A5035251628- Molten salt chemistry and electrochemical processes
- Advanced Battery Materials and Technologies
- Extraction and Separation Processes
- Metallurgical Processes and Thermodynamics
- Meningioma and schwannoma management
- Neurofibromatosis and Schwannoma Cases
- Advanced Battery Technologies Research
- Vascular Malformations Diagnosis and Treatment
- Solar and Space Plasma Dynamics
- Hydrogen Storage and Materials
- Muscle activation and electromyography studies
- Geomagnetism and Paleomagnetism Studies
- Ocular Oncology and Treatments
- Fluid Dynamics and Mixing
- Fluid Dynamics and Heat Transfer
- Thermodynamic and Structural Properties of Metals and Alloys
- Scientific Research and Discoveries
- Characterization and Applications of Magnetic Nanoparticles
- Power Transformer Diagnostics and Insulation
- Botulinum Toxin and Related Neurological Disorders
- Ophthalmology and Eye Disorders
- Vestibular and auditory disorders
- Electrostatics and Colloid Interactions
- Astro and Planetary Science
- Balance, Gait, and Falls Prevention
Helmholtz-Zentrum Dresden-Rossendorf
2017-2025
Tel Aviv University
2022-2024
University of Rochester
2021
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2018
German Sport University Cologne
1999
Swiss Paraplegic Center
1994
Good Samaritan Hospital
1992
University of Freiburg
1984-1988
Abstract We propose a self-consistent explanation of Rieger-type periodicities, the Schwabe cycle, and Suess-de Vries cycle solar dynamo in terms resonances various wave phenomena with gravitational forces exerted by orbiting planets. Starting on high-frequency side, we show that two-planet spring tides Venus, Earth, Jupiter are able to excite magneto-Rossby waves, which can be linked typical periods. argue then 11.07-year beat period those waves synchronizes an underlying conventional...
In 15 patients with spastic hemiparesis the development of tension calf muscles in relation to their electrical activation and stretching period was studied on both sides during locomotion. Only leg did isolated small biphasic potentials appear gastrocnemius E.M.G. monosynaptic latency at beginning stance phase, while remaining reduced compared unaffected side. Perturbations gait were followed by a large response, polysynaptic reflex response reduced. only strong appeared, which suggests...
Liquid metal batteries (LMBs) are discussed today as a cheap grid scale energy storage, required for the deployment of fluctuating renewable energies. Built stable density stratification two liquid metals separated by thin molten salt layer, LMBs susceptible to short-circuit fluid flows. Using direct numerical simulation, we study sloshing long wave interface instability in cylindrical cells, which is already known from aluminium reduction cells. After characterising mechanism, investigate...
We investigate the coupling dynamics of interfacial waves in liquid metal batteries and its effects on battery’s operation safety. Similar to aluminium reduction cells, can be highly susceptible magnetohydrodynamically exited instabilities. The resulting are capable provoking short-circuits. Owing presence two metal-electrolyte interfaces that may step into resonance, wave is particularly complex. In first part this paper, we present a potential flow analysis coupled gravity–capillary waves....
Abstract The high electrolytic currents in aluminum reduction cells can provoke magnetohydrodynamic wave instabilities the liquid-liquid cryolite-Al interface. Most critical for safe operation of smelters is metal pad roll (MPR) instability, which set interface into self-growing rotational motions. Such are commonly averted by keeping poorly conducting cryolite layer sufficiently thick, but at detriment energy efficiency. Mohammad et al. (in: Eskin (ed) Light Metals 2022. Minerals, &...
Abstract Can atmospheric waves in planet-hosting solar-like stars substantially resonate to tidal forcing, perhaps at a level of impacting the space weather or even being dynamo-relevant? In particular, low-frequency Rossby waves, which have been detected solar near-surface layers, are predestined respond sunspot cycle-scale perturbations. this paper, we seek address these questions as formulate forced wave model for tachocline layer, is widely considered birthplace several...
