TY - CONF A1 - Haase, Oskar T1 - High energy tomography and crack recognition T2 - Computerized tomography for industrial applications and image processingin Radiology CY - Berlin, Germany DA - 1999-03-15 PY - 1999 AN - OPUS4-18682 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Görner, Wolf A1 - Haase, Oskar A1 - Ostermann, Markus A1 - Segebade, Christian T1 - Instrumental analysis of phosphorus in organic material using high energy beta-counting after photoactivation (IPAA) N2 - C, N, O, F and P can be analyzed by instrumental photon activation analysis (IPAA) including decay curve analysis. The interference of 30P (T1/2 = 149.9 s) by 15O (T1/2 = 122.2 s) can be ruled out by direct positron measurement making use of the largely different maximum β+-energies of both nuclides (3.24 MeV and 1.73 MeV, respectively). Interference by carbon (11C) can be avoided by sub-threshold activation with 17 MeV bremsstrahlung. The short half-life of 30P allows a high productivity of the method. Reliability was demonstrated in the range of 0.2%–2% P (detection limit = 40 µg/g). Analysis of a certified reference material (BCR-CRM 063) yielded excellent agreement with the certified data. KW - Instrumental analysis KW - Phosphorus KW - Photon activation PY - 2008 DO - https://doi.org/10.1007/s10967-007-0441-5 SN - 0236-5731 SN - 1588-2780 SN - 1417-2097 VL - 276 IS - 1 SP - 251 EP - 255 PB - Elsevier Sequoia CY - Lausanne AN - OPUS4-19157 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Görner, Wolf A1 - Alber, D. A1 - Berger, Achim A1 - Haase, Oskar A1 - Monse, G. A1 - Segebade, Christian T1 - BEAMGAA - A chance for high precision analysis of big samples N2 - In activation analysis of traces in small samples, the non-equivalence of the activating radiation doses of sample and calibration material gives rise to sometimes tolerable systematic errors. Conversely, analysis of major components usually demands high trueness and precision. To meet this, beam geometry activation analysis (BEAMGAA) procedures have been developed for instrumental photon (IPAA) and neutron activation analysis (INAA) in which the activating neutron/photon beam exhibits broad, flat-topped characteristics. This results in a very low lateral activating flux gradient compared to known radiation facilities, however, at significantly lower flux density. The axial flux gradient can be accounted for by a monitor-sample-monitor assembly. As a first approach, major components were determined in high purity substances as well as selenium in a cattle fodder additive. T2 - 6th International Conference "Methods and Applications of Radioanalytical Chemistry" CY - Kailua-Kona, HI, United States of America DA - 2003-04-07 KW - Beam geometry activation analysis KW - Flux gradients KW - Measurement regime KW - Representativity KW - Big samples PY - 2005 DO - https://doi.org/10.1007/s10967-005-0660-6 SN - 0236-5731 SN - 1588-2780 SN - 1417-2097 VL - 263 IS - 3 SP - 791 EP - 796 PB - Elsevier Sequoia CY - Lausanne AN - OPUS4-6907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Görner, Wolf A1 - Berger, Achim A1 - Ecker, Klaus A1 - Haase, Oskar A1 - Hedrich, Martina A1 - Segebade, Christian A1 - Weidemann, Gerd A1 - Dudek, Gabriele T1 - Broad band application of combined instrumental photon and neutron activation analysis PY - 2001 SN - 0236-5731 SN - 1588-2780 SN - 1417-2097 N1 - Geburtsname von Dudek, Gabriele: Wermann, G. - Birth name of Dudek, Gabriele: Wermann, G. VL - 248 IS - 1 SP - 45 EP - 52 PB - Elsevier Sequoia CY - Lausanne AN - OPUS4-11229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Lehmann, Christian A1 - Haase, Oskar A1 - Rübner, Katrin A1 - Kühne, Hans-Carsten ED - Uzoegbo, H.C. ED - Schmidt, Wolfram T1 - Strength development and characterization of the reaction products of a one-part-geopolymer derived from a silica residue and sodium aluminate N2 - A silica-rich residue from waste-water treatment of chlorosilane production was tested for its applicability for the production of one-part geopolymers. The residue was blended with solid sodium aluminate, the blend activated with water and cured at 70 °C. The degree of reaction and strength were determined after 1,3, and 7 days. The reaction products were analyzed by means of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen Sorption, and small-angle X-ray Scattering (SAXS). Until the third day of curing the degree of reaction of the residue reached 51% and the strength reached 8.9 MPa. The reaction product was identified as geopolymer containing zeolite A. The results thus confirmed that the residue may be used in the production of geopolymers. However, from 3 to 7 days of curing no further progress of reaction was observed and the strength slightly decreased. It was observed that even harsh vacuum drying left some water, presumably zeolitic water and surface hydroxyl groups, in the hardened geopolymer, the volume fraction of the emptied pores was approximately 45%. The SEM and SAXS analyses showed the gel-like microstructure of the geopolymer with diameters of the gel particles of about 70 nm on average. In line with this colloidal particle size, the