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Analysis and modelling of Inner Fuel Cycle performance using exhaust bypass and Direct Internal Recycling
No full textFusion power plants require robust fuel cycle (FC) architectures that minimize tritium inventories while managing impurity build-up and isotopic imbalances. This work investigates the performance of a Inner Fuel Cycle (IFC) architecture based on the Direct Internal Recycling (DIR) concept, with an additional bypass loop for recycling of exhaust gases utilized in gas puffing. Particular focus is given to fuel dilution due to impurity accumulation and deuterium–tritium (D–T) imbalance. A new Julia-based dynamic fuel cycle modeller, MINERVA (Modelling and Integration of Nuclear fusion Energy Reactor fuel cycle for Versatile Analysis), is introduces and used to evaluate the performances of the proposed architecture and for understanding the dynamics and criticalities of a DIR-based FC. Protium build-up is identified as a potential challenge, with accumulation becoming problematic at high separation efficiencies without dedicated removal systems. Two reactor case studies are analysed, EU DEMO 2018 and Gauss Fusion’s GIGA reactor. Results demonstrate that the proposed architecture effectively manages impurity concentrations below 1% for protium while maintaining optimal D–T ratios through active control systems. The proposed architecture achieves significant reductions in external fuel requirements, with effective conversion ratios growing exponentially with DIR separation efficiency. The bypass loop successfully provides the majority of gas puffing requirements without causing excessive impurity accumulation. This work establishes a foundation for advanced fuel cycle optimization studies essential for the development of commercial fusion power plants
Update of the integrated flight simulator for ASDEX Upgrade
No full textWe present the latest updates of the flight simulator of ASDEX Upgrade (AUG),
‘Fenix AUG’. Fenix AUG contains simplified models for both the plasma physics and the device operation. The updated version is split into three independent repositories and has been integrated into Docker containers for better management and deployment. The device models can now directly import their configuration from the AUG control system. Although the physics models can be fine tuned to each case, the default settings have been set up to run a large variety of experiments without the need of case-to-case adaptation. Together, the enhancements make Fenix AUG a versatile tool that can be applied to a wide range of applications ‘out-of-the-box’, such as: to compare simple physics models to the experiment, to assess new controllers within the framework of the existing ones, or, to verify that a planned discharge will follow expected trajectories and will not run into machine or safety limits. An example of each application is showcased to highlight some strengths and limitations of the simulator
No HDL, No Problem: HLS-Generated Power Wasters for Fault Injection in Cloud FPGAs
No full textPower wasters are a critical threat to cloud FPGAs. They induce voltage drops that lead to timing faults or complete denial of service. Previous methods for generating power wasters rely on low-level RTL modifications, including primitive-level structures and constraint manipulation. However, newer FPGA platforms such as Xilinx Versal restrict access to such low-level features, preventing traditional attack methods. In this work, we are the first to show that power wasters can still be created using only High-Level Synthesis (HLS), which is a standard development flow for cloud FPGAs. We demonstrate HLS-generated power wasters that can inject faults or crash the FPGA by applying overclocking and selected input patterns
Tailoring K/Vacancy Disordered Layered Oxide via Charge Engineering for Stabilizing High‐Performance Potassium‐Ion Batteries
