bluuebunny/crossref_metadata_2025_split huggingface dataset:
On systematic effects in the numerical solutions of the JIMWLK equation
Authors: Calì Salvatore , Cichy Krzysztof , Korcyl Piotr , Kotko Piotr , Kutak Krzysztof , Marquet Cyrille 
Published: July 2021

AbstractIn the high energy limit of hadron collisions, the evolution of the gluon density in the longitudinal momentum fraction can be deduced from the Balitsky hierarchy of equations or, equivalently, from the nonlinear Jalilian–Marian–Iancu–McLerran–Weigert–Leonidov–Kovner (JIMWLK) equation. The solutions of the latter can be studied numerically by using its reformulation in terms of a Langevin equation. In this paper, we present a comprehensive study of systematic effects associated with the numerical framework, in particular the ones related to the inclusion of the running coupling. We consider three proposed ways in which the running of the coupling constant can be included: “square root” and “noise” prescriptions and the recent proposal by Hatta and Iancu. We implement them both in position and momentum spaces and we investigate and quantify the differences in the resulting evolved gluon distributions. We find that the systematic differences associated with the implementation technicalities can be of a similar magnitude as differences in running coupling prescriptions in some cases, or much smaller in other cases.
Guglielmo Marconi, Augusto Righi and the invention of wireless telegraphy
Authors: Leone Matteo , Robotti Nadia 
Published: July 2021

AbstractOne of the major accomplishments of the late nineteenth-century applied physics was, as it is well known, the development of wireless telegraphy by Guglielmo Marconi, future Nobel laureate. In this paper, we will explore what scientific debt, if any, Marconi had toward another Italian physicist, internationally well known for his research on electromagnetic waves: Augusto Righi. This question will be pursued through a close analysis of Marconi’s first patent, of Righi’s scientific correspondence and of the specialized and popular press of the time. At the end of this analysis, which includes a brief survey of Marconi and Righi’s activity as senators of the Kingdom of Italy, we will better appreciate what Marconi took from contemporary scientists, what specific contributions he is responsible for and, ultimately, what Marconi and Righi thought of each other.
Highly Efficient SOFC System with Mk35x-Stack Module Operated with Gasified Biomass - HieffBioPower -
Authors: Megel Stefan , Schnetter Jens , Hielscher Sebastian , Kusnezoff Mihails , Dumboeck Ortwin , Weissensteiner Stephan , Sallai Christopher , Hauth Martin , Supancic Klaus , Biedermann Friedrich , Brunner Thomas , Obernberger Ingwald 
Published: July 2021

A stationary SOFC system utilizing gas from a biomass updraft gasifier is under development within the project “HiEffBioPower” by MAWERA, BIOS, Bosal, AVL, Calida Cleantech, Fraunhofer IKTS, Wuppertal Institute and University Utrecht (European Union Horizon2020 No. 727330). The system is based on Mk352-CFY-stack with Chromium based (CFY) interconnects and electrolyte supported cells. These stacks are robust, redox stable and demonstrated low degradation rates. The stacks are arranged to modules of eight 30-cell stacks and are electrically connected in series. The stack module was pre-tested at the test rig at IKTS and showed performance in accordance with system requirements. Stationary power points were measured to compare the behaviour of the stack module with the system tests at MAWERA. AVL designed and installed the overall SOFC system (heat exchangers, stack, catalytic afterburner, process control and visualisation) with a nominal capacity of 6 kWel. After shipping all parts of the SOFC system to MAWERA in Hard (AT), the coupling of the biomass gasifier, the gas cleaning unit and the SOFC system was conducted. The system is operated by an automated process control. The highest efforts needed the novel gas cleaning unit, consisting of a high temperature filter, a desulphurisation unit as well as a novel catalytic gas reforming stage developed by BIOS.
The biomass gasifier has been operated with wood chips of different quality. The high tar contents of the product gas make a tar cracking essential to reach a high calorific value of the gas for the SOFC system. The novel gas cleaning system shows good performance and reaches the defined SOFC requirements. The SOFC system developed and operated by AVL reached stable conditions for several days. The operating results of the stack module at lab conditions and at the real system are in a good agreement. The SOFC stack module performance in terms of cell voltages, stack temperature distribution and fuel utilization under biomass reformate fuel will be shown and supported by several simulation to get an overall energy balance. Examples of optimization for several components by CFD simulation and component tests will be given.
Influence of Oxygen Partial Pressure on Cathodic Polarization of LaNiO3/GDC Composite Cathode
Authors: Namioka Tomoaki , Hirota Tomohisa , Hashimoto Shin-ichi , Itoh Hibiki 
Published: July 2021

