A novel Sb-doped SnO2 electrode featuring high oxygen evolution potential, excellent electrocatalytic performance, and long stabilitytoward electrochemical degradation of refractory organic pollutants was constructed by designing and regenerating the microstructure of the Ti substrate. Highly ordered TiO2 nanotubes (TiO2-NTs) with three-dimensional microstructure, large specific surface area and space utilization rate could be grown in situ on Ti substrate under controlled conditions, followed by being implanted with Sb-doped SnO2 through a surfactant-assisted, sol-gel method under vacuum environment. The amount of Sb-doped SnO2 and service lifetime for the constructed electrode (TiO2-NTs/SnO2) were 2.4 and 12 times as much asthose for a traditional Sb-doped SnO2 (SnO2) electrode. Moreover, the constructed electrode performed at higher oxygen evolution potential and exhibited superior electrochemical capability to that on SnO2 electrode. Compared with low TOC removal by the SnO2 electrode, the TiO2-NTs/SnO2 electrode could completely mineralize benzoic acid (BA) under the same condition. The mineralization current efficiency and the first-order kinetic constant for BA degradation at the TiO2-NTs/SnO2 electrode were 1 and 3.5 times greater than those observed for the SnO2 electrode.

This Article puts forward a new idea to construct an electrode combining the advantages of a TiO 2 nanotube photocatalyst and an excellent Sb-doped SnO 2 electrocatalyst, which realized high electrocatalytic (EC) and photocatalytic (PC) oxidation efficiency at the same time. Under vacuum conditions, in virtue of the titanium oxide nanotubes (TiO 2 -NTs) as a template, well dispersed Sb-doped SnO 2 (particle size 20 nm) was embedded into TiO 2 -NTs (diameter 60-90 nm and wall thickness 10-20 nm), resulting in the stake structured TiO 2 -NTs/Sb-doped SnO 2 electrode (TiO 2 -NTs/SnO 2 ). The loading amount of Sb-doped SnO 2 on a TiO 2 -NTs/SnO 2 electrode is 21.4 g m -2 , which is increased by 2 times compared with the situation of direct loading Sbdoped SnO 2 on the Ti substrate (Ti/SnO 2 ). The crystal lattice parameter of SnO 2 becomes smaller, and crystal lattice parameter of TiO 2 is larger, so the combination between TiO 2 -NTs and Sb-doped SnO 2 becomes more tight. Compared with the electrochemical properties of Ti/SnO 2 , the apparent rate constant of benzoic acid (BA) conversion (k s ) on the TiO 2 -NTs/SnO 2 electrode is (1.44 ( 0.04) × 10 -4 s -1 and that of Ti/SnO 2 is (1.01 ( 0.03) × 10 -4 s -1 . Furthermore, its electrochemical stability and antideactivation properties are greatly improved, and the accelerated service lifetime of the TiO 2 -NTs/SnO 2 electrode is increased by 1.0 time. The initial instantaneous current efficiency of the degradation of BA on the TiO 2 -NTs/SnO 2 electrode is 26.8%, and that on the Ti/SnO 2 electrode is 13.3%. Compared with the PC properties of TiO 2 -NTs, the band gap of TiO 2 -NTs/SnO 2 decreases from 3.22 to 2.93 eV, and the photoconversion efficiency is raised to 26.1% from 8.2%. k s on TiO 2 -NTs/SnO 2 is (0.82 ( 0.02) × 10 -4 s -1 , and that of TiO 2 -NTs is (0.41 ( 0.02) × 10 -4 s -1 . In the photoelectrocatalytic (PEC) aspect of BA, the current densities under 3.0 V increase by 4.0, 2.1, and 0.09 mA cm -2 on the TiO 2 -NTs/SnO 2 , Ti/SnO 2 , and TiO 2 -NTs electrodes, respectively. The initial instantaneous current efficiency of the TiO 2 -NTs/SnO 2 electrode increases to 100%, which is much higher than 41.7% and 31.3% on Ti/SnO 2 and TiO 2 -NTs electrodes, respectively. k s on TiO 2 -NTs/SnO 2 is (5.26 ( 0.16) × 10 -4 s -1 , which is 3.2 times that of Ti/SnO 2 and 4.8 times that of TiO 2 -NTs. The TiO 2 -NTs/SnO 2 electrode has both excellent PC properties and excellent EC properties. After PEC degradation of BA on the electrode for 3.5 h, chemical oxygen demand (COD) removal is 100%. This research has enriched the PEC theory on the electrode's microstructured interface and developed a new idea for exploring highly efficient PEC technology.

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As the population is aging rapidly, the irrationality of residential care facility (RCF) configuration has impacted the efficiency and quality of the aged care services so significantly that the optimization of RCF configuration is urgently required. A multi-objective spatial optimization model for the RCF configuration is developed by considering the demands of three stakeholders, including the government, the elderly, and the investor. A modified immune algorithm (MIA) is implemented to find the optimal solutions, and the geographic information system (GIS) is used to extract information on spatial relationships and visually display optimization results. Jing’an District, part of Shanghai, China, is analyzed as a case study to demonstrate the advantages of this integrated approach. The configuration rationality of existing residential care facilities (RCFs) is analyzed, and a detailed recommendation for optimization is proposed. The results indicate that the number of existing RCFs is deficient; the locations of some RCFs are unreasonable, and there is a large gap between the service supply of existing RCFs and the demands of the elderly. To fully meet the care demands of the elderly, 6 new facilities containing 1193 beds are needed to be added. In comparison with the optimization results of other algorithms, MIA is superior in terms of the calculation accuracy and convergence rate. Based on the integration of MIA and GIS, the quantity, locations, and scale of RCFs can be optimized simultaneously, effectively, and comprehensively. The optimization scheme has improved the equity and efficiency of RCF configuration, increased the profits of investors, and reduced the travel costs of the elderly. The proposed method and optimization results have reference value for policy-making and planning of RCFs as well as other public service facilities.

Based on the requirement of high-power linear propulsion system, a novel twelve-phase linear induction motor (LIM) with double-sided long stators was designed, and the winding construction of twelve-phase LIM was presented in this paper. On the basis of this, the mathematical model of ABC coordinates for this novel motor was derived, and the rule of the asymmetry of end-winding leakage inductance of the twelve-phase LIM with double-sided long stators, which is determined by the relative space position of the each phase end-winding in the motor, and then this rule was compared with the law of the asymmetry of end-winding leakage inductance of the multi-phase rotating motor. Simulation model of the motor was established, and the electromagnetic properties of the motor is calculated.