AlGaN/GaN-heterostructures on (111) 3C-SiC/Si pseudo substrates for high frequency applications. - In: Thin solid films, ISSN 1879-2731, Bd. 520 (2011), 1, S. 491-496
http://dx.doi.org/10.1016/j.tsf.2011.07.003
Glow discharge optical emission spectroscopy for accurate and well resolved analysis of coatings and thin films. - In: Thin solid films, ISSN 1879-2731, Bd. 520 (2011), 5, S. 1660-1667
http://dx.doi.org/10.1016/j.tsf.2011.07.058
Epitaxial graphene three-terminal junctions. - In: Applied physics letters, ISSN 1077-3118, Bd. 99 (2011), 17, S. 173111, insges. 3 S.
http://dx.doi.org/10.1063/1.3653469
Vertical design of cubic GaN-based high electron mobility transistors. - In: Journal of applied physics, ISSN 1089-7550, Bd. 110 (2011), 11, 114501, insges. 8 S.
https://doi.org/10.1063/1.3663364
Effect of titanium ion substitution in the barium hexaferrite studied by Mössbauer spectroscopy and X-ray diffraction. - In: Hyperfine interactions, ISSN 1572-9540, Bd. 202 (2011), 1/3, S. 97-106
A series of M-type barium hexaferrite has been synthesized in a glass melt by partially substituting the Fe2O3 with TiO2 for investigation of their structure. The glass melt has the basic composition (mol%): 40 BaO + 33 B2O3 + (27-x) Fe2O3 + x TiO2 with x = 0, 3.6, 5.4 and 7.2 mol% TiO2. The substituted ferrites were studied by means of X-ray diffraction, Mössbauer spectroscopy and vibration sample magnetometer. X-ray diffraction studies revealed that not all samples have a single ferritic phase, a small second phase corresponding to BaTi6O13 was also observed to form. The Mössbauer spectra changed from magnetically ordered (x = 0) to magnetically ordered with strong line broadening. Moreover, the broadening increases with TiO2 content. The Mössbauer parameters suggested that Ti4+ occupies the 2a and 12k crystal sites, and the Ti4+ substitution on the 2b and 4f2 site also occurs at high melt dopings. Therefore, coercivity and saturation magnetization decreased.
http://dx.doi.org/10.1007/s10751-011-0361-1
Liquid-crystalline elastomer microvalve for microfluidics. - In: Advanced materials, ISSN 1521-4095, Bd. 23 (2011), 39, S. 4526-4530
http://dx.doi.org/10.1002/adma.201102277
The role of nanopore geometry for the rectification of ionic currents. - In: The journal of physical chemistry. Energy, materials, and catalysis / American Chemical Society. - Washington, DC : Soc., 2007- , ISSN: 1932-7455 , ZDB-ID: 2256522-X, ISSN 1932-7455, Bd. 115 (2011), 16, S. 7866-7873
http://dx.doi.org/10.1021/jp111377h
Pyrolyzed photoresist film electrodes for application in electroanalysis. - In: Journal of electrical engineering, ISSN 1339-309X, Bd. 62 (2011), 1, S. 49-53
https://doi.org/10.2478/v10187-011-0008-0
Einfache Modelle zur Beschreibung des atmosphärischen DC-Plasmaspritzprozesses. - In: Galvanotechnik, ISSN 0016-4232, Bd. 102 (2011), 7, S. 1612-1621
Studie der Kristallisationsbedingungen von Ti-dotierten, mit der Glaskristallisationstechnik hergestellten Bariumhexaferritpulvern für Mikrowellenanwendungen :
A crystallization conditions study of the Ti-doped barium hexaferrite powders synthesized with the glass crystallization technique for microwave applications. - In: Materials science and engineering technology, ISSN 1521-4052, Bd. 42 (2011), 8, S. 731-736
For microwave applications Titanium doped M-type hexagonal ferrites have been synthesized by means of Glass Crystallization Technique varying the crystallization parameters and the melt doping concentrations. The chosen melt dopings were x = 5.4 and 7.2 mole-% TiO2 with the following basic composition (mole-%): 40 BaO + 33 B2O3 + (27-x) Fe2O3 + x TiO2. We have studied the dependencies between the magnetic properties, the valence of the iron ions in the glasses and the powders, the formation of new dielectric phases and the microwave absorption. - After the Ti4+ ions substitutions, the magnetocrystalline anisotropy changed, this effect was observed in the static magnetic properties (JHC and MS) measured using a Vibration Sample Magnetometer. Furthermore the Ti4+ ions preferably occupy mainly the 2a as well as slightly the 2b sites in the lattice of the barium hexaferrite, which are studied using Mössbauer spectroscopy. Besides, the X-ray diffraction studies proved that the formation of the ferrimagnetic (BaFe12-xTixO12) and dielectric (BaTi6O13) phases are dependent on the crystallization parameters. - The controlled influencing of lattice sites occupation and of the Fe2+ content in the ferrimagnetic phase as well as the controlled formation of the dielectric phase rate during the annealing are possibilities to optimize the microwave absorption of Ti-doped barium hexaferrite powders synthesized by Glass Crystallization Technique. - Keywords: barium hexaferrite, microwave absorber, Mössbauer spectroscopy, titanium substitution, X-ray diffraction
http://dx.doi.org/10.1002/mawe.201100716