TY  - JOUR
A1  - Dellmann, Sophia Florence
A1  - Glorius, J.
A1  - Litvinov, Yu A.
A1  - Reifarth, R.
A1  - Al-Khasawneh, Kafa
A1  - Aliotta, M.
A1  - Bott, L.
A1  - Brückner, Benjamin
A1  - Bruno, C. G.
A1  - Chen, Ruijiu
A1  - Davinson, T.
A1  - Dickel, T.
A1  - Dillmann, Iris
A1  - Dmytriev, D.
A1  - Erbacher, P.
A1  - Freire-Fernández, D.
A1  - Forstner, Oliver
A1  - Geissel, H.
A1  - Göbel, K.
A1  - Griffin, Christopher J.
A1  - Grisenti, R.
A1  - Gumberidze, Alexandre
A1  - Haettner, Emma
A1  - Hagmann, Siegbert
A1  - Heil, M.
A1  - Heß, R.
A1  - Hillenbrand, P.-M.
A1  - Joseph, R.
A1  - Jurado, B.
A1  - Kozhuharov, Christophor
A1  - Kulikov, I.
A1  - Löher, Bastian
A1  - Langer, Christoph
A1  - Leckenby, Guy
A1  - Lederer-Woods, C.
A1  - Lestinsky, M.
A1  - Litvinov, S. A.
A1  - Lorenz, B. A.
A1  - Lorenz, E.
A1  - Marsh, J.
A1  - Menz, Esther Babette
A1  - Morgenroth, T.
A1  - Petridis, N.
A1  - Pibernat, Jerome
A1  - Popp, U.
A1  - Psaltis, Athanasios
A1  - Sanjari, Shahab
A1  - Scheidenberger, C.
A1  - Sguazzin, M.
A1  - Sidhu, Ragandeep Singh
A1  - Spillmann, Uwe
A1  - Steck, M.
A1  - Stöhlker, T.
A1  - Surzhykov, A.
A1  - Swartz, J. A.
A1  - Törnqvist, H.
A1  - Varga, L.
A1  - Vescovi, Diego
A1  - Weick, H.
A1  - Weigand, M.
A1  - Woods, P.
A1  - Xing, Y.
A1  - Yamaguchi, Taiyo
T1  - Proton capture on stored radioactive ¹¹⁸Te ions
JF  - EPJ Web of Conferences
N2  - Experimental determination of the cross sections of proton capture on radioactive nuclei is extremely difficult. Therefore, it is of substantial interest for the understanding of the production of the p-nuclei. For the first time, a direct measurement of proton-capture cross sections on stored, radioactive ions became possible in an energy range of interest for nuclear astrophysics. The experiment was performed at the Experimental Storage Ring (ESR) at GSI by making use of a sensitive method to measure (p,γ) and (p,n) reactions in inverse kinematics. These reaction channels are of high relevance for the nucleosyn-thesis processes in supernovae, which are among the most violent explosions in the universe and are not yet well understood. The cross section of the ¹¹⁸Te(p,γ) reaction has been measured at energies of 6 MeV/u and 7 MeV/u. The heavy ions interacted with a hydrogen gas jet target. The radiative recombination process of the fully stripped ¹¹⁸Te ions and electrons from the hydrogen target was used as a luminosity monitor. An overview of the experimental method and preliminary results from the ongoing analysis will be presented.
Y1  - 2023
U6  - https://doi.org/10.1051/epjconf/202327911018
SN  - 2100-014X
N1  - Volume 279, 2023. Nuclear Physics in Astrophysics – X (NPA-X 2022).
VL  - 279
IS  - Article Number: 11018
SP  - 1
EP  - 5
PB  - EDP Sciences
ER  - 
TY  - JOUR
A1  - Hoffstadt, Kevin
A1  - Cheenakula, Dheeraja
A1  - Nikolausz, Marcell
A1  - Krafft, Simone
A1  - Harms, Hauke
A1  - Kuperjans, Isabel
T1  - Design and construction of a new reactor for flexible biomethanation of hydrogen
JF  - Fermentation
N2  - The increasing share of renewable electricity in the grid drives the need for sufficient storage capacity. Especially for seasonal storage, power-to-gas can be a promising approach. Biologically produced methane from hydrogen produced from surplus electricity can be used to substitute natural gas in the existing infrastructure. Current reactor types are not or are poorly optimized for flexible methanation. Therefore, this work proposes a new reactor type with a plug flow reactor (PFR) design. Simulations in COMSOL Multiphysics ® showed promising properties for operation in laminar flow. An experiment was conducted to support the simulation results and to determine the gas fraction of the novel reactor, which was measured to be 29%. Based on these simulations and experimental results, the reactor was constructed as a 14 m long, 50 mm diameter tube with a meandering orientation. Data processing was established, and a step experiment was performed. In addition, a kLa of 1 h−1 was determined. The results revealed that the experimental outcomes of the type of flow and gas fractions are in line with the theoretical simulation. The new design shows promising properties for flexible methanation and will be tested.
KW  - methanation
KW  - plug flow reactor
KW  - bubble column
KW  - bio-methane
KW  - power-to-gas
Y1  - 2023
U6  - https://doi.org/10.3390/fermentation9080774
SN  - 2311-5637
N1  - The article belongs to the Special Issue Fermentation Processes: Modeling, Optimization and Control
VL  - 9
IS  - 8
SP  - 1
EP  - 16
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Trapp, Svenja
A1  - Lammers, Tom
A1  - Engudar, Gokce
A1  - Hoehr, Cornelia
A1  - Denkova, Antonia G.
A1  - Paulßen, Elisabeth
A1  - de Kruijff, Robin M.
T1  - Membrane-based microfluidic solvent extraction of Ga-68 from aqueous Zn solutions: towards an automated cyclotron production loop
JF  - EJNMMI Radiopharmacy and Chemistry
KW  - Microfluidic solvent extraction
KW  - Ga-68
KW  - Cyclotron production
KW  - Medical radionuclide production
KW  - Metal contaminants
Y1  - 2023
U6  - https://doi.org/10.1186/s41181-023-00195-2
SN  - 2365-421X
VL  - 2023
IS  - 8, Article number: 9
SP  - 1
EP  - 14
PB  - Springer Nature
ER  - 
TY  - JOUR
A1  - El Bergui, Omnia
A1  - Abouabdillah, Aziz
A1  - Bourioug, Mohamed
A1  - Schmitz, Dominik
A1  - Biel, Markus
A1  - Aboudrare, Abdellah
A1  - Krauss, Manuel
A1  - Jomaa, Ahlem
A1  - Romuli, Sebastian
A1  - Müller, Joachim
A1  - Fagroud, Mustapha
A1  - Bouabid, Rachid
T1  - Innovative solutions for drought: Evaluating hydrogel application on onion cultivation (Allium cepa) in Morocco
JF  - Water
N2  - Throughout the last decade, and particularly in 2022, water scarcity has become a critical concern in Morocco and other Mediterranean countries. The lack of rainfall during spring was worsened by a succession of heat waves during the summer. To address this drought, innovative solutions, including the use of new technologies such as hydrogels, will be essential to transform agriculture. This paper presents the findings of a study that evaluated the impact of hydrogel application on onion (Allium cepa) cultivation in Meknes, Morocco. The treatments investigated in this study comprised two different types of hydrogel-based soil additives (Arbovit® polyacrylate and Huminsorb® polyacrylate), applied at two rates (30 and 20 kg/ha), and irrigated at two levels of water supply (100% and 50% of daily crop evapotranspiration; ETc). Two control treatments were included, without hydrogel application and with both water amounts. The experiment was conducted in an open field using a completely randomized design. The results indicated a significant impact of both hydrogel-type dose and water dose on onion plant growth, as evidenced by various vegetation parameters. Among the hydrogels tested, Huminsorb® Polyacrylate produced the most favorable outcomes, with treatment T9 (100%, HP, 30 kg/ha) yielding 70.55 t/ha; this represented an increase of 11 t/ha as compared to the 100% ETc treatment without hydrogel application. Moreover, the combination of hydrogel application with 50% ETc water stress showed promising results, with treatment T4 (HP, 30 kg, 50%) producing almost the same yield as the 100% ETc treatment without hydrogel while saving 208 mm of water.
KW  - water economy
KW  - yield
KW  - deficit irrigation
KW  - hydrogel
KW  - onion
Y1  - 2023
U6  - https://doi.org/10.3390/w15111972
VL  - 15
IS  - 11
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Hafidi, Youssef
A1  - El Hatka, Hicham
A1  - Schmitz, Dominik
A1  - Krauss, Manuel
A1  - Pettrak, Jürgen
A1  - Biel, Markus
A1  - Ittobane, Najim
T1  - Sustainable soil additives for water and micronutrient supply: swelling and chelating properties of polyaspartic acid hydrogels utilizing newly developed crosslinkers
JF  - Gels
N2  - Drought and water shortage are serious problems in many arid and semi-arid regions. This problem is getting worse and even continues in temperate climatic regions due to climate change. To address this problem, the use of biodegradable hydrogels is increasingly important for the application as water-retaining additives in soil. Furthermore, efficient (micro-)nutrient supply can be provided by the use of tailored hydrogels. Biodegradable polyaspartic acid (PASP) hydrogels with different available (1,6-hexamethylene diamine (HMD) and L-lysine (LYS)) and newly developed crosslinkers based on diesters of glycine (GLY) and (di-)ethylene glycol (DEG and EG, respectively) were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) and regarding their swelling properties (kinetic, absorbency under load (AUL)) as well as biodegradability of PASP hydrogel. Copper (II) and zinc (II), respectively, were loaded as micronutrients in two different approaches: in situ with crosslinking and subsequent loading of prepared hydrogels. The results showed successful syntheses of di-glycine-ester-based crosslinkers. Hydrogels with good water-absorbing properties were formed. Moreover, the developed crosslinking agents in combination with the specific reaction conditions resulted in higher water absorbency with increased crosslinker content used in synthesis (10% vs. 20%). The prepared hydrogels are candidates for water-storing soil additives due to the biodegradability of PASP, which is shown in an exemple. The incorporation of Cu(II) and Zn(II) ions can provide these micronutrients for plant growth.
KW  - micronutrients
KW  - swelling properties
KW  - biodegradable polymers
KW  - hydrogels
KW  - superabsorbent polymers
KW  - glycine
KW  - polyaspartic acid
Y1  - 2024
U6  - https://doi.org/10.3390/gels10030170
SN  - 2310-2861
VL  - 10
IS  - 3
SP  - Artikel 170
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Hoffstadt, Kevin
A1  - Nikolausz, Marcell
A1  - Krafft, Simone
A1  - Bonatelli, Maria
A1  - Kumar, Vivekanantha
A1  - Harms, Hauke
A1  - Kuperjans, Isabel
T1  - Optimization of the ex situ biomethanation of hydrogen and carbon dioxide in a novel meandering plug flow reactor: start-up phase and flexible operation
JF  - Bioengineering
KW  - methanation
KW  - plug flow reactor
KW  - bubble column
KW  - biomethane
KW  - P2G
Y1  - 2024
U6  - https://doi.org/10.3390/bioengineering11020165
SN  - 2306-5354
VL  - 11
IS  - 2
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Adels, Klaudia
A1  - Monakhova, Yulia
T1  - Low-field NMR spectroscopic study of e-cigarettes: Is determination of only nicotine and organic carrier solvents possible?
JF  - Microchemical Journal
N2  - Electronic cigarettes (e-cigarettes) have become popular worldwide with the market growing exponentially in some countries. The absence of product standards and safety regulations requires urgent development of analytical methodologies for the holistic control of the growing diversity of such products. An approach based on low-field nuclear magnetic resonance (LF-NMR) at 80 MHz is presented for the simultaneous determination of key parameters: carrier solvents (vegetable glycerine (VG), propylene glycol (PG) and water), total nicotine as well as free-base nicotine fraction. Moreover, qualitative and quantitative determination of fourteen weak organic acids deliberately added to enhance sensory characteristics of e-cigarettes was possible. In most cases these parameters can be rapidly and conveniently determined without using any sample manipulation such as dilution, extraction or derivatization steps. The method was applied for 37 authentic e-cigarettes samples. In particular, eight different organic acids with the content up to 56 mg/mL were detected. Due to its simplicity, the method can be used in routine regulatory control as well as to study release behaviour of nicotine and other e-cigarettes constituents in different products.
