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- ItemNew Developments in the Field of Glass Ceramics(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2003) Pannhorst, Wolfgang[no abstract available]
- ItemAccurate measurement of absorption spectra and refractive index of glass by Spectrophotometry(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) van Nijnatten, Peter A.The experimental methods for determining optical constants like refractive index and absorption coefficient often require specialized equipment. An Instrument that is standard equipment in most laboratories where optical materials are being characterized is the spectrophotometer. This type of Instrument is widely used for the measurement of reflectance and transmittance spectra at wavelengths ranging from 200 nm up to 50,000 nm. The paper aims to present a state-of-the-art overview of methods for determination of the optical constants of glass by Spectrophotometry. Examples are given for various types of glasses and applications under room temperature as well as elevated temperatures.
- ItemCorrosion of Glass(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) Helebrant, A.; Jiřička, A.; Jiřičková, JThe paper reviews the different models describing interaction between glasses and aqueous solutions. It is shown the development of kinetic and thermodynamic models (Rana & Douglas, HIaváč & Matěj, Isard et al., Boksay & Doremus, Strachan, Grambow, Conradt, Aagaard & Helgeson). The models are compared from the point of view of different mechanisms and partial processes considered during model development. Model based on combination of Boksay & Doremus and Strachan models is shown, considering the glass corrosion as a combination of three simultaneous processes: 1. Glass matrix dissolution with two subsequent steps (surface reaction and surface reaction products transport through the precipitated layer and/or through Solution layer adjacent to the glass surface) 2. Leaching of moveable ions (A⁺) due to interdiffusion of HsO⁺ - A⁺ 3. Precipitation of dissolved glass components and/or Solution components on the glass surface. Finally, the outlook for future development of glass corrosion modelling is suggested, based on combination of Boksay & Doremus, Strachan, Conradt and Aagaard & Helgeson approach.
- ItemStudy of Sodium-Zinc Borophosphate Glasses(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) Kodelka, L.; Mošner, P.; Jirák, J.; Jäger, C.; Zeyer-Düsterer, M.[no abstract available]
- ItemMicro-and Nanostructured Optics(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2003) Wittig, Lars-Christian; Kley, Ernst-Bernhard; Tünnermann, Andreas[no abstract available]
- ItemStructure and Viscosity of RE-Oxynitride Glasses(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) Lofaj, F.; Dorčáková, F.; Dolekcekic, E.; LeFloch, M.; Rouxel, T.; Hoffmann, M. J.; Hampshire, S.[no abstract available]
- ItemHybrid diffractive-refractive optics: opportunities and technologies to realize complex optical imaging Systems(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2003) Brunner, R.; Steiner, R.; Dobschal, H.-J.; Rudolf, K.[no abstract available]
- ItemVerification of Released Energy in the Models Furnaces by Means of Thermo Vision(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) Lisý, A.; Hamáček, L.The distribution of released electric energy has been investigated on the two dimensional mathematical model of a full electric melting tank. The power fields were calculated for two chosen variants of electrode connection to the supply source. The physical model of heating system made from an electro-conductive foil and the method of monitoring released energy between electrodes by a thermo vision camera were used for verification of the calculated results.
- ItemChemical durability of sodium disilicate glasses in aqueous salt solutions(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) Roggendorf, H.; Trempler, J.; Böschel, D.; Becker, C.; Michler, G.H.[no abstract available]
- ItemLow Pressure evaporation from boron containing glass melts by the transpiration method(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) Dacko, Dawid; Wilsmann, Wolfgang; Conradt, ReinhardGlass melting is a well-established process, but it does not seem to be well understood under low-pressure conditions. Melting under low pressure has been suggested as a potential support of the refining process. This makes sense only if the evaporation form the glass melt is kept within acceptable limits. Α transpiration apparatus equipped for operation at low pressure, termed low pressure transpiration method, was used to investigate the evaporation from boron containing glass melts. We obtained information on the weight loss as a function of temperature, time, and pressure. We investigated an alkali borosilicate glass with acomposition in mol % of: 79SiO₂,7 Na₂O, 10 B₂O₃, 3 AI₂O₃, 1 minor constituents. At the beginning of glass melting, the evaporation mechanism was detected as surface controlled. Later, a diffusion controlled stationary behaviour was observed. The ratio of sodium oxide to boron oxide in the evaporated gas as determined by chemical analysis ranged from 1.25 to 1.4.