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Understanding the Component-Driven Influence on the Electrochemical Properties in Single-Ion Polymer Electrolytes for Sodium-Based Batteries
No full textState-of-the-Art of High-Power Gyro-Devices: 2025 Update of Experimental Results
No full textThis report presents an update of the experimental achievements published in the review “State-of-the-Art of High-Power Gyro-Devices and Free Electron Masers,” Journal of Infrared, Millimeter, and Terahertz Waves, 41, No. 1, pp 1–140 (2020) related to the development of gyro-devices (Tables 2–34). Emphasis is on high-power gyrotron oscillators for long-pulse or continuous wave (CW) operation and pulsed gyrotrons for many other applications. In addition, this work gives a short update on the present development status of frequency step-tunable and multi-fre-quency gyrotrons; coaxial-cavity multi-megawatt gyrotrons; complex two-section stepped cavity gyrotrons; gyrotrons for technological and spectroscopy applica-tions; relativistic gyrotrons; large orbit gyrotrons (LOGs); quasi-optical gyrotrons; fast- and slow-wave cyclotron autoresonance masers (CARMs); gyroklystron, gyro-TWT, and gyrotwystron amplifiers; gyro-harmonic converters; gyro-BWOs; and dielectric vacuum windows for such high-power mm-wave sources. Gyrotron oscil-lators (“gyromonotrons or just gyrotrons”) are mainly used as high-power millim-eter-wave sources for electron cyclotron heating (ECH), electron cyclotron current drive (ECCD), stability control, and diagnostics of magnetically confined plasmas for clean generation of energy by controlled thermonuclear fusion. Megawatt-class gyrotrons employ synthetic-diamond output windows and single-stage depressed collectors (SDCs) for electron energy recovery. The maximum pulse length of the 140 GHz, 1.3 MW IPP-KIT-THALES gyrotron is 3 min (1.2 MW/6 min) at 97.5% Gaussian output mode purity and 47% efficiency. The 1 MW version of this tube operates at pulse lengths up to 30 min, and PLL-frequency stabilization has been demonstrated. The first Japan QST-CANON 170 GHz ITER gyrotron prototype achieved 1 MW, 800 s at 55% efficiency and holds the energy world record of 2.88 GJ (0.8 MW, 60 min, 57%). The Russian 170 GHz ITER gyrotron obtained 0.99 (1.2) MW with a pulse duration of 1000 (100) s and 57 (53)% efficiency. First frequency-injection-locked operation of a very high-order-mode Russian 170 GHz-1 MW
gyrotron (IAP) has been demonstrated in short pulses using a PLL-frequency-sta-bilized 20 kW gyrotron master oscillator. A Russian short-pulse 74.2 GHz, 100 kW
gyrotron (SPbSTU) with 4-stage depressed collector achieved an efficiency of 72%.
The prototype tube of the KIT 2 MW, 170 GHz coaxial-cavity gyrotron (pulse dura-tion 50 ms) achieved in 1 ms pulses the record power of 2.2 MW at 48% efficiency
and 96% Gaussian mode purity and was operated at pulse lengths up to 50 ms. High-power CW gyrotron oscillators have also been successfully used in materials
processing. Such technological applications require tubes with the following param-eters: f ≥ 24 GHz, Pout = 4–50 kW, CW, η ≥ 30%. Gyrotrons with pulsed magnet for
various short-pulse applications deliver Pout = 210 kW with τ = 20 μs at frequencies up to 670 GHz (η ≅20%), Pout = 5.3 kW at 1 THz (η = 6.1%), and Pout = 0.5 kW at
1.3 THz (η = 0.6%). The average powers produced by 94 GHz gyroklystrons, gyrot-wystrons, and gyro-TWTs are 10 kW, 5 kW, and 20 kW, respectively
Mechanistic insights into the adverse effects of cisplatin employing the zebrafish model
No full textDer Einsatz von Cisplatin, einem weit verbreiteten Chemotherapeutikum, ist mit verschiedenen Nebenwirkungen und toxischen Reaktionen verbunden, darunter Nierentoxizität, Neurotoxizität und Ototoxizität, die seine klinische Anwendung einschränken. Eine dieser Nebenwirkungen, die Nierentoxizität, kann zu akutem Nierenversagen führen und stellt eine erhebliche Bedrohung für die Patientensicherheit dar. Das Verständnis der Mechanismen, die der cisplatininduzierten Nierentoxizität zugrunde liegen, ist entscheidend für die Entwicklung präventiver und therapeutischer Strategien zur Verringerung des Risikos einer Nierenschädigung während der klinischen Anwendung.
