INTRODUCTION E-cigarettes were invented in China, and most of the world’s e-cigarettes have been produced in China. However, awareness and use of e-cigarettes in China are lower than in Europe and America. Against the backdrop of the increasing use of e-cigarettes, the supervision of e-cigarettes in China has been almost non-existent. METHODS A literature search was carried out in five popular Chinese and English databases. These databases were PubMed, EMBASE, the Cochrane Library, China national knowledge infrastructure (CNKI), and Wan-fang database. RESULTS Twenty-one studies were identified, and a comprehensive analysis of e-cigarette awareness ratio was conducted for different regions of China and according to gender, age group, and smoking status. We also examined e-cigarette use and associated risk factors, and the relationship between e-cigarette use and smoking cessation. In 2015, the prevalence of ‘ever use’ and ‘current use’ of e-cigarettes in China were 3.1% and 0.5%, respectively. The review indicates that the awareness ratio of e-cigarettes was about 66% in Hong Kong, whereas the ratio for Tianjin was lower (43.6%). Online sales were the main channel for selling e-cigarettes to 80% of the users. Awareness of e-cigarettes has been increasing in China. Awareness was higher in men compared to women in all age groups. Nevertheless, e-cigarette use in China was lower than in developed countries. E-cigarette users were more likely to try to quit smoking, but the relationship between e-cigarette use and smoking cessation is still unclear. Governance is necessary for e-cigarette use and marketing effort. CONCLUSIONS This study investigated the awareness and use of e-cigarettes in China and the existing regulations for e-cigarette use and marketing. The lack of regulations for e-cigarette use and the unrestricted practice encourage the increase in adoption of e-cigarettes and misconceptions of the benefits of using e-cigarettes. Hence, it is crucial that the government of China prioritize the establishment and implementation of regulations for e-cigarette use and marketing.

A fast backward-jump type arc motion is observed with an arc running on rails. It is shown by the use of conductivity probes that this motion does not correspond to a continuous displacement of an ionized high-temperature region. The model of current transfer between two parallel arcs is adopted to explain the jump motion, for which a high rising speed of the arc voltage is a decisive factor. The current transfer is considered to be different from the re-ignition of a post-arc current.

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A systematic investigation and comparison of the photoluminescence (PL) quantum yields of six erbium(III) organic complexes are reported. We demonstrated that the PL quantum yield could be significantly improved by getting rid of OH and CH groups in the complexes. Moreover, perfluooctanoic acid with neither OH nor CH groups was used as a ligand to form complex with Er3+. The quantum yield of the newly synthesized erbium(III) complex was found to be as high as 2%, 100 times higher than ever reported.

Low-loss ion-exchanged sol-gel channel waveguides on silicon substrate were fabricated. Ion-exchangeable aluminosilicate glass film was fabricated by sol-gel technique. Ag(+)-Li(+) thermal ion-exchange was used to achieve single mode channel waveguide. Propagation loss of 0.50 dB/cm and coupling loss of 0.76 dB/facet were measured by cutback method. A Y-branch power splitter was also fabricated. The results demonstrate that ion-exchange technique can be applied to prepare low-loss channel waveguides in thin film structures.