TY - JOUR A1 - Berndt, Heinz A1 - Klostermeyer, Henning A1 - Zahn, Helmut T1 - Zur Synthese monomerer cyclischer Cystinpeptidderivate, I : Synthese der Sequenz A 6–9 des Schafinsulins als Cyclocystinylderivat JF - Justus Liebigs Annalen der Chemie N2 - Es wird die Synthese der Sequenz A 6–9 des Schafinsulins in der geschützten Form Boc-Cys-Cys-Ala-Gly-OBuᵗ (5) sowie das Verhalten dieses monomeren cyclischen Cystinpeptidderivates gegenüber den in der Peptidchemie gebräuchlichen Reagenzien Bortrifluorid/Eisessig, Triäthylamin und Hydrazinhydrat beschrieben. Y1 - 1972 U6 - https://doi.org/10.1002/jlac.19727590109 SN - 1099-0690 VL - 759 IS - 1 SP - 114 EP - 120 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Berndt, Heinz A1 - Gattner, Hans-Gregor A1 - Zahn, Helmut T1 - Semisynthetisches Des-A1-glycin-Schafinsulin JF - Biological Chemistry Y1 - 1975 U6 - https://doi.org/10.1515/bchm2.1975.356.2.1455 SN - 1437-4315 VL - 356 IS - 2 SP - 1469 EP - 1472 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Berndt, Heinz T1 - Synthese der Sequenz 71—86 des Humanproinsulins, I : Synthese der Sequenz 71—86 als monomeres cyclisches Biscystinpeptidderivat und als Tetra-S-tritylderivat JF - Hoppe-Seyler's Zeitschrift für physiologische Chemie Y1 - 1979 U6 - https://doi.org/10.1515/bchm2.1979.360.1.747 SN - 1437-4315 SN - 0018-4888 VL - 360 IS - 1 SP - 747 EP - 760 ER - TY - JOUR A1 - Berndt, Heinz T1 - Synthese der Sequenz 71—86 des Humanproinsulins, III : Synthese über die Fragmente 71—78 und 79—86 JF - Hoppe-Seyler's Zeitschrift für physiologische Chemie Y1 - 1979 U6 - https://doi.org/10.1515/bchm2.1979.360.1.765 SN - 1437-4315 SN - 0018-4888 VL - 360 IS - 1 SP - 765 EP - 772 ER - TY - JOUR A1 - Berndt, Heinz T1 - Zur Reaktion von Iminodithiocarbonaten mit Carbonsäuren. I : Synthese des Modellpeptid-Derivates Z-(L)-Ala-(L/D)-Phe-(L)-Val-OMe JF - Tetrahedron letters Y1 - 1980 U6 - https://doi.org/10.1016/S0040-4039(00)78663-1 SN - 0040-4039 VL - 21 IS - 34 SP - 3265 EP - 3268 ER - TY - JOUR A1 - Bernau, C. R. A1 - Knödler, Matthias A1 - Emonts, Jessica A1 - Jäpel, Ronald Colin A1 - Buyel, Johannes Felix T1 - The use of predictive models to develop chromatography-based purification processes JF - Frontiers in Bioengineering and Biotechnology N2 - Chromatography is the workhorse of biopharmaceutical downstream processing because it can selectively enrich a target product while removing impurities from complex feed streams. This is achieved by exploiting differences in molecular properties, such as size, charge and hydrophobicity (alone or in different combinations). Accordingly, many parameters must be tested during process development in order to maximize product purity and recovery, including resin and ligand types, conductivity, pH, gradient profiles, and the sequence of separation operations. The number of possible experimental conditions quickly becomes unmanageable. Although the range of suitable conditions can be narrowed based on experience, the time and cost of the work remain high even when using high-throughput laboratory automation. In contrast, chromatography modeling using inexpensive, parallelized computer hardware can provide expert knowledge, predicting conditions that achieve high purity and efficient recovery. The prediction of suitable conditions in silico reduces the number of empirical tests required and provides in-depth process understanding, which is recommended by regulatory authorities. In this article, we discuss the benefits and specific challenges of chromatography modeling. We describe the experimental characterization of chromatography devices and settings prior to modeling, such as the determination of column porosity. We also consider the challenges that must be overcome when models are set up and calibrated, including the cross-validation and verification of data-driven and hybrid (combined data-driven and mechanistic) models. This review will therefore support researchers intending to establish a chromatography modeling workflow in their laboratory. KW - biopharmaceutical production process KW - Data-driven models KW - downstream processing design KW - experiment quality KW - hybrid model validation Y1 - 2022 U6 - https://doi.org/10.3389/fbioe.2022.1009102 SN - 2296-4185 (online-ressource) IS - 10 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Bergs, Michel A1 - Monakhova, Yulia A1 - Diehl, Bernd W. A1 - Konow, Christopher A1 - Völkering, Georg A1 - Pude, Ralf A1 - Schulze, Margit T1 - Lignins isolated via catalyst-free organosolv pulping from Miscanthus x giganteus, M. sinensis, M. robustus and M. nagara: a comparative study JF - Molecules N2 - As a low-input crop, Miscanthus offers numerous advantages that, in addition to agricultural applications, permits its exploitation for energy, fuel, and material production. Depending on the Miscanthus genotype, season, and harvest time as well as plant component (leaf versus stem), correlations between structure and properties of the corresponding isolated lignins differ. Here, a comparative study is presented between lignins isolated from M. x giganteus, M. sinensis, M. robustus and M. nagara using a catalyst-free organosolv pulping process. The lignins from different plant constituents are also compared regarding their similarities and differences regarding monolignol ratio and important linkages. Results showed that the plant genotype has