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Herein, the lasing action of fabricated bulged CH3NH3PbBr3 microwires is demonstrated with features of a low threshold, narrow linewidth, single‐mode operation, and high intensity. Benefiting from the bulged end facets, the CH3NH3PbBr3 microwires are feasible for constructing a high‐brightness, whispering‐gallery‐mode(WGM)‐type, and single‐mode laser while suppressing Fabry–Pérot‐type multi‐mode lasing. Numerical simulation unveils that the bulged end facets result in the significantly reduced reflectivity of fundamental waveguided modes. The obtained microlasers require neither complex structures (such as distributed Bragg reflector) nor careful pumping adjustment, suggesting the practical feasibility of a higher single‐mode lasing intensity than conventional WGM perovskite microlasers. The results provide new routes to realize high‐performance perovskite microlasers and their potential application in sensing refractive index. [ABSTRACT FROM AUTHOR]

To improve the reliability and intelligent level of the AC transmission system, the radial basis function-based proportional-integral-derivative (RBF-PID) control method for the motor actuator used in the 550 kV gas-insulated switchgear (GIS) disconnector is proposed. According to the dynamic mathematical model of the motor actuator, the main structure of the RBF neural network based on the gradient descent method for learning algorithm is constructed. An identification function is formed by taking values of the output error square, and then by gathering information on the real-time tuning parameters of PID. Based on that, the simulation of the control system is constructed. The comparative analyses of the tracking control characteristics and the servo following error of the disconnector's contact speed between double-loop PID and RBF-PID are done through the computational and experiment methods, respectively. The results show that 550 kV GIS disconnector with the motor actuator by the RFB-PID control method has better controllability, and the servo following error is controlled within 0.1 m/s.

In this work, a novel ZIF-8 and ZIF-67 co-modified TiO2 nanospheres with highly efficient degradation of organic pollutants was synthesized successfully. The structure, morphology, and chemical components of ZIF-8-67@TiO2 were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffractometer, infrared spectroscopy, and X-ray Photoelectron Spectroscopy. The optical properties of all samples were analyzed by UV–Visible diffuse reflectance spectroscopy diffraction. It is found that after the growth of ZIFs on the surface of TiO2 nanospheres, the specific surface area of TiO2 was greatly improved. The light sensitivity area of TiO2 is extended to include both the visible and ultraviolet spectrums by loading ZIF-8 and ZIF-67 nanoparticles. In addition, the construction of Z-scheme heterojunction also improves the separation of photocarriers, and the transfer of photogenerated charges between ZIFs and TiO2 is accelerated by the formed N–Ti–O bonds, thus extending the lifetime of photogenerated charges and enhancing the catalytic activity. The ternary ZIF-8-67@TiO2 demonstrates excellent photocatalytic activity and photoelectrochemical performance. The corresponding first-order kinetic constant (16.56 × 10−3 min-1) of ZIF-8-67@TiO2 is 11.6 times more than that of TiO2(1.43 × 10−3 min−1). Especially, in strong alkaline environment (pH = 12), methylene blue can be almost completely degraded within 15 min. Furthermore, ZIF-8-67@TiO2 exhibits the maximum photocurrent density (36.69 µA/cm2), which is 15.7 times greater than that of TiO2 (2.33 µA/cm2). Therefore, the co-modified TiO2 nanospheres with ZIF-8 and ZIF-67 can serve as a promising route to fabricate photocatalytic membranes for use in the water treatment industry. [ABSTRACT FROM AUTHOR]

Organic pollutants in wastewater have attracted much interest due to their potential threats to the environment and human health. Herein, a reasonably designed multifunctional TiO 2 /g-C 3 N 4 /Ag (TCA) film with the intrinsic Raman signals has been exploited, which exhibits prominent surface-enhanced Raman scattering (SERS) sensitivity, photocatalytic activity, and photoelectrochemical (PEC) conversion performance. For Rhodamine 6G (R6G) as probe molecules, the detection limit of TCA reaches 10−12 M and the SERS enhancement factor is up to 4.94 × 105. The relative standard deviation (RSD) of Raman vibration near 1650 cm−1 is about 6.79%, which proves the good uniformity of the TCA substrate. Meanwhile, the TCA film exhibits excellent photocatalytic and PEC performance with the largest photodegradation rate of 64.95% and the biggest transient photocurrent of 225.89 μA/cm2 compared with other samples. In addition, TCA also showed good self-cleaning and reusable performance under simulated sunlight irradiation. The excellent multifunction of TCA mainly originates from the synergistic effect of TiO 2 , g-C 3 N 4 , and Ag, including the increased specific surface area, enhanced active sites, and promoted photogenerated charge separation and transportation. These facts manifest that the TCA film can be used for quantitative monitoring and facile decomposing of R6G. [ABSTRACT FROM AUTHOR]