KW  - Electronic cigarettes
KW  - Low field NMR
KW  - Carrier solvents
KW  - Free-base nicotine
KW  - Weak organic acids
Y1  - 2024
U6  - https://doi.org/10.1016/j.microc.2024.110859
SN  - 1095-9149
N1  - Corresponding author: Yulia Monakhova
VL  - 203
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Tix, Julian
A1  - Moll, Fabian
A1  - Krafft, Simone
A1  - Betsch, Matthias
A1  - Tippkötter, Nils
T1  - Hydrogen production from enzymatic pretreated organic waste with thermotoga neapolitana
JF  - Energies
N2  - Biomass from various types of organic waste was tested for possible use in hydrogen production. The composition consisted of lignified samples, green waste, and kitchen scraps such as fruit and vegetable peels and leftover food. For this purpose, the enzymatic pretreatment of organic waste with a combination of five different hydrolytic enzymes (cellulase, amylase, glucoamylase, pectinase and xylase) was investigated to determine its ability to produce hydrogen (H2) with the hydrolyzate produced here. In course, the anaerobic rod-shaped bacterium T. neapolitana was used for H2 production. First, the enzymes were investigated using different substrates in preliminary experiments. Subsequently, hydrolyses were carried out using different types of organic waste. In the hydrolysis carried out here for 48 h, an increase in glucose concentration of 481% was measured for waste loads containing starch, corresponding to a glucose concentration at the end of hydrolysis of 7.5 g·L−1. In the subsequent set fermentation in serum bottles, a H2 yield of 1.26 mmol H2 was obtained in the overhead space when Terrific Broth Medium with glucose and yeast extract (TBGY medium) was used. When hydrolyzed organic waste was used, even a H2 yield of 1.37 mmol could be achieved in the overhead space. In addition, a dedicated reactor system for the anaerobic fermentation of T. neapolitana to produce H2 was developed. The bioreactor developed here can ferment anaerobically with a very low loss of produced gas. Here, after 24 h, a hydrogen concentration of 83% could be measured in the overhead space.
KW  - Biological hydrogen
KW  - Organic waste
KW  - Dark fermentation
KW  - Hydrolysis
KW  - Pretreatment
Y1  - 2024
U6  - https://doi.org/10.3390/en17122938
SN  - 1996-1073
N1  - Corresponding author: Nils Tippkötter
VL  - 17
IS  - 12
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Oehlenschläger, Katharina
A1  - Volkmar, Marianne
A1  - Stiefelmaier, Judith
A1  - Langsdorf, Alexander
A1  - Holtmann, Dirk
A1  - Tippkötter, Nils
A1  - Ulber, Roland
T1  - New insights into the influence of pre-culture on robust solvent production of C. acetobutylicum
JF  - Applied Microbiology and Biotechnology
N2  - Clostridia are known for their solvent production, especially the production of butanol. Concerning the projected depletion of fossil fuels, this is of great interest. The cultivation of clostridia is known to be challenging, and it is difficult to achieve reproducible results and robust processes. However, existing publications usually concentrate on the cultivation conditions of the main culture. In this paper, the influence of cryo-conservation and pre-culture on growth and solvent production in the resulting main cultivation are examined. A protocol was developed that leads to reproducible cultivations of Clostridium acetobutylicum. Detailed investigation of the cell conservation in cryo-cultures ensured reliable cell growth in the pre-culture. Moreover, a reason for the acid crash in the main culture was found, based on the cultivation conditions of the pre-culture. The critical parameter to avoid the acid crash and accomplish the shift to the solventogenesis of clostridia is the metabolic phase in which the cells of the pre-culture were at the time of inoculation of the main culture; this depends on the cultivation time of the pre-culture. Using cells from the exponential growth phase to inoculate the main culture leads to an acid crash. To achieve the solventogenic phase with butanol production, the inoculum should consist of older cells which are in the stationary growth phase. Considering these parameters, which affect the entire cultivation process, reproducible results and reliable solvent production are ensured.
KW  - Pre-culture
KW  - Metabolic shift
KW  - Acid crash
KW  - C. acetobutylicum
KW  - ABE
KW  - Butanol
Y1  - 2024
U6  - https://doi.org/10.1007/s00253-023-12981-8
SN  - 1432-0614
VL  - 108
PB  - Springer
CY  - Berlin, Heidelberg
ER  - 
TY  - JOUR
A1  - Hengsbach, Jan-Niklas
A1  - Engel, Mareike
A1  - Cwienczek, Marcel
A1  - Stiefelmaier, Judith
A1  - Tippkötter, Nils
A1  - Ulber, Roland
T1  - Scalable unseparated bioelectrochemical reactors by using a carbon fiber brush as stirrer and working electrode
JF  - ChemElectroChem
N2  - The concept of energy conversion into platform chemicals using bioelectrochemical systems (BES) has gained increasing attention in recent years, as the technology simultaneously provides an opportunity for sustainable chemical production and tackles the challenge of Power-to-X technologies. There are many approaches to realize the industrial scale of BES. One concept is to equip standard bioreactors with static electrodes. However, large installations resulted in a negative influence on various reactor parameters. In this study, we present a new single-chamber BES based on a stirred tank reactor in which the stirrer was replaced by a carbon fiber brush, performing the functions of the working electrode and the stirrer. The reactor is characterized in abiotic studies and electro-fermentations with Clostridium acetobutylicum. Compared to standard reactors an increase in butanol production of 20.14±3.66 % shows that the new BES can be efficiently used for bioelectrochemical processes.
Y1  - 2023
U6  - https://doi.org/10.1002/celc.202300440
SN  - 2196-0216
VL  - 10
IS  - 21
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Mues genannt Koers, Lucas
A1  - McNeil, S. W.
A1  - Radchenko, V.
A1  - Paulßen, Elisabeth
A1  - Hoehr, Cornelia
T1  - Production of Co-58m in a siphon-style liquid target on a medical cyclotron
N2  - We present the production of 58mCo on a small, 13 MeV medical cyclotron utilizing a siphon style liquid target system. Different concentrated iron(III)-nitrate solutions of natural isotopic distribution were irradiated at varying initial pressures and subsequently separated by solid phase extraction chromatography. The radio cobalt (58m/gCo and 56Co) was successfully produced with saturation activities of (0.35 ± 0.03) MBq μA−1 for 58mCo with a separation recovery of (75 ± 2) % of cobalt after one separation step utilizing LN-resin.
Y1  - 2023
U6  - https://doi.org/10.1016/j.apradiso.2023.110734
SN  - 0969-8043
VL  - 195
IS  - Art. 110734
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Mues genannt Koers, Lucas
A1  - Prevost, David
A1  - Paulßen, Elisabeth
A1  - Hoehr, Cornelia
T1  - Density reduction effects on the production of [11C]CO2 in Nb-body targets on a medical cyclotron
N2  - Medical isotope production of 11C is commonly performed in gaseous targets. The power deposition of the proton beam during the irradiation decreases the target density due to thermodynamic mixing and can cause an increase of penetration depth and divergence of the proton beam. In order to investigate the difference how the target-body length influences the operation conditions and the production yield, a 12 cm and a 22 cm Nb-target body containing N2/O2 gas were irradiated using a 13 MeV proton cyclotron. It was found that the density reduction has a large influence on the pressure rise during irradiation and the achievable radioactive yield. The saturation activity of [11C]CO2 for the long target (0.083 Ci/μA) is about 10% higher than in the short target geometry (0.075 Ci/μA).
Y1  - 2023
U6  - https://doi.org/10.1016/j.apradiso.2023.110911
VL  - 199
IS  - Art. 110911
PB  - Elsevier
CY  - Amsterdam
ER  -