TY - JOUR A1 - Förster, Arnold A1 - Novák, J. A1 - Morvic, M. T1 - Wet chemical separation of low-temperature GaAs layers from their GaAs substrates / J. Novák ; M. Morvic ; J. Betko ; A. Förster ... JF - Materials science and engineering / B, Solid state materials for advanced technology. 40 (1996), H. 1 Y1 - 1996 SN - 0921-5107 SP - 58 EP - 62 ER - TY - JOUR A1 - Hoskens, R. C. P. A1 - Tolstikhin, V.I. A1 - Förster, Arnold A1 - Roer, T.G. van de T1 - Vertically integrated transistor-laser structure, take 2 JF - WOCSDICE 2000, 24th Workshop on Compound Semiconductor Devices and Integrated Circuits held in Europe : May 29 - June 02, 2000, Aegean Sea, Greece. Y1 - 2000 SN - 0970311109 N1 - WOCSDICE ; (24, 2000) Workshop on Compound Semiconductor Devices and Integrated Circuits held in Europe ; (24 : ; 2000.05.29-06.02) PB - Univ. of Michigan CY - Ann Arbor, Mich. ER - TY - JOUR A1 - Vogt, C. A1 - Mottaghy, Darius A1 - Rath, V. A1 - Marquart, G. A1 - Dijkshoorn, L. A1 - Wolf, A. A1 - Clauser, C. T1 - Vertical variation in heat flow on the Kola Peninsula: palaeoclimate or fluid flow? JF - Geophysical Journal International N2 - Following earlier studies, we present forward and inverse simulations of heat and fluid transport of the upper crust using a local 3-D model of the Kola area. We provide best estimates for palaeotemperatures and permeabilities, their errors and their dependencies. Our results allow discriminating between the two mentioned processes to a certain extent, partly resolving the non-uniqueness of the problem. We find clear indications for a significant contribution of advective heat transport, which, in turn, imply only slightly lower ground surface temperatures during the last glacial maximum relative to the present value. These findings are consistent with the general background knowledge of (i) the fracture zones and the corresponding fluid movements in the bedrock and (ii) the glacial history of the Kola area. Y1 - 2014 U6 - http://dx.doi.org/10.1093/gji/ggu282 SN - 1365-246X VL - 199 IS - 2 SP - 829 EP - 843 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Förster, Arnold A1 - Malzer, S. A1 - Heber, J. A1 - Peter, M. T1 - Vertical transport and relaxation mechanisms in d-doping superlattices. Malzer, S.; Heber, J.; Peter, M.; Eckl, S.; Elpelt, R.; Doehler, G. H.; Förster, A.; Lüth, H. JF - Physica E: Low-dimensional Systems and Nanostructures. 2 (1998), H. 1-4 Y1 - 1998 SN - 1386-9477 SP - 349 EP - 352 ER - TY - JOUR A1 - Helsper, Christoph A1 - Fißan, H. J. A1 - Muggli, J. A1 - Scheidweiler, A. T1 - Verification of Ionization Chamber Theory JF - Fire Technology. 19 (1983), H. 1 Y1 - 1983 SN - 1572-8099 SP - 14 EP - 21 ER - TY - JOUR A1 - Pieper, Martin T1 - Vector hyperinterpolation on the sphere JF - Journal of approximation theory. 156 (2009), H. 2 Y1 - 2009 SN - 0021-9045 SP - 173 EP - 186 ER - TY - JOUR A1 - Giresini, Linda A1 - Sassu, Mauro A1 - Butenweg, Christoph A1 - Alecci, Valerio A1 - De Stefano, Mario T1 - Vault macro-element with equivalent trusses in global seismic analyses JF - Earthquakes and Structures N2 - This paper proposes a quick and simplified method to describe masonry vaults in global seismic analyses of buildings. An equivalent macro-element constituted by a set of six trusses, two for each transverse, longitudinal and diagonal direction, is introduced. The equivalent trusses, whose stiffness is calculated by fully modeled vaults of different geometry, mechanical properties and boundary conditions, simulate the vault in both global analysis and local analysis, such as kinematic or rocking approaches. A parametric study was carried out to investigate the influence of geometrical characteristics and mechanical features on the equivalent stiffness values. The method was numerically validated by performing modal and transient analysis on a three naves-church