3,472 research outputs found
Improving an inequality for the divisor function
We improve using elementary means an explicit bound on the divisor function
due to Friedlander and Iwaniec. Consequently we modestly improve a result
regarding a sieving inequality for Gaussian sequences.Comment: 8 pages, to appear in Bull. AustM
Optical properties of bialkali photocathodes
The optical properties of the `bialkali' KCsSb and RbCsSb photomultiplier
cathodes have been experimentally investigated in the visible range. The
measurements carried out include the absolute reflectance at near-normal
incidence, the polarization-dependent relative reflectance at various angles
and the change in polarization upon reflection from the photocathode. These
experimental inputs have been combined with a theoretical model to determine
the complex refractive index of the photocathodes in the wavelength range 380
to 680 nm and their thickness. As a result of this work, we derive a model
which predicts the fraction of light impinging on a photomultiplier tube that
is reflected, absorbed or transmitted, as a function of wavelength and angle,
and dependent on the medium to which the photomultiplier is coupled.Comment: 51 pages (double spacing), 16 figures, submitted for publication in
NIM
Innovative Service-Based Business Concepts for the Machine Tool Building Industry
Organised by: Cranfield UniversityDuring the last decade, machine tool building companies have been forced to put innovative offers on the
market. Due to the technical features of their products and the prevailing organizational structures in this
sector, especially product-service systems are a promising way of creating a unique selling point. In this
paper, potential new business concepts for machine tool builders will be presented which aim at fulfilling
basic customer needs like the increase in quality, flexibility, productivity and the reduction of lead times,
costs and risks. For the implementation of these product-service systems, practical examples are given.Mori Seiki – The Machine Tool Compan
Germanene: a novel two-dimensional Germanium allotrope akin to Graphene and Silicene
Using a gold (111) surface as a substrate we have grown in situ by molecular
beam epitaxy an atom-thin, ordered, two-dimensional multi-phase film. Its
growth bears strong similarity with the formation of silicene layers on silver
(111) templates. One of the phases, forming large domains, as observed in
Scanning Tunneling Microscopy, shows a clear, nearly flat, honeycomb structure.
Thanks to thorough synchrotron radiation core-level spectroscopy measurements
and advanced Density Functional Theory calculations we can identify it to a
xR(30{\deg}) germanene layer in coincidence with a
xR(19.1{\deg}) Au(111) supercell, thence, presenting the
first compelling evidence of the birth of a novel synthetic germanium-based
cousin of graphene.Comment: 16 pages, 4 figures, 1 tabl
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