Publikationen

Halbedel, Bernd; Kontogeorgakos, Apostolos
Ferrimagnetic ceramic adsorbents for cleanup of H 2 S from exhaust gases. - In: China particuology, ISSN 2210-4763, Bd. 5 (2007), 1/2, S. 156-161

Adsorbents that exhibit magnetic properties in addition to other required process relevant characteristics open up new perspectives for the dry reduction and/or elimination of H2S and other sulfur compounds from exhaust gases. They ensure the elimination of the loads from exhaust gases by coatings and also a magnetically assisted and stabilized fluidization by applying of an externally generated magnetic field. - In the present paper the feasibility of the sorptive functionality of porous, ceramic, ferrimagnetic beads is evaluated by sol-gel coatings of zinc oxide without the formation of Zn-Fe-oxides and without the considerable decrease of the available pore volume. The results of the materials characterization by SEM, Auger electron spectroscopy, X-Ray and mercury-porosity measurements and for the loading capacity in a model gas of the composition H2S/N2 are presented and discussed. The resulting H2S loading of the functionalized beads is above ten times larger of that of the starting materials.

http://dx.doi.org/10.1016/j.cpart.2007.01.002

Hamann, Bernd; Schadewald, Uwe; Ludwig, Yvonne; Ertel-Ingrisch, Werner; Pothérat, Alban
Kristallisation von Bariumhexaferrit in starken magnetischen Gleichfeldern : Abschlussbericht der Nachwuchsforschergruppe Electromagnetic Processing of Materials (EPM). - Ilmenau : Techn. Univ.. - 1 CD-ROM

Schadewald, Uwe; Halbedel, Bernd; Romanus, Henry; Hülsenberg, Dagmar
New results of the crystallization behaviour of hexagonal barium ferrites from a glassy matrix. - In: Information technology and electrical engineering - devices and systems, materials and technologies for the future, (2006), insges. 8 S.

http://www.db-thueringen.de/servlets/DocumentServlet?id=13512

Halbedel, Bernd; Krieger, Uwe
Modification of iron oxide containing glass melts and their crystallization behaviour under an inhomogeneous, low AC magnetic field. - In: Information technology and electrical engineering - devices and systems, materials and technologies for the future, (2006), insges. 10 S.

In terms of electromagnetic processing of materials the interactions of high magnetic fields ( >> 1 T) with solidified structures of metals, alloys and ceramics are well known and applied for crystal orientation and phase transformation, e. g. [1], [2] and [3]. In contrast the influence of an inhomogeneous low magnetic field on melts with a high content of paramagnetic ions is rarely investigated. - In this study an inhomogeneous AC magnetic field with a low flux density (up to 55 mT) was imposed on a melt containing 33.84 wt% iron oxide. The changes in the material properties of the solidified melts were investigated due to the interaction with the magnetic field gradient. The outcome of this is the effect of the magnetic gradient force acting on the ions in such melts. It enables the feasibility to influence the phase segregation and the valence of the iron ions in the melt as well as the following crystallization without any mechanical contact and independent on other process parameters. That creates new innovative possibilities of electromagnetic processing of magnetic materials in order to adjust their properties.

http://www.db-thueringen.de/servlets/DocumentServlet?id=13893

Ludwig, Yvonne; Hülsenberg, Dagmar;
Crystallization of barium hexaferrite inside high magnetic DC fields. - In: Proceedings, (2006), S. 595-598