The temperature-dependence of the volume and surface hydrophilicity of a series of water-swollen dense polymer brushes is measured by contact angle measurements in the captive bubble configuration, by ellipsometry, and by quartz crystal microbalance with dissipation monitoring (QCM-D). Thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) and poly(di(methoxyethoxy)ethyl methacrylate) (PMEO2MA), strongly hydrophilic poly(N,N-dimethylacrylamide) (PDMA) and poly(oligo(ethylene glycol) methacrylate) (POEGMA), and weakly hydrophilic poly(2-hydroxyethyl methacrylate) (PHEMA) brushes were synthesized by surface-initiated atom-transfer radical polymerization (SI-ATRP). Conditions leading to reproducible measurements of the contact angle are first provided, giving access to the surface hydrophilicity. Volume hydrophilicity is quantified by measuring the swelling of the brushes, either by QCM-D or by ellipsometry. A model-free methodology is proposed to analyze the QCM-D data. Comparison between the acoustic and optical swelling coefficients shows that QCM-D is sensitive to the maximal thickness of swollen brushes, while ellipsometry provides an integral thickness. Diagrams of surface versus volume hydrophilicity of the brushes finally lead to identify two types of behavior: strongly water-swollen brushes exhibit a progressive decrease of volume hydrophilicity with temperature, while surface hydrophilicity changes moderately; weakly water-swollen brushes have a close-to-constant volume hydrophilicity, while surface hydrophilicity decreases with temperature. Thermoresponsive brushes abruptly switch from one behavior to the other, and do not exhibit an abrupt change of surface hydrophilicity across their collapse transition contrarily to a common erroneous belief. In general, there is no direct correlation between surface and volume hydrophilicity, because surface properties are dependent on the details of conformation and composition at the surface, whereas volume properties are averaged over a finite region within the brush.

Chlorahupetones A-I (1−9), nine sesquiterpenoid dimers, were isolated from Chloranthus henryi var. hupehensis. Their structures were characterized by nuclear magnetic resonance (NMR), electronic circular dichroism (ECD), and X-ray diffraction analysis....

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Lycojaponicumins A-C (1-3), three trace alkaloids isolated from Lycopodium japonicum, represent a unique heterocyclic skeleton formed by the new linkage C4-C9. Notably, lycojaponicumins A and B (1 and 2) are the first examples of natural products possessing a 5/5/5/5/6 pentacyclic ring system with a 1-aza-7-oxabicyclo[2.2.1]heptane moiety. These structures were elucidated by spectroscopic methods and X-ray diffraction analysis. A plausible biogenetic pathway was proposed.

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Comprehensive SummaryIn this study, 27 new sesquiterpenoids: twenty monomers and seven dimers, with diverse structures, along with one known chlorajaponilide F (25) were isolated from the aerial parts of Chloranthus henryi var. hupehensis. Structurally, chlorahupetolides A (1) and B (2), two eudesmane‐type merosesquiterpenoids with an undescribed C18 carbon framework, and chlorahupetene E (18) are the first example of dimers comprising two eudesmane sesquiterpenoids bridged by a four‐membered ring in the Chloranthus. Their structures were characterized by nuclear magnetic resonance (NMR), electronic circular dichroism (ECD), and X‐ray diffraction analysis. In the RAW264.7 macrophages model of inflammation induced by LPS, compounds 12, 18, and 25 significantly reduced NO production in a dose dependent manner and without cytotoxicity. The mRNA expression of COX‐2 was considerably inhibited by treatments with compounds 12, 18, and 25.

Interfacial solar vapor generation has revived the solar-thermal-based desalination due to its high conversion efficiency of solar energy. However, most solar evaporators reported so far suffer from severe salt-clogging problems during solar desalination, leading to performance degradation and structural instability. Here, we demonstrate a free-standing salt-rejecting reduced graphene oxide (rGO) membrane serving as an efficient, stable, and antisalt-fouling solar evaporator. The evaporation rate of the membrane reaches up to 1.27 kg m−2 h−1 (solar–thermal conversion efficiency ∼79%) under one sun, out of 3.5 wt% brine. More strikingly, due to the tailored narrow interlayer spacing, the rGO membrane can effectively reject ions, preventing salt accumulation even for high salinity brine (∼8 wt% concentration). With enabled salt-antifouling capability, flexibility, as well as stability, our rGO membrane serves as a promising solar evaporator for high salinity brine treatment.