TY  - JOUR
A1  - Rübbelke, Dirk
A1  - Vögele, Stefan
A1  - Grajewski, Matthias
A1  - Zobel, Luzy
T1  - Hydrogen-based steel production and global climate protection: An empirical analysis of the potential role of a European cross border adjustment mechanism
JF  - Journal of Cleaner Production
N2  - The European Union's aim to become climate neutral by 2050 necessitates ambitious efforts to reduce carbon emissions. Large reductions can be attained particularly in energy intensive sectors like iron and steel. In order to prevent the relocation of such industries outside the EU in the course of tightening environmental regulations, the establishment of a climate club jointly with other large emitters and alternatively the unilateral implementation of an international cross-border carbon tax mechanism are proposed. This article focuses on the latter option choosing the steel sector as an example. In particular, we investigate the financial conditions under which a European cross border mechanism is capable to protect hydrogen-based steel production routes employed in Europe against more polluting competition from abroad. By using a floor price model, we assess the competitiveness of different steel production routes in selected countries. We evaluate the climate friendliness of steel production on the basis of specific GHG emissions. In addition, we utilize an input-output price model. It enables us to assess impacts of rising cost of steel production on commodities using steel as intermediates. Our results raise concerns that a cross-border tax mechanism will not suffice to bring about competitiveness of hydrogen-based steel production in Europe because the cost tends to remain higher than the cost of steel production in e.g. China. Steel is a classic example for a good used mainly as intermediate for other products. Therefore, a cross-border tax mechanism for steel will increase the price of products produced in the EU that require steel as an input. This can in turn adversely affect competitiveness of these sectors. Hence, the effects of higher steel costs on European exports should be borne in mind and could require the cross-border adjustment mechanism to also subsidize exports.
Y1  - 2022
U6  - https://doi.org/10.1016/j.jclepro.2022.135040
SN  - 0959-6526
VL  - 380
IS  - Part 2, Art. Nr.:135040
PB  - Elsevier
ER  - 
TY  - JOUR
A1  - Engel, Mareike
A1  - Bayer, Hendrik
A1  - Holtmann, Dirk
A1  - Tippkötter, Nils
A1  - Ulber, Roland
T1  - Flavin secretion of Clostridium acetobutylicum in a bioelectrochemical system - Is an iron limitation involved?
JF  - Bioelectrochemistry
Y1  - 2019
U6  - https://doi.org/10.1016/j.bioelechem.2019.05.014
SN  - 1567-5394
IS  - In Press, Accepted Manuscript
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Kronhardt, Valentina
A1  - Alexopoulos, Spiros
A1  - Reißel, Martin
A1  - Sattler, Johannes Christoph
A1  - Hoffschmidt, Bernhard
A1  - Hänel, Matthias
A1  - Doerbeck, Till
T1  - High-temperature thermal storage system for solar tower power plants with open-volumetric air receiver simulation and energy balancing of a discretized model
JF  - Energy procedia
N2  - This paper describes the modeling of a high-temperature storage system for an existing solar tower power plant with open volumetric receiver technology, which uses air as heat transfer medium (HTF). The storage system model has been developed in the simulation environment Matlab/Simulink®. The storage type under investigation is a packed bed thermal energy storage system which has the characteristics of a regenerator. Thermal energy can be stored and discharged as required via the HTF air. The air mass flow distribution is controlled by valves, and the mass flow by two blowers. The thermal storage operation strategy has a direct and significant impact on the energetic and economic efficiency of the solar tower power plants.
Y1  - 2014
U6  - https://doi.org/10.1016/j.egypro.2014.03.094
SN  - 1876-6102 (E-Journal) ; 1876-6102 (Print)
VL  - 49
SP  - 870
EP  - 877
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Oertel, Mario
A1  - Bung, Daniel Bernhard
T1  - Stability and scour development of bed material on crossbar block ramps
JF  - International journal of sediment research
N2  - Block ramps are ecologically oriented drop structures with adequate energy dissipation and partially moderate flow velocities. A special case is given with crossbar block ramps, where the upstream and downstream level difference is reduced by a series of basins. To prevent the total structure from failing, the stability of single boulders within the crossbars and the bed material in between must be guaranteed. The present paper addresses the stability of bed material and scour development for various flow regimes. Any bed material erosion may affect the stability of the crossbar boulders, which in turn can result in major damages of the ramp. Therefore new design approaches are developed to choose an appropriate bed material size and to avoid failures of crossbar block ramp structures.
Y1  - 2015
U6  - https://doi.org/10.1016/j.ijsrc.2014.12.003
SN  - 1001-6279
VL  - 30
IS  - 4
SP  - 344
EP  - 350
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schael, S.
A1  - Atanasyan, A.
A1  - Berdugo, J.
