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Long Functional Graft Polymer Induced Multiscale Morphological Inversion and Enhanced Anion Transport Efficiency in Radiation-Grafted Anion Exchange Membranes
No full textExploring compartmentalized jet polymerization for novel rod-shaped microgels and their potential in tissue engineering applications
No full textThis is MATE: A Multiple scAttering correcTion rEtrieval algorithm for accurate lidar profiling of seawater optical properties
No full textLidar has the capability to measure seawater vertical optical properties efficiently both day-time and night-time, though accurate retrieval is still challenging due to multiple scattering. Herein, we propose a Multiple scAttering correcTion and rEtrieval (MATE) algorithm suitable for shipborne, airborne and spaceborne lidars. The MATE algorithm provides the synchronous depth-resolved absorption, backscattering and diffuse attenuation co-efficients of seawater. A good consistency was obtained between retrieved results and the in situ data with a root mean square relative difference (RSMRD) of 6.36% for diffuse attenuation coefficient, corresponding to an improvement of 2 times over methods that neglect multiple scattering. These results indicate that the MATE algorithm has valuable application potential in the quantitative evaluation of marine biological parameters
Evaluation of tungsten as diffusion barrier for high-density U-Mo fuel using heavy-ion irradiation
No full textMonolithic plate-type nuclear fuels for research reactors based on a U-Mo alloy require a coating barrier between the fuel zone and the Al-based cladding to suppress the growth of the undesired interaction layer. The effectiveness of tungsten - an alternative to the commonly used zirconium - is studied to this end. Physical vapor deposition (PVD) serves as a suitable method to produce the required barrier layers. These W coatings turn out brittle, especially when combined with a subsequent cladding application, but show promising behavior in limiting thermal diffusion. This is confirmed in heavy-ion irradiation experiments to simulate in-pile performance of the fuel system. Irradiation of the W barrier from the direction of the Al cladding as well as from the U-Mo side displays mainly interaction of W and Al. As observed, a layer of 1 µm W is sufficient to prevent interaction of U-Mo and Al up to fission density equivalents of 7.5·10^20 fissions/cm³. The temperature effect dominates the growth of interaction layer when the sample temperature is increased from 140 °C to 200 °C
T aillefer —A Tool for Sensitivity Analysis and Uncertainty Propagation Studies for Steady-State Thermal-Hydraulic Simulations of Involute Fuel Element Research Reactors
No full textTaillefer is a versatile Python tool for carrying out Sensitivity Analysis (SA) and uncertainty propagation (UP) studies based on Monte Carlo sampling. Developed with the primary goal of investigating sensitivities and uncertainties of steady-state thermal-hydraulic (SSTH) safety parameters of the high-performance research reactors Forschungs Neutronenquelle Heinz Maier-Leibnitz (FRM II) in Garching, Germany, and the Réacteur à Haut Flux (RHF) in Grenoble, France, it can also be used for a large variety of other modeling problems.The work presented here aims to explain the underlying mathematical background of SA and UP studies with Taillefer and to show some steps to verify these routines. Furthermore, a real-life application example is provided that demonstrates Taillefer’s use in SSTH analysis of the RHF. For this purpose, Taillefer is coupled to the external thermal-hydraulic software PLTEMP/ANL, which is one of the codes used at FRM II and RHF to access SSTH performance and safety parameters.Determining these crucial quantities is part of identifying possible low-enriched uranium (LEU) core designs that are suitable to replace the currently used highly enriched uranium fuels of the two reactors, supporting global nonproliferation efforts. Taillefer is a powerful tool in these conversion studies, as it increases the reliability of the LEU safety parameters by providing information about sensitivities and uncertainties in addition to the nominal values predicted by the thermal-hydraulic software
Deploying a C++ Software with (or without) Python Embedding and Extension
No full textWe discuss the manifold difficulties in cross-platform software deployment. We first consider a pure C++ project. Then we discuss the additional problems that arise when a C++ core has an embedded Python interpreter and is exposed to Python with bindings automatically generated by Swig. We explain how such a software can be deployed to Windows, Linux, and macOS, in form of source archives, binary installers, packages for package managers, or Python wheels. Our solutions are based on proven experience with the physics software BornAgain
Effects of Functional Graft Polymers on Phase Separation and Ion-Channel Structures in Anion Exchange Membranes Analyzed by SANS Partial Scattering Function
No full textSolvation Dynamics of Thermoresponsive Polymer Films: The Influence of Salt Series in Water and Mixed Water/Methanol Atmosphere
No full textUnderstanding the salt effects on solvation behaviors of thermoresponsive polymers is crucial for designing and optimizing responsive systems suitable for diverse environments. In this work, the effect of potassium salts (CH 3 COOK, KCl, KBr, KI, and KNO3 ) on solvation dynamics of poly(4-(N- (3’-methacrylamidopropyl)-N,N-dimethylammonio) butane-1-sulfonate) (PSBP), poly(N-isopropylmethacrylamide) (PNIPMAM), and PSBP-b- PNIPMAM films is investigated under saturated water and mixed water/methanol vapor via advanced in situ neutron/optical characterization techniques. These findings reveal that potassium salts enhance the films’ hygroscopicity or methanol-induced swellability. Interestingly, the anions effects do not mirror the empirical Hofmeister series, which describes the salting-in effects for such polymers in dilute aqueous solution, particularly evident in PSBP films with an approximately inverted order. PNIPMAM and PSBP-b-PNIPMAM exhibit pronounced deviations from such an inverted correlation and vary somewhat for water-rich and methanol-rich atmospheres. Molecular dynamics (MD) simulations suggest that the observed orders of solvation result from the accessibility of the hydrated solvation shells close to the PSBP-b-PNIPMAM chains