Au-Plasmon-induced resonance energy transfer modulates the charge carrier energetics of ZnO nanosheets to trigger the stoichiometric conversion of methane into ethane and hydrogen.

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To obtain the correlation of microstructural characteristics and toughness in a novel high-strength low-carbon bainitic structural steel with medium and heavy plate after multipass welding, a welding thermal simulation experiment was conducted to simulate different subregions in the reheated coarse-grained heat-affected zones (CGHAZ). The microstructure evolution was then analyzed and factors that influence the fracture behavior were studied. The results show that the brittle zone appeared in subcritical reheated CGHAZ, and the fractured morphology was cleavage fracture. Supercritical reheated CGHAZ had the highest impact toughness, and the fractured morphology was primarily the ductile fracture with dimples formed via the micropore polycondensation mechanism. With an increase in the secondary pass welding thermal cycle peak temperature (t p2), the average length size of martensite and austenite (M-A) decreased from 9 to 2 lm. The coarsening of M-A constituents was the main reason for decrease in the crack initiation absorbed energy. A large number of retained austenite and cementite precipitates in subcritical reheated CGHAZ clearly worsened the impact toughness, and the massive austenite and cementite precipitates more than offset the beneficial effects of high-angle boundaries. This phenomenon led to disappearance of the effect of high-angle grain boundary of prior austenite and lath bainite on arresting crack propagation. In supercritical reheated CGHAZ, crack propagation absorbed energy was increased because of grain refinement, fine precipitates, lamellar residual austenite at corners, and high-angle grain boundary.

This work demonstrates the long‐range redox reactivity of gold plasmon‐generated hot electrons for solar‐driven CO2 conversion. A series of Au NR@ZnO core‐shell photocatalysts with a tunable shell thickness are rationally designed to achieve the solar‐to‐CH4 conversion, where the hot plasmonic electrons‐induced photoreduction takes place on the polar oxide moiety. The shell thickness‐independent activity implies that the core, gold nanorods, plays a dominant role in the CH4 generation. The ZnO metal oxide semiconductor shell is beneficial to prolong the lifetime of hot electrons, thereby enhancing the photocatalytic efficiency. However, the thickness of ZnO shell is not relevant to the production rate. Both of these two parts are co‐excited by solar light and synergetic enhance the photocatalytic activity.

Background: Autonomic nervous regulation plays a critical role in end-stage kidney disease (ESKD) patients with cardiovascular complications. However, studies on autonomic regulation in ESKD patients are limited to heart rate variability (HRV) analysis. Skin sympathetic nerve activity (SKNA), which noninvasively reflects the sympathetic nerve activity, has not been used in ESKD patients.Methods: Seventy-six patients on maintenance hemodialysis (MHD) treatment (a 4-h HD session, three times a week) were enrolled. Utilizing a noninvasive, single-lead, high-frequency recording system, we analyzed the dynamic change in HRV parameters and SKNA during HD. The different characteristics between the subgroups divided based on interdialytic weight gain (IDWG, <3 kg or ≥3 kg) were also demonstrated.Results: After the HD, values for heart rate (75.1 ± 11.3 to 80.3 ± 12.3 bpm, p < 0.001) and LF/HF (1.92 ± 1.67 to 2.18 ± 2.17, p = 0.013) were significantly higher than baseline. In subgroup analysis, average voltage of skin sympathetic nerve activity (aSKNA) in IDWG ≥3 kg group was lower than the IDWG <3 kg group at the end of MHD (1.06 ± 0.30 vs 1.32 ± 0.61 μV, p = 0.046). Moreover, there was a linear correlation between mean heart rate (HR) and aSKNA in low IDWG patients (p < 0.001), which was not found in high IDWG patients. At the 1-year follow-up, high IDWG patients had a higher incidence of cardiovascular hospitalization (p = 0.046).Conclusions: In MHD patients, a gradual activation of sympathetic nerve activity could be measured by HRV and aSKNA. A lower aSKNA at the end of HD and a loss of HR-aSKNA correlation in overhydrated patients were observed. Extensive volume control is promising to improve the autonomic nervous function and clinical outcomes in this population.

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The purpose of this study is to use the coronary computed tomography angiography (CCTA) to simulate the coronary blood flow with different theoretical flow models by using not only the computation fluid dynamics (CFD) method, but also additional patient boundary conditions obtained with echocardiography, and evaluate the feasibility of simulated fractional flow reserve (FFR CTS ), compared with the invasive CTA-based FFR. The laminar and three turbulence models (k-ε(kepsilon), k-ω(k-omega), SST (Menter's shear stress transport)) were implemented to predict coronary blood flow. The study investigates an ideal stenosis model and six patients, with invasive FFR measurements. Three-dimensional reconstructions of coronary arteries of six subjects were performed from CCTA images of 320-detector scanner. The measured velocity profile of the left ventricular outflow tract from the echocardiography was employed for the inlet velocity in simulation. The pressure waveform of the patient aortic blood flow was used as the pressure profile at the outlet. With simulations, we found that the maximum velocity in the stenotic coronary artery reached about 395 cm s −1 , which was about 2.4 times faster than the inlet velocity of 165 cm s −1 for the patient with coronary stenosis diagnosed 50%-75% on CTA. The pressure drop across the stenosis was about 28 mmHg. Meanwhile, the value of FFR CTS using the laminar flow pattern was 0.788 closely to its invasive FFR of 0.79. In conclusion, this study demonstrated that the CFD method has moderate more blood flow information to assess the hemodynamic significance of the coronary blood flow and calculate the non-invasive FFR CTS values, which were very close to those measured with invasive FFR. Abbreviations3D three-dimensional CCTA coronary computed tomography angiography CFD computation fluid dynamics CT computed tomography FFR fractional flow reserve FFR CT computational of fractional flow reserve using coronary computed tomography angiography FFR CTS simulated fractional flow reserve using coronary computed tomography angiography and computational fluid dynamics simulation in this studyRECEIVED

Influences of cooling time (welding heat input) on microstructure, impact toughness and the fracture mechanism of the weakest CGHAZ (coarse-grained heat-affected zone) in a novel highstrength low-carbon microalloyed construction steel were studied for the purpose of laying a theoretical foundation for developing welding support technologies. When the cooling time (t 8/5 ) was increased, the microstructure changed from dot shape M-A constituents and lath martensite/bainite to slender and blocky M-A constituents and coarse granular bainite. Accordingly, the impact toughness deteriorated. Large blocky M-A constituents seriously reduced the impact absorbed energy during crack initiation. For coarse bainite, the high-misorientation boundary almost disappeared. Therefore, crack initiation energy determines the cleavage fracture micromechanism of high heat input construction steel.