Size-induced H-adsorption self-optimization of Au cocatalysts for robust photocatalytic H2 production.

The efficient treatment of uranium-contaminated water bodies is a challenge for the sustainable development of nuclear energy. Therefore, we developed a novel composite membrane (V-SnS2/rGO) comprising an interconnected sulfur-vacancy SnS2 scaffold encapsulated within cross-linked reduced graphene oxide. This unique structural design imparts the V-SnS2/rGO membrane with strong absorption across the entire solar spectrum. Moreover, the photothermal conversion capability of rGO, combined with its rapid heat transfer to the V-SnS2 catalyst, synergistically accelerates catalytic reaction kinetics. The optimized V-SnS2/rGO-2 membrane achieves a U(VI) removal efficiency exceeding 79.1% within 1 h under full-spectrum irradiation, a performance that surpasses that of most reported catalysts. The reaction rate constant reached 0.099 min-1 without any sacrificial agents in air, representing a 2.25-fold increase compared to V-SnS2. The presence of sulfur vacancies induced the formation of asymmetric S-O units at the V-SnS2/rGO interface, generating a polarized built-in electric field that efficiently promotes charge separation and transfer. Consequently, the increased electron density on the surface of V-SnS2/rGO-2 facilitates oxygen molecule activation and the formation of superoxide radicals, enhancing H2O2 generation and ultimately converting U(VI) into insoluble (UO2)O2·2H2O. This work provides a strategic approach to designing photothermal catalytic membranes through defect engineering and interfacial bond modulation.

Abstract A promising approach to handle the intense plasma heat flux in the divertor region of a tokamak is the Vapour Box Divertor (VBD). Here plasma-lithium interaction creates a dense lithium vapour cloud which interacts with the incoming plasma, effectively shielding the tungsten surface beneath, therefore preventing overheating and sputtering of the tungsten and increasing the component's lifetime. Two key steps must be addressed to validate this concept: investigating plasma-Li interactions and the transport mechanism of the latter in the presence of plasma. To explore this, a Vapour Box Module (VBM) has been designed for use with the linear plasma generator Magnum-PSI. The VBM consists of a series of three cylindrical boxes, with Li being evaporated at a controlled temperature in the central box. Divertor-like plasma enters the VBM from an upstream aperture, interacts with the Li vapour cloud and exits through a downstream aperture ultimately impacting a target equipped with a calorimetry system. Optical diagnostics Thomson scattering, Filtered fast camera Imaging and Optical Emission Spectroscopy provided information on plasma parameters in terms of electron density n e , temperature T e and plasma composition before and after this interaction. A significant reduction in plasma power was observed upon the establishment of lithium vaporization determined via cooling water calorimetry and embedded thermocouples at the downstream target. This resulted in a drop of the target temperature from ~ 800 °C to ~ 350 °C (57%) at the highest applied power (11.1 MW m -2 ) and central box temperature ~ 700 °C). Lithium condensation at the side boxes of the VBM in combination with strong plasma momentum transfer effectively prevented upstream migration of lithium, while enhancing Li transport toward the target. The achievement of the two main goals of reducing plasma power and confining the Li in the VBM, are consistent with earlier published preliminary SOLPS-ITER simulations. This study shows that the presence of lithium in a vapour box divertor-like configuration can result in a strong reduction of power to the target surface, while at the same time the lithium vapour is effectively confined by the VBM, aided by the incoming plasma, preventing its escape from the VBM geometry. This represents a valuable step toward validating the feasibility of the VBD configuration in future fusion reactors.

Abstract This study investigates the optical properties of nine indium gallium zinc oxide (IGZO) thin films deposited under three oxygen partial pressures (OPP) (10, 30, 50%) and three working pressures (2, 5, 10 mTorr). Spectroscopic ellipsometry (SE) data were analyzed with the Cauchy–Urbach (CU) model to extract refractive index (n), extinction coefficient (k), and dielectric functions (ε₁, ε₂). Thicknesses derived from SE agreed with stylus profiler measurements within 10%, confirming the CU model’s reliability. Both n and k decreased with increasing working pressure, reflecting reduced electron density due to fewer oxygen vacancies. While n varied <1% at 623 nm across the OPP range, k and ε₂ were highly sensitive to oxygen incorporation, decreasing by ~54% at 623 nm as OPP increased from 10% to 50%. These results indicate that higher OPP and working pressures suppress oxygen-vacancy–induced sub-gap states, thereby lowering optical absorption in the visible range.

