Sodium-ion batteries (SIBs) are considered as a promising alternative to lithium-ion batteries, due to the abundant reserves and low price of Na sources. To date, the development of anode materials for SIBs is still confronted with many serious problems. In this work, encapsulation-type structured MoSe 2 @hollow carbon nanosphere (HCNS) materials assembled with expanded (002) planes few-layer MoSe 2 nanosheets confined in HCNS are successfully synthesized through a facile strategy. Notably, the interlayer spacing of the (002) planes is expanded to 1.02 nm, which is larger than the intrinsic value of pristine MoSe 2 (0.64 nm). Furthermore, the few-layer nanosheets are space-confined in the inner cavity of the HCNS, forming hybrid MoSe 2 @HCNS structures. When evaluated as anode materials for SIBs, it shows excellent rate capabilities, ultralong cycling life with exceptional Coulombic efficiency even at high current density, maintaining 501 and 471 mA h g −1 over 1000 cycles at 1 and 3 A g −1 , respectively. Even when cycled at current densities as high as 10 A g −1 , a capacity retention of 382 mA h g −1 can be achieved. The expanded (002) planes, 2D few-layer nanosheets, and unique carbon shell structure are responsible for the ultralong cycling and high rate performance.

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3 N 4 /SnS yolk−shell Z-scheme photocatalysts are fabricated by a simple template-assisted strategy. The L-cysteine can offer the amine groups and meanwhile anchor on the surface of g-C 3 N 4 during solvothermal reaction and thus contributes greatly to the enhanced carbon dioxide adsorption capability. This Zscheme photocatalytic reduction mechanism of Au@g-C 3 N 4 /SnS performs valuable functions in the reaction, leading to CH 4 generation much earlier and higher concentration than that of Au@g-C 3 N 4 . Meanwhile, the unique yolk−shell structure can make the light bounce back and forth in the cavity and thus enhances the availability ratio of light. The application of small amount of noble metal cocatalysts and the large Brunauer−Emmett−Teller surface areas are also benefited for the enhanced photocatalytic activities. Hence, this novel material exhibits a distinguished reduction performance for CO 2 reduction under visible light. The highest yields of CH 4 (3.8 μmol g −1 ), CH 3 OH (5.3 μmol g −1 ), and CO (17.1 μmol g −1 ) can be obtained for the sample of Au@g-C 3 N 4 /SnS (SnS 41.5%), which is higher than other latest reported g-C 3 N 4based photocatalysts for CO 2 photoreduction including coupled with semiconductors and noble metal cocatalysts. This strategy might represent a novel way for the effective transition of CO 2 to clean fuels and can also be enormous feasible utilization in the photocatalytic field.

BackgroundThe prevalence of adolescent eye disease in remote areas of the Qinghai-Tibet Plateau has rarely been reported. To understand the prevalence of common eye diseases in Tibet, we performed ocular-disease screening on students from primary and secondary schools in Tibet, and compared the prevalence to that in the Central China Plain (referred to here as the “plains area”).MethodsThe refractive status of students was evaluated with a Spot™ vision screener. The test was conducted three or fewer times for both eyes of each student and results with best correction were recorded.ResultsA total of 3246 students from primary and secondary schools in the Tibet Naidong district were screened, yielding a refractive error rate of 28.51%, which was significantly lower than that of the plains group (28.51% vs. 56.92%, p < 0.001). In both groups, the prevalence of refractive errors among females was higher than that among males.ConclusionsWe found that Tibetan adolescents had a lower prevalence of refractive errors than did adolescents in the plains area, which may be related to less intensive schooling and greater exposure to sunlight.