Transporting water and oil microdroplets is important for applications ranging from water harvesting to biomedical analysis but remains a great challenge. This is due to the amplified contact angle hysteresis and insufficient driving force in the micrometer scale, especially for low-surface energy oil droplets. Coalescence of neighboring droplets, which releases vast additional surface energy, was often required, but its relatively uncontrollable nature brings uncertainties to the droplet motion, and the methodology is not applicable to single droplets. Here we introduce a strategy based on slippery surface with immobilized lubricant menisci to directionally transport microdroplets. By simply mounting hydrogel dots on slippery surface, the raised menisci remotely pump microdroplets via capillary force with high efficiency, regardless of droplet size or surface energy. By proof-of-concept experiments, we demonstrate that our method allows for highly efficient water droplet collection and highly sensitive biomedical analyte detection.droplet transport | microdroplet | capillary force | slippery surface | antifouling

MOF/COF-based hybrids show the properties of precisely tunable compositions and structures, and provide a broad range of potential applications in gas sorption and separation, catalysis, energy transfer, biomedicine, etc.

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A binary solvent of ethyl acetate and n‐heptane was made and applied together with ionic liquids (ILs, 1‐ethyl‐3‐methyl imidazolium tetrafluoroborate ([Emim]BF4)) to extract bitumen from oil sands at ambient conditions. Results of bottle tests show that the bitumen recovery is highly dependent on the volume ratio of ethyl acetate to n‐heptane. The maximum recovery was obtained at the ethyl acetate‐to‐n‐heptane ratio of 3:6. With external addition of ILs, an additional improvement of ∼10 % of bitumen recovery was observed (from 83 to 93 % at the ethyl acetate‐to‐n‐heptane ratio of 3:6). Based on the intensive investigation of key operational parameters (i.e. ILs‐to‐solvent ratio, agitation time, and conditioning time), a set of recommended extraction conditions were proposed to maximize the bitumen recovery. Further fractionation of the extracted bitumen together with FTIR and SEM detection on the residual solids indicated that ILs addition could increase the dissolution of bitumen fractions into solvents, while reducing the entrapment of fine particles in the solvents. The improvement of bitumen recovery by ILs addition was attributed to the enhancement of the liberation of bitumen components from mineral solids surfaces during oil sands solvent extraction. However, the asphaltenes were observed to be rejected during processing due to their accumulation at the oil‐ILs interface as a film.

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The vector vortex beams (VVB) possessing non-separable states of light, in which polarization and orbital angular momentum (OAM) are coupled, have attracted more and more attentions in science and technology, due to the unique nature of the light field. However, atmospheric transmission distortion is a recurring challenge hampering the practical application, such as communication and imaging. In this work, we built a deep learning based adaptive optics system to compensate the turbulence aberrations of the vector vortex mode in terms of phase distribution and mode purity. A turbulence aberration correction convolutional neural network (TACCNN) model, which can learn the mapping relationship of intensity profile of the distorted vector vortex modes and the turbulence phase generated by first 20 Zernike modes, is well designed. After supervised learning plentiful experimental samples, the TACCNN model compensates turbulence aberration for VVB quickly and accurately. For the first time, experimental results show that through correction, the mode purity of the distorted VVB improves from 19% to 70% under the turbulence strength of D/r0 = 5.28 with correction time 100 ms. Furthermore, both spatial modes and the light intensity distribution can be well compensated in different atmospheric turbulence.

A Ni-20Cr alloy and variants containing 5, 10 and 20Cu (all in wt.%) were carburised in H 2 -5% CH 4 at 1,000°C. All alloys formed internal carburisation zones containing Cr 3 C 2 and Cr 7 C 3 . The Ni-20Cr alloy also developed a surface deposit of graphite, but the copper-bearing alloys did not. Measured parabolic rate constants for intragranular carburisation were used to calculate carbon permeabilities from Wagner's diffusion analysis. The value obtained for Ni-20Cr was in good agreement with the product of independently measured carbon solubility and diffusion coefficient values for nickel. Permeabilities found for copper-bearing alloys were similar, showing that the presence of copper had little effect on carbon diffusion in nickel. This finding is used in analysing the mechanism by which nickel undergoes metal dusting.