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Solid-liquid triboelectric nanogenerators (SL-TENGs) have shown promising prospects in energy harvesting and application from water resources. However, the low contact separation speed, small contact area, and long contacting time during solid-liquid electrification severely limit their output properties and further applications. Here, by leveraging the rheological properties of gas-liquid two-phase flow and the Venturi-like design, we circumvent these limitations and develop a previously unknown gas-liquid two-phase flow-based TENG (GL-TENG) that can achieve ultrahigh voltage and volumetric charge density of 3789 volts and 859 millicoulombs per cubic meter, respectively. With a high-power output of 143.6 kilowatts per cubic meter, a 24-watt commercial lamp can be directly lighted by a continuous-flow GL-TENG device. The high performance displayed SL-TENGs in this work provides a promising strategy for the practical application of solid-liquid TENGs in energy harvesting and sensing applications.

Flexible and wearable energy storage microdevice systems with high performance and safety are promising candidates for the electronics of on-chip integration. Herein, we demonstrate inkjet-printed ultrathin electrodes based on molybdenum disulfide (MoS 2 ) nanosheets for flexible and all-solid-state in-plane microsupercapacitors (MSCs) with high capacitance. The MoS 2 nanosheets were uniformly dispersed in the low-boiling point and nontoxic solvent isopropanol to form highly concentrated inks suitable for inkjet printing. The MSCs were assembled by printing the highly concentrated MoS 2 inks on a polyimide substrate with appropriate surface tension using a simple and low-cost desktop inkjet printer. Because of the twodimensional structure of MoS 2 nanosheets, the as-assembled planar MSCs have high loadings of active materials per unit area, resulting in more flexibility and thinness than the capacitors with a traditional sandwich structure. These planar MSCs can not only possess any collapsible shape through the computer design but also exhibit excellent electrochemical performance (with a maximum energy density of 0.215 mW h cm −3 and a high-power energy density of 0.079 W cm −3 ), outstanding mechanical flexibility (almost no degradation of capacitance at different bending radii), good cycle stability (85.6% capacitance retention even after 10,000 charge−discharge cycles), and easy scale-up. Moreover, a blue light-emitting diode can be powered using five MSCs connected in series. The in-plane and low-cost MSCs with high energy densities have great application potential for integrated energy storage systems including wearable planar solar cells and other electronics.

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Gas sensors based on reduced graphene oxide (rGO) films and rGO/MoS hybrid films were fabricated on polyethylene naphthalate substrates by a simple self-assembly method, which yielded flexible devices for detection of formaldehyde (HCHO) at room temperature. The sensing test results indicated that the rGO and rGO/MoS sensors were highly sensitive and fully recoverable to a ppm-level of HCHO. The bending and fatigue test results revealed that the sensors were also mechanically robust, durable and effective for long-term use. The rGO/MoS sensors showed higher sensitivities than rGO sensors, which was attributed to the enhanced HCHO adsorption and electron transfer mediated by MoS. Furthermore, two kinds of MoS nanosheets were prepared by either hydrothermal synthesis or chemical exfoliation and were compared for their detection of HCHO, which revealed that the hydrothermally produced MoS nanosheets with rich defects led to enhanced sensitivity of the rGO/MoS sensors. Moreover, these fabricated flexible sensors can be applied for the HCHO detection in food packaging.

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Shade shelter is widely used to reduce heat load for farm animals, but little research focus on the cooling effects for Dehong buffalo calves. The aim of this experiment was to evaluate the impacts of shade cooling on the physiological and behavioural parameters for Dehong buffalo calves. Shade with 99% blockage of solar radiation was covered on steel frame with a 2.5 m height above the loafing area floor (Shaded). The loafing area of the control group was the same as the shaded group, © 2016. This manuscript version is made available under the Elsevier user license http://www.elsevier.com/open-access/userlicense/1.0/ apart from no shade shelter above the loafing area (non-shaded). Twenty-four Dehong buffalo calves were randomly and averagely allocated to the non-shaded and shaded groups. Six Dehong buffalo calves were loose housed in a barn, and they had access to loafing area. The results showed that the average daily air temperature of the loafing area under shade was lower 1.5 than that of the non-shaded loafing area. No difference in rectal temperature was found between the non-shaded and shaded calves (P > 0.05), but respiration rate of the non-shaded group in noon (12:00h, 31.6 breaths) and evening (18:00h, 28.5 breaths) was greater than for calves in shaded group (26.1 and 25.3 breaths, respectively) (P < 0.05). When ambient temperature exceeded 30 , shaded calves spent much of their time (21.7%) lying in the loafing area, and no calf in non-shaded group preferred to lie in the loafing area with strong solar radiation (P < 0.05). The use of shade for calves was affected by thermal environment, and the use of shade was greater (41.4%) in hot weather (above 30 ) than that of the warm weather (22-29 ) (P < 0.05). In conclusion, the provision of shade above the loafing area is conducive to improving thermal environment for Dehong buffalo calves in subtropical area characterized with high ambient temperature coupled with high humidity in summer.

Lithium iron phosphate (LiFePO4) is widely applied as the cathode material for the energy storage Li‐ion batteries due to its low cost and high cycling stability. However, the low theoretical specific capacity of LiFePO4 makes its initial capacity loss more concerning. Therefore, lithium compensation by way of prelithiation and applications of sacrificial Li‐rich additives in LiFePO4 is imminent in elevating the energy density and/or prolonging the lifetime of the LiFePO4‐based Li‐ion batteries (LIBs). Prelithiation in LiFePO4 is herein carried out by electrochemical and chemical methods and its feasibility is proved on the basis of the electrochemical evaluations such as the initial charge capacity and the cycling stability. In addition, the site of the pre‐intercalated Li‐ions is found via comprehensive physical characterizations and the density functional theory (DFT) calculations. These findings open a new avenue for elevating the energy density and/or prolonging the lifetime of the high‐energy‐density batteries.