Liquid metal batteries are possible candidates for massive and economically feasible large-scale stationary storage as such could be key components of future energy systems based mainly or exclusively on intermittent renewable electricity sources. The completely liquid interior the high current densities give rise to a multitude fluid flow phenomena that will primarily influence operation large cells, but might important today's smaller cells well. paper at hand starts with discussion...
We present an experimental and theoretical study of interfacial waves generated in a two-phase swirling flow by low-frequency (1 - 10 Hz) rotating magnetic field (RMF) oriented parallel to the interface. In contrast surface excited axial fields, we find that first dominant wave mode resembles hyperbolic paraboloid. A good agreement experiment with linearized model was obtained. These results can have important implications for metallurgical processes point way further research dynamics swirl...
We propose a new theoretical model for metal pad roll instability in idealized cylindrical reduction cells. In addition to the usual destabilizing effects, we viscous and Joule dissipation some capillary effects. The resulting explicit formulas are used as benchmarks two multiphase magnetohydrodynamic solvers, OpenFOAM SFEMaNS. Our formula damping rate of gravity waves cylinders with fluid layers compares excellently experimental measurements. use our locate viscously controlled threshold...
Electrocapillary flows in a classical experiment of Melcher and Taylor are studied. The computed streamlines qualitatively represent the experimental image. With increase electrocapillary forcing, main circulation localizes near boundary with larger electric potential. When dielectric liquid is replaced by poorly conducting one, system becomes non-isothermal owing to Joule heating, flow driven also buoyancy thermocapillary convection. results show that consideration two-phase model...
Liquid metal batteries have been introduced as promising option to address the needs for new energy storage technologies. Currently, based on sodium and zinc are under development a favorable due their high theoretical cell potential, readily abundant materials, cost-advantages. Nevertheless, they face problem of self-discharge, which makes it inevitable understand fluid dynamics in whole cell. Motivated by that, several types mechanic instabilities Na-Zn liquid identified discussed here. On...
The aim of this non-comparative, consecutive case series is to evaluate the short-term results after endoresection large uveal melanomas in combination with pretreatment stereotactic gamma knife radiosurgery.Between March 2000 and November 2002, forty-six patients underwent radiosurgery followed by tumour via a standard three-port vitrectomy including laser photocoagulation silicone oil tamponade. average height was 9.5 mm. minimum dose delivered volume 25 Gy.The median follow-up time 410...
The lowest swirling wave mode arising in upright circular cylinders as a response to orbital excitation has been widely studied the last decade, largely due its high practical relevance for orbitally shaken bioreactors. Our recent theoretical study (Horstmann et al. , J. Fluid Mech. vol. 891, 2020, A22) revealed damping-induced symmetry breaking mechanism that can cause spiral structures manifested so far disregarded higher rotating modes. Building on this work, we develop linear criterion...
When liquid metal batteries are charged or discharged, strong electrical currents passing through the three layers that we find in their interior. This may result pad roll instability drives gravity waves on interfaces between layers. In this paper, investigate theoretically idealised cylindrical were simulated previously by Weber et al. ( Phys. Fluids , vol. 29, no. 5, 2017 b 054101) and Horstmann J. Fluid Mech. 845, 2018, pp. 1–35). Near threshold, expect weakly destabilised waves,...
Interfacial waves arising in a two-phase swirling flow driven by low-frequency rotating magnetic field (RMF) are studied. At low RMF frequencies, of the order 1-10 Hz, oscillatory part induced Lorenz force becomes comparable to time-averaged one, and cannot be neglected. In particular, when free surfaces or two-liquid stably stratified systems subject RMF, pressure variations necessarily excite free-surface/interfacial waves, which can improve mass transfer different metallurgical processes....
We examine a remarkable consistency of the power spectrum paleoclimatic varved sediment data from Lake Lisan [1] with that novel solar dynamo model is doubly synchronized by tidal effects and revolution Sun around barycenter system [2,3]. support specify latter quantifying excitation magneto-Rossby waves [4] at tachocline estimating spin-orbit coupling. Typical time series resulting this are then utilized in double regression anthropogenic influences on global temperature past 170 years...