Um die potenziellen Regulationsmechanismen zu analysieren, wurde in dieser Studie zunächst ein Zebrafischlarvenmodell der durch Cisplatin induzierten Nephrotoxizität etabliert. Dies umfasste die Auswahl geeigneter Zeitpläne für die Injektion der Larven, die Verbesserung der Injektionstechniken und die Umsetzung von phänotypischen Scoring-Methoden. Innerhalb dieses Modells führte die funktionelle Hemmung des G-Protein-gekoppelten Östrogenrezeptors (GPER) effektiv zu einer Verringerung abnormer Phänotypen und einer Abnahme der Hochregulationeiniger Marker für Nierenschädigung, die durch Cisplatin verursacht wurden. Dies legt eine potenzielle regulierende Rolle von GPER in der durch Cisplatin induzierten Nephrotoxizität nahe. Weitere biochemische Analysen und Inhibitorexperimente zeigten, dass die Hemmung der GPER-Funktion zu einer Verringerung der Aktivierung von Mitogen-aktivierten Proteinkinasen (MAPK) führte, was darauf hindeutet, dass die GPER-MAPK-Kaskade für die durch Cisplatin induzierte Nephrotoxizität wichtig ist
Engaging Schools and Communities in Geothermal Monitoring Case Studies from the DeepStor Research Infrastructure
Get PDFSeismic Imaging and Monitoring with Distributed Acoustic Sensing on Dark Fibers at the KIT Campus
Get PDFSeismic monitoring is essential for the successful and sustainable exploration and operation of underground reservoirs and storage systems. Distributed Acoustic Sensing (DAS) has emerged as a solution for the acquisition of seismic data with high spatial density and extensive coverage, benefiting seismic monitoring efforts. Making use of unused telecommunication fibers, or dark fibers, is a particularly attractive opportunity due to the widespread availability of this infrastructure. It can help address the challenges associated with deploying and maintaining extensive seismic networks, particularly in urban areas targeted for geothermal energy development. This study uses a 3 km section of the telecommunication network at the Karlsruhe Institute of Technology (KIT) to conduct seismic monitoring near the planned DeepStor geothermal research infrastructure. The research includes a preliminary verification of the fiber\u27s location and reports observations from local seismic events, harnessing the high spatial density of sensing points for beamforming analysis. Additionally, a signal classification framework is designed to detect and categorize frequent vehicle passages. The analysis of the associated signals makes it possible to extract virtual shot gathers. These gathers facilitate the analysis of dispersion curves at relatively high frequencies, which are subsequently used to invert shear-wave velocity profiles. This complements lower-frequency analyses derived from microseism signals during periods of minimal anthropogenic activity. Continuous seismic wavefield recordings were collected over an eight-month period, providing access to a significant time series for analysis of temporal variations and signal stacking. Our results provide a basis for future seismic monitoring of the upcoming DeepStor research infrastructure on the KIT Campus North. They also demonstrate the potential of ambient seismic wavefield analysis for advanced subsurface characterization and contribute to the broader application of DAS technology in urban seismic monitoring
A Mg²⁺-Regulated Hydrated Vanadium Oxide Positive Electrode for Aqueous Mg-Ion Batteries
Get PDFAqueous Mg-ion batteries (AMIBs) have emerged as promising candidates for grid-level energy storage systems, thanks to their exceptional safety characteristics, cost-effectiveness, and abundant Mg resources. However, AMIBs confront great challenges, such as the shortage of high-performance electrodes and the sluggish Mg2+ diffusion in the electrodes. In this work, a Mg2+-regulated bilayered vanadium oxide (MgVOnH) positive electrode, holding a large interplanar spacing of ∼13.4 Å, was investigated in 0.8 m Mg(TFSI)2–85% poly(ethylene glycol) (PEG)–15% H2O and 0.8 m Mg(TFSI)2–65% PEG–20% dimethyl sulfoxide (DMSO)–15% H2O (20% DMSO-containing) electrolytes. MgVOnH delivers a first discharge capacity of 268 mAh g–1 at 50 mA g–1, obtaining 81% capacity retention after 100 cycles (against a second discharge capacity of 249 mAh g–1) in a DMSO-free electrolyte, whereas MgVOnH exhibits much better rate capability and high capacity at 500 and 1000 mA g–1 in the DMSO-containing electrolyte, respectively. Particularly, MgVOnH shows a first discharge capacity of 106 mAh g–1 at 1000 mA g–1, maintaining 80/65% of its capacity after 920/2000 cycles. Furthermore, the electrochemical reaction mechanism and reversibility of MgVOnH during Mg2+ (de)intercalation are systematically explored through ex situ techniques. This work helps us to understand the mechanisms, and this can guide us in achieving a better design for high-performance positive electrodes for AMIBs
Efficient accelerator operation with artificial intelligence based optimization methods
Get PDFPoster of IPAC´25 conference: Tuning injectors is a challenging task for the operation of accelerator facilities and synchrotron light sources, particularly during the commissioning phase. Efficient tuning of the transfer line is essential for ensuring optimal beam transport and injection efficiency. This process is further complicated by challenges such as beam misalignment in quadrupole magnets, which can degrade beam quality and disrupt operations. Traditional tuning methods are often time-consuming and insufficient for addressing the complexities of high-dimensional parameter spaces. In this work, we explore the use of advanced AI methods, including Bayesian optimization, to automate and improve the tuning process. Initial results, demonstrated on the transfer line of KARA (Karlsruhe Research Accelerator) at KIT (Karlsruhe Institute of Technology), show promising improvements in beam alignment and transport efficiency, representing first steps toward more efficient and reliable accelerator operation. This study is part of the RF2.0 project, funded by the Horizon Europe program of the European Commission, which focuses on advancing energy-efficient solutions for particle accelerators
