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Radiological Safety Evaluation of the Processing Facility of the Spent Resin Mixture Generated in the Heavy Water Reactor
No full textUltrafast and on-demand oil/water separation with vertically aligned cellulosic smart sponge
No full textSlow oil sorption speed of commercial non-woven polypropylene (PP) sorbent remains a major challenge for efficient clean-up of oil spillage. Adsorption-based polymeric sponge oil removing offers an appealing way to solve this challenge by increasing surface area. However, the tortuous oil sorption path and plastic waste after oil uptake are two long-standing bottlenecks for realizing efficient oil spill removal. Here, we report a vertically aligned-biomass fiber junctioned sorbents (a-BFJS), by confining delignified biomass with carbon nanotube (CNT), polyvinyl alcohol (PVA), and methyltrimethoxysilane (MTMS). The sorbent shows an excellent perfor-mance towards xylene sorption capacity with uptake about 50 g g-1 within 10 s. This is due to the wide and short pathway of their aligned channels, which improves the capillary effect and fast oil transport in the oriented channels. Moreover, the sponge exhibits fast oil sorption-desorption kinetics enabled by simple mechanical squeezing. We further engineered a scalable rapid continuous oil skimming with simple peristaltic pump. The oil recovering using a-BFJS realized high oil selectivity from xylene/water emulsion. Our demonstration of the high-performance aligned channel sorbent and scalable oil removing sponge offers an eco-friendly and promising strategy for efficiently removing oil from oil spills from water
Intensified Nonequilibrium Effect of Polymer Nanocomposites with Decreasing Nanoparticle Size
No full textWhat are the most important and decisive parameters that determine the structure and the property of polymer nano composites (PNCs)? Previous studies answered that controlling the nanoparticle interface is critical, which can be achieved with a choice of a compatible nanoparticle, a proper surface modification, and a change in the polymer chain length. In addition to these parameters, the processing condition of PNCs has recently emerged as an influential parameter for controlling PNC properties, suggesting the existence of the nonequilibrium effect of PNCs. In this regard, we chose the solvent as a main change in the processing condition and investigated the initial solvent-driven nonequilibrium effect of PNCs with varied nanoparticle (NP) sizes. We found that the type of the initial solvent is indeed crucial in determining the ultimate properties of the PNCs, and this becomes more influential as the size of NPs decreases. The decreasing size of NPs causes a conformational change in the adsorbed polymers from tightly packed layers to loosely dangling chains. This results in much greater differences in NP microstructures and rheological properties of PNCs, indicating a stronger nonequilibrium effect with smaller NPs
A Behind-The-Ear Patch-Type Mental Healthcare Integrated Interface with 275-Fold Input Impedance Boosting and Adaptive Multimodal Compensation Capabilities
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Brane Brick Models for the Sasaki-Einstein 7-Manifolds Y^{p,k}(CP^1 x CP^1) and Y^{p,k}(CP^2)
No full textThe 2d (0, 2) supersymmetric gauge theories corresponding to the classes of Yp,k(??????1 ?? ??????1) and Yp,k(??????2) manifolds are identified. The complex cones over these Sasaki-Einstein 7-manifolds are non-compact toric Calabi-Yau 4-folds. These infinite families of geometries are the largest ones for Sasaki-Einstein 7-manifolds whose metrics, toric diagrams, and volume functions are known explicitly. This work therefore presents the largest list of 2d (0, 2) supersymmetric gauge theories corresponding to Calabi-Yau 4-folds with known metrics
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No full textCrystal Facet and Electronic Structure Modulation of Perovskite Oxides for Water Oxidation
No full textIn water-splitting catalysts, exposing high-activity crystal facets with optimal electronic structures can significantly enhance the oxygen evolution reaction (OER) kinetics. In this work, we demonstrate a facile strategy for simultaneously modulating the preferential crystal facet and electronic structure of perovskite oxides for their use as water-electrolysis catalysts using a template-mediated growth approach. Experimental and computational analyses revealed that the preferred crystal facet of La0.5Sr0.5CoO3 (LSC) grown on MoReS2 was effectively modulated to the (110) plane, and the free energy barrier of the rate-determining step was lowered by such crystal facet engineering. Furthermore, the interfacial charge transfer between LSC and MoReS2 enabled the optimal electronic structure of the B-site cation in LSC. Consequently, LSC grown on MoReS2 exhibited an OER activity of 210 mV at 10 mA cm???2, surpassing the performance of state-of-the-art perovskite oxide-based catalysts. Our findings provide new insights into the design of efficient perovskite oxide-based electrocatalysts for water electrolysis
