TY  - JOUR
A1  - Moret, J.L.T.M.
A1  - Alkemade, J.
A1  - Upcraft, T.M.
A1  - Paulßen, Elisabeth
A1  - Wolterbeek, H.T.
A1  - Ommen, J.R. van
A1  - Denkova, A.G.
T1  - The application of atomic layer deposition in the production of sorbents for ⁹⁹Mo/⁹⁹ᵐTc generator
JF  - Applied Radiation and Isotopes
N2  - New production routes for ⁹⁹Mo are steadily gaining importance. However, the obtained specific activity is much lower than currently produced by the fission of U-235. To be able to supply hospitals with ⁹⁹Mo/⁹⁹ᵐTc generators with the desired activity, the adsorption capacity of the column material should be increased. In this paper we have investigated whether the gas phase coating technique Atomic Layer Deposition (ALD), which can deposit ultra-thin layers on high surface area materials, can be used to attain materials with high adsorption capacity for ⁹⁹Mo. For this purpose, ALD was applied on a silica-core sorbent material to coat it with a thin layer of alumina. This sorbent material shows to have a maximum adsorption capacity of 120 mg/g and has a ⁹⁹ᵐTc elution efficiency of 55 ± 2% based on 3 executive elutions.
Y1  - 2020
U6  - https://doi.org/10.1016/j.apradiso.2020.109266
SN  - 0969-8043
VL  - 164
IS  - 109266
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Muschallik, Lukas
A1  - Kipp, Carina Ronja
A1  - Recker, Inga
A1  - Bongaerts, Johannes
A1  - Pohl, Martina
A1  - Gelissen, Melanie
A1  - Schöning, Michael Josef
A1  - Selmer, Thorsten
A1  - Siegert, Petra
T1  - Synthesis of α-hydroxy ketones and vicinal diols with the Bacillus licheniformis DSM 13T butane-2, 3-diol dehydrogenase
JF  - Journal of Biotechnology
N2  - The enantioselective synthesis of α-hydroxy ketones and vicinal diols is an intriguing field because of the broad applicability of these molecules. Although, butandiol dehydrogenases are known to play a key role in the production of 2,3-butandiol, their potential as biocatalysts is still not well studied. Here, we investigate the biocatalytic properties of the meso-butanediol dehydrogenase from Bacillus licheniformis DSM 13T (BlBDH). The encoding gene was cloned with an N-terminal StrepII-tag and recombinantly overexpressed in E. coli. BlBDH is highly active towards several non-physiological diketones and α-hydroxyketones with varying aliphatic chain lengths or even containing phenyl moieties. By adjusting the reaction parameters in biotransformations the formation of either the α-hydroxyketone intermediate or the diol can be controlled.
Y1  - 2020
SN  - 2590-1559
U6  - https://doi.org/10.1016/j.jbiotec.2020.09.016
VL  - 202
IS  - Vol. 324
SP  - 61
EP  - 70
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Muschallik, Lukas
A1  - Molinnus, Denise
A1  - Jablonski, Melanie
A1  - Kipp, Carina Ronja
A1  - Bongaerts, Johannes
A1  - Pohl, Martina
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Selmer, Thorsten
A1  - Siegert, Petra
T1  - Synthesis of α-hydroxy ketones and vicinal (R, R)-diols by Bacillus clausii DSM 8716ᵀ butanediol dehydrogenase
JF  - RSC Advances
N2  - α-hydroxy ketones (HK) and 1,2-diols are important building blocks for fine chemical synthesis. Here, we describe the R-selective 2,3-butanediol dehydrogenase from B. clausii DSM 8716ᵀ (BcBDH) that belongs to the metal-dependent medium chain dehydrogenases/reductases family (MDR) and catalyzes the selective asymmetric reduction of prochiral 1,2-diketones to the corresponding HK and, in some cases, the reduction of the same to the corresponding 1,2-diols. Aliphatic diketones, like 2,3-pentanedione, 2,3-hexanedione, 5-methyl-2,3-hexanedione, 3,4-hexanedione and 2,3-heptanedione are well transformed. In addition, surprisingly alkyl phenyl dicarbonyls, like 2-hydroxy-1-phenylpropan-1-one and phenylglyoxal are accepted, whereas their derivatives with two phenyl groups are not substrates. Supplementation of Mn²⁺ (1 mM) increases BcBDH's activity in biotransformations. Furthermore, the biocatalytic reduction of 5-methyl-2,3-hexanedione to mainly 5-methyl-3-hydroxy-2-hexanone with only small amounts of 5-methyl-2-hydroxy-3-hexanone within an enzyme membrane reactor is demonstrated.
