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The multi-scale composite porous wick (MCPW) was fabricated with alloying-dealloying mehtod for the application in the two-phase heat transfer device. The nanostructures were constructed on the sintered copper powders, resulting in the change of surface topography and wettability for MCPW. The capillary rise test was conducted to study the capillary performance based on the IR thermal imaging method. In this study, the comparisons of the two kinds of copper powders and two types of corrosive solutions were conducted to explore porous structure effects and the interactions between the microstructures and nanostructures. Three different working liquids, i.e., acetone, ethanol and water were performed and compared on the MCPW and sintered wick. Test results showed that the MCPW presented hydrophilic performance, facilitating the penetration of the working fluid into the pores. Capillary performance could be significantly enhanced owing to the nanostructures, especially for the sample sintered with irregular copper powder and deallyed by NaOH solution.

The novel triphenylene derivatives with one, two or three diphenylacrylonitrile groups on the side chain were prepared in yields of 75–83%. The influence of the number of diphenylacrylonitrile groups on the mesophase and fluorescence properties were investigated. The triphenylene derivatives with one or two diphenylacrylonitrile groups exhibited not only the ordered hexagonal columnar mesophase but also good AIE fluorescence properties in both solution and solid state.

The first near-infrared fluorescent and columnar liquid crystal based on Bodipy was achieved by modifying 3,5-alkenyl substituted Bodipy with two triphenylene units. Triphenylene-Bodipy-triphenylene triad with 3,5-alkenyl groups exhibited hexagonal columnar mesophase and near-infrared fluorescence at 650–800 nm with the quantum yield of 31%.

Four novel triphenylene-Bodipy dyads were synthesized in yields of 32–38% and characterized by MS, NMR, elemental analysis. They exhibit good columnar liquid crystal behaviors at room temperature. The alkyl substitution on the Bodipy unit does not cause the disruption of the mesophase. They possess excellent fluorescence properties with high quantum yields in solution and the weak fluorescence in film. The alkyl substitutions on the Bodipy unit increase the fluorescence intensity and the introduction of triphenylene units reduce the aggregation-caused quenching of orderly stacking of Bodipy units.

Two novel gallic trimer 7 and tetramer 8 based on acylhydrazone structures were designed and synthesized in yields 76% and 81%, respectively. Their structures were confirmed by 1H NMR, ESI-MS, and elemental analysis. Their mesomorphic properties were investigated by DSC, POM, and XRD analyses. The mesomorphic results suggested that they possessed good room-temperature columnar liquid crystalline property with wide range of mesomorphic temperature. The ranges of mesomorphic temperatures for compounds 7 and 8 were as wide as 115°C and 124°C, respectively.

By the Schiff-base condensation of formacyl calix[4]crown(2) with raw chitosan, a novel calix[4]crown-grafted chitosan chelating polymer(3) was conveniently prepared in good yield. The structure of polymer 3 was confirmed by elemental analysis, infrared(IR) spectrometry and X-ray diffraction(XRD) analysis. The elemental analysis suggests that the grafting degree of calixcrown unit was 22% on the amino groups of chitosan. The morphological characteristic of polymer 3 was studied by scanning electron microscopy(SEM). Polymer 3 possessed loose porous and smooth morphology of surface. The dyes adsorption abilities of polymer 3 for a series of organic dyes[Orange I(OI), Neutral red(NR), Victoria blue B(VB) and Brilliant green(BG)] were studied by solid-liquid adsorption experiments. The adsorption percentages increased from 45%―60%(raw chitosan for dyes) to 75%―90%(polymer 3 for dyes). The highest adsorption percentage reached 89% for VB. The saturated adsorption capacities for OI, NR, VB and BG were as high as 622, 564, 854 and 781 mg/g, respectively. The adsorption abilities kept stable at 70%―90% in the scope of pH=5―9. The adsorption abilities for anionic dye(OI) decreased gradually with the increase of pH and the opposite trend was observed for cationic dyes(NR, BG, VB). The adsorption percentages were 70%―90% after five times’ cycles for adsorption.