LaNiO3/GDC composite is one of the potential cathodic materials for intermediate temperature SOFCs. In order to evaluate its electrochemical performance, influence of oxygen partial pressure on cathodic polarization is examined with an electrolyte supported symmetric cell and a frequency response analyzer. An electrolyte disk made of GDC is used for the electrochemical symmetric cell. The operating temperature was controlled from 773K to 1073K, and the partial pressure was controlled between −4 < log(pO2) atm < 0 in this study.
Polarization resistance increased with decreasing oxygen partial pressure at any temperature. In addition, the characteristic frequency (the summit frequency) of the impedance arc decreased with decreasing oxygen partial pressure. In order to search for the reaction mechanism, the rate-determining step approximation is applied to the experimental results. As a result, a rate-determining step is not dissociative adsorption of oxygen, but apparent oxygen reduction (charge transfer) reaction at temperature in the range from 773K to 973K. However, activation energy of the interfacial conductivity which is a reciprocal of polarization resistance is lower than 100 kJ/mol. Therefore, the rate-determining step is presumably a surface diffusion step, which is a migration step of dissociative oxygen from active point on the LaNiO3 surface to double phase boundary. At 1073K and higher oxygen partial pressure condition, the rate-determination step is still apparent oxygen reduction (charge transfer) reaction. Whereas at 1073K and lower oxygen partial pressure condition, the rate-determining step may be dissociative adsorption of oxygen.
Optimization of SOFC Electrode Microstructures with Long Term Performance Modeling and Machine Learning
Authors: Epting William K , Lei Yinkai , Mason Jerry H , Abernathy Harry W. , Kalapos Thomas , Hackett Gregory A 
Published: July 2021

Performance degradation over time is a major barrier to the commercialization of solid oxide fuel cells (SOFCs). A major driver of this degradation is grain coarsening in the 3D microstructure of the porous, composite electrodes. The rate and extent of this microstructural degradation depends on the initial microstructure itself, raising the question of whether an optimal electrode microstructure can be determined for long-term performance. The high dimensionality of parameters that determine the initial microstructure makes parametric optimization challenging. In this work, we present a fully resolved 4D model for simulating microstructural and performance changes over 1,000 hours of cell operation by combining a phase-field coarsening model with spatially resolved microstructural analysis and continuum-level multiphysics performance modeling. The integrated model framework was run in a highly parallelized fashion to simulate the long-term performance of hundreds of LSM-YSZ cathodes and Ni-YSZ anodes. These electrode microstructures were synthetically generated to intentionally span 11 independent initial microstructural parameters. The results of the long-term performance model included electrochemical performance every 100 hours throughout the entire 1,000 hours of operation. Together with a novel figure of merit that accounts for both the initial and long-term performance, this high-dimensional bank of results was used to train a machine learning regression model. The machine learning model was trained to predict the long term performance based on the 11 independent initial microstructural parameters, allowing interpolation to values not included in the fully resolved models, as well as a more robust analysis of each parameter’s influence in this highly dimensional parameter space. A SHAP analysis [1] was performed on the trained machine learning model to determine the relative impact of each of the 11 independent initial microstructural parameters. This demonstrated that, for example, the LSM/YSZ ratio was the most impactful parameter in the cathode microstructure, with lower LSM/YSZ ratios generally leading to more energy produced over the cell’s lifetime. The fully trained model and SHAP analysis are also able to make specific recommendations for changes that would improve existing electrodes, providing a valuable tool for SOFC electrode developers and manufacturers.
[1] S. M. Lundberg, S-I. Lee. A Unified Approach to Interpreting Model Predictions. NIPS 2017.

Figure 1
1MW-Class Solid Oxide Electrolyser System Prototype for Low-Cost Green Hydrogen
Authors: Harman Jonathan , Hjalmarsson Per , Mermelstein Joshua , Ryley Joshua , Sadler Harry , Selby Mark 
Published: July 2021

Ceres has developed a novel and highly differentiated SteelCell™ solid oxide fuel cell technology based upon the use of thick-film ceramics deposited upon a ferritic stainless-steel substrate, using doped ceria as the predominant oxygen-ion conducting ceramic within the cell. The use of ceria allows operation of the SteelCell at lower temperatures (500 - 620 °C) than conventional SOFCs, and the use of a metal support allows much greater mechanical robustness and lower production cost than is typically the case with a planar ceramic SOFC, whilst maintaining the high volumetric power density typical of planar SOFCs.
Ceres Power are now qualifying their SteelCell™ technology for use in steam electrolysis operation with encouraging results. Tests suggest that functional electrochemical and physical processes of the SteelCell are equally efficient in SOFC and SOEC mode meaning there is no major difference in the area specific resistance and degradation within the nominal operating space.
As a next step, the development of a 1MW-class Solid Oxide Electrolysis (SOEL) system is proposed that offers a path to green hydrogen production costs of <$2/kgH2 with equally compelling capital equipment costs enabled by the SteelCell technology. One of the clear advantages of solid oxide electrolysis systems is the ability to thermally integrate with industrial processes such as steel, ammonia and e-fuels production. Integration with existing low pressure “waste” steam feeds available at industrial plants combined with available high grade heat streams may enable system efficiencies of greater than 90% to be achieved. A study of predicted system efficiencies and associated techno-economics of green hydrogen production under various industrial use cases is presented.
The first-of-a-kind 1MW-class Solid Oxide Electrolysis system under consideration will be packaged within a 40ft ISO shipping container and is expected to produce approximately 600 to 800kg of green hydrogen per day. The system will be made up of a number of Electrolysis Cell Modules (ECM). Each ECM will contain an array of Ceres’ standard Gen1B stacks along with hot balance of plant components such as heat exchangers and heaters. This modular approach allows each module to be constructed and tested prior to installation at the demonstration site. It also allows for a high degree of fault tolerance and redundancy that is particularly valuable for prototype systems. Furthermore, it also enables a distributed supply chain to be developed for various elements up and down the system structure.
Finally, a roadmap to the first commercial SOEL systems is presented setting out predicted system CapEx costs, hydrogen production costs and possible arrangements for systems in the 100+ MW range.
Development of Low-temperature SOECs with Excellent Performance for CO2 and H2O Co-Electrolysis
Authors: Shiming Hu , Li Yitong , Tian Yunfeng , Chi Bo , Pu Jian 
Published: July 2021

Because of the advantages of high efficiency, safety, pollution-free and the waste gas can be converted into clean fuel (such as methane) in situ [1], using the solid oxide electrolysis cells (SOECs) to co-electrolyze water and carbon dioxide to produce oxygen has great application potential in the aerospace field. As early as the 1960s, NASA has begun to research on the use of SOECs to supply oxygen to astronauts [2]. However, the existing SOECs can only operate in high temperature range (750~850 ºC) with short lifetime and high energy consumption [3]. Therefore, it is urgent to reduce the operating temperature of SOECs in order to extend the operating life and shorten its start-up time, then providing a feasibility guarantee for its service in the aerospace industry.
However, lowering the cells’ operating temperature will bring about the problem of low oxygen ion conductivity. There are two strategies to solve this problem. One is to select materials with high oxygen ion conductivity in the low temperature range; the other is to reduce the thickness of the electrolyte layer to shorten the mass transfer distance. Herein, GDC was selected as the thin electrolyte material. And by adjusting the paste ratio of screen-printing method and sintering process parameters, the thickness of the dense electrolyte layer can be reduced to <5 μm. Besides, Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) and GDC are mechanically mixed as the anode materials. The measured ohmic resistance and polarization resistance are only 0.079 and 0.019 Ω·cm2 at 650 ºC, and the maximum output power density reaches 1.229 W/cm2 in SOFC mode. In SOEC mode, the steam and carbon dioxide are injected into the cell at a volume ratio of 3:1. The output current density is as high as 1.2 A/cm2 at 650 ºC under an applied voltage of 1.1 V. All these results confirm that the cells are promising for the applications in low temperature SOECs.
References
[1] A. Hauch, R. Kungas, P. Blennow, A. B. Hansen, J. B. Hansen, B. V. Mathiesen, et al. Recent advances in solid oxide cell technology for electrolysis. Science, 2020, 370(6513).
[2] H. Xu, M. M. Maroto-Valer, M. Ni, J. Cao and J. Xuan. Low carbon fuel production from combined solid oxide CO2 co-electrolysis and Fischer-Tropsch synthesis system: A modelling study. Applied Energy, 2019, 242: 911-918.
[3] Y. Wang, W. Li, L. Ma, W. Li and X. Liu. Degradation of solid oxide electrolysis cells: Phenomena, mechanisms, and emerging mitigation strategies—A review. Journal of Materials Science & Technology, 2020, 55: 35-55.
B-Site Sc Doping of La0.6Ca0.4Fe0.8Ni0.2O3-
d as an Electrode for Solid Oxide Cells
Authors: Tian Yunfeng , Wang Xinxin , Ling Yihan , Chi Bo , Pu Jian 
Published: July 2021