Y1  - 2020
U6  - https://doi.org/10.1039/D0RA02066D
SN  - 2046-2069
VL  - 10
SP  - 12206
EP  - 12216
PB  - Royal Society of Chemistry (RSC)
CY  - Cambridge
ER  - 
TY  - BOOK
A1  - Mühl, Thomas
T1  - Elektrische Messtechnik: Grundlagen, Messverfahren, Anwendungen
Y1  - 2020
SN  - 978-3-658-29115-0
U6  - https://doi.org/10.1007/978-3-658-29116-7
N1  - gedruckt in der Bereichsbibliothek Eupener Str. unter der Signatur 21 XXA 15(6);
auch als Online-Ressource ISBN 978-3-658-29116-7
PB  - Springer Vieweg
CY  - Wiesbaden
ET  - 6., überarbeitete Auflage
ER  - 
TY  - CHAP
A1  - Müller, Tim M.
A1  - Altherr, Lena
A1  - Leise, Philipp
A1  - Pelz, Peter F.
T1  - Optimization of pumping systems for buildings: Experimental validation of different degrees of model detail on a modular test rig
T2  - Operations Research Proceedings 2019
N2  - Successful optimization requires an appropriate model of the system under consideration. When selecting a suitable level of detail, one has to consider solution quality as well as the computational and implementation effort. In this paper, we present a MINLP for a pumping system for the drinking water supply of high-rise buildings. We investigate the influence of the granularity of the underlying physical models on the solution quality. Therefore, we model the system with a varying level of detail regarding the friction losses, and conduct an experimental validation of our model on a modular test rig. Furthermore, we investigate the computational effort and show that it can be reduced by the integration of domain-specific knowledge.
KW  - Experimental validation
KW  - MINLP
KW  - Engineering optimization
KW  - Water supply system
KW  - Network design
Y1  - 2020
SN  - 978-3-030-48438-5
U6  - https://doi.org/10.1007/978-3-030-48439-2_58
N1  - Annual International Conference of the German Operations Research Society (GOR), Dresden, Germany, September 4-6, 2019
SP  - 481
EP  - 488
PB  - Springer
CY  - Cham
ER  - 
TY  - JOUR
A1  - Müller, Tim M.
A1  - Leise, Philipp
A1  - Lorenz, Imke-Sophie
A1  - Altherr, Lena
A1  - Pelz, Peter F.
T1  - Optimization and validation of pumping system design and operation for water supply in high-rise buildings
JF  - Optimization and Engineering
N2  - The application of mathematical optimization methods for water supply system design and operation provides the capacity to increase the energy efficiency and to lower the investment costs considerably. We present a system approach for the optimal design and operation of pumping systems in real-world high-rise buildings that is based on the usage of mixed-integer nonlinear and mixed-integer linear modeling approaches. In addition, we consider different booster station topologies, i.e. parallel and series-parallel central booster stations as well as decentral booster stations. To confirm the validity of the underlying optimization models with real-world system behavior, we additionally present validation results based on experiments conducted on a modularly constructed pumping test rig. Within the models we consider layout and control decisions for different load scenarios, leading to a Deterministic Equivalent of a two-stage stochastic optimization program. We use a piecewise linearization as well as a piecewise relaxation of the pumps’ characteristics to derive mixed-integer linear models. Besides the solution with off-the-shelf solvers, we present a problem specific exact solving algorithm to improve the computation time. Focusing on the efficient exploration of the solution space, we divide the problem into smaller subproblems, which partly can be cut off in the solution process. Furthermore, we discuss the performance and applicability of the solution approaches for real buildings and analyze the technical aspects of the solutions from an engineer’s point of view, keeping in mind the economically important trade-off between investment and operation costs.
KW  - Technical Operations Research
KW  - MINLP
KW  - MILP
KW  - Experimental validation
KW  - Pumping systems
Y1  - 2020
U6  - https://doi.org/10.1007/s11081-020-09553-4
SN  - 1573-2924
VL  - 2021
IS  - 22
SP  - 643
EP  - 686
PB  - Springer
ER  - 
TY  - CHAP
A1  - Nees, Franz
A1  - Stengel, Ingo
A1  - Meister, Vera G.
A1  - Barton, Thomas
A1  - Herrmann, Frank
A1  - Müller, Christian
A1  - Wolf, Martin R.
T1  - Angewandte Forschung in der Wirtschaftsinformatik 2020 : Tagungsband zur 33. AKWI-Jahrestagung am 14.09.2020, ausgerichtet von der Hochschule Karlsruhe - Wirtschaft und Technik / hrsg. von Franz Nees, Ingo Stengel, Vera G. Meister, Thomas Barton, Frank Herrmann, Christian Müller, Martin R. Wolf
N2  - Tagungsbeiträge aus den Bereichen KI, Prozessorganisation und Plattformen für Geschäftsprozesse, Sicherheit und Datenschutz sowie Prototypen und Modelle.
