@article{RiglingEilmannKoechlietal.2010, author = {Rigling, Andreas and Eilmann, Britta and Koechli, Roger and Dobbertin, Matthias}, title = {Mistletoe-induced crown degradation in Scots pine in a xeric environment}, volume = {30}, number = {7}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1758-4469 (Online)}, doi = {10.1093/treephys/tpq038}, pages = {845 -- 832}, year = {2010}, abstract = {Increasing Scots pine (Pinus sylvestris L.) mortality has been recently observed in the dry inner valleys of the European Alps. Besides drought, infection with pine mistletoe (Viscum album ssp. austriacum) seems to play an important role in the mortality dynamics of Scots pines, but how mistletoes promote pine decline remains unclear. To verify whether pine mistletoe infection weakens the host via crown degradation, as observed for dwarf mistletoes, we studied the negative effects of pine mistletoe infestation on the photosynthetic tissues and branch growth of pairs of infested and non-infested branches. Pine mistletoe infection leads to crown degradation in its host by reducing the length, the radial increment, the ramification, the needle length and the number of needle years of the infested branches. This massive loss in photosynthetic tissue results in a reduction in primary production and a subsequent decrease in carbohydrate availability. The significant reduction in needle length due to mistletoe infection is an indication for a lower water and nutrient availability in infested branches. Thus, mistletoe infection might lead to a decrease in the availability of water and carbohydrates, the two most important growth factors, which are already shortened due to the chronic drought situation in the area. Therefore, pine mistletoe increases the risk of drought-induced mortality of its host when growing in a xeric environment.}, language = {en} } @article{BragardSoltauThomasetal.2010, author = {Bragard, Michael and Soltau, N. and Thomas, S. and De Doncker, R. W.}, title = {The balance of renewable sources and user demands in grids : power electronics for modular battery energy storage systems}, series = {IEEE transactions on power electronics}, volume = {25}, journal = {IEEE transactions on power electronics}, number = {12}, publisher = {IEEE}, address = {New York}, issn = {0885-8993}, doi = {10.1109/TPEL.2010.2085455}, pages = {3049 -- 3056}, year = {2010}, abstract = {The continuously growing amount of renewable sources starts compromising the stability of electrical grids. Contradictory to fossil fuel power plants, energy production of wind and photovoltaic (PV) energy is fluctuating. Although predictions have significantly improved, an outage of multi-MW offshore wind farms poses a challenging problem. One solution could be the integration of storage systems in the grid. After a short overview, this paper focuses on two exemplary battery storage systems, including the required power electronics. The grid integration, as well as the optimal usage of volatile energy reserves, is presented for a 5- kW PV system for home application, as well as for a 100- MW medium-voltage system, intended for wind farm usage. The efficiency and cost of topologies are investigated as a key parameter for large-scale integration of renewable power at medium- and low-voltage.}, language = {en} } @article{BenzelLinzbach2010, author = {Benzel, Ute and Linzbach, Meike}, title = {Bilanzierung und Offenlegung von Ertragsteuerrisiken - Quo vadis? Unsichere Steuerpositionen in der Rechnungslegung nach IFRS, US-GAAP und HGB}, series = {IRZ - Zeitschrift f{\"u}r Internationale Rechnungslegung}, journal = {IRZ - Zeitschrift f{\"u}r Internationale Rechnungslegung}, number = {11}, issn = {1862-5533}, pages = {475 -- 523}, year = {2010}, abstract = {In den letzten drei bis vier Jahren unterlag der Bereich der Bilanzierung und Offenlegung von unsicheren Steuerpositionen im IFRS- und