A1  - Bretz, T.
A1  - Czupalla, Markus
A1  - Dachwald, Bernd
A1  - Doetinchem, P. von
A1  - Duranti, M.
A1  - Gast, H.
A1  - Karpinski, W.
A1  - Kirn, T.
A1  - Lübelsmeyer, K.
A1  - Maña, C.
A1  - Marrocchesi, P.S.
A1  - Mertsch, P.
A1  - Moskalenko, I.V.
A1  - Schervan, T.
A1  - Schluse, M.
A1  - Schröder, K.-U.
A1  - Schultz von Dratzig, A.
A1  - Senatore, C.
A1  - Spies, L.
A1  - Wakely, S.P.
A1  - Wlochal, M.
A1  - Uglietti, D.
A1  - Zimmermann, J.
T1  - AMS-100: The next generation magnetic spectrometer in space – An international science platform for physics and astrophysics at Lagrange point 2
JF  - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Y1  - 2019
U6  - https://doi.org/10.1016/j.nima.2019.162561
SN  - 0168-9002
VL  - 944
IS  - 162561
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Grajewski, Matthias
A1  - Hron, Jaroslav
A1  - Turek, Stefan
T1  - Dual weighted a posteriori error estimation for a new nonconforming linear finite element on quadrilaterals
JF  - Applied Numerical Mathematics
N2  - After a short introduction of a new nonconforming linear finite element on quadrilaterals recently developed by Park, we derive a dual weighted residual-based a posteriori error estimator (in the sense of Becker and Rannacher) for this finite element. By computing a corresponding dual solution we estimate the error with respect to a given target error functional. The reliability and efficiency of this estimator is analyzed in several numerical experiments.
Y1  - 2005
U6  - https://doi.org/10.1016/j.apnum.2004.09.016
SN  - 0168-9274
VL  - 54
IS  - 3-4
SP  - 504
EP  - 518
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Defosse, Jerome
A1  - Kleinschmidt, Joris
A1  - Schmutz, Axel
A1  - Loop, Torsten
A1  - Staat, Manfred
A1  - Gatzweiler, Karl-Heinz
A1  - Wappler, Frank
A1  - Schieren, Mark
T1  - Dental strain on maxillary incisors during tracheal intubation with double-lumen tubes and different laryngoscopy techniques - a blinded manikin study
JF  - Journal of Cardiothoracic and Vascular Anesthesia
KW  - anaesthetic complications
KW  - dental trauma
KW  - difficult airway
KW  - double-lumen tube intubation
KW  - videolaryngoscopy
Y1  - 2022
U6  - https://doi.org/10.1053/j.jvca.2022.02.017
SN  - 1053-0770
VL  - 36
IS  - 8, Part B
SP  - 3021
EP  - 3027
PB  - Elsevier
CY  - New York, NY
ER  - 
TY  - JOUR
A1  - Kowalski, Julia
A1  - Linder, Peter
A1  - Zierke, S.
A1  - Wulfen, B. van
A1  - Clemens, J.
A1  - Konstantinidis, K.
A1  - Ameres, G.
A1  - Hoffmann, R.
A1  - Mikucki, J.
A1  - Tulaczyk, S.
A1  - Funke, O.
A1  - Blandfort, D.
A1  - Espe, Clemens
A1  - Feldmann, Marco
A1  - Francke, Gero
A1  - Hiecker, S.
A1  - Plescher, Engelbert
A1  - Schöngarth, Sarah
A1  - Dachwald, Bernd
A1  - Digel, Ilya
A1  - Artmann, Gerhard
A1  - Eliseev, D.
A1  - Heinen, D.
A1  - Scholz, F.
A1  - Wiebusch, C.
A1  - Macht, S.
A1  - Bestmann, U.
A1  - Reineking, T.
A1  - Zetzsche, C.
A1  - Schill, K.
A1  - Förstner, R.
A1  - Niedermeier, H.
A1  - Szumski, A.
A1  - Eissfeller, B.
A1  - Naumann, U.
A1  - Helbing, K.
T1  - Navigation technology for exploration of glacier ice with maneuverable melting probes
JF  - Cold Regions Science and Technology
N2  - The Saturnian moon Enceladus with its extensive water bodies underneath a thick ice sheet cover is a potential candidate for extraterrestrial life. Direct exploration of such extraterrestrial aquatic ecosystems requires advanced access and sampling technologies with a high level of autonomy. A new technological approach has been developed as part of the collaborative research project Enceladus Explorer (EnEx). The concept is based upon a minimally invasive melting probe called the IceMole. The force-regulated, heater-controlled IceMole is able to travel along a curved trajectory as well as upwards. Hence, it allows maneuvers which may be necessary for obstacle avoidance or target selection. Maneuverability, however, necessitates a sophisticated on-board navigation system capable of autonomous operations. The development of such a navigational system has been the focal part of the EnEx project. The original IceMole has been further developed to include relative positioning based on in-ice attitude determination, acoustic positioning, ultrasonic obstacle and target detection integrated through a high-level sensor fusion. This paper describes the EnEx technology and discusses implications for an actual extraterrestrial mission concept.