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:526-opus4-13840
SN  - 978-3-944330-66-2
N1  - 33. AKWI-Jahrestagung am 14.09.2020, ausgerichtet von der Hochschule Karlsruhe - Wirtschaft und Technik
PB  - mana-Buch
CY  - Heide
ER  - 
TY  - JOUR
A1  - Nobis, Moritz
A1  - Schmitt, Carlo
A1  - Schemm, Ralf
A1  - Schnettler, Armin
T1  - Pan-European CVAR-constrained stochastic unit commitment in day-ahead and intraday electricity markets
JF  - Energies
N2  - The fundamental modeling of energy systems through individual unit commitment decisions is crucial for energy system planning. However, current large-scale models are not capable of including uncertainties or even risk-averse behavior arising from forecasting errors of variable renewable energies. However, risks associated with uncertain forecasting errors have become increasingly relevant within the process of decarbonization. The intraday market serves to compensate for these forecasting errors. Thus, the uncertainty of forecasting errors results in uncertain intraday prices and quantities. Therefore, this paper proposes a two-stage risk-constrained stochastic optimization approach to fundamentally model unit commitment decisions facing an uncertain intraday market. By the nesting of Lagrangian relaxation and an extended Benders decomposition, this model can be applied to large-scale, e.g., pan-European, power systems. The approach is applied to scenarios for 2023—considering a full nuclear phase-out in Germany—and 2035—considering a full coal phase-out in Germany. First, the influence of the risk factors is evaluated. Furthermore, an evaluation of the market prices shows an increase in price levels as well as an increasing day-ahead-intraday spread in 2023 and in 2035. Finally, it is shown that intraday cross-border trading has a significant influence on trading volumes and prices and ensures a more efficient allocation of resources.
Y1  - 2020
U6  - https://doi.org/10.3390/en13092339
SN  - 1996-1073
N1  - Special Issue Uncertainties and Risk Management in Competitive Energy Markets
VL  - 13
IS  - Art. 2339
SP  - 1
EP  - 35
PB  - MDPI
CY  - Basel
ER  - 
TY  - CHAP
A1  - Oetringer, Kerstin
A1  - Dümmler, Andreas
A1  - Göttsche, Joachim
T1  - Neues Modell zur 1D-Simulation der indirekten Verdunstungskühlung
T2  - DKV‐Tagung 2020, AA II.1
N2  - Im Projekt Coolplan‐ AIR geht es um die Fortentwicklung und Feld‐ Validierung eines Berechnungs‐ und Auslegungstools zur energieeffizienten Kühlung von Gebäuden mit luftgestützten Systemen. Neben dem Aufbau und der Weiterentwicklung von Simulationsmodellen erfolgen Vermessungen der Gesamtsysteme anhand von Praxisanlagen im Feld. Eine der betrachteten Anlagen arbeitet mit indirekter Verdunstung. Diese Veröffentlichung zeigt den Entwicklungsprozess und den Aufbau des Simulationsmodells zur Verdunstungskühlung in der Simulationsumgebung Matlab‐ Simulink mit der CARNOT‐ Toolbox. Das besondere Augenmerk liegt dabei auf dem physikalischen Modell des Wärmeübertragers, in dem die Verdunstung implementiert ist. Dem neuen Modellansatz liegt die Annahme einer aus der Enthalpie‐ Betrachtung hergeleiteten effektiven Wärmekapazität zugrunde. Des Weiteren wird der Befeuchtungsgrad als konstant angesehen und eine standardisierte Zunahme der Wärmeübertragung des feuchten gegenüber dem trockenen Wärmeübertrager angenommen. Die Validierung des Modells erfolgte anhand von Literaturdaten. Für den trockenen Wärmetauscher ist der maximale absolute Fehler der berechneten Austrittstemperatur (Zuluft) kleiner als ±0.1 K und für den nassen Wärmetauscher (Kühlfall) unter der Annahme eines konstanten Verdunstungsgrades kleiner als ±0.4 K.
Y1  - 2020
N1  - Deutsche Kälte- und Klimatagung, 19-20 November 2020, online
SP  - 250
EP  - 262
ER  - 
TY  - GEN
A1  - Ohrtmann, Jan-Peter
A1  - Golland, Alexander
T1  - Daten- und Privatsphäreschutz im Wandel der 2020er-Jahre
Y1  - 2020
SP  - 33
EP  - 38
ER  -