The Stokes drift of surface waves significantly modifies the upper-ocean turbulence because of the CraikLeibovich vortex force (Langmuir turbulence). Under tropical cyclones the contribution of the surface waves varies significantly depending on complex wind and wave conditions. Therefore, turbulence closure models used in ocean models need to explicitly include the sea state-dependent impacts of the Langmuir turbulence. In this study, the K-profile parameterization (KPP) first-moment turbulence closure model is modified to include the explicit Langmuir turbulence effect, and its performance is tested against equivalent large-eddy simulation (LES) experiments under tropical cyclone conditions. First, the KPP model is retuned to reproduce LES results without Langmuir turbulence to eliminate implicit Langmuir turbulence effects included in the standard KPP model. Next, the Lagrangian currents are used in place of the Eulerian currents in the KPP equations that calculate the bulk Richardson number and the vertical turbulent momentum flux. Finally, an enhancement to the turbulent mixing is introduced as a function of the nondimensional turbulent Langmuir number. The retuned KPP, with the Lagrangian currents replacing the Eulerian currents and the turbulent mixing enhanced, significantly improves prediction of upper-ocean temperature and currents compared to the standard (unmodified) KPP model under tropical cyclones and shows improvements over the standard KPP at constant moderate winds (10 m s 21 ).

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An intriguing aggregation-induced electrochemiluminescence (AIECL) bioconjugate was fabricated by encapsulating fac-tris­(2-phenylpyridine)­iridium­(III) complexes [Ir­(ppy)3] in the apoferritin (apoFt) cavity for biosensing application. Based on the unique pH-dependent disassembly/reassembly characteristic of apoFt, approximately 44.3 molecules of Ir­(ppy)3 aggregated in the single cavity through both intermolecular π–π-stacking interactions and hydrogen bonds that efficiently restricted the intramolecular motions to trigger the AIECL effect. Compared to monomers, Ir­(ppy)3 aggregates performed 5.3-fold-enhanced ECL emission using tri-n-propylamine (TPrA) as a coreactant. The fabricated Ir­(ppy)3@apoFt bioconjugate was flexibly labeled with a detection antibody to act as a transducer for the immunosensor construction. To further catalyze the ECL reaction between the reductive TPrA• and the oxidative Ir­(ppy)3 +• radicals, a conductive and electroactive substrate of Fe2N and gold nanoparticle-codecorated reduced graphene oxide (Fe2N/rGO/Au) was established to incubate the capture antibody. Therefore, a “signal on” immunosensor was developed for sensitive assay of cytokeratin 19 fragment 21–1 (CYFRA 21–1), in which good linearity ranging from 1 pg/mL to 50 ng/mL with a low detection limit of 0.43 pg/mL (S/N = 3) was obtained. This study shares with an inspiration of using apoFt to design iridium­(III)-based AIECL emitters, which will expand more possibilities of organic iridium­(III) complexes in establishing innovative ECL immunoassays.

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Tetracyclines (TCs), including tetracycline (TTC), oxytetracycline (OTC), and chlorotetracycline (CTC), are frequently detected in natural waters, soils, and sediments, which raised great concerns about the proliferation of antibiotic resistant genes. This study investigated the degradation of TCs by sulfate radical produced by thermo-activated persulfate in aqueous solution. Increasing the temperature significantly enhanced the degradation of TTC, and the relationship between pseudo-first-order rate constant (k obs) and temperature obeyed Arrhenius equation. The degradation of TTC showed pH dependency, and k obs increased markedly with increasing pH. Seven intermediate products of TTC were temporarily identified by solid phase extraction and liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS). The transformation pathways of TTC included N-demethylation, hydroxylation-oxidation and dehydration. Detailed mechanisms for sulfate radical-induced N-demethylation and hydroxylation-oxidation were proposed. The degradation of the three TCs followed the order of OTC ＞ CTC ＞ TTC, highlighting the structure-specific reactivity. Interestingly, TTC was degraded extremely fast in artificial surface water (ASW), implying sulfate radical-based oxidation of TCs may be efficient in