Reversible solid oxide electrochemical cell (RSOC) is a competitive option which has attracted increasing focus on alleviating some environmental problems and energy crisis with the capability of reversibly operating in solid oxide fuel cell (SOFC) mode and solid oxide electrolysis cell (SOEC) mode [1].
Solid oxide cells (SOCs) have received increasingly attention due to their high efficiency and broad applications. However, electrodes with rapid hydrogen oxidation reaction (HOR), oxygen reduction reaction (ORR), carbon dioxide reduction reaction (CO2RR), oxygen evolution reaction (OER) and sufficient durability play a key role in solid oxide cells. A multifunctional perovskite oxide La0.6Ca0.4Fe0.8Ni0.2O3-δ (LCFN) has been investigated as an electrode for SSOCs in our previous work. The results confirm that LCFN shows excellent ORR, OER, CO2-RR and HOR catalytic activity [2-3]. However, the investigation of LCFN for SOCs has been hindered due to the lack of stability. Herein, a novel perovskite La0.6Ca0.4Fe0.7Sc0.1Ni0.2O3-δ (LCFSN) is investigated as an electrode of SOCs. Its structural stability has been improved under H2 atmosphere. The polarization resistance (Rp) of the electrode LCFSN is only 0.147 Ω cm2 at 800 °C under air. The single cell Ni-YSZ/YSZ/GDC/LCFSN displays a peak power density of 1.36 W/cm2 in fuel cell mode and a low Rp value of 0.131 Ω cm2. Most importantly, the cell exhibits admirable durability of 130 h without apparent degradation. All these results suggest that LCFSN is a promising candidate electrode for SOCs.
Properties and Performance of Electrolyte Supported SOFCs with EB-PVD Gd-Doped Ceria Thin-Films
Authors: Han Feng , Riegraf Matthias , Sata Noriko , Bombarda Ilaria , Liensdorf Tom , Sitzmann Carolin , Langhof Nico , Schafföner Stefan , Walter Christian , Geipel Christian , Costa Rémi 
Published: July 2021

