A Superhydrophobic Dual-Mode Film for Energy-Free Radiative Cooling and Solar Heating.

Traditional electric cooling in summer and coal heating in winter consume a huge amount of energy and lead to a greenhouse effect. Herein, we developed an energy-free dual-mode superhydrophobic film, which consists of a white side with porous coating of styrene-ethylene-butylene-styrene/SiO2 for radiative cooling and a black side with nanocomposite coating of carbon nanotubes/polydimethylsiloxane for solar heating. In the cooling mode with the white side, the film achieved a high sunlight reflection of 94% and a strong long-wave infrared emission of 92% in the range of 8-13 µm to contribute to a temperature drop of ∼11 °C. In the heating mode with the black side, the film achieved a high solar absorption of 98% to induce heating to raise the air temperature beneath by ΔT of ∼35.6 °C. Importantly, both sides of the film are superhydrophobic with a contact angle over 165° and a sliding angle near 0°, showing typical self-cleaning effects, which defend the surfaces from outdoor contamination, thus conducive to long-term cooling and heating. This dual-mode film shows great potential in outdoor applications as coverings for both cooling in hot summer and heating in winter without an energy input.

[Optimization of supercritical fluid extraction of bioactive components in Ligusticum chuanxiong by orthogonal array design].

With the yields of ferulic acid, coniferylferulate, Z-ligustilide, senkyunolide A, butylidenephthalide, butylphthalide, senkyunolide I, senkyunolide H, riligustilide, levistolide A, and total pharmacologically active ingredient as evaluation indexes, the extraction of Ligusticum chuanxiong by supercritical fluid technology was investigated through an orthogonal experiment L9 (3(4)). Four factors, namely temperature, pressure, flow rate of carbon dioxide, co-solvent concentration of the supercritical fluid, were investigated and optimized. Under the optimized conditions, namely 65 degrees C of temperature, 35 MPa of pressure, 1 L x min(-1) of CO2 flow rate, 8% of co-solvent concetration, supercritical fluid extraction could achieve a better yield than the conventional reflux extraction using methanol. And the supercritical fluid extraction process was validated to be stable and reliable.

[Effect of different solvents on extraction of effective components from Ligusticum chuanxiong].

OBJECTIVE: To compare the effect of different solvents such as water, ethanol, methanol, ethyl acetate and petroleum ether on extraction of 10 effective components from Ligusticum chuanxiong and component characteristics of corresponding extracts. METHOD: Ultrasonic assisted solvent extraction and high performance liquid chromatography quantitative analysis were adopted to determine effective components. CAPCELL PAK C18 column (4.6 mm x 150 mm, 5 microm) was adopted. The mobile phase was methanol-0. 5% HAc for gradient elute. The detection wavelength was 280 nm. The column temperature was 30 degrees C. The flow rate was 0. 7 mL x min(-1). The sample size was 10 microL. RESULT: Methanol or ethanol showed no significant difference in extraction of ferulic acid, hydroxyphthalide, alkylphthalide and diligustilide. Ethyl acetate displayed relatively low extraction ratios in hydroxyphthalide and ferulic acid. Water and petroleum ether showed relatively low extraction ratios in all four effective components, and water extracts showed different component characteristics. CONCLUSION: Ethanol and methanol are the most suitable solvents to extract four effective components from L. chuanxiong.