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Organic electron‐transport materials (ETMs) play a critical role in enhancing performances and operational stability of organic light‐emitting diodes. In this context, we describe a triazine‐based electron‐transport material in high purity 6‐dphenylphosphinyl‐6′‐(4,6‐(tiphenyl‐1,3,5‐triazin‐2‐yl)[2,2′‐binaphthyl] (DPO‐2Na‐TRZ, MW= 685.75) via arylphosphine oxide modification. It exhibits a glass transition temperature of 130.8 °C. HOMO = −6.03 eV, LUMO = −3.08 eV. Its decomposition occurs at ca. 456 °C at 1% weight loss. Upon 50 wt% Liq doping, DPO‐2Na‐TRZ is investigated as an electron transport layer in bottom‐ and top‐emission green phosphorescent OLEDs. In the presence of an additional exciton‐blocking/electron‐transport layer, the resulting topemission OLED provides attractive characteristics. At a luminance of ca 1000 cd m−2, LE = 91.6 cd A−1, PE = 102.8 lm W−1 and EQE = 22.1 %. Moreover, under continuous driven at a constant current, an extraordinary lifetime t99 > 600 h @ 1000 cd m−2 is observed.

UV-B stress has become one of the main abiotic stress factors threatening crop growth and development, and miR408 plays an important role in plant abiotic stress response. MiR408 is a type of endogenous non-coding small fragment single-stranded RNA, which is mainly found in eukaryotes and participates in the regulation of plant growth and development by responding to various stresses in a manner that negatively regulates the target gene. The effects of photosynthesis and expression levels of miR408-OE rice plants and knockout UCL8 plants under UV-B stress were investigated. The results showed that under UV-B enhanced radiation, the chlorophyll content, intercellular carbon dioxide concentration, net photosynthetic rate and stomatal conductance of the overexpressed miR408 plants were significantly reduced. Under UV-B enhanced radiation, chlorophyll fluorescence kinetic parameters such as Fv/Fm and qP overexpressing miR408 plants were reduced. UV-B significantly inhibited the activity of SOD, POD and CAT in overexpressing miR408 plants and significantly increased their H2O2 and MDA contents. Under UV-B stress treatment, the yield traits such as the number of grains, the number of tillers and the quality of dry matter of overexpressing miR408 plants were significantly reduced. Therefore, UV-B enhances the photosynthetic rate, photosynthetic performance and disruption of the antioxidant system balance of overexpressing miR408 plants, which leads to a decrease in yield. It is speculated that overexpression of miR408 reduced the tolerance of rice to UV-B radiation, that is miR408 may play a negative regulatory role in response to UV-B stress.