Y1  - 2016
U6  - https://doi.org/10.1016/j.coldregions.2015.11.006
SN  - 0165-232X
IS  - 123
SP  - 53
EP  - 70
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Valero, Daniel
A1  - Bung, Daniel Bernhard
T1  - Reformulating self-aeration in hydraulic structures: Turbulent growth of free surface perturbations leading to air entrainment
JF  - International Journal of Multiphase Flow
N2  - A new formulation for the prediction of free surface dynamics related to the turbulence occurring nearby is proposed. This formulation, altogether with a breakup criterion, can be used to compute the inception of self-aeration in high velocity flows like those occurring in hydraulic structures. Assuming a simple perturbation geometry, a kinematic and a non-linear momentum-based dynamic equation are formulated and forces acting on a control volume are approximated. Limiting steepness is proposed as an adequate breakup criterion. Role of the velocity fluctuations normal to the free surface is shown to be the main turbulence quantity related to self-aeration and the role of the scales contained in the turbulence spectrum are depicted. Surface tension force is integrated accounting for large displacements by using differential geometry for the curvature estimation. Gravity and pressure effects are also contemplated in the proposed formulation. The obtained equations can be numerically integrated for each wavelength, hence resulting in different growth rates and allowing computation of the free surface roughness wavelength distribution. Application to a prototype scale spillway (at the Aviemore dam) revealed that most unstable wavelength was close to the Taylor lengthscale. Amplitude distributions have been also obtained observing different scaling for perturbations stabilized by gravity or surface tension. The proposed theoretical framework represents a new conceptualization of self-aeration which explains the characteristic rough surface at the non-aerated region as well as other previous experimental observations which remained unresolved for several decades.
Y1  - 2018
U6  - https://doi.org/10.1016/j.ijmultiphaseflow.2017.12.011
SN  - 0301-9322
VL  - 100
SP  - 127
EP  - 142
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Kurulgan Demirci, Eylem
A1  - Demirci, Taylan
A1  - Linder, Peter
A1  - Trzewik, Jürgen
A1  - Gierkowski, Jessica Ricarda
A1  - Gossmann, Matthias
A1  - Kayser, Peter
A1  - Porst, Dariusz
A1  - Digel, Ilya
A1  - Artmann, Gerhard
A1  - Temiz Artmann, Aysegül
T1  - rhAPC reduces the endothelial cell permeability via a decrease of contractile tensions induced by endothelial cells
JF  - Journal of Bioscience and Bioengineering
N2  - All cells generate contractile tension. This strain is crucial for mechanically controlling the cell shape, function and survival. In this study, the CellDrum technology quantifying cell's (the cellular) mechanical tension on a pico-scale was used to investigate the effect of lipopolysaccharide (LPS) on human aortic endothelial cell (HAoEC) tension. The LPS effect during gram-negative sepsis on endothelial cells is cell contraction causing endothelium permeability increase. The aim was to finding out whether recombinant activated protein C (rhAPC) would reverse the endothelial cell response in an in-vitro sepsis model. In this study, the established in-vitro sepsis model was confirmed by interleukin 6 (IL-6) levels at the proteomic and genomic levels by ELISA, real time-PCR and reactive oxygen species (ROS) activation by florescence staining. The thrombin cellular contraction effect on endothelial cells was used as a positive control when the CellDrum technology was applied. Additionally, the Ras homolog gene family, member A (RhoA) mRNA expression level was checked by real time-PCR to support contractile tension results. According to contractile tension results, the mechanical predominance of actin stress fibers was a reason of the increased endothelial contractile tension leading to enhanced endothelium contractility and thus permeability enhancement. The originality of this data supports firstly the basic measurement principles of the CellDrum technology and secondly that rhAPC has a beneficial effect on sepsis influenced cellular tension. The technology presented here is promising for future high-throughput cellular tension analysis that will help identify pathological contractile tension responses of cells and prove further cell in-vitro models.
KW  - Cell permeability
KW  - Cellular force
KW  - Endothelial cells
KW  - Recombinant activated protein C
KW  - Lipopolysaccharide
KW  - Contractile tension
KW  - CellDrum
Y1  - 2012
U6  - https://doi.org/10.1016/j.jbiosc.2012.03.019
SN  - 1347-4421
VL  - 113
IS  - 2
SP  - 212
EP  - 219
PB  - Elsevier
CY  - Amsterdam
ER  -