A robust artificial solid electrolyte interphase (SEI) film with biomimetic ionic channels and high stability is rationally designed and fabricated by combining the ClO4−‐decorated metal‐organic framework (UiO‐66‐ClO4) and flexible lithiated Nafion binder (Li‐Nafion). The high electronegativity and lithiophilicity of ClO4− groups chemically anchored into the UiO‐66 channels endow the SEI film with an excellent single‐ion conducting pathway, high Li+ transference number, and outstanding ionic conductivity, which can effectively prohibit undesirable reactions of the Li metal with the electrolyte and regulate fast and uniform Li+ flux. With further assistance of the flexible Li‐Nafion binder, the resulting UiO‐66‐ClO4/Li‐Nafion (UCLN) composite film exhibits an excellent mechanical strength to suppress the growth of Li dendrites and maintain the integral stability of the Li metal anodes during cycling. Consequently, the UCLN coated Li metal anodes (Li@UCLN) deliver remarkable cycling stabilities even under a high current density of up to 20 mA cm−2 and large areal capacity of up to 30 mAh cm−2, as well as enhanced rate capacities and cycle lifespans in the full cells even under the harsh conditions for high‐energy density applications.

The secondary alpha deuterium and primary leaving group nitrogen KIEs and Hammett ρ values found for the free ion and ion-pair SN2 reactions between benzyldimethylphenylammonium ion and sodium para-substituted thiophenoxides in methanol at 20.000°C show how (i) ion-pairing of the nucleophile, (ii) a change in substituent in the nucleophile, and (iii) a change in solvent alters the structure of a Type II SN2 transition state. Ion-pairing shortens the weaker sulfur - alpha carbon (S—Cα) transition state bond significantly but does not alter the stronger alpha carbon - leaving group (Cα—N) transition state bond as the bond strength hypothesis predicts. However, the effect of ion pairing, i.e., the decrease in the S—Cα bond on ion-pairing, decreases as a more electron-withdrawing substituent is added to the nucleophile, and the S—Cα bond actually increases when the nucleophile is the p-chlorothiophenoxide ion. The identical Hammett ρ values of -0.85 and -0.84 for the free ion and ion-pair reactions, respectively, may be observed because, on average, the S—Cα bonds are identical in the free ion and ion-pair transition states. When a more electron-donating substituent is added to the nucleophile, an earlier transition state is found in both the ion-pair and free ion reactions. However, the substituent effect is smaller in the ion-pair reactions, presumably because the change in the negative charge on the sulfur atom with substituent is greater in the free ion than in the ion-pair. The substituent effect on transition state structure suggested by the KIEs is not predicted by any of the theories that are used to predict substituent effects on SN2 reactions. Both the secondary alpha deuterium and primary leaving group nitrogen KIEs and the Hammett ρ values indicate that the transition state is earlier when the solvent is changed from DMF to methanol as the "solvation rule for SN2 reactions" predicts. This probably occurs because an earlier, more ionic, transition state is more highly solvated (more stable) in methanol.Key words: nucleophilic substitution, SN2, isotope effect, transition state, substituent, ion-pair.

Electroluminescence (EL) and photoluminescence (PL) spectra of an electron donor, an (poly(N-vinylcarbazole) (PVK))/electron acceptor, and a (2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD)) bi-layer solid film are analysed. The EL emission peak has an apparent red-shift with the increase of driving voltage. There maybe exist an electroplex emission between the PVK and PBD interface under high electric field strength. According to their energy level, the electroplex emission peak should locate at 460 nm. There are great spectra overlapping between PVK emission and electroplex emission, and the ratio of electroplex emission intensity to exciton emission intensity (Ielectroplex/Iexciton) increases from 0.38 at 10 to 0.81 at 16 V. Therefore the measured emission peaks continuously shift from 410 nm at 10 V to 445 nm at 16 V.