No full textLayered transition metal oxides represent attractive cathode candidates for potassium-ion batteries (PIBs), due to their high theoretical specific capacity. However, sluggish K diffusion and structural instability, stemming from the inherent K/vacancy ordered structure, lead to poor rate performance and cycling stability. Herein, a charge-ion coupling engineering strategy, wherein transition-metal electronic structure is tuned to modulate interlayer K/vacancy configurations, is initially pioneered. Specifically, a K/vacancy-disordered P3-type structure is constructed via targeted transition metal (TM) doping in Mn/Co-based layered oxides. Exploiting the identical valence of Ti and Mn coupled with their divergent redox potential, the doping sites suppress charge ordering within TM slabs through modulating charge delocalization, thereby inducing interlayer K/vacancy disordering. The K/vacancy disordered KMnCoTiO delivers long-term stability with 58.6 mAh g over 800 cycles at 1 A g and remarkable rate capability of 61.7 mAh g at 2 A g, facilitating a highly reversible single-phase solid-solution reaction in KMnCoTiO and enhancing the structural stability during K extraction/insertion. Meanwhile, molecular dynamics simulations demonstrate that the K/vacancy disordered structure contains interconnected channels enabling continuous and rapid K diffusion. This work establishes a cation substitution strategy for manipulating K/vacancy order-disorder to develop high-performance, kinetically robust cathode materials for next-generation PIBs
Microlensing of nonsingular black holes at finite size: A ray tracing approach
No full textWe study the gravitational microlensing of various static and spherically symmetric nonsingular black holes (and horizonless, nonsingular compact objects of similar size). For pointlike sources we extend the parametrized post-Newtonian lensing framework to fourth order, whereas for extended sources we develop a ray tracing approach via a simple radiative transfer model. Modelling nonrelativistic proper motion of the lens in front of a background star we record the apparent brightness as a function of time, resulting in a photometric lightcurve. Taking the star radius to smaller values, our numerical results approach the theoretical predictions for pointlike sources. Compared to the Schwarzschild metric in an otherwise unmodified lensing geometry, we find that nonsingular black hole models (and their horizonless, nonsingular counterparts) both at finite size and for point lenses tend to feature larger magnifications in microlensing lightcurves
Effect of Silylene Ligand on Catalytic Pathway of Alkene Hydrosilylation Catalyzed by Phosphine Cobalt(III) Hydrides
No full textIn this paper, two cobalt(III) hydrides, [(PMe)Co(H)(Cl)(SiHPh)] (3) and [(LSi:)(PMe)Co(H)(Cl)(SiHPh)] (LSi: = {PhC (NBu)}SiCl) (4), were used as catalysts to compare their catalytic performance on the hydrosilylation of alkenes. The research results indicate that both cobalt(III) complexes 3 and 4 are good catalysts for the hydrosilylation of alkenes, affording Markovnikov products for aryl alkenes and anti-Markovnikov products for alkyl alkenes. It was found that the catalytic activity of phosphine cobalt(III) hydride 3 is higher than that of silylene cobalt(III) hydride 4 for aryl alkenes. On the contrary, the catalytic activity of silylene cobalt hydride 4 is better than that of phosphine cobalt hydride 3 for alkyl alkenes. Different experiments were designed to study the catalytic mechanism for hydrosilylation of alkenes catalyzed by complexes 3 and 4. We found that complex 3 first reacted with PhSiH when it was used as a catalyst. From the stoichiometric reaction between complex 3 with PhSiH we obtained the known complex 5 [(PhClSi)Co(H)(PMe)]. Further experiment indicates that hydrido cobalt(I) intermediate 5b, [HCo (PMe)], is an active intermediate in the hydrosilylation of alkenes catalyzed by complex 3. When silylene cobalt(III) hydride 4 was used as a catalyst, complex 4 reacted at first with styrene, and four-coordinated bis (silylene) cobalt(I) chloride Co (LSi:)(PMe)Cl was proposed as the active intermediate in the hydrosilylation of alkenes. Based on the experimental results, two different possible catalytic mechanisms catalyzed by complexes 3 and 4 were proposed, respectively
Effects of Allulose vs Aspartame Consumption on Postprandial Glucagon-Like Peptide-1 Profiles and Metabolic Health: Protocol for a Randomized, Crossover, Double-Blind, Placebo-Controlled Trial
No full textBackground: Excessive sugar consumption is a public health concern. Allulose, a low-calorie sugar with similar functional properties to sucrose, offers potential metabolic benefits. Animal and limited human studies suggest it may stimulate glucagon-like peptide-1 (GLP-1) secretion, improve glucose regulation, and support weight management. However, evidence to substantiate these effects in humans remains scarce.