US-GAAP-Abschluss einem stetigen Wandel. Sowohl nach US-GAAP als auch nach IFRS nehmen die Anforderungen an die Bilanzierung und Offenlegung best{\"a}ndig zu. Schon allein dies zeigt die Bedeutung, die dem Themenbereich der Steuerrisiken beigemessen wird. Aber nicht nur im Rahmen der Berichterstattung im Jahresabschluss stehen Steuerrisiken oben auf der Agenda, auch der amerikanische Internal Revenue Service (IRS) verfolgt das Thema sehr konsequent und plant, bestimmte Unternehmen zu Angaben von Steuerrisiken im Rahmen der Steuererkl{\"a}rungen zu verpflichten. Der Aufsatz befasst sich mit den neueren Entwicklungen im Bereich der Bilanzierung und Offenlegung von unsicheren Steuerpositionen in der Rechnungslegung nach IFRS, US-GAAP und HGB und der Offenlegung von Steuerrisiken im Rahmen der Steuererkl{\"a}rung.}, language = {de} } @article{WollertLeidinger2010, author = {Wollert, J{\"o}rg and Leidinger, Rafael}, title = {Automation trifft Automotive : SPS in der Fahrzeugtechnik}, series = {Elektronik automotive : Magazin f{\"u}r Entwicklungen in der Kfz-Elektronik und Telematik}, journal = {Elektronik automotive : Magazin f{\"u}r Entwicklungen in der Kfz-Elektronik und Telematik}, number = {4/5}, publisher = {WEKA Fachmedien}, address = {Haar}, issn = {1614-0125}, pages = {44 -- 48}, year = {2010}, abstract = {Eine SPS im Kraftfahrzeug? Das geht ja gar nicht - da gibt es doch all die Hersteller f{\"u}r Kfz-Steuerger{\"a}te, die konfigurierbare Hardware anbieten. Im Prinzip ja, aber leider sind gerade die Sensoren oder Aktoren nicht ansteuerbar, die der Entwickler genau f{\"u}r sein aktuelles Projekt ben{\"o}tigt. Dieser Beitrag gibt einen kleinen Einblick in neue M{\"o}glichkeiten des Rapid Prototyping f{\"u}r mechatronische Systeme auf der Basis von Speicherprogrammierbaren Steuerungen (SPS).}, language = {de} } @article{DegeringEggertPulsetal.2010, author = {Degering, Christian and Eggert, Thorsten and Puls, Michael and Bongaerts, Johannes and Evers, Stefan and Maurer, Karl-Heinz and Jaeger, Karl-Erich}, title = {Optimization of protease secretion in Bacillus subtilis and Bacillus licheniformis by screening of homologous and herologous signal peptides}, series = {Applied and environmental microbiology}, volume = {76}, journal = {Applied and environmental microbiology}, number = {19}, publisher = {American Society for Microbiology}, address = {Washington, DC}, issn = {1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)}, doi = {10.1128/AEM.01146-10}, pages = {6370 -- 6378}, year = {2010}, abstract = {Bacillus subtilis and Bacillus licheniformis are widely used for the large-scale industrial production of proteins. These strains can efficiently secrete proteins into the culture medium using the general secretion (Sec) pathway. A characteristic feature of all secreted proteins is their N-terminal signal peptides, which are recognized by the secretion machinery. Here, we have studied the production of an industrially important secreted protease, namely, subtilisin BPN′ from Bacillus amyloliquefaciens. One hundred seventy-three signal peptides originating from B. subtilis and 220 signal peptides from the B. licheniformis type strain were fused to this secretion target and expressed in B. subtilis, and the resulting library was analyzed by high-throughput screening for extracellular proteolytic activity. We have identified a number of signal peptides originating from both organisms which produced significantly increased yield of the secreted protease. Interestingly, we observed that levels of extracellular protease were improved not only in B. subtilis, which was used as the screening host, but also in two different B. licheniformis strains. To date, it is impossible to predict which signal peptide will result in better secretion and thus an improved yield of a given extracellular target protein. Our data show that screening a library consisting of homologous and heterologous signal peptides fused to a target protein can identify more-effective signal peptides, resulting in improved protein export not only in the original screening host but also in different production strains.