Oxygen reduction reaction for generating H2O2 through a piezo-catalytic process over bismuth oxychloride

Oxygen reduction reaction (ORR) for generating H2O2 through green pathways have gained much attention in recent years. Herein, we introduce a piezo‐catalytic approach to obtain H2O2 over bismuth oxychloride (BiOCl) through an ORR pathway. The piezoelectric response of BiOCl was directly characterized by piezoresponse force microscopy (PFM). The BiOCl exhibits efficient catalytic performance for generating H2O2 (28 μmol h−1) only from O2 and H2O, which is above the average level of H2O2 produced by solar‐to‐chemical processes. A piezo‐catalytic mechanism was proposed: with ultrasonic waves, an alternating electric field will be generated over BiOCl, which can drive charge carriers (electrons) to interact with O2 and H2O, then to form H2O2

Association Between Intraoperative Steroid and Postoperative Mortality in Patients Undergoing Craniotomy for Brain Tumor

BACKGROUND: Despite the widespread use of intraoperative steroids in various neurological surgeries to reduce cerebral edema and other adverse symptoms, there is sparse evidence in the literature for the optimal and safe usage of intraoperative steroid administration in patients undergoing craniotomy for brain tumors. We aimed to investigate the effects of intraoperative steroid administration on postoperative 30-day mortality in patients undergoing craniotomy for brain tumors. METHODS: Adult patients who underwent craniotomy for brain tumors between January 2011 to January 2020 were included at West China Hospital, Sichuan University in this retrospective cohort study. Stratified analysis based on the type of brain tumor was conducted to explore the potential interaction. RESULTS: This study included 8,663 patients undergoing craniotomy for brain tumors. In patients with benign brain tumors, intraoperative administration of steroids was associated with a higher risk of postoperative 30-day mortality (adjusted OR 1.98, 95% CI 1.09-3.57). However, in patients with malignant brain tumors, no significant association was found between intraoperative steroid administration and postoperative 30-day mortality (adjusted OR 0.86, 95% CI 0.55-1.35). Additionally, administration of intraoperative steroids was not associated with acute kidney injury (adjusted OR 1.11, 95% CI 0.71-1.73), pneumonia (adjusted OR 0.89, 95% CI 0.74-1.07), surgical site infection (adjusted OR 0.78, 95% CI 0.50-1.22) within 30 days, and stress hyperglycemia (adjusted OR 1.05, 95% CI 0.81-1.38) within 24 h after craniotomy for brain tumor. CONCLUSION: In patients undergoing craniotomy for benign brain tumors, intraoperative steroids were associated with 30-day mortality, but this association was not significant in patients with malignant brain tumors

Structure identification and variable selection in geographically weighted regression models

<p>Geographically weighted regression (GWR) is an important tool for exploring spatial non-stationarity of a regression relationship, in which whether a regression coefficient really varies over space is especially important in drawing valid conclusions on the spatial variation characteristics of the regression relationship. This paper proposes a so-called GWGlasso method for structure identification and variable selection in GWR models. This method penalizes the loss function of the local-linear estimation of the GWR model by the coefficients and their partial derivatives in the way of the adaptive group lasso and can simultaneously identify spatially varying coefficients, nonzero constant coefficients and zero coefficients. Simulation experiments are further conducted to assess the performance of the proposed method and the Dublin voter turnout data set is analysed to demonstrate its application.</p

Effects of the Substitution of 20% Nd for La or Doping with 20% C on the Magnetic Properties and Magnetocaloric Effect in LaFe11.5Si1.5 Compound

The effects of element substitution and element doping on the magnetic properties and magnetocaloric effect of the LaFe11.5Si1.5 compound were investigated. The crystals of the LaFe11.5Si1.5, La0.8Nd0.2Fe11.5Si1.5, and LaFe11.5Si1.5C0.2 compounds all showed cubic NaZn13-type structures, but the lattice of the La0.8Nd0.2Fe11.5Si1.5 shrank and the lattice of the LaFe11.5Si1.5C0.2 expanded. All three compounds had the characteristic of first-order magnetic transition due to the obvious itinerant-electron metamagnetic (IEM) transition occurring above Curie temperature (TC). For the LaFe11.5Si1.5, La0.8Nd0.2Fe11.5Si1.5, and LaFe11.5Si1.5C0.2 compounds, the TC were approximately 194 K, 188 K, and 232 K, respectively. Meanwhile, the maximum magnetic entropy changes (−ΔSM) under a magnetic field change of 0–3 T were approximately 18.7 J/kg·K, 22.8 J/kg·K, and 16.4 J/kg·K, respectively. The TC was mainly affected by the lattice constant. Furthermore, the −ΔSM was mainly affected by the latent heat of the first-order magnetic transition

Brief Review of Epitaxy and Emission Properties of GaSb and Related Semiconductors

Groups III–V semiconductors have received a great deal of attention because of their potential advantages for use in optoelectronic and electronic applications. Gallium antimonide (GaSb) and GaSb-related semiconductors, which exhibit high carrier mobility and a narrow band gap (0.725 eV at 300 K), have been recognized as suitable candidates for high-performance optoelectronics in the mid-infrared range. However, the performances of the resulting devices are strongly dependent on the structural and emission properties of the materials. Enhancement of the crystal quality, adjustment of the alloy components, and improvement of the emission properties have therefore become the focus of research efforts toward GaSb semiconductors. Molecular beam epitaxy (MBE) is suitable for the large-scale production of GaSb, especially for high crystal quality and beneficial optical properties. We review the recent progress in the epitaxy of GaSb materials, including films and nanostructures composed of GaSb-related alloys and compounds. The emission properties of these materials and their relationships to the alloy components and material structures are also discussed. Specific examples are included to provide insight on the common general physical and optical properties and parameters involved in the synergistic epitaxy processes. In addition, the further directions for the epitaxy of GaSb materials are forecasted

Effect of Post Thermal Annealing on the Optical Properties of InP/ZnS Quantum Dot Films

Abstract The enhancement of optical properties via thermal annealing on InP/ZnS core/shell quantum dot (QD) film was investigated in this work. The increase of emission intensities of the QD films was observed after thermal annealing at 180 °C for 5 min. Through temperature dependence photoluminescence (TDPL) and power dependence photoluminescence (PL) measurement, the peak located at the low-energy shoulder was confirmed to be localized state emission and the high energy one comes from free-carrier emission. Moreover, from the TDPL spectra of the sample annealed at 180 °C for 5 min, the full width at half maximum (FWHM) of localization state emission was nearly the same before which is 250 K and then decreased with increasing temperature. However, the FWHM was decreased significantly when temperature increased in the untreated sample. We conclude that the escape of localization states with increasing temperature contributes to this anomaly phenomenon. Our studies have significance on the application of QDs in electroluminescence devices and down-conversion light-emitting devices

NO₂ Adsorption Sensitivity Adjustment of As/Sb Lateral Heterojunctions through Strain: First Principles Calculations

Strain engineering is an effective way to adjust the sensing properties of two-dimensional materials. In this paper, lateral heterojunctions (LHSs) based on arsenic and antimony have been designed along the armchair (AC) or zigzag (ZZ) edges. The adsorption and sensing characteristics of As/Sb LHSs to NO2 before and after applying different types of strain are calculated by first principles. The band gaps of all As/Sb heterostructures are contributed by As-p and Sb-p orbitals. In addition, the adsorption energy of As/Sb ZZ-LHS with −4% compression strain is the largest. Furthermore, its work function changes significantly before and after the adsorption of NO2. Meanwhile, strong orbital hybridizations near the Fermi level are observed and a new state is yielded after applying compressive strain. These results indicate that the As/Sb LHS with ZZ interface under −4% compression strain possesses the best sensing properties to NO2. This work lays the foundation for the fabrication of high-performance NO2 gas sensors. High-performance gas sensors can be used to track and regulate NO2 exposure and emission, as well as to track NO2 concentrations in the atmosphere and support the assessment of air quality

The Design and Implementation of Geospatial Information Verification Middle Platform for Natural Resources Government Affairs

Geospatial Information Verification Mid-End Platform for Natural Resource Administration is designed in response to issues such as repeated development, low scalability, and inconsistent verification rules in existing approval and supervision application systems. We first discussed the architecture of the middle platform and micro-services and also examined the business requirements. Secondly, we presented the architecture of the spatial information verification platform. Finally, the application method in the construction land approval business is introduced. Practical applications proved that the spatial information verification platform is highly scalable and maintainable, with reusable business components and data services for a variety of government affairs application systems

Internal Electric Field Assisted Photocatalytic Generation of Hydrogen Peroxide over BiOCl with HCOOH

Hydrogen peroxide (H₂O₂) is a superb, clean, and versatile reagent. However, large-scale production of H₂O₂ is manufactured through nongreen methods that motivate people to develop more efficient and green technologies as alternatives. As a novel and green technology used for H₂O₂ generation, the efficiency of photocatalysis is still far from satisfactory. Here, we demonstrate a novel and efficient path of the generation of H₂O₂ in BiOCl photocatalysis but not the direct electron reduction of O₂ or hole oxidation of OH^– to H₂O₂. Super high production (685 μmol/h) of H₂O₂ by the addition of HCOOH as the hole shuttle was realized over BiOCl nanoplates. In this photocatalytic system, the BiOCl supplied abundant photoinduced holes to initiate HCOO^• radical. The HCOO^• further reacts with OH^– to •OH which is proven to be the source of the H₂O₂. Apart from HCOOH, O₂ also played important roles. The O₂ not only promoted the reaction through the cycle between Bi³⁺ and Bi, which decreased the combination of carriers, but also avoided the carbonation of surfaces, thus achieving the high production of H₂O₂ (1020 μmol/h). In this work, we shed light on a deep understanding of the photocatalytic evolution of H₂O₂ in a novel perspective and achieve high production