22,458 research outputs found
India and South Asia in Germany : the world according to GNARP: prospects for transatlantic library partnership in the digital age ; 6th scientific symposium Frankfurt a. M.
Seit 2005 ist die Bibliothek des Südasien-Instituts in Kooperation mit der UB Heidelberg Trägerin des DFG-geförderten Sondersammelgebiets Südasien. Damit hat sie von der UB Tübingen ein traditionsreiches Sondersammelgebiet übernommen, dessen Geschichte bis ins Jahr 1949 zurückreicht. Der Vortrag wird zum Einen einen kurzen Überblick über den historischen Kontext des SSG Südasien geben und zum Anderen über Neuentwicklungen, wie z.B. die Virtuelle Fachbibliothek Südasien, die in den letzten zwei Jahren an der Bibliothek des Südasien-Instituts aufgebaut wurde. Vor diesem Hintergrund soll vor allem das Kooperationspotential im Bereich digitaler Informationsressourcen beleuchtet werden
A geometrically controlled rigidity transition in a model for confluent 3D tissues
The origin of rigidity in disordered materials is an outstanding open problem
in statistical physics. Previously, a class of 2D cellular models has been
shown to undergo a rigidity transition controlled by a mechanical parameter
that specifies cell shapes. Here, we generalize this model to 3D and find a
rigidity transition that is similarly controlled by the preferred surface area:
the model is solid-like below a dimensionless surface area of
, and fluid-like above this value. We demonstrate that,
unlike jamming in soft spheres, residual stresses are necessary to create
rigidity. These stresses occur precisely when cells are unable to obtain their
desired geometry, and we conjecture that there is a well-defined minimal
surface area possible for disordered cellular structures. We show that the
behavior of this minimal surface induces a linear scaling of the shear modulus
with the control parameter at the transition point, which is different from the
scaling observed in particulate matter. The existence of such a minimal surface
may be relevant for biological tissues and foams, and helps explain why cell
shapes are a good structural order parameter for rigidity transitions in
biological tissues.Comment: 6 pages main text + 13 pages appendix, 3 main text figures + 6
appendix figure
Parting layers, ash trays and Ramesside glassmaking: an experimental study
A series of glassmaking and glass colouring
replication experiments was undertaken in order to
test some of the current hypotheses concerning Late
Bronze Age glass production at Qantir-Piramesses.
These were based on the model of glassmaking
developed in this volume, and aimed in particular to
test the behaviour of the parting layer and the local
ceramic under the proposed chemical and thermal
conditions. Modern ash trays made out of Egyptian
Nile silt clay were used as proxies for LBA reaction
vessels and crucibles, and both raw glass and
coloured glass ingots were produced in them. This
experimental study, based on detailed observation
and technical studies of archaeological samples from
Qantir-Piramesses, not only provides material
readily comparable to the archaeological finds, but
brings to the forefront practical issues concerning the
nature of the parting layer, its application, the
melting procedures, the re-use of crucibles, and
indirect evidence of primary production, such as the
impact of sodium chloride, a major component of
plant ashes, on the ceramic. Although this string of
experiments does not fully replicate LBA
glassmaking technology, much information was
obtained and further areas of ambiguity identified
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