Objectives Cognitive impairment caused by cerebrovascular disease accounts for more than half of vascular dementia. However, neuropsychological tests are limited by their subjectivity. Additional effective approaches to evaluate cognitive impairment in patients with cerebrovascular disease are necessary. Method One hundred and thirty-two patients with cerebrovascular disease were recruited. One hundred participants met the criteria and completed neuropsychological scales. Sixty-nine participants proceeded with polysomnography, and 63 of them had their peripheral blood biomarkers measured. According to Mini-Mental State Examination scores, patients were divided into cognitively impaired and cognitively normal groups. The differences in biomarkers and sleep parameters between the groups were compared, and decision tree models were constructed to evaluate the evaluation ability of these indicators on cognitive decline. Results The integrated decision tree model of sleep parameters yielded an area under curve (AUC) of 0.952 (95% confidence interval [CI]: 0.911–0.993), while that of plasma biomarkers yielded an AUC of 0.872 (95% CI: 0.810–0.935) in the assessment of cognition status. Then the participants were automatically clustered into mild and severe cognitive impairment groups by multiple neuropsychological test results. The integrated plasma biomarker model showed an AUC of 0.928 (95% CI: 0.88–0.977), and the integrated sleep parameter model showed an AUC of 0.851 (95% CI: 0.783–0.919) in the assessment of mild/severe cognitive impairment. Discussion Integrated models which consist of sleep parameters and plasma biomarkers can accurately evaluate dementia status and cognitive impairment in patients with cerebral small vessel disease. This innovative study may facilitate drug development, early screening, clinical diagnosis, and prognosis evaluation of the disease. [ABSTRACT FROM AUTHOR]

In this work, a two-dimensional (2D) TiO2/SnS2 nanosheet heterojunction with a novel face-to-face structure was fabricated by a two-step hydrothermal method. The morphology, microstructure, chemical components, as well as optical features, photocatalytic activity, photoelectrochemical (PEC) performance and catalytic mechanism of TiO2/SnS2 were systematically investigated. The results indicate that the 2D TiO2/SnS2 sheet-like heterojunction can enhance the photocatalytic activity for refractory contaminants including methyl orange (MO), methylene blue (MB), rhodamine B (RhB), and tetracycline antibiotics (TCs). TiO2/SnS2 with a mole ratio of Sn : Ti = 0.15 : 1 possesses the best photocatalytic activity and PEC performance. The corresponding photocurrent density (∼3.79 μA cm−2) is 3.4 and 2.6 times higher than those of TiO2 (∼1.11 μA cm−2) and SnS2 (∼1.45 μA cm−2). Enhanced photocatalytic activity and PEC performance are ascribed to the synergistic effect of TiO2/SnS2 heterostructures, including (i) Z-scheme band alignments, which can effectively inhibit photogenerated carrier recombination, (ii) modulation of narrow band SnS2, which can broaden the visible photoabsorption region, and (iii) face-to-face structures, which can provide a convenient transport channel for photoinduced carriers. [ABSTRACT FROM AUTHOR]

Ultrathin mixed metallic phase (1T) and semiconducting phase (2H) MoS2 nanosheet decorated TiO2 nanorod arrays were prepared through a simple two-step hydrothermal method. By modulating the subsequent annealing conditions, the gradual phase transformation of MoS2 from 1T to 2H was observed. The mixed phase MoS2 shows superior photocatalytic hydrogen evolution to 2H phase MoS2 and noble metal Pt. The distinguishable optical and photoelectrochemical behaviors of mixed phase MoS2 and 2H phase MoS2 reflect their different internal structures and charge transfer mechanisms. The existence of the abundant metal like 1T phase in the mixed phase MoS2 accelerates the electron transport between TiO2 and MoS2 more effectively and decreases the recombination of electron–hole pairs, thus enabling preferable photocatalytic performance compared to 2H phase MoS2. The possible electron transfer mechanism between MoS2 and TiO2 is also illustrated. [ABSTRACT FROM AUTHOR]