Structural basis of hydride and proton transfer reactions revealed by the detection of hydrogen atoms in mammalian NADH-cytochrome b5 reductase.

We present the first molecular dynamics simulation of a hepatitis B virus (HBV) particle, encompassing both the icosahedral capsid and the surrounding lipid-protein envelope. Using a chemically realistic coarse-grained model with the SPICA force field, we simulated HBV envelope systems with and without the capsid alongside a pure lipid vesicle for comparison. Our simulations accurately reproduce experimental electron density profiles and reveal stable molecular interactions between capsid spikes and transmembrane regions of S proteins. These interactions involve experimentally validated contact sites as well as previously unrecognized residues that are critical for envelope-capsid association. We also found that lipid diffusion within the envelope is more than five times slower than in a simple vesicle and is further reduced by the presence of the capsid. This highlights the strong protein-mediated modulation of the membrane dynamics. This study provides the first molecular-level view of the HBV capsid-envelope complex and establishes a foundation for more complete HBV models that will include M/L proteins, nucleic acids, and diverse lipid components.

Abstract Plasma state reconstruction methods combining measurements and physics modeling improve the estimation of physics quantities in real-time and in post-discharge analysis. We present a workflow to reconstruct the dynamic evolution of a set of internal tokamak plasma profiles with consistent equilibria, as applied in this paper for experimental data from TCV L and H-mode discharges. 
Plasma profile estimates for electron temperature T e , electron density n e and parallel current density j par are obtained by data assimilation of Thomson scattering (TS) measurements into RAPTOR modeling, using an Extended Kalman Filter (EKF). A new kinetic equilibrium reconstruction method ensures mutual consistency of free-boundary equilibrium reconstruction, core plasma profile estimates and mapping of the TS measurements to flux surface coordinates. The RAPTOR code captures the coupled dynamics of electron heat, particle and current density transport and includes a model for the onset conditions of sawtooth instabilities and the resulting profile relaxations after a sawtooth crash, enabling a realistic q profile reconstruction even in the absence of direct measurements. During phases with sawtooth instabilities, the sawtooth period and inversion radius inferred from soft X-ray measurements are in excellent agreement with RAPTOR EKF inner q profile reconstructions and the predicted sawtooth dynamics, even for transient phases. 
In addition to the plasma profiles, the EKF allows to infer unknown physics quantities such as the effective charge Z eff and the on-axis ion-to-electron temperature ratio T i0 /T e0 , as well as transport model parameters. Continuously updating the transport model parameters for electron heat and density transport, based on the available measurements, is an effective way to reduce the model-to-reality gap, as required for real-time model-based control of fusion reactor plasmas.

Structural and electronic effects of M- and X-site substitution in M4Ag2BiX9 (M = Cs, Rb; X = Br, I) layered Zintl halides.

Investigating the influence of solvent molecular structure on the separation of α-olefins in Fischer-Tropsch naphtha.

A comprehensive laser-induced plasma diagnostics of hafnium using fundamental and second harmonics of pulsed Nd: YAG laser.

The gamma and neutron shielding performance of CeO2 and Er2O3 doped Al2Si2O5(OH)4-KAlSi3O8-SiO2 ceramics.

Validation and optimization of dual-energy CT for accurate dose calculation in photon radiotherapy of brain metastases.

Ultrastructural investigation of pellicle modification by statherin-derived peptide associated with epigallocatechin-3-gallate to prevent dental erosion: In situ proof-of-concept.

Understanding the nature of the interaction between the lead(II) ion, Pb2+, and water molecules is crucial to describe the stability and chemical behaviour of structures formed during solvation, as well as the conditions that favour the coordination or hydrolysis of Pb2+. In this work, we studied relativistic effects in the solvation process of Pb2+ using the zeroth-order regular approximation (ZORA) Hamiltonian at both scalar (SR-ZORA) and spin-orbit (SO-ZORA) levels. We analysed the potential energy surface of the lead ion coordinated with up to eight water molecules in order to identify the motifs that can be characterized as true minima. We applied several methodologies for studying the energies and interactions of the clusters, such as energy decomposition analysis (EDA), molecular orbital analysis, quantum theory of atoms in molecules (QTAIM) analysis, and natural bond orbital (NBO) analysis. The inclusion of relativity at a higher level (spin-orbit) is mandatory for solvation and binding energy calculations, changing the energetic ordering of the [Pb(H2O)n]2+ clusters. We found that at least two water molecules are needed to initiate deprotonation and form the OH- and H3O+ pair, thereby starting the hydrolysis by Pb2+. In addition, we examined the influence of the 6s2 inert pair in the formation of holodirected and hemidirected clusters. According to the geometric parameters, the stereochemistry of the [Pb(H2O)2-8]2+ clusters is mainly influenced by the relativistic effects stabilising the 6s2 lone pair of the lead ion, removing it from the HOMO, which reduces its stereochemical activity.