This study aims to develop an impedance-based drug screening platform that will help identify drugs that can enhance the vascular barrier function by stabilizing vascular endothelial cell junctions. Methods: Changes in permeability of cultured human retinal microvascular endothelial cells (HRMECs) monolayer were monitored in real-time with the xCELLigence RTCA system. Using this platform, we performed a primary screen of 2100 known drugs and confirmed hits using two additional secondary permeability assays: the transwell permeability assay and the XPerT assay. The cellular and molecular mechanisms of action and in vivo therapeutic efficacy were also assessed. Results: Eleven compounds blocked interleukin 1 beta (IL-1β) induced hyperpermeability in the primary screen. Two of 11 compounds, apigenin and ethaverine hydrochloride, reproducibly blocked multiple cytokines induced hyperpermeability. In addition to HRMEC monolayers, the two compounds stabilized three other types of primary vascular endothelial cell monolayers. Preliminary mechanistic studies suggest that the two compounds stabilize the endothelium by blocking ADP-ribosylation factor 6 (ARF6) activation, which results in enhanced VE-cadherin membrane localization. The two compounds showed in vivo efficacy in an animal model of retinal permeability. Conclusions: We developed an impedance-based cellular phenotypic drug screening platform that can identify drugs that enhance vascular barrier function. We found apigenin and ethaverine hydrochloride stabilize endothelial cell junctions and enhance the vascular barrier by blocking ARF6 activation and increasing VE-cadherin membrane localization. Translational Relevance: The drugs identified from the phenotypic screen would have potential therapeutic efficacy in retinal vascular diseases regardless of the underlying mechanisms that promote vascular leak.

Two cyclometalated iridium(III) complexes have been prepared based on 2-(4-diphenylamino-phenyl)-quinoline and incorporating carboxylic acid ethyl ester (–COOC(2)H(5), (TPAQCE)(2)Irpic and carboxylic acid (–COOH, (TPAQCOOH)(2)Irpic) substituents at the 4-position of the quinoline ligand, respectively. The absorption, emission and (1)H NMR spectra of (TPAQCE)(2)Irpic and (TPAQCOOH)(2)Irpic under alkaline or acidic conditions demonstrate that they respond to the pH of the surrounding solvent environment. The deprotonation of the carboxylic acid group significantly blue-shifts the metal-to-ligand charge transfer absorption band of (TPAQCOOH)(2)Irpic by 48 nm and enhances the emission quantum-yield in DMSO. In addition, (1)H-NMR titration reveals that (TPAQCOOH)(2)Irpic is deprotonated into negatively charged (TPAQCOO(−))(2)Irpic in free DMSO-d(6) solution, and the acid-induced N^O ancillary ligands cleavage or replacement in (TPAQCOOH)(2)Irpic could be ignored. A water-soluble near-neutral optical pH probe (TPAQCOOH)(2)Irpic with pK(a) of ~7 is also reported. In aqueous buffer, (TPAQCOOH)(2)Irpic possesses an obvious emission response with an excellent linearity in the pH range of 6.50–8.00, showing a promising application in bioprocessing.

The chemoenzymatic conversion of cyclohexanone to ε-caprolactone (1.25 M) mediated by immobilized lipase from T. laibacchi was successfully achieved with a yield of 98.6%, which is much higher than that in previous studies. A proposed kinetic model consisting of two enzymatic reactions catalyzed by the lipase and one chemical reaction was developed, which fitted the experimental data very well. It was concluded that the enzymatic oxidation of ethyl acetate using urea hydrogen peroxide (UHP) to generate in situ peracetic acid mediated by the lipase may follow an irreversible ping-pong three–four mechanism with substrate inhibitions, which is proposed herein for the first time. Also, the oxidation of cyclohexanone to ε-caprolactone by peracetic acid in a chemical fashion may follow a power law. Finally, the reaction of formed acetic acid with UHP to form peracetic acid catalyzed by the lipase may follow an irreversible ping-pong Bi–Bi mechanism with substrate inhibitions. Reaction kinetic data reveal that UHP and acetic acid might have strong substrate inhibition, while peracetic acid might have no product inhibition. Results of enzyme stability test suggest that it is reasonable to adopt a simple exponential equation as the inactivation model of the lipase. The effect of Michaelis–Menten interaction on the reaction rate could be neglected due to the strong substrate inhibition, which makes the constant similar to Michaelis–Menten zero. The yield of in situ polymerization was significantly increased from 61.3% to 92.4% under the optimum conditions obtained in this study.

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