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In this article, we study the problem (sometimes called the Berger-Nirenberg problem) of prescribing the curvature on a Riemann surface (that is on an oriented surface equipped with a conformal class of Riemannian metrics). ...
H-1 NMR studies of thiophenol capping groups on cadmium sulfide nanocrystals demonstrate that the coverage of the capping molecule depends on the size of the nanocrystal. Data are presented which show that as the size of the nanocrystal increases, the cove ...
In this paper, we prove that if f is a conformal map between two Riemannian surfaces, and if the curvature of the target is nonpositive and less than or equal to the curvature of the source, then the map is contracting. ...
We study sequences of metrics on a compact surface with bounded area and curvature and I prove that if the conformalstructure of these metrics remains bounded, then either the sequence contains a convergent subsequence, or there exists a point at which a c ...
Let S and S′ be compact Riemann surfaces of the same genus g (gge2) endowed with the Poincaré metric of constant negative curvature -1. par The authors show that for every epsilon>0, there exists an integer m=m(g,epsilon) with the property: Assum ...
We study conditions under which a point of a Riemannian surface has a neighborhood that can be parametrized by polar coordinates. The point under investigation can be a regular point or a conical singularity. We also study the regularity of these polar coo ...
We study the problem of prescribing the curvature on Riemann surfaces. We extend some results that are classical in the compact case to the non compact case. ...
We study the Berger-Nirenberg problem on surfaces with conical singularities, i.e, we discuss conditions under which a function on a Riemann surface is the Gaussian curvature of some conformal metric with a prescribed set of singularities of conical types. ...
Contact potential difference (CPD) measurements using a Kelvin probe coupled with synchrotron radiation are used to investigate the surface photovoltage (SPV) induced by synchrotron radiation at GaAs surfaces. A large and quasi-permanent SPV is found at su ...