in the elastic range. Vibration modes and displacement time-histories were compared showing satisfying agreement between the complete and the simplified models. This procedure is particularly useful in engineering practice because it allows to assess, in a simplified way, the effectiveness of strengthening interventions for reducing horizontal relative displacements between vault supports. KW - vault KW - macro-element KW - equivalent stiffness KW - truss KW - churches Y1 - 2017 U6 - http://dx.doi.org/10.12989/eas.2017.12.4.409 SN - 2092-7614 (Print) SN - 2092-7622 (Online) VL - 12 IS - 4 SP - 409 EP - 423 PB - Techno-Press CY - Taejŏn ER - TY - JOUR A1 - Jablonowski, Nicolai David A1 - Kollmann, Tobias A1 - Nabel, Moritz A1 - Damm, Tatjana A1 - Klose, Holger A1 - Müller, Michael A1 - Bläsing, Marc A1 - Seebold, Sören A1 - Krafft, Simone A1 - Kuperjans, Isabel A1 - Dahmen, Markus A1 - Schurr, Ulrich T1 - Valorization of Sida (Sida hermaphrodita) biomass for multiple energy purposes JF - GCB [Global Change Biology] Bioenergy N2 - The performance and biomass yield of the perennial energy plant Sida hermaphrodita (hereafter referred to as Sida) as a feedstock for biogas and solid fuel was evaluated throughout one entire growing period at agricultural field conditions. A Sida plant development code was established to allow comparison of the plant growth stages and biomass composition. Four scenarios were evaluated to determine the use of Sida biomass with regard to plant development and harvest time: (i) one harvest for solid fuel only; (ii) one harvest for biogas production only; (iii) one harvest for biogas production, followed by a harvest of the regrown biomass for solid fuel; and (iv) two consecutive harvests for biogas production. To determine Sida's value as a feedstock for combustion, we assessed the caloric value, the ash quality, and melting point with regard to DIN EN ISO norms. The results showed highest total dry biomass yields of max. 25 t ha⁻¹, whereas the highest dry matter of 70% to 80% was obtained at the end of the growing period. Scenario (i) clearly indicated the highest energy recovery, accounting for 439 288 MJ ha⁻¹; the energy recovery of the four scenarios from highest to lowest followed this order: (i) ≫ (iii) ≫ (iv) > (ii). Analysis of the Sida ashes showed a high melting point of >1500 °C, associated with a net calorific value of 16.5–17.2 MJ kg⁻¹. All prerequisites for DIN EN ISO norms were achieved, indicating Sida's advantage as a solid energy carrier without any post-treatment after harvesting. Cell wall analysis of the stems showed a constant lignin content after sampling week 16 (July), whereas cellulose had already reached a plateau in sampling week 4 (April). The results highlight Sida as a promising woody, perennial plant, providing biomass for flexible and multipurpose energy applications. Y1 - 2016 U6 - http://dx.doi.org/10.1111/gcbb.12346 SN - 1757-1707 (online) SN - 1757-1693 (print) N1 - Special Issue: Perennial biomass crops for a resource constrained world VL - 9 IS - 1 SP - 202 EP - 214 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Förster, Arnold T1 - Ultrahigh frequency measurements of magnetic penetration length and surface impedance of YBa2Cu3O7–x microstriplines on Si and GaAs substrates . Rüders, F; Hollricher, O.; Copetti, C. A. ; Förster, A. ; Buchal, Ch. ; Prusseit, W. ; Kinder, H. JF - Journal of Applied Physics. 77 (1995), H. 10 Y1 - 1995 SN - 1089-7550 SP - 5282 EP - 5286 ER - TY - JOUR A1 - Förster, Arnold A1 - Marso, M. A1 - Mikulics, V. V. A1 - Adam, R. T1 - Ultrafast Phenomena in Freestanding LT-GaAs Devices. Marso, M.; Mikulics, V. V.; Adam, R.; Wu, S.; Zheng, X.; Camara, I.; Siebe, N. Y.; Förster, A.; Güsten, R.; Kordos, P.; Sobolewski, R. JF - Acta physica Polonica / A. 107 (2005), H. 1 Y1 - 2005 SN - 0587-4246 SP - 109 EP - 117 ER -