Objective: The primary aim of this study, the low-calorie sweetener intervention study allulose (LisA), was to assess differences in the postprandial GLP-1 profile (primary outcome) between an acute intake of allulose and aspartame interventions in healthy adults. Secondary goals included exploratively assessing potential subacute adaptation effects over a 4-week consumption period and evaluating a comprehensive set of parameters as hypothesis-generating findings for future large-scale research.
Methods: We conducted a randomized, double-blind, placebo-controlled, crossover trial in healthy adults. Participants daily consumed either 3 allulose-sweetened or aspartame-sweetened beverages for 4 weeks in crossover, with a washout in between. Standardized inpatient procedures were conducted at the study baseline and at the beginning and end of each intervention phase. The primary outcome is the postprandial profile of GLP-1. Secondary outcomes include further parameters of gut hormone secretion, insulin sensitivity (Matsuda Index), body composition (body impedance analysis), subjective satiety (visual analog scales), and gastrointestinal tolerance. We also assess multiomic endpoints, including sugaromics and gut microbiome composition. The primary outcome will be analyzed using the incremental area under the curve with a 2-tailed paired t test. All further outcomes (including peak and total area under the curve for GLP-1) will be assessed using linear mixed models.
Results: A total of 10 participants (4 female and 6 male; mean age 31.2, SD 6.8 years; BMI 25.1, SD 2.6 kg/m2) completed all study procedures. The sample collection phase was successfully concluded in November 2023. Data processing and statistical analysis for the primary outcome are expected to be completed by June 2026.
Conclusions: The comprehensive study protocol, integrating a rigorous crossover design with multiomic analysis, is poised to provide confirmatory evidence for the acute GLP-1 effects of allulose and generate valuable mechanistic hypotheses regarding its subacute metabolic and gut health effects. The findings will contribute to the evidence base required for evaluating allulose\u27s potential role in public health sugar reduction strategies.
Trial registration: German Clinical Trials Register DRKS00028521; https://drks.de/search/en/trial/DRKS00028521.
International registered report identifier (irrid): DERR1-10.2196/81857
Konzeptstudie zur Entwicklung einer skalierbaren Infrastruktur für Kerosin-Fraktionen unter Berücksichtigung geographischer und technischer Rahmenbedingungen
No full textZiele der Studie
• Entwicklung tragfähiger Logistikkonzepte für Lagerung, Blending und Verteilung von Sustainable Aviation Fuel (SAF).
• Sicherstellung von Skalierbarkeit (Basisfall 40 kta SAF → 200 kta bis 2050).
• Integration regulatorischer Anforderungen (RED III, CORSIA, ReFuelEU Aviation).
• Qualitätssicherung & Nachhaltigkeit: Einhaltung physikalisch-chemischer Standards (ASTM) und Zertifizierungssysteme (ISCC, RSB)
Self Dilution of Model Polystyrene Pom‐Poms and Combs by Unentangled Side Arms
No full textWe present linear-viscoelastic characterization and elongational viscosity start-up data of 4 model polystyrene pom-poms and 2 model polystyrene combs. All 6 model systems have a self-entangled backbone, but unentangled side arms. Pom-poms consist of a linear backbone with one branching point with q arms at each end of the backbone. Analysis by the Enhanced Relaxation of Stretch (ERS) model shows that the elongational rheology of all model polymers is equivalent to that of polymer melts consisting of long linear chains diluted by short, unentangled linear polymer chains of the same chemistry. Strain hardening increases with
increasing intrinsic dilution of the backbone by the arms. The comparison of the elongational viscosity data of pom-poms versus that of the combs with several branching points along the backbone chain suggests that the location of the unentangled side arms does not result in significant differences. At higher elongation rates, brittle filament fracture is observed, which is well described by the fracture criterion for linear melts and polymer solutions, thus confirming the self-dilution of the backbone chains of pom-poms and combs by unentangled side arms