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- ItemOn-line determination of the iron concentration in industrial amber glass melts(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1995) Müller-Simon, Hayo; Mergler, Kurt WilhelmA sensor has been developed in order to measure the concentration of polyvalent elements on-hne in industrial glass melts. The sensor has been tested on iron in an amber glass melt. A method has been developed in order to determine the area of the measuring electrode, which can change due to glass level variation. The accuracy of the iron determination by means of the voltammetric sensor has been found half the accuracy of x-ray fluorescence analysis.
- ItemOn the interaction between oxygen, iron and sulfur in industrial glass melts(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1994) Müller-Simon, HayoThe oxidation state of iron in industrially molten glasses has been investigated in the cold glass and related to the oxygen activity in the glass melt. The prediction of the oxidation state of iron in the cold glass from the measured oxygen activity in the glass melt is disturbed in such a way that in oxidized molten glasses the Fe²⁺ content and in amber glasses the Fe³⁺ content increase during cooling. This behavior can be explained by an interaction due to the oxidation reactions of sulfur known from the literature during cooling. The reaction constants result in electrochemical standard potentials which agree with voltammetric studies.
- ItemSelenium flow in the melting of flint glass Containers(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1996) Müller-Simon, Hayo; Kirchner, Ulrich[no abstract available]
- ItemPractical strength of glass containers. Part 2. Influence of handling(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1994) Wagner, Jörg; Müller-Simon, Hayo; Lenhart, ArminThe practical strength of container glass depends not only on the stress distribution at the surface, but also on the type and distribution of surface defects. After the elimination of the influence of the container shape by means of finite element methods, different types of defect show a different behaviour in the Weibull plot. This behaviour can be used to compare different handling materials. The materials used at the cold end cause no measurable weakening of the strength. A special type of defect could be associated with the transfer conveyour belt. Carbon and brass were compared as deadplate materials without finding a specific influence on the container strength.
- ItemApplication of oxygen sensors in industrial glass melting tanks(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1996) Baucke, Friedrich G. K.; Werner, Ralf D.; Müller-Simon, Hayo; Mergler, Kurt WilhelmΑ comparative study of electrochemical oxygen sensors for glass melts employing zirconia solid electrolytes developed by Schott Glaswerke and by the HVG is reported. The sensors applied in a feeder Channel of a melting tank producing green glass yielded slightly different but reproducible results despite different constructions. The zirconia reference electrodes achieved more than one year active lifetime at 1200°C. Their potentials directly compared over extended periods agreed within less than 3 mV. The potential differences of the platinum measuring electrodes were traced to temperature gradients. Newly installed platinum electrodes show "induction periods" caused by convectional and diffusional equilibration of adhering surface with bulk melt. Unexpected sudden oxygen inhomogeneities of the melt were detected and explained.
- ItemPractical strength of glass containers : Part 1. Influence of the type of defect(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1994) Müller-Simon, Hayo; Wagner, Jörg; Lenhart, ArminThe practical strength of container glass depends not only on the stress distribution at the surface, but also on the type and distribution of surface defects. After the elimination of the influence of the container shape by means of finite element methods, different types of defect show a different behaviour in the Weibull plot. Especially seeds and blisters are shown to be twice as dangerous as inhomogeneides caused by handling materials. The accuracy of the stress determination is limited, thus, an identification of different types of inhomogeneities from the Weibull plot is not possible under the present conditions.
- ItemElectron exchange reactions between polyvalent elements in soda-lime-silica and sodium borate glasses(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1996) Müller-Simon, HayoIn oxidic glasses the redox State of polyvalent elements is determined by the oxygen partial pressure with which the melt is in equilibrium. However, if a second polyvalent element is introduced the redox ratios at a given oxygen pardal pressure change for both elements. This interaction is interpreted in terms of electron exchange reactions during cooling. The direcdon of the electron exchange and the amount of exchanged electrons are calculated from the Standard reaction enthalpy and Standard reaction entropy of the involved polyvalent elements. Oxygen balance calculations are carried out based on literature data available for iron/chromium and iron/manganese interaction in soda-lime-silic a glasses and cerium/manganese interaction in sodium borate glasses. The iron/ chromium and iron/manganese interaction fmishes already at high temperatures. In that case the amount of exchanged electrons can be calculated from stoichiometric considerations. The cerium/manganese couple shows a typical freezing-in behavior in sodium borate glass during cooling. The freezing-in temperature can be associated with the distance of the interacting ions.