original one. By introducing process-independent simulation parameters as constraints for the irreversible interaction, a family of comparative endoreversible processes is generated including the simulation of the original process. This procedure allows the process parameters of the family of comparative processes to be compared to those of the original one. The fraction “power of the real process over the maximal power inbetween the comparative family” is introduced as a parameter describing the process excellence

Entwicklung von neuen Sensorkonzepten und Untersuchungen an strahlenharten Siliziumstreifensensoren für CMS am Large Hadron Collider in der Hochluminositätsphase

Mit dem geplanten Upgrade des LHC müssen auch die Experimente aufgewertet werden. Für den CMS Detektor wird daher ein neuer Spurdetektor benötigt. Dafür wurden neuartige Sensorkonzepte entwickelt und untersucht. Zum einen wurden die von der CMS Upgrade Gruppe gegebenen Anforderungen an ein neues Sensorkonzept erfüllt und sogar übertroffen, und zum anderen wurden Untersuchungen an strahlenharten Siliziumstreifensensoren durchgeführt, um das am besten geeignete Material zu finden

Drag on spheres in micropolar fluids with non-zero boundary conditions for microrotations

This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The Stokes formula for the resistance force exerted on a sphere moving with constant velocity in a fluid is extended to the case of micropolar fluids. A non-homogeneous boundary condition for the micro-rotation vector is used: the micro-rotation on the boundary of the sphere is assumed proportional to the rotation rate of the velocity field on the boundary.Peer Reviewe

Deutschland: Region Hochrhein-Bodensee

Regionale Entwicklungsprozesse in der Region Hochrhein-Bodensee sind immer auch grenzüberschreitende Entwicklungsprozesse. Da die für den eigenen nationalen Raum verfügbaren Planungsinstrumente hier an reale Grenzen stoßen, müssen Strategien entwickelt werden, um das Denken und Handeln über Grenzen zu schärfen. In den vergangenen Jahren versuchte die Regionalplanung daher immer wieder grenzüberschreitende Planungsprozesse auszulösen. Im folgenden Beitrag wird diese Entwicklungsstrategie an zwei Beispielen beleuchtet. Ziel des deutsch-schweizerischen Entwicklungsprojektes "Strukturmodell Hochrhein" war es, vom grenzüberschreitenden Informationsaustausch hin zur gemeinsamen Erarbeitung konkreter Raumvorstellungen zu kommen. Mit der grenzüberschreitenden Testplanung "Langfristperspektiven für eine integrierte Raum- und Eisenbahnentwicklung am Hochrhein und Oberrhein" gelang es, zusammen mit den regional verantwortlichen Akteuren einen Beitrag zu leisten und den Ausbau der Rheintalbahn im Bereich der trinationalen Agglomeration Basel wesentlich zu beeinflussen. Es zeigt sich, dass raumplanerisches Einmischen Motor für Entwicklungsprozesse ist - in der Region Hochrhein-Bodensee ganz besonders für die Gestaltung grenzüberschreitender Entwicklungsprozesse.In the High Rhine - Lake Constance region regional development processes are always also cross-border development processes. As the planning instruments available in national space are restricted by real borders in this area, it is necessary to develop strategies to sharpen cross-border thinking and action. In recent years regional planning has therefore repeatedly attempted to initiate cross-border planning processes. The following discussion uses two examples to shed light on this development strategy. The aim of the German-Swiss development project “High Rhine structure model” was to progress from cross-border information exchange towards the joint preparation of concrete spatial visions. The cross-border test planning “Long term perspectives for integrated spatial and railway development on the High Rhine and Upper Rhine”, together with regionally responsible actors, was able to successfully contribute towards significantly influencing the extension of the Rhine Valley Railway in the tri-national area of the Basel agglomeration. It was demonstrated that spatial planning involvement is an engine for development - in the High Rhine - Lake Constance region particularly for the shaping of cross-border development processes

The onset of flysch sedimentation in the Kaoko Belt (NW Namibia) – Implications for the pre-collisional evolution of the Kaoko–Dom Feliciano–Gariep orogen

Detrital zircon provenance study of a metamorphosed sedimentary succession in the eastern part of the Kaoko Belt in Namibia has revealed two distinct sources for the Neoproterozoic sedimentation along the southwestern Congo Craton margin. The lower part of the succession shows detrital zircon ages consistent with erosion of Paleoproterozoic basement of the Congo Craton with an inferred Mesoproterozoic volcano-sedimentary cover. Within the middle part of the succession, which includes glaciogenic sediments correlated with the Sturtian (717–660 Ma) glaciation, the Mesoproterozoic zircon grains disappear and the signal is dominated by ages known from the Congo Craton basement. The sedimentation in these parts of the succession is interpreted as related to the early Neoproterozoic rifting. The sedimentary rocks in the top part of the profile contain only subordinate proportion of the Paleoproterozoic–Archaean zircon grains and the populations are dominated by three age groups of ca. 1.0–1.2 Ga, ca. 800–750 Ma and ca. 650 Ma, consistent with erosion of the Punta del Este–Coastal Terrane exposed in the centre of the Kaoko–Dom Feliciano–Gariep orogen. An associated glaciogenic horizon interpreted as reflecting the Marinoan (645–635 Ma) glaciation constrains the sedimentation in the upper part of the succession and suggests a short time span between the high-grade metamorphism/magmatism in the Punta del Este–Coastal Terrane and its exhumation. Sedimentary rocks with such detrital zircon pattern appear also in the Damara and Gariep belts. Their source in the western part of the Kaoko–Dom Feliciano–Gariep orogen suggests that they represent an early orogenic flysch that originated during early collision in the western part of the orogen. The short time span between the metamorphism/magmatism in the Punta del Este–Coastal Terrane and deposition of the early orogenic flysch derived from it suggests that the Coastal Terrane was never separated from the Congo Craton by an oceanic domain. The estimated time span between the end of lithospheric stretching and sedimentation of the early flysch suggests that the hypothetical Adamastor Ocean separating the western and eastern forelands of the Kaoko–Dom Feliciano–Gariep orogen must have been small.acceptedVersio