}, language = {en} } @article{ReisgenSchleserMokrovetal.2010, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Uni- and bi-axial deformation behavior of laser welded advanced high strength steel sheets}, series = {Journal of materials processing technology}, volume = {210}, journal = {Journal of materials processing technology}, number = {15}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0924-0136}, doi = {http10.1016/j.jmatprotec.2010.08.003}, pages = {2188 -- 2196}, year = {2010}, abstract = {Bead-on-plate butt joints of 2.5 mm hot rolled DP600/DP600 and 1.2 mm cold rolled TRIP700/TRIP700 steel sheets were performed using 6 kW CO2 laser beam welding. The welding speed ranged from 1.5 to 3.0 and from 2.1 to 3.9 m/min in DP/DP and TRIP/TRIP steel weldments respectively. A top surface helium gas was used as a shielding gas at a flow rate of 20 l/min. Metallographic examinations and transverse tensile testing (DIN EN 895: 1995) were carried out to characterize the weldments. The formability of base metals and weldments were investigated by standard Erichsen test (DIN EN ISO 20482). It was found that the uniaxial plastic behavior of both DP600 and TRIP700 base metals was in agreement with Swift and modified Mecking-Kocks models respectively. In a perpendicular tensile test to the weld line, all specimens were fractured at the base metal however the strengths were somewhat higher than those of base metal. There was a significant reduction in formability caused by welding of both DP/DP and TRIP/TRIP steel weldments and the formability has been improved with the increase of the welding speed.}, language = {en} } @article{ReisgenSchleserJerabeketal.2010, author = {Reisgen, Uwe and Schleser, Markus and Jerabek, Jakub and Chudoba, Rostislav}, title = {Messung der Strahlqualit{\"a}t einer Elektronenstrahlanlage in Umgebungsatmosph{\"a}re}, series = {Materialwissenschaft und Werkstofftechnik}, volume = {41}, journal = {Materialwissenschaft und Werkstofftechnik}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4052}, pages = {45 -- 52}, year = {2010}, abstract = {In den letzten Jahrzehnten hat das Elektronenstrahlschweißen, das bereits im gr{\"o}ßeren Maßstab verwendet wird, seine F{\"a}higkeit als qualitatives Werkzeug f{\"u}r die Verbindung verschiedener Materialen nachgewiesen. Das Non Vacuum Electron Beam Welding (NV-EBW) hat zahlreiche Vorteile im Vergleich zum Elektronenstrahlschweißen im Vakuum, da man unter normalem Atmosph{\"a}rendruck arbeiten kann. Im Hinblick auf die reproduzierbare Qualit{\"a}t, insbesondere im Bereich der Massen-Fertigung, ist die Kontrolle der Strahlparameter sowie deren Einfluss auf das Schweißergebnis von großer Bedeutung. Durch eine genaue Kenntnis der Strahlkenngr{\"o}ßen wie des Strahldurchmessers und der Leistungsdichteverteilung kann eine Aussage {\"u}ber die sich ausbildende Schweißnaht sowie die Schweißbaddynamik getroffen werden. Messungen der Strahlkenngr{\"o}ßen im Prozess erlauben insbesondere die Untersuchung von Humping-Effekten. In diesem Beitrag wird der Prozess der Elektronenstrahlvermessung unter atmosph{\"a}rischen Bedingungen beschrieben. Es wird zudem die Abh{\"a}ngigkeit der Elektronenstrahlcharakteristika von den verschiedenen Prozessparametern dargestellt.