Here, we report the X-ray structural analysis of dihydroorotase from Methanococcus jannaschii co-crystallized with dihydroorotate at pH 6.5. The crystals are isomorphous with the crystals of the apoenzyme, with space group P3221 and unit-cell dimensions a = b = 111.4, c = 101.2 Å. The structure was refined to R=0.169 and Rfree = 0.186 at a resolution of 1.87 Å at room temperature. During crystallization the degradative reaction took place, and the electron density in the active site corresponds to the substrate carbamoyl aspartate. Carbamoyl aspartate interacts with the protein in the active site in a manner similar to that observed for Escherichia coli and human dihydroorotases. However, the flexible loop (residues 140-151) adopts both conformations in the crystal, loop-out and loop-in, with the loop-out conformation having higher occupancy. This contrasts with our expectations for the flexible loop to be exclusively in the loop-in conformation, which is the conformation that it adopts to stabilize the binding of the substrate in the known systems. Additional studies with substrate analogs that resemble carbamoyl aspartate and different crystallization conditions would provide further insight into the conformation of the flexible loop in this system.

Porous organic radical frameworks (PORFs), with their tunable topological architectures and distinct electronic properties, show exceptional promise for magnetic and spintronic applications. However, both integrating stable spin centers into π-conjugated porous frameworks and maintaining robust linkages pose significant synthetic challenges. In this work, two unprecedented C═C-linked radical frameworks are presented, PDA-PTMR and BTA-PTMR, engineered with distinct pore geometries. By anchoring stable polychlorotriphenylmethyl (PTM) radicals to the framework nodes, spin-½ paramagnetism in both systems is achieved. Remarkably, the PDA-PTMR framework exhibited a spin concentration of 5.45×102 3 spins mol-1, while both frameworks demonstrated intrinsic magnetic moments (S=1/2) from unpaired electron spins. Density functional theory (DFT) calculations revealed the electronic structure and spin density distributions, uncovering the origin of their magnetic behavior. Furthermore, the fabrication of organic spin valves (OSVs) is pioneered using PORF films as active layers. The PDA-PTMR-based device displayed a magnetoresistance of -23% at 25K, which is one of the highest values reported for the organic semiconductor-based OSVs. This study establishes a viable strategy for embedding magnetism in sp2-carbon-linked PORFs and provides a versatile platform for designing high-performance organic spintronic devices.

Structural, electronic, and thermodynamic characterization with spectroscopic, topological, reactivity, and molecular docking studies of diallyl sulfide.

Abstract We present a theoretical study of the generation of ion Bernstein waves and ion cyclotron waves through the parametric instability of whistler waves in a dusty plasma. The interaction begins with electron density perturbations associated with the ion Bernstein wave and the oscillatory velocity of plasma electrons driven by the whistler pump wave. This combination generates a non-linear current that excites the whistler sideband wave. The whistler pump wave and its sideband exert a ponderomotive force on the electrons, generating ion Bernstein and ion cyclotron waves. The influence of dust charge fluctuations on this wave generation process is systematically investigated. Growth rate expressions for ion Bernstein and ion cyclotron waves are derived, revealing key dependencies. The growth rate increases with higher pump wave amplitude, wave number, scattering angle, and dust grain density. In contrast, an increase in the size of the dust grain and the temperature of the electrons reduce the growth rate. A comparative analysis shows that the ion Bernstein wave exhibits greater instability than the ion cyclotron wave, resulting in a higher growth rate for the ion Bernstein wave in dusty plasma. These findings provide deeper insights into wave dynamics in dusty plasma environments, with potential implications for space and laboratory plasma studies.

Emissive properties of diphosphino-gold( i ) complexes displaying tunable TADF behaviour are strongly influenced by the electronic structure of the ligands. ONIOM calculations at the ADC(2):QM/MM level enable modeling of gold-based emitters.

The Independent Gradient Model, applied to the dynamics of carbene ligand insertion into a C-Mn bond, reveals details of electron density redistribution events, challenging earlier assumptions. The unique stereoselectivity of the reaction is rationalised by the joint use of the new Steric-Exclusion Localisation Function.