Application of the Christiansen-Shelyubskii method to determine homogeneity and refractive index of industrial glasses

The Christiansen-Shelyubskii method has been applied to determine the homogeneity of both colorless and colored technical glasses. It could be confirmed that this method is sufficiently sensitive to changes by the melting process of flat, container and special glasses. The homogeneity factor, which essentially is the standard deviation of the refractive index, can be obtained with a precision of about ±5 %. The measurement simultaneously delivers the mean refractive index with high accuracy. This property possibly could be used to substitute density measurements to control the constancy of glass composition. The Christiansen-Shelyubskii method can be standardized and highly automated. About 15 samples can be measured per day. Thus it shows all features of a method to be used for industrial quality control

Suppression and amplification of phonon sidebands in transition metal dichalcogenides by optical feedback

Transition metal dichalcogenides (TMDCs) combine both strong light-matter-interaction and strong Coulomb-interaction for the formation of optically excitable excitons. Through radiative feedback control, a mechanism to control the linewidth can be applied, which modifies optical transition spectra. Here, we extend these investigations to the absorption spectra of TMDCs in a variety of geometries with respect to non-Markovian exciton-phonon-scattering contributions. Our approach is based on the self consistent solution of the microscopic Bloch equations and the macroscopic solution of the wave equation. We discuss the formation of a phonon sideband for MoSe$_2$ embedded in SiO$_2$, and two setups for enhancing or suppressing the phonon sideband in the spectrum

News on Demand

: This paper is describing a solution for an interactive video service in the World Wide Web. It has a look at creating an information retrieval system based on television and German video text. The service aims at presentation in the World Wide Web . The paper has a look on all components of the service. It starts with a brief look on the service as it appears to the client. The following part deals with obtaining traditional media and to process them into a format for later usage of a teleservice. In the following there are reflections on possible client concepts, especially methods to integrate real time video into Webpages. Video transmission also makes the main issues for the server and communication between client and server. After an explanation of our implementation the paper ends with some conclusions about experiences and future work. Keywords: Multimedia, Teleservices, WWW, Video, Stream-protocols 1 Introduction In the near future bandwidth of Internet-Connections will be w..

Influence of antimony oxide on the properties of YBa2Cu3O7-x superconductors prepared by melt quenching

The potential usefulness of glass-technological procedures to prepare oxidic high-temperature superconductors is well-known. Samples in the system Y-Ba-Cu-O have been produced by a melt process and subsequent annealing steps. Antimony oxides have been added to the base system and their influence on the properties of the products has been studied. The samples have been analyzed by X-ray diffraction and differential thermogravimetry as well as by electrical resistance measurements. With the addition of antimony oxides the type and quantities of the crystalline phases changed both in the quenched samples and in the samples annealed at temperatures above 900 °C and also the density increased. It was found that the samples containing antimony oxides as well as the samples of the base system become superconductors at a temperature higher than the liquid nitrogen temperature. Only the annealing time is much less than that for the pure superconductor