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Atomically precise Au nanoclusters (NCs) with discrete energy levels can be used as photosensitizers for CO2 reduction. However, tight ligand capping of Au NCs hinders CO2 adsorption on its active sites. Here, a new hybrid material is obtained by anchoring of thiol functionalized terpyridine metal complexes (metal=Ru, Ni, Fe, Co) on Au NCs by ligand exchange reactions (LERs). The anchoring of Ru and Ni complexes on Au25 NC (Au25−Ru and Au25−Ni) leads to adequate CO2 to CO conversion for photocoupled electrocatalytic CO2 reduction (PECR) in terms of high selectivity, with Faradaic efficiency of CO (FECO) exceeding 90 % in a wide potential range, remarkable activity (CO production rate up to two times higher than that for pristine Au25PET18) and extremely large turnover frequencies (TOFs, 63012 h−1 at −0.97 V for Au25−Ru and 69989 h−1 at −1.07 V vs. RHE for Au25−Ni). Moreover, PECR stability test indicates the excellent long‐term stability of the modified NCs in contrast with pristine Au NCs. The present approach offers a novel strategy to enhance PECR activity and selectivity, as well as to improve the stability of Au NCs under light illumination, which paves the way for highly active and stable Au NCs catalysts. [ABSTRACT FROM AUTHOR]

BackgroundThe energy deposition behavior of β particles in transducer material is an important issue in the simulation of a betavoltaic battery, which is usually performed by Monte Carlo software Casino and MCNP (Monte Carlo N Particle Transport Code). However, it is difficult to simulate the continuous energy spectrum of β particles by Casino software. The commercial software MCNP is subject to many restrictions on its copyright, it is very necessary to study the energy deposition of β particles in transducer materials based on the universal open-source Monte Carlo program Geant4 (GEometry ANd Tracking, version 4).PurposeThis study aims to develop a model based on Geant4 to study the energy deposition of β particles in betavoltaic battery transducer materials.MethodsBased on the framework of Geant4 software, a general simulation model of energy deposition behavior was developed. The continuous β spectrum, the self-absorption of radioactive source, and the backscattering of β particles on the source-transducer interface were taken into account completely in this model for the Monte-Carlo simulation study, and the computation results were compared with that of Casino software.ResultsSimulation comparison results show that this simulation model can accurately simulate the energy deposition behavior of β particles in the transducer materials of betavoltaic battery.ConclusionsSimulation model proposed in this study can be used to study the energy deposition of β particles in the transducer materials with advantages of convenient application, open software and easy extension to other source-transducer combinations.

Background: Reperfusion therapy is the most effective approach to resolve coronary occlusion, but myocardial injury caused by excessive inflammation during myocardial ischemia–reperfusion will also pose a new threat to health. Our prior study revealed the expression pattern of interleukin‐38 (IL‐38) in the peripheral blood serum of patients with ischemic cardiomyopathy and the role of IL‐38 in acute myocardial infarction in mice. However, its role and potential mechanisms in myocardial ischemia/reperfusion injury (MIRI) remain to be determined. Methods and Results: The left anterior descending artery of C57BL/6 mice was transiently ligated to induce the MIRI model. We found that MIRI induced the expression of endogenous IL‐38, which was mainly produced by locally infiltrating macrophages. Overexpression of IL‐38 in C57BL/6 mice attenuated inflammatory injury and decreased myocardial apoptosis after myocardial ischemia–reperfusion. Furthermore, IL‐38 inhibited lipopolysaccharide‐induced macrophage inflammation in vitro. Cardiomyocytes cocultured with the supernatant of IL‐38‐ and troponin I‐treated macrophages showed a lower rate of apoptosis than controls. Conclusions: IL‐38 attenuates MIRI by inhibiting macrophage inflammation. This inhibitory effect may be partially achieved by inhibiting the activation of NOD‐like receptor pyrin domain‐related protein 3 inflammasome, resulting in decreased expression of inflammatory factors and reduced cardiomyocyte apoptosis. [ABSTRACT FROM AUTHOR]

Au catalysts have drawn broad attention for catalytic CO oxidation. However, a molecular-level understanding of the reaction mechanism on a fast time-resolved scale is still lacking. Herein, we apply in situ DRIFTS and UV-Vis spectroscopy to monitor the rapid dynamic changes during CO oxidation over Au/TiO2. A pronounced transient inactivation effect likely due to a structural change of Au/TiO2 induced by the reactants (CO and O2) is observed at the beginning of the reaction. The transient inactivation effect is affected by the ratio of CO and O2 concentrations. More importantly, during the unstable state, the electronic properties of the Au particles change, as indicated by the shift of the CO stretching vibration. UV-Vis spectroscopy corroborates the structure change of Au/TiO2 surface induced by the reactants, which leads to a weakening of the Au catalyst's ability to be oxidized (less O2 adsorption), resulting in the transient inactivation effect. A molecular-level understanding of the Au-catalyzed CO oxidation on a fast time-resolved scale is still lacking. Here the authors monitor the rapid dynamic changes during CO oxidation over Au/TiO2 using in situ DRIFTS and UV-Vis spectroscopy, and reveal that the catalyst undergoes a surprising structural change at the beginning of the reaction. [ABSTRACT FROM AUTHOR]

In order to solve the problem of workability and durability of concrete caused by poor particle shape and morphology of manufactured sand and high content of stone powder, which leads to crack problems of concrete, the tensile strength, elastic modulus, shrinkage performance and adiabatic temperature rise performance of manufactured sand concrete were studied in this paper. And the cracking risk factor (the reciprocal of the anti cracking safety factor) of the concrete with the special admixtures and the crack resistant functional materials was calculated by according to GB 50496--2018. The experimental results show that the elastic modulus and tensile strength at the age of 28 d of the test concrete are increased from 31.0 GPa to 34.6 GPa and 2.91 MPa to 4.23 MPa, respectively. The shrinkage performance and adiabatic temperature rise of the concrete are reduced from 98 με to 65 με and 38.9 °C to 38.4 °C, respectively. The risk factors of surface and center crack resistance of mass concrete floor are 0.52 and 0.75, so the concrete under inspection will not crack. [ABSTRACT FROM AUTHOR]