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Semiconducting/insulating polymer blends are promising materials for use in organic thin film transistor (OTFT) applications. Here, vertically phase-separated poly(3-hexylthiophene) (P3HT)-top and poly(methyl methacrylate) (PMMA)-bottom blend films were developed for the facile fabrication of OTFTs with excellent electrical properties. The microstructures of the blend films could be adjusted simply by altering the film processing conditions, which impacted the electrical properties of the OTFTs based on the blend films. A decrease in the P3HT content of the blend film significantly reduced the interface roughness between the semiconductor (P3HT) and dielectric (PMMA) layers, which reduced charge trapping or scattering, thereby increasing the field-effect mobility. A higher solution concentration tended to increase the drying time during film deposition, which allowed the P3HT molecules to self-organize over a long period of time. This led to an increase in the ordering of the phase-separated P3HT film, which significantly improved the device performance. TFTs based on a P3HT/PMMA (1/39 w/w) film prepared from a 4 wt% blend solution showed the best field-effect performance with a saturated field-effect mobility of 0.022 cm 2 V À1 s À1 and an I on /I off current ratio of 2 Â 10 5 . The vertically stratified P3HT/PMMA films were also suitable for the fabrication of all-polymer TFT devices on flexible substrates.

Novel inexpensive, light, flexible, and even rollup or wearable devices are required for multi-functional portable electronics and developing new versatile and flexible electrode materials as alternatives to the materials used in contemporary batteries and supercapacitors is a key challenge. Here, binder-free activated carbon (AC)/carbon nanotube (CNT) paper electrodes for use in advanced supercapacitors have been fabricated based on low-cost, industrial-grade aligned CNTs. By a two-step shearing strategy, aligned CNTs were dispersed into individual long CNTs, and then 90 wt%-99 wt% of AC powder was incorporated into the CNT pulp and the AC/CNT paper electrode was fabricated by deposition on a filter. The specific capacity, rate performance, and power density of the AC/CNT paper electrode were better than the corresponding values for an AC/acetylene black electrode. The capacity reached a maximum value of 267.6 F/g with a CNT loading of 5 wt%, and the energy density and power density were 22.5 W·h/kg and 7.3 kW/kg at a high current density of 20 A/g. The AC/CNT paper electrode also showed a good cycle performance, with 97.5% of the original capacity retained after 5000 cycles at a scan rate of 200 mV/s. This method affords not only a promising paper-like nanocomposite for use in low-cost and flexible supercapacitors, but also a general way of fabricating multi-functional paper-like CNT-based nanocomposites for use in devices such as flexible lithium ion batteries and solar cells.

The China National Health Survey (CNHS) is the first nationwide multi-ethnic cross-sectional interview and health examination conducted from 2012 to 2017. The survey is designed to study reference intervals for physiological constants as well as determinants of noncommunicable diseases among different ethnic populations in different areas, so that the data can be used to enhance clinical diagnosis strategies and health promotion. CNHS used a stratified, multistage cluster sampling method to obtain a sample of 53 895 people aged 20-80 years in 10 ethnic groups from 11 provinces or autonomous regions all over China. Blood samples were collected from each participant for the establishment of the China Multi-Ethnic Biobank (CMEB). CNHS collected data on demographic and socioeconomic information, lifestyle factors, anthropometric measures, laboratory tests and clinical profiles. These data provide a comprehensive resource for further study on risk factors of noncommunicable disease among different ethnic groups. Information about the CNHS database, including publication list, introduction of the survey design and methods, and guidelines for submitting electronic forms of data application, is available at [http://www.bmicc.cn/web/share/home].

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