specific surface area of the geopolymer was measured by SAXS to be approximately 120 m2/g. On the contrary, nitrogen Sorption measurements yielded a specific surface area of only 13 mz/g and did not show the presence of micropores, which is attributable to the inaccessibility of the pores of the geopolymer and the zeolites for nitrogen at the measurement temperature. T2 - ACCTA - International conference on advances in cement and concrete technology in Africa 2013 CY - Johannesburg, South Africa DA - 28.01.2013 KW - Geopolymers KW - Waste materials KW - Sodium aluminate KW - Strength KW - Microstructure PY - 2013 SN - 978-3-9815360-3-4 SP - 253 EP - 259 AN - OPUS4-27758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hedrich, Martina A1 - Giese, Lutz A1 - Adam, Christian A1 - Haase, Oskar A1 - Segebade, Christian T1 - Recycling of Photovoltaic CdTe-Modules - Analytical Process Monitoring N2 - Along with the globally increasing energy demand the application of renewable energy sources is urgently required. According to national regulations and international treaties (e.g. Kyoto Protocol) these sources shall be sustainably available at reasonable financial effort and non-polluting during production, use and waste treatment. Using photovoltaic sources (PV), these requirements can clearly be met. All industry has to follow the best available technology and an integrative life cycle approach for their products and production. PV thin film technology strictly responds to this obligation. In order to save material resources and to minimise undesirable landfill recycling of spent PV modules is necessary. Recycling of multi-component materials containing mixed metals typically consists of three parts: liberation, separation, and recovery. In our study (RESOLVED – an EU Demonstration Project) the focus is on liberation and separation. The converting layer (CdTe) was liberated (removed) from the glass carrier by sandblasting and separated subsequently from the blast material (e.g. corundum) and other components using stepwise different separation techniques. Both the glass substrate and CdTe are subject to re-use. The overall feasibility of the recycling process is primarily governed by the efficiency of the procedure applied to the separation of CdTe from the rest (blasting material, glass residues, etc.). This was performed by water-based flotation. Several flotation procedures were studied regarding their separation yields. The distribution of CdTe in the phases involved (flotate, water, residue) was measured using energy dispersive X-ray fluorescence spectrometry (EDXRS) intended for future routine application and by instrumental large-volume photon activation analysis (IPAA) as a reference procedure. The results of both analytical methods were in satisfactory agreement. T2 - European Metallurgical Conference (EMC 2005) CY - Dresden, Germany DA - 2005-09-18 KW - Photovoltaic (PV) KW - Solar energy KW - CdTe-Modules KW - Recycling KW - Separation techniques KW - Monitoring PY - 2005 SN - 3-935797-22-2 VL - 4 SP - 1687 EP - 1696 PB - GDMB-Medienverl. CY - Clausthal-Zellerfeld AN - OPUS4-11004 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meyer-Plath, Asmus A1 - Orts Gil, Guillermo A1 - Petrov, Sergej A1 - Oleszak, Franz A1 - Maneck, Heinz-Eberhard A1 - Dörfel, Ilona A1 - Haase, Oskar A1 - Richter, Silke A1 - Mach, Reinhard T1 - Plasma-thermal purification and annealing of carbon nanotubes N2 - We have developed a very fast and entirely gas-phase based purification technique for carbon nanotubes (CNT) that allows removing metal and metal oxide impurities with high effectiveness. CNT agglomerates from chemical vapor deposition (CVD) synthesis which contained carbon encapsulated catalysts were injected into an atmospheric plasma torch. Very high heating rates allow for quasi-instantaneous vaporization of catalyst particles. This way, metal vapors are hyposized to break mechanically instable encapsulations and effuse from incomplete ones faster than thermally induced graphitization stabilizes such particle encapsulations. The ash content of multi-walled (MW) CNT samples was reduced to less than 15% of the initial value within a few milliseconds. Also the metal content of single-walled (SW) CNT agglomerates was significantly reduced. Repeated injection of CNT agglomerates into the plasma torch resulted in higher-purity products of improved structural integrity and increased oxidation resistance. PY - 2012 DO - https://doi.org/10.1016/j.carbon.2012.04.049 SN - 0008-6223 SN - 1873-3891 VL - 50 IS - 10 SP - 3934 EP - 3942 PB - Pergamon Press CY - New York, NY AN - OPUS4-25986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Lehmann, Christian A1 - Haase, Oskar A1 - Rübner, Katrin A1 - Kühne, Hans-Carsten T1 - Geopolymerisation kieselsäurehaltiger Filterrückstände aus der Reststoffaufbereitung der Chlorsilanproduktion T2 - 18. Ibausil - Internationale Baustofftagung CY - Weimar, Germany DA - 2012-09-12 KW - Geopolymere KW - Reststoffe PY - 2012 SN - 978-3-00-034075-8 VL - 1 IS - 3.07 SP - 1-0517 - 1-0524 AN - OPUS4-26544 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -