Changes in the structure and composition resulting from oxygen deficiency can strongly impact the physical and chemical properties of transition-metal oxides, which may lead to new functionalities ...for novel electronic devices. Oxygen vacancies (VO) can be readily formed to accommodate the lattice mismatch during epitaxial thin film growth. In this paper, the effects of substrate strain and oxidizing power on the creation and distribution of VO in WO3−δ thin films are investigated in detail. An 18O2 isotope-labeled time-of-flight secondary-ion mass spectrometry study reveals that WO3−δ films grown on SrTiO3 substrates display a significantly larger oxygen vacancy gradient along the growth direction compared to those grown on LaAlO3 substrates. This result is corroborated by scanning transmission electron microscopy imaging, which reveals a large number of defects close to the interface to accommodate interfacial tensile strain, leading to the ordering of VO and the formation of semi-aligned Magnéli phases. The strain is gradually released and a tetragonal phase with much better crystallinity is observed at the film/vacuum interface. The changes in the structure resulting from oxygen defect creation are shown to have a direct impact on the electronic and optical properties of the films.
In article number 1807857, Jian Lu and co‐workers develop a novel Fe‐based metallic glass that presents excellent catalytic performance in both efficiency and stability when compared to the ...state‐of‐the‐art. This work uncovers a new strategy for designing low‐cost and high‐performance non‐noble catalysts with respect to structural evolution and alteration of electronic properties, establishing a solid foundation in widespread catalytic applications.
It is of great significance to reveal the detailed mechanism of neighboring effects between monomers, as they could not only affect the intermediate bonding but also change the reaction pathway. This ...paper describes the electronic effect between neighboring Zn/Co monomers effectively promoting CO
electroreduction to CO. Zn and Co atoms coordinated on N doped carbon (ZnCoNC) show a CO faradaic efficiency of 93.2 % at -0.5 V versus RHE during a 30-hours test. Extended X-ray absorption fine structure measurements (EXAFS) indicated no direct metal-metal bonding and X-ray absorption near-edge structure (XANES) showed the electronic effect between Zn/Co monomers. In situ attenuated total reflection-infrared spectroscopy (ATR-IR) and density functional theory (DFT) calculations further revealed that the electronic effect between Zn/Co enhanced the *COOH intermediate bonding on Zn sites and thus promoted CO production. This work could act as a promising way to reveal the mechanism of neighboring monomers and to influence catalysis.
Epithelial-mesenchymal transition (EMT) based cancer cell invasion and metastasis has been thoroughly studied in prostate cancer. It was well known that EMT markers which have been found in benign ...prostatic hyperplasia (BPH) tissues, but system descriptions have not been described.
First, in order to construct the epithelial cells to mesenchymal cell transformation model, BPH-1 cells were cultured with supernatant of prostate matrix normal prostate stromal WPMY-1 cells, after obtaining the culture medium through a filter. After that, we observed the morphology of cells cultured for a period of time by microscopy, detected cell invasion ability by transwell assay, detected cell proliferation ability by MTT, and detected EMT marker expression by western. Finally, we treated the cells with anti-HIF-1α drugs to study their effects on EMT, and then tested several related proteins simultaneously.
The results showed that the morphology of BPH-1 cells gradually changed to fusiform after cultured with WSCM. At the same time, E-cadherin and cytokeratin levels were significantly lower than those in normal medium. Simultaneous detection of vimentin (SMA) and Snail was positive compared to normal cultured cells. At the same time, the cells were cultured with WSCM and the invasive ability was up-regulated. After treatment with anti-HIF-1α drug, E-cadherin and CK5/8 protein expression was up-regulated, but vimentin, α-SMA, and Snail expression was down-regulated, and in addition, p-Smad3 protein expression was also down-regulated after anti-HIF-1α drug was added.
The above results indicated that WSCM-1 stromal cell supernatant WSCM can induced BPH-1 cell interstitialization, and at the same time, by inducing EMT, secreting HIF-1α activates Smad3 signaling. Our study shows that inhibition of HIF-1α expression provides a new reference for clinical treatment of BPH.
Surface ligands play an important role in shape‐controlled growth and stabilization of colloidal nanocrystals. Their quick removal tends to cause structural deformation and/or aggregation to the ...nanocrystals. Herein, we demonstrate that the surface ligand based on poly(vinylpyrrolidone) (PVP) can be slowly removed from Pd nanosheets (NSs, 0.93±0.17 nm in thickness) by simply aging the colloidal suspension. The aged Pd NSs show well‐preserved morphology, together with significantly enhanced stability toward both e‐beam irradiation and electrocatalysis (e.g., ethanol oxidation). It is revealed that the slow desorption of PVP during aging forces the re‐exposed Pd atoms to reorganize, facilitating the surface to transform from being nearly perfect to defect‐rich. The resultant Pd NSs with abundant defects no longer rely on surface ligand to stabilize the atomic arrangement and thus show excellent structural and electrochemical stability. This work provides a facile and effective method to maintain the integrity of colloidal nanocrystals by slowly removing the surface ligand.
We report an effective method to remove the surface ligand from Pd nanosheets by simply aging the sample in ethanol at room temperature. This slow process allows for atomic reconstruction without altering the sheet morphology. When exposed to e‐beam irradiation or working as an electrocatalyst toward ethanol oxidation, the aged Pd nanosheets show enhanced stability.
In this study, in order to more effectively improve the biodegradation of oil in oil accident, the petroleum degrading Monomonas aeruginosa sp. was immobilized on the modified corn straw to analyze ...degradation properties, which was carbonized at different temperatures. The results indicated that after modified, the pores on the surface of corn straw increased significantly, the biomass can reach 18.25 × 10
10
CFU/g and the degradation rate of diesel could reach 59.69% after 5 days. Therefore, the modification method can further provide technical support for the immobilization technology.
Traditionally, water turbidity can be measured based on the absorption or scattering effects. Water flow velocity can be measured based on Doppler frequency shift (DFS) estimation. In this work, we ...aim to provide a simple, robust, low-cost and accurate method for both measurements by using visible light communication (VLC) modules. Signal processing methods to extract the water turbidity and water flow speed based on the VLC transceiver modules are designed and implemented.
Aims. To investigate the effect of Nrf2 activator sulforaphane (SFN) on bladder compliance and the underlying mechanisms in a rat model of partial bladder outlet obstruction (BOO). Methods. Male ...8-week-old Sprague-Dawley rats were divided into three groups. BOO rats were given daily 0.5 mg/kg sulforaphane (BOO+SFN) or vehicle (BOO) intraperitoneally for 4 weeks, while sham-operated rats were treated with vehicle (Sham). Bladder compliance, histological alteration, and collagen deposition were evaluated. The expression levels of collagen I, collagen III, MMP-1, and TIMP-1 were measured by immunohistochemistry and western blotting. Results. BOO led to a significant decrease in bladder compliance. The change was partially restored by SFN treatment. The expression of MMP-1 was significantly decreased accompanying with increased TIMP-1 expression in BOO rats compared with that in Sham rats, which was ameliorated by SFN treatment. Moreover, the increased collagen I/collagen III ratio in the BOO group was reversed by SFN treatment. Conclusions. Sulforaphane suppressed collagen deposition by regulating the MMP-1 and TIMP-1 expression and decreasing the collagen I/III expression ratio in BOO rats and improved bladder compliance.
Forecasting and evaluating the safety of mine main ventilator are helpful to prevent mine ventilation safety accidents from happening. First, on the basis of collecting and analyzing a large quantity ...of fault information of main ventilator in the nationwide coal mine, the index system was established for safety evaluation of coal mine ventilator. Second, the remark set was set up. Then, weights of safety estimation index of mine main ventilator was determined by using Analytic Hierarchy Process(AHP). With the experts grading method, single-factor matrix of fuzzy evaluation was established. Last, mathematical model of fuzzy comprehensive evaluation was settled for mine main ventilator based on fuzzy theory and used to evaluate the safety of the coal mine main ventilator. The current safety assessment level of coal mine ventilator is “basically safe” and the result can be used to make decisions.
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