Fluid motion control has always been essential in electrowetting devices. Using the inkjet printing technique, an organic-inorganic hybrid material, polytitanosiloxane, was patterned as a secondary dielectric under the hydrophobic fluoropolymer coating in an optical electrowetting device (OEWD). The effects of different structural parameters of the inkjet-printed polytitanosiloxane (IPP) layer on both the fluid motion at the microscopic level and the macroscopic visual performances of the device were studied experimentally. The leakage-current test was also performed to evaluate the insulating performance of the composite dielectric layer. In addition, COMSOL Multiphysics was used to simulate the fluid flow inside the OEWD with/without the polytitanosiloxane layer. The results showed that, by introducing this IPP layer, precise fluid motion control and improved performance could be obtained.

Three novel gallic-calixarene derivatives 5, 6 and 7 were prepared in yields of 57–76%. Their structures and conformations were confirmed by element analyses, IR, ESI-MS and NMR spectra. Compounds 5 and 6 with stable cone conformation show liquid crystalline behaviours but compound 7 with no stable conformation exhibits no mesophase. These results indicated that the stable cone conformation plays a crucial role for mesomorphic property.

The gallic–cyanuric monomer 4, gallic–cyanuric dimer 5, gallic–cyanuric trimer 6 and gallic–cyanuric tetramer 7 containing multiple hydrogen bond were designed and synthesized in yields of 70–80%. Their symmetric structures were characterized by element analyses, FT-IR, ESI-MS, and NMR spectra. Their hexagonal columnar liquid crystalline phases were confirmed by DSC, POM, and XRD analyses. The scope of mesomorphic temperature of compounds 5, 6, and 7 is as wide as 45.7, 70.1, and 134.4 °C, respectively. The more gallic ether units are favorable for excellent mesophase.

Marine chromophoric dissolved organic matter (CDOM) and its related fluorescent components (FDOM), which are widely distributed but highly photobleached in the surface ocean, are critical in regulating light attenuation in the ocean. However, the origins of marine FDOM are still under investigation. Here we show that cultured picocyanobacteria, Synechococcus and Prochlorococcus, release FDOM that closely match the typical fluorescent signals found in oceanic environments. Picocyanobacterial FDOM also shows comparable apparent fluorescent quantum yields and undergoes similar photo-degradation behaviour when compared with deep-ocean FDOM, further strengthening the similarity between them. Ultrahigh-resolution mass spectrometry (MS) and nuclear magnetic resonance spectroscopy reveal abundant nitrogen-containing compounds in Synechococcus DOM, which may originate from degradation products of the fluorescent phycobilin pigments. Given the importance of picocyanobacteria in the global carbon cycle, our results indicate that picocyanobacteria are likely to be important sources of marine autochthonous FDOM, which may accumulate in the deep ocean., The sources of marine chromophoric dissolved organic matter and associated fluorescent DOM (FDOM) remain unclear. Here, the authors demonstrate that picocyanobacteria release FDOM similar to typical fluorescent signals found in the ocean, and are likely to be an important source of marine FDOM.

Three novel gallic monomer 7, dimer 10 and trimer 12 with conjugated cyanuric core were designed and synthesised by Schiff-base condensation mode in yields of 80–90%. Their structures were characterised by fourier transform infrared spectroscopy, 1H NMR (nuclear magnetic resonance), electrospray ionization mass spectrometry and elemental analyses. Their mesomorphic behaviours were investigated by differential scanning calorimetry, polarising optical microscopy and X-ray diffraction. The gallic monomer 7 has no mesomorphic property, but the dimer 10 and trimer 12 possess good mesomorphic properties. The trimer 12 with high symmetry exhibited the typical hexagonal columnar liquid crystal at room temperature. The temperature range of mesophase is as wide as 149°C (14–163°C). The results suggested that the more gallic units and symmetric structures are favourable for excellent mesomorphic properties.