}, language = {de} } @article{KuhnhenneDoeringFeldmann2010, author = {Kuhnhenne, Markus and D{\"o}ring, Bernd and Feldmann, Markus}, title = {Grunds{\"a}tze und L{\"o}sungen zur W{\"a}rmebr{\"u}ckenreduktion im Metallleichtbau}, series = {Stahlbau}, volume = {79}, journal = {Stahlbau}, number = {5}, publisher = {Ernst \& Sohn}, address = {Berlin}, issn = {1437-1049 (E-Journal); 0038-9145 (Print)}, doi = {10.1002/stab.201001330}, pages = {345 -- 355}, year = {2010}, abstract = {Die Anforderungen an das energiesparende Bauen sind mit der Einf{\"u}hrung der Energieeinsparverordnung (EnEV) 2009 auch im Industrie- und Gewerbebau deutlich versch{\"a}rft worden. Einen wesentlichen Beitrag zur Energieeinsparung liefert die Minimierung des Transmissionsw{\"a}rmetransfers. Analysiert man Geb{\"a}udeh{\"u}llen in Metallleichtbauweise stellt man fest, dass eine Erh{\"o}hung der W{\"a}rmed{\"a}mmst{\"a}rke allein noch nicht zielf{\"u}hrend ist, zus{\"a}tzlich sind W{\"a}rmebr{\"u}ckeneffekte zu ber{\"u}cksichtigen und deren Einfl{\"u}sse auf die W{\"a}rmetransmission zu reduzieren. Neben der Bedeutung f{\"u}r die Energieeinsparung ist eine w{\"a}rmetechnisch optimierte Detailausbildung auch erforderlich, um einen ausreichenden Feuchteschutz (Vermeidung von Tauwasser und Schimmelpilz) zu realisieren und so Sch{\"a}den zu vermeiden. Ein wichtiges Hilfsmittel stellt hierzu der vom Industrieverband f{\"u}r Bausysteme im Metallleichtbau (IFBS) herausgegebene W{\"a}rmebr{\"u}ckenatlas der Metall-Sandwichbauweise dar.}, language = {de} } @article{MukherjeePrahlBlecketal.2010, author = {Mukherjee, Krishnendu and Prahl, Ulrich and Bleck, Wolfgang and Reisgen, Uwe and Schleser, Markus and Abdurakhmanov, Aydemir}, title = {Characterization and modelling techniques for gas metal arc welding of DP 600 sheet steels}, series = {Materialwissenschaft und Werkstofftechnik}, volume = {41}, journal = {Materialwissenschaft und Werkstofftechnik}, number = {11}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4052}, doi = {10.1002/mawe.201000692}, pages = {972 -- 983}, year = {2010}, abstract = {The objectives of the present work are to characterize the Gas Metal Arc Welding process of DP 600 sheet steel and to summarize the modelling techniques. The time-temperature evolution during the welding cycle was measured experimentally and modelled with the softwaretool SimWeld. To model the phase transformations during the welding cycle dilatometer tests were done to quantify the parameters for phase field modelling by MICRESS®. The important input parameters are interface mobility, nucleation density, etc. A contribution was made to include austenite to bainite transformation in MICRESS®. This is useful to predict the microstructure in the fast cooling segments. The phase transformation model is capable to predict the microstructure along the heating and cooling cycles of welding. Tensile tests have shown the evidence of failure at the heat affected zone, which has the ferrite-tempered martensite microstructure.}, language = {en} } @article{ReisgenSchleserMokrovetal.2010, author = {Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg and Ahmed, Essam}, title = {Shielding gas influences on laser weldability of tailored blanks of advanced automotive steels}, series = {Applied surface science}, volume = {257}, journal = {Applied surface science}, number = {5}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0169-4332 (E-Journal); 0169-4332 (Print)}, doi = {10.1016/j.apsusc.2010.08.042}, pages = {1401 -- 1406}, year = {2010}, abstract = {The effects of shielding gas types and flow rates on CO2 laser weldability of DP600/TRIP700 steel sheets were studied in this work. The evaluated shielding gases were helium (He), argon (Ar) and different mixtures of He and Ar. Weld penetration, tensile strength and formability (Erichsen test) of laser welds were found to be strongly dependent upon the shielding gas types. The ability of shielding gas in removing plasma plume and thus increasing weld penetration is believed to be closely related to ionization potential and atomic weight which determine the period of plasma formation and disappearance. It was found that the higher helium shielding gas flow rate, the deeper weld penetration and the lower weld width.}, language = {en} }