The flowerlike ZnO nanostructures, which consisted of swordlike ZnO nanorods, have been prepared by a cetyltrimethylammonium bromide (CTAB)-assisted hydrothermal process at low temperature (120 °C). The XRD pattern indicated that the flowerlike ZnO nanostructures were hexagonal. Furthermore, the SAED and HRTEM revealed that the swordlike ZnO nanorods were single crystal in nature and preferentially grew up along [001]. Finally, the mechanism for the CTAB-assisted hydrothermal synthesis of flowerlike ZnO nanostructures has been preliminarily explained by polar crystal growth theory and surfactant action theory.

A thin Fe2TiO5 layer was produced on hematite either by evaporating a TiCl4 solution on FeOOH or by a simple HF-assisted Ti treatment of FeOOH, both followed by annealing. The prepared Fe2TiO5-hematite heterostructure showed a significant enhancement in photocurrent density compared to that of the pristine hematite. For example, the sample after HF-assisted Ti treatment exhibited a significantly enhanced photocurrent of 2.0 mA/cm(2) at 1.23 V vs RHE. Moreover, the performance of the Fe2TiO5-hematite heterostructure can be further improved by coupling with Co-Pi catalysts, achieving a higher photocurrent of 2.6 mA/cm(2) at 1.23 V vs RHE. Synchrotron-based soft X-ray absorption spectroscopy analyses clearly revealed the existence of an Fe2TiO5 structure on hematite forming a heterojunction, which reduced the photogenerated hole accumulation and then improved the performance.

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This work presents the synthesis of 1D aligned Pt–Ni nanostructures with ultrahigh aspect ratio (>1000) based on the anodic aluminum oxide (AAO) template and their composition- and aspect-ratio-dependent catalytic performances to methanol oxidation reaction (MOR). The 1D aligned Pt–Ni nanostructures were electrochemically deposited in the pores of the AAO template, and the diameter and length of the synthesized nanostructures are comparable with the diameter of pores and thickness of the used AAO. The aspect ratio of the 1D aligned nanostructures can be tuned merely by altering AAO templates with the appropriate aspect ratios. Voltammetric results show that the catalytic activities (both mass activities and specific activities) of the 1D aligned Pt–Ni nanostructures for MOR are composition dependent, and the highest electrocatalytic activity exhibits at a Pt/Ni molar ratio of 1:1 (PtNi). The mechanism of the promoting effect of Ni on Pt is explained based on modification of the electronic characteristics of the surface Pt atoms (Pt 4f) by Ni atoms due to the shift in electron transfer from Ni to Pt. Moreover, the catalytic activities of the 1D aligned PtNi nanostructures are in an aspect-ratio-dependent manner and increase in the order 0D PtNi nanoparticles, 1D aligned PtNi nanostructures at aspect ratios of ∼200, 500, and 1300 due to the preferential exposure of certain crystal facets and less surface defects of the 1D aligned nanostructures. This work is believed to open new and exciting possibilities for enhancing the performance of fuel cell catalysts. Our synthesized high-aspect-ratio 1D aligned nanostructures may also be useful as sensors and in other electrochemical applications.

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A novel solvothermal process using ethylene glycol (EG) as solvent has been employed to synthesize 3D ZnO hollow microhemispheres consisting of numerous orderly and radical nanorods with diameter of about 50 nm and length of several hundred nanometers. The glycol such as EG and the solvothermal process play the critical role in the synthesis of the 3D ZnO hollow microhemispheres by the primary formation of glycolate precursors and subsequent transformation into ZnO. The morphology, structure and optical property of the 3D ZnO hollow microhemispheres have been characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), x-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL). Furthermore, the 3D ZnO hollow microhemisphere based gas sensor exhibits high sensitivity for ethanol and ammonia as well as quick response and recovery time at room temperature due to the high surface-to-volume ratio.

China has the largest aging population of all countries and faces severe aging issues. As an important indicator to measure the quality of life, the life satisfaction of elderly Chinese people has received increasing attention. Based on the cross-sectional survey data collected from 2002 to 2014, which were provided by the CLHLS (Chinese Longitudinal Healthy Longevity Survey) project as open datasets, this study investigated how the influence and importance of factors associated with life satisfaction in the elderly have changed during these years. In view of previous research and questionnaire data, demographic, physiological, psychological, economic and social characteristics were selected as potential influencing factors of life satisfaction. With the R programming language, we used IV (information value) as the indicator to measure the influence of associated factors and determined the importance of each factor by establishing a random forest model for each year. Data visualization was used to demonstrate change in each factor with the Microsofot PowerPoint 2016. The results show that, for most factors, their influence has fluctuated. Since 2002, the most significant factors have always been self-rated health, self-evaluation of economic level, economic self-sufficiency and bright personality.