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Mesoproterozoic (ca. 1.3 Ga) magmatism in the North China Craton (NCC) was dominated by mafic intrusions (dolerite sills) with lesser amounts of granitic magmatism, but our lack of knowledge of this magmatism hinders our understanding of the evolution of the NCC during this period. This study investigated porphyritic granites from the Huade–Kangbao area on the northern margin of the NCC. Zircon dating indicates the porphyritic granites were intruded during the Mesoproterozoic between 1285.4 ± 2.6 and 1278.6 ± 6.1 Ma. The granites have high silica contents (SiO2 = 63.10–73.73 wt.%), exhibit alkali enrichment (total alkalis = 7.71–8.79 wt.%), are peraluminous, and can be classified as weakly peraluminous A2-type granites. The granites have negative Eu anomalies (δEu = 0.14–0.44), enrichments in large-ion lithophile elements (LILEs; e.g., K, Rb, Th, and U), and depletions in high-field-strength elements (HFSEs; e.g., Nb, Ta, and Ti). εHf(t) values range from –6.43 to +2.41, with tDM2 ages of 1905–2462 Ma, suggesting the magmas were derived by partial melting of ancient crustal material. The geochronological and geochemical data, and regional geological features, indicate the Mesoproterozoic porphyritic granites from the northern margin of the NCC formed in an intraplate tectonic setting during continental extension and rifting, which represents the response of the NCC to the break-up of the Columbia supercontinent. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1. A novel SO 2 fluorescent probe B3 was synthesized. • 2. B3 can respond to SO 2 within 9 s. • 3. A high-throughput method for detecting SO 2 in food was established. • 4. B3 successfully applied to detection of SO 2 in food. Sulfur dioxide (SO 2), widely used as an antioxidant and preservative in food production, has been associated with detrimental cardiovascular and neurological effects when consumed excessively. This highlights the pressing need to develop a fast and sensitive probe capable of high-throughput screening for the quantitative determination of SO 2 in food. Herein, we synthesized a new fluorescent probe, namely B3 , specifically designed for high-throughput detection of SO 2 in food. The vinyl chloride aldehyde within the B3 structure engages in a nucleophilic addition reaction with SO 2 , contributing to B3 ′s exceptional selectivity for SO 2 , and fast response time within 9 s. Furthermore, by integrating B3 with a microplate reader, we effectively achieved high-throughput detection of SO 2 concentration up to 45 μM within a pH range of 5.5 to 8.0 in real food samples. This accomplishment serves as a significant contribution to ensuring consumer safety and facilitating health assessments. [ABSTRACT FROM AUTHOR]

Although sensitizing traditional fluorescent dyes with thermally activated delayed fluorescence (TADF) exciplexes has been extensively studied, the device performance of solution‐processed organic light‐emitting diodes (OLEDs) still lags far behind in this regard. Herein, the novel exciplex with high up‐conversion efficiency composed of a triazatruxene‐based donor and a triazine‐based acceptor is employed as a TADF sensitizer to fluorescent dye in solution‐processed hyperfluorescent OLEDs. Benefiting from the small activation energy for triplet up‐conversion and less non‐radiative recombination of triplet excitons, the new TADF exciplex can up‐convert efficiently non‐radiative triplet excitons through reverse intersystem crossing. Besides, expeditious up‐conversion processes also shorten the residence time of triplet excitons, giving rise to significant suppression of detrimental Dexter energy transfer from the exciplex sensitizer to the dopant. By maximizing the triplet up‐conversion efficiency of exciplex sensitizers, the optimized OLEDs achieve a maximum external quantum efficiency (EQEmax) of 16.0%, which is the first report for the solution‐processed exciplex‐sensitized hyperfluorescent OLEDs with EQEmax exceeding 15%. These results validate that the up‐conversion efficiency of triplet excitons in the exciplexes strongly affects the performance of exciplex‐sensitized fluorescent devices, and the triazatruxene‐based molecules are promising donor candidates for constructing the exciplexes with high up‐conversion efficiency. [ABSTRACT FROM AUTHOR]

Phosphorescent manganese(II) complexes with high photoluminescence quantum yields (PLQYs) and low cost exhibit great potential in organic light‐emitting diodes (OLEDs), information security, and X‐ray imaging. However, it is still a challenge to tune their emission colors. Herein, an effective strategy for engineering the phosphorescence colors of tetrahedral Mn(II) complexes through steric hindrance‐driven bond angle distortion is proposed. Modulating the steric hindrance between phosphine and benzofuran and varying the O─Mn─O bond angles allows these Mn(II) complexes to emit from 498 to 548 nm. Interestingly, these achiral single crystals of Mn(II) complexes exhibit significant circularly polarized luminescence signals due to symmetry breaking. Furthermore, high‐performance green OLEDs are achieved by using these Mn(II) complexes as dopants, providing a record‐high external quantum efficiency of 15.7%. These super‐duper results greatly inspire the development of multi‐color Mn(II) complexes and low‐cost Mn‐based devices. [ABSTRACT FROM AUTHOR]

Solution processable transparent top electrodes with good conductivity and high transmittance play a critical role in developing highly efficient semitransparent organic solar cells (ST-OSCs). Herein, a simple low-temperature spray-coating method is proposed to fabricate silver nanowires/zinc oxide nanoparticles (AgNWs/ZnO) composite electrodes. The effects of coverage of ZnO nanoparticles on optoelectronic properties and surface morphologies of the composites are systemically investigated. Compared to the pristine AgNWs, the AgNWs/ZnO composite layer exhibits improved electrical conductivity due to the filling of nanoparticles as well as the capillary force caused during the volatilization of ZnO dispersion. A low sheet resistance of 8.3 Ω/ and a high transmittance of 78.91 % at 550 nm are achieved in the optimized AgNWs/ZnO composite films with excellent thermal and mechanical stabilities. By using the spray-coated AgNWs composite as the top electrode, the PM6:N3 based ST-OSCs prepared on ITO/glass substrate attain a power conversion efficiency (PCE) of 10.88 % and an average transmittance (AVT) of 28.80 % due to the enhanced charge extraction and suppressed trap-assisted recombination. Moreover, fully solution-processed ST-OSCs are fabricated based on AgNWs/ZnO top electrodes, achieving a PCE of 9.01 % and an AVT of 27.8 %. It provides a simple and effective strategy to fabricate transparent flexible top electrodes and may pave the way towards all-solution-processed highly efficient ST-OSCs. • A simple low-temperature spray-coating method is proposed to fabricate AgNWs/ZnO top electrodes. • The coverage of ZnO improves both conductivity and morphology of the composites. • The resultant devices show enhanced charge extraction and suppressed recombination. • All-solution-processed flexible ST-OSCs achieve a PCE of 9.0 % and AVT of 27.8 %. [ABSTRACT FROM AUTHOR]