the weakest influence on monolignol content and interunit linkages. In contrast, structural differences are more significant among lignins of different harvest time and/or season. Analyses were performed using fast and simple methods such as nuclear magnetic resonance (NMR) spectroscopy. Data was assigned to four different linkages (A: β-O-4 linkage, B: phenylcoumaran, C: resinol, D: β-unsaturated ester). In conclusion, A content is particularly high in leaf-derived lignins at just under 70% and significantly lower in stem and mixture lignins at around 60% and almost 65%. The second most common linkage pattern is D in all isolated lignins, the proportion of which is also strongly dependent on the crop portion. Both stem and mixture lignins, have a relatively high share of approximately 20% or more (maximum is M. sinensis Sin2 with over 30%). In the leaf-derived lignins, the proportions are significantly lower on average. Stem samples should be chosen if the highest possible lignin content is desired, specifically from the M. x giganteus genotype, which revealed lignin contents up to 27%. Due to the better frost resistance and higher stem stability, M. nagara offers some advantages compared to M. x giganteus. Miscanthus crops are shown to be very attractive lignocellulose feedstock (LCF) for second generation biorefineries and lignin generation in Europe. Y1 - 2021 U6 - https://doi.org/10.3390/molecules26040842 SN - 1420-3049 N1 - Special Issue Lignin – A Natural Resource with Huge Potential https://www.mdpi.com/journal/molecules/special_issues/lignin_natural VL - 26 IS - 4 PB - MDPI CY - Basel ER - TY - JOUR A1 - Bergmann, Sandra A1 - Demuth, Bastian A1 - Sander, Volker T1 - A Web Framework for Workflow Submission and Monitoring via UNICORE 6 based on Distributable Scientific Workflow Templates JF - UNICORE Summit 2011 : proceedings, 7-8 July 2011, Torun, Poland / Mathilde Romberg ... (Eds.) Y1 - 2011 SN - 9783893367504 N1 - UNICORE Summit ; (2011 ; 2011.07.07-08 ; Torun) ; Schriften des Forschungszentrums Jülich IAS Series 9 SP - 45 EP - 50 PB - Forschungszentrum Jülich CY - Jülich ER - TY - JOUR A1 - Bergmann, Ole A1 - Möhren, Felix A1 - Braun, Carsten A1 - Janser, Frank T1 - On the influence of elasticity on swept propeller noise JF - AIAA SCITECH 2023 Forum N2 - High aerodynamic efficiency requires propellers with high aspect ratios, while propeller sweep potentially reduces noise. Propeller sweep and high aspect ratios increase elasticity and coupling of structural mechanics and aerodynamics, affecting the propeller performance and noise. Therefore, this paper analyzes the influence of elasticity on forward-swept, backward-swept, and unswept propellers in hover conditions. A reduced-order blade element momentum approach is coupled with a one-dimensional Timoshenko beam theory and Farassat's formulation 1A. The results of the aeroelastic simulation are used as input for the aeroacoustic calculation. The analysis shows that elasticity influences noise radiation because thickness and loading noise respond differently to deformations. In the case of the backward-swept propeller, the location of the maximum sound pressure level shifts forward by 0.5 °, while in the case of the forward-swept propeller, it shifts backward by 0.5 °. Therefore, aeroacoustic optimization requires the consideration of propeller deformation. Y1 - 2023 U6 - https://doi.org/10.2514/6.2023-0210 N1 - Session: Propeller, Open Rotor, and Rotorcraft Noise II AIAA SCITECH 2023 Forum, 23-27 January 2023, National Harbor, MD & Online PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Bergmann, Ole A1 - Götten, Falk A1 - Braun, Carsten A1 - Janser, Frank T1 - Comparison and evaluation of blade element methods against RANS simulations and test data JF - CEAS Aeronautical Journal N2 - This paper compares several blade element theory (BET) method-based propeller simulation tools, including an evaluation against static propeller ground tests and high-fidelity Reynolds-Average Navier Stokes (RANS) simulations. Two proprietary propeller geometries for paraglider applications are analysed in static and flight conditions. The RANS simulations are validated with the static test data and used as a reference for comparing the BET in flight conditions. The comparison includes the analysis of varying 2D aerodynamic airfoil parameters and different induced velocity calculation methods. The evaluation of the BET propeller simulation tools shows the strength of the BET tools compared to RANS simulations. The RANS simulations underpredict static experimental data within 10% relative error, while appropriate BET tools overpredict the RANS results by 15–20% relative error. A variation in 2D aerodynamic data depicts the need for highly accurate 2D data for accurate BET results. The nonlinear BET coupled with XFOIL for the 2D aerodynamic data matches best with RANS in static operation and flight conditions. The novel BET tool PropCODE combines both approaches and offers further correction models for highly accurate static and flight condition results. KW - BET KW - CFD propeller simulation KW - Propeller aerodynamics KW - Actuator disk modelling KW - Propeller performance Y1 - 2022 U6 - https://doi.org/10.1007/s13272-022-00579-1 SN - 1869-5590 (Online) SN - 1869-5582 (Print) N1 - Corresponding author: Ole Bergmann VL - 13 SP - 535 EP - 557 PB - Springer CY - Wien ER -