A Simulation Study of Ultra-relativistic Jets. III. Particle Acceleration in FR-II Jets
No full textWe study the acceleration of ultra-high-energy cosmic rays (UHECRs) in Class II Fanaroff-Riley (FR-II) radio galaxies by performing Monte Carlo simulations for the transport, scattering, and energy change of CR particles injected into time-evolving jet flows that are realized through relativistic hydrodynamic simulations. Toward that end, we adopt physically motivated models for the magnetic field and particle scattering. By identifying the primary acceleration process among diffusive shock acceleration (DSA), turbulent shear acceleration (TSA), and relativistic shear acceleration (RSA), we find that CRs of E? 1 EeV gain energy mainly through DSA in the jet-spine flow and backflow containing many shocks and turbulence. After they attain E ? a few exaelectronvolts, CRs are energized mostly via RSA at the jet-backflow interface, reaching energies well above 10(20) eV. TSA makes a relatively minor contribution. The time-asymptotic energy spectrum of escaping particles is primarily governed by the jet power, shifting to higher energies at more powerful jets. The UHECR spectrum fits well to a double power-law form, whose break energy, E (break), corresponds to the size-limited maximum energy. It is close to dN/dE infinity E-0.5 E (break), while it follows dN/dE infinity E-2.6 E (break), decreasing more gradually than the exponential. The power-law slope of the high-energy end is determined by energy boosts via non-gradual shear acceleration across the jet-backflow interface and confinement by an elongated cocoon. We conclude that giant radio galaxies could be major contributors to the observed UHECRs
Building-up an interrelationship between isomeric benzyl inner side chains within nonfullerene acceptors and isomeric xylene solvents for non-chlorinated solvent-processed organic solar cells
No full textThe side-chain engineering of A-DA'D-A-type nonfullerene acceptors (NFAs), well known as the Y6 series, is an efficient approach for retaining the physical properties of the Y6 series but allowing the manipulation of the solubility, crystallization, intermolecular packing, and orientation. This can permit further fine-tuning of their structures for high power conversion efficiencies (PCEs) of organic solar cells (OSCs). Inspired by recent results regarding the critical roles of "inner side-chain modulation " in the aforementioned features, this study designed and synthesized three isomeric BzY-series NFAs (o-BzY, m-BzY, and p-BzY) using o-, m-, and p-hexylbenzyl side chains on the pyrrole motif of the Y6 core framework. This design concept implants a benzene ring at the branching position of the inner side chain. The interrelationship of the isomeric inner side chains within the BzY-series NFAs and isomeric xylene solvents (o-, m-, and p-xylenes) was examined by UV-vis spectroscopy, 1D/2D-nuclear magnetic resonance spectroscopy, and morphological characterization. In-depth studies of 3 (BzY-series NFAs) x 3 (solvents) pair systems of non-chlorinated solvent-processed OSCs found that the best PCEs were achieved from the additive and thermal annealing-free OSCs fabricated with the same structural isomeric pairs of BzY-series NFAs and solvents (i.e., o-BzY with o-xylene, m-BzY with m-xylene, and p-BzY with p-xylene cases). These findings show that the high structural compatibility between the side chains and processing solvents has great potential for improving the OSC performance
First-time comparison between NO2 vertical columns from GEMS and Pandora measurements
No full textThe Geostationary Environmental Monitoring Spectrometer (GEMS) is a UV???visible spectrometer onboard the GEO-KOMPSAT-2B satellite launched into geostationary orbit in February 2020. To evaluate GEMS NO2 column data, comparison was carried out using NO2 vertical column density (VCD) measured using direct-sunlight observations by the Pandora spectrometer system at four sites in Seosan, South Korea, during November 2020 to January 2021. Correlation coefficients between GEMS and Pandora NO2 data at four sites ranged from 0.35 to 0.48, with root mean square errors (RMSEs) from 4.7 ?? 1015 molec. cm-2 to 5.5 ?? 1015 molec. cm-2 for cloud fraction (CF) < 0.7. Higher correlation coefficients of 0.62???0.78 with lower RMSEs from 3.3 ?? 1015 molec. cm-2 to 4.3 ?? 1015 molec. cm-2 were found with CF < 0.3, indicating the higher sensitivity of GEMS to atmospheric NO2 in less-cloudy conditions. Overall, GEMS NO2 column data tend to be lower than those of Pandora due to differences in representative spatial coverage, with a large negative bias under high-CF conditions. With correction for horizontal representativeness in Pandora measurement coverage, the correlation coefficients range from 0.69 to 0.81 with RMSEs from 3.2 ?? 1015 molec. cm-2 to 4.9 ?? 1015 molec. cm-2 were achieved for CF < 0.3, showing the better correlation with the correction than that without the correction