The distinct role of extractable and polymeric lipids in plant cuticle, precursors of SOM, has received scarce attention to elucidate plant uptake and soil affinity with organic contaminants. Sorption of naphthalene and 1-naphthol to fruit cuticular fractions isolated from two species were investigated. The polarity index, physical conformation, and glass transition temperature (Tg) of these cuticular fractions were characterized by elemental analysis, Fourier transform infrared spectroscopy, and differential scanning calorimetry, respectively. Cutin, a polymeric lipid, is the major sorption medium of the cuticle due to its large mass fraction and liquid-like nature (Tg approximately -30 degrees C). Sorption of cutin is suppressed by the extractable lipids (wax, Tg approximately 44 degrees C) acting as an antiplasticizer (enhance cutin's Tg) over nonpolar contributor. Whereas polysaccharide, as a plasticizer (lower Tg value) and polar contributor, regulates affinity of polymeric lipids (cutin and cutan). The contribution of cutin to sorption by bulk cuticle overshadows the role of waxes, and the sorption capability (K(oc)) of cutin overwhelms the octanol-water partition coefficient (K(ow)). Therefore, uptake of organic contaminants by these plants would be seriously under-predicted by their extractable lipid content and compound's K(ow) values. Along with the observed linear relationships of K(oc) with cutin content in these cuticular fractions, we suggest for the first time that the depolymerizable lipid fraction (cutin) is required to accurately predict plant accumulation of organic contaminants.

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Organic near‐infrared (NIR) detectors have potential applications in biomedicine, agriculture, and manufacturing industries to identify and quantify materials contactless, in real time and at a low cost. Recently, tunable narrow‐band NIR sensors based on charge‐transfer state absorption of bulk‐heterojunctions embedded into Fabry‐Pérot micro‐cavities have been demonstrated. In this work, this type of sensor is further miniaturized by stacking two sub‐cavities on top of each other. The resulting three‐terminal device detects and distinguishes photons at two specific wavelengths. By varying the thickness of each sub‐cavity, the detection ranges of the two sub‐sensors are tuned independently between 790 and 1180, and 1020 and 1435 nm, respectively, with full‐width‐at‐half‐maxima ranging between 35 and 61 nm. Transfer matrix modeling is employed to select and optimize device architectures with a suppressed cross‐talk in the coupled resonator system formed by the sub‐cavities, and thus to allow for two distinct resonances. These stacked photodetectors pave the way for highly integrated, bi‐signal spectroscopy tunable over a broad NIR range. To demonstrate the application potential, the stacked dual sensor is used to determine the ethanol concentration in a water solution.

Organic light-emitting diodes (OLEDs) suffer from notorious light trapping, resulting in only moderate external quantum efficiencies. Here, we report a facile, scalable, lithography-free method to generate controllable nanostructures with directional randomness and dimensional order, significantly boosting the efficiency of white OLEDs. Mechanical deformations form on the surface of poly(dimethylsiloxane) in response to compressive stress release, initialized by reactive ions etching with periodicity and depth distribution ranging from dozens of nanometers to micrometers. We demonstrate the possibility of independently tuning the average depth and the dominant periodicity. Integrating these nanostructures into a two-unit tandem white organic light-emitting diode, a maximum external quantum efficiency of 76.3% and a luminous efficacy of 95.7 lm W −1 are achieved with extracted substrate modes. The enhancement factor of 1.53 ± 0.12 at 10,000 cd m −2 is obtained. An optical model is built by considering the dipole orientation, emitting wavelength, and the dipole position on the sinusoidal nanotexture.