Controlled Synthesis of Large-Area Oriented ZnO Nanoarrays.

Large-area oriented ZnO nanoarrays (including nanowire, nanorod, and nanotube) on ITO glass substrates are synthesized via the simple hydrothermal, electrodeposition, and electrochemical etching approach. The morphology of ZnO nanoarrays is controlled by adjusting the reaction temperature, reaction time, and current density. The scanning and transmission electron microscopy (SEM and TEM) results indicate the successful preparation of large-area oriented ZnO nanoarrays with different types, and the energy-dispersive X-microanalysis spectrum (EDS) and X-ray diffraction (XRD) results confirm that the composition of the obtained nanoarrays is ZnO. More importantly, the as-prepared ZnO nanotube arrays are observed with about a 40% increase in ultraviolet absorption intensity compared to the ZnO nanowire/nanorod arrays, due to having larger specific surface areas. The as-prepared different types of ZnO nanoarrays have great potential for applications in low-cost and high-performance optoelectronic devices.

Advances in Self-Powered Ultraviolet Photodetectors Based on P-N Heterojunction Low-Dimensional Nanostructures.

Self-powered ultraviolet (UV) photodetectors have attracted considerable attention in recent years because of their vast applications in the military and civil fields. Among them, self-powered UV photodetectors based on p-n heterojunction low-dimensional nanostructures are a very attractive research field due to combining the advantages of low-dimensional semiconductor nanostructures (such as large specific surface area, excellent carrier transmission channel, and larger photoconductive gain) with the feature of working independently without an external power source. In this review, a selection of recent developments focused on improving the performance of self-powered UV photodetectors based on p-n heterojunction low-dimensional nanostructures from different aspects are summarized. It is expected that more novel, dexterous, and intelligent photodetectors will be developed as soon as possible on the basis of these works.

Cigarette smoking and all-cause mortality in rural Chinese male adults: 15-year follow-up of the Anqing cohort study.

BACKGROUND: According to the Global Burden of Disease Study 2017, smoking is one of the leading four risk factors contributing to deaths in China. We aimed to evaluate the associations of smoking with all-cause mortality in a Chinese rural population. METHODS: Male participants over age 45 (n = 5367) from a large familial aggregation study in rural China, were included in the current analyses. A total of 528 former smokers and 3849 current smokers accounted for 10 and 71.7% of the cohort, respectively. Generalized Estimating Equations were used to evaluate the association between baseline smoking status and mortality, adjusting for pertinent covariates. RESULTS: There were 579 recorded deaths during the 15-year follow-up. Current smokers (odds ratio [OR],1.60; 95% CI,1.23-2.08) had higher all-cause mortality risks than nonsmokers. Relative to nonsmokers, current smokers of more than 40 pack-years ([OR],1.85; 95% CI,1.33-2.56) had a higher all-cause mortality risk. Compared to nonsmokers, current smokers who started smoking before age 20 ([OR],1.91; 95% CI,1.43-2.54) had a higher all-cause mortality risk, and former smokers in the lower pack-year group who quit after age 41 (median) ([OR],3.19; 95% CI,1.83-5.56) also had a higher risk of death after adjustment. Furthermore, former smokers who were also former drinkers had the highest significant risk of mortality than never smokers or drinkers. (P for interaction = 0.034). CONCLUSIONS: This study provides evidence that current smokers and former smokers have a higher mortality risk than nonsmokers and would benefit from cessation at a younger age.