High temperature solid oxide fuel cell (SOFC) is regarded as a unique electrochemical device to convert the chemical energy of a large diversity of fuels into electricity and heat with high efficiency and low emission. The electrolyte-supported cell (ESC) design is proven to be one of the most feasible SOFC technologies for commercial applications. Thickness reduction of yttria stabilized zirconia (YSZ) electrolyte supports without sacrifice of mechanical strength is favorable for cell performance enhancement.
In this work, dense gadolinium-doped ceria (GDC) thin-films with thickness in the range of 0.15-0.5 µm were fabricated as Sr-barrier layers on the cathode side, and as strength-balance and adhesion layer on the anode side by electron beam physical vapor deposition (EB-PVD) method. Replacing the state-of-the-art screen-printed GDC layers, the approach with YSZ substrate sandwiched in between two GDC thin-films was proposed not only to prevent the formation of interfacial secondary phase on the cathode side, but also to increase the overall robustness of ESCs. Investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), it was confirmed that 0.5 µm thick GDC thin-films were effective to suppress the formation of Sr-zirconate phase at the YSZ/GDC interface. In comparison to reference cells with screen-printed GDC layers, higher breaking loads were recorded on the cells with PVD-GDC thin-films by Ring-On-Ring bending tests, showing considerably improved mechanical properties. Current-voltage characteristics and electrochemical impedance spectroscopy demonstrated that the performance of the as-prepared ESCs with GDC thin-films was comparable to the reference cells. Operated at 860 °C, the ESC with 0.5 µm GDC thin-film outperformed other tested cells with 0.15 µm or 0.3 µm GDC layers, and delivered a power density of 0.55 W•cm-2 at a cell voltage of 0.7 V. The results achieved in this work can be considered as step stones for the further development of ESCs with reduced electrolyte thickness, sufficient robustness and improved performance.
This work is financially supported by the German Ministry for Economic Affairs and Energy (BMWi) within the framework of the project “Kostenoptimierter Stack und verbessertes Offgrid-System (KOSOS)” with grant number of 03ETB005C.
A High Performance La0.2Sr0.8Co0.8Fe0.2O3-δ Catalyst As an Oxygen Electrode for Reversible Solid Oxide Cells at Intermediate Temperature
Authors: KIM Doyeub , Park Jin Wan , Chae Munseok S , Jung Incheol , Park Jeong Hwa , Kim Kyeong Joon , Lee Jong Jun , Jung Chanhoon , Lee Chan-Woo , Hong Seung-Tae , Lee Kang Taek 
Published: July 2021

Solid oxide cells (SOCs) have been reported as promising energy production and storage devices due to their high efficiency and low pollutant emissions. A key barrier to achieve high performance of SOCs is high electrode polarization resistance which attributes to the sluggish kinetics of oxygen reduction reactions (ORRs) and oxygen evolution reactions (OERs) at reduced temperatures. One of the potential oxygen electrodes is a perovskite La0.6Sr0.4Co0.2Fe0.8O3-
δ(LSCF6428) with mixed ionic and electronic conduction (MIEC) because of its considerable conductivities and good chemical compatibility with conventional electrolyte materials such as ceria-based oxides. However, upon long-term operation under fuel cell conditions, the LSCF6428 electrode is usually subjected to severe degradation of ORR kinetics owing to chemical instability. It has been well known that the tailoring the chemical composition of the perovskite material strongly modulates their electrochemical activities and oxygen ion transport properties.
In this study, we synthesized the La0.2Sr0.8Co0.8Fe0.2O3-
δ (LSCF2882) and systematically investigated its characteristics on intrinsic properties. In addition, we evaluated oxygen transport kinetics and electrochemical performance of LSCF2882 as an oxygen electrode for reversible SOC applications.
Quantitative Analysis of Solid-State Energy Devices Via 3D Reconstruction Using a FIB/SEM Dual Beam System
Authors: Bae Kyung Taek , Park Joonam , Joh Dong Woo , Park Jeong Hwa , Kim Dohwan , Jeong Wooyoung , Nam Ji-Eun , Lee Myeong Ju , Shin Dong Ok , Lee Yong Min , Lee Kang Taek 
Published: July 2021

To lower the carbon emission from the rising consumption of fossil fuels, electrochemical devices such as fuel cells and batteries, which can produce or store electricity from renewable resources, are attracting attention. Both systems require an electronically insulating solid membrane, which separates the cathode and anode to prevent short-circuiting. To improve the performance of porous electrodes, researchers have focused on tuning the electrode microstructure. The addition of highly ionic conducting materials to the electrode is commonly used to maximize the reaction site density. However, microstructural features, such as particle size distribution, electrochemically active site density and connectivity of each phase, are difficult to quantify only using conventionally used characterization methods such as scanning electron microscopy (SEM).
One well-established method for obtaining three-dimensionally interconnected microstructural information is serial sectioning using a FIB/SEM dual beam system. Using this technique, more reliable and accurate quantification of the SOFC and ASSLIB electrodes microstructure are available. Also, the quantified features will be reflected in the responses of electrochemical impedance spectroscopy (EIS) measurements. These results can provide a link between them. Therefore, the aim of this study is to three-dimensionally reconstruct the microstructure of solid-state energy devices via FIB/SEM dual beam system and to quantify their microstructural features. Also, these results will be combined with the electrochemically analyzed properties to further understanding their relationship with microstructural properties.