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In order to study the corrosion behavior of ER8 wheel steel in coastal neutral chlorine salt environment，the electrochemical corrosion behavior of ER8 wheel steel in neutral NaCl solutions with three different concentrations were analyzed through electrochemical tests， corrosion weight loss tests，scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques.The polarization curve results showed that the self-corrosion current density (Jcorr) was the largest in 5.0%(mass fraction， the same below) NaCl solution at the initial stage of immersion.After immersed for 576 h， Jcorr continued to increase at 2.0%and 3.5%NaCl solutions， and the average corrosion rate was more than 0.12 mm/a for 2 160 h.The SEM results indicated that the morphology of corrosion products were mainly flake and cluster structures.Because the morphology of corrosion products at the initial stage had more pores， it’s difficult to prevent Cl- from reacting with the substrate.The structure of corrosion products was more uniform and denser for 2 160 h.Moreover，the XRD results showed that the corrosion products were mainly composed of γ-FeOOH， α-FeOOH and Fe3O4.

A palladium catalyst system based on PdCl2(PPh3)2 or PdCl2(dppf) is reported for Suzuki‐type coupling of both N‐aryl and alkyl benzotriazinones with aryl/alkenyl boronic acids to afford a series of ortho‐aryl/alkenyl benzamides in yields up to 99%, showing improvements on catalytic efficiency, substrate scope and practicality. Scope and limitations of the improved protocol have been demonstrated with more than 40 examples, including a multigram‐scale synthesis of activated o‐biphenyl amide. Large electronic and steric effects from the boronic acid counterpart have been observed, implying the transmetallation from boron to palladium should be involved in the rate‐determining step in catalytic cycle. [ABSTRACT FROM AUTHOR]

A highly efficient Suzuki coupling of N‐tosyl aryltriazenes with diarylborinic acids or potassium diaryldifluoroborinates is reported under weak basic conditions in aqueous DME or dioxane, respectively. The shelf‐stable and easy‐to‐stoichiometry diaryldifluoroborinates displayed reactivities comparable to the corresponding diarylborinic acids. Scope and limitations of the protocol have been investigated, showing large electronic and steric effects from aryltriazenes. Utility of potassium diaryldifluoroborinates in the Suzuki coupling with activated aryltriazenes provides a cost‐effective and operationally practical access to biaryls from anilines. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Monitoring of sweat pH plays important roles in physiological health, nutritional balance, psychological stress, and sports performance. However, the combination of functional MOFs with phosphorescent material to acquire the real‐time physiological information, as well as the application of dual mode anti‐counterfeiting, has seldom been reported. Herein, we developed multifunctional gel films based on MOFs and phosphorescent dyes which responded to H+ ions and the related mechanism was studied in detail. Upon exposure to H+, the composite gel film exhibited decreased fluorescent signal but enhanced room temperature phosphorescence (RTP), which could be utilized for sweat pH sensing through a dual‐mode. Moreover, multifunctional gel films exhibited a potential application in information encryption and anti‐counterfeiting by designing of stimulus responsive multiple patterns. This research provided a new avenue for portable and non‐invasive sweat pH monitoring methods while also offering insights into stimulus‐responsive multifunctional materials. [ABSTRACT FROM AUTHOR]

Using easily hydrolyzable brominated pyromellitic dianhydride (PMDA) as an electron acceptor, a wide variety of structurally stable binary organic charge‐transfer (CT) microcrystals that are stabilized by dominant intermolecular CT interactions is achieved. By varying the electron‐donating abilities of π‐electron compounds, the resulting single crystalline CT assemblies display tailorable fluorescence emissions spanning from green to near‐infrared. Upon implantation of a π‐electron donor anthracene (An) into fluoranthene‐PMDA (Fl‐PMDA), red and NIR emissions of ternary alloyed assemblies are substantially enhanced due to efficient energy transfer from Fl‐PMDA to An‐PMDA as well as structural complementarity between two CT complexes. Depending on the well‐matched epitaxial relationship, seeded growth of phenanthrene‐PMDA (Ph‐PMDA) onto the pre‐existing An‐PMDA microcrystals is also achieved, leading to core‐shell heterostructures with full and partial coverage. Such an epitaxial growth strategy is also applicable to the construction of microscale heterostructures of diverse CT complex combinations. The ternary Fl1−xAnx‐PMDA alloyed assemblies display composition‐dependent tailorable optical waveguiding behaviors. While An‐PMDA@Ph‐PMDA core‐shell microrods present wavelength‐dependent two‐photon excited fluorescence performances. The rational creation of these homogeneous and heterogeneous CT‐assembled architectures provides us a deep insight to investigate multicomponent functional organic cocrystals. [ABSTRACT FROM AUTHOR]

Chiroptical materials with strong and switchable circularly polarized luminescence (CPL) properties have gained considerable interest due to their feasible applications in optoelectronic devices, sensing, and information encryption. However, in most cases, their luminescence dissymmetry factor (glum) and figure of merit (FOM) values remain very low. Herein, a novel heterogeneous twisted‐stacking structure is proposed, which endows with strong CPL amplification (a maximum of ≈15‐fold enhancement) over traditional homogeneous structures and a high FOM value up to 0.11. Interestingly, their CPL performance (including the sign, magnitude, and spectral position) and the FOM values can be precisely manipulated or even inversed by simply uniaxial stretching, since the phase retardation of the anisotropic poly (vinyl alcohol) layer can be controlled. Moreover, by combining with the viologen gel electrochromic system, the in situ voltage‐driven switching and patterning of the CPL signal can be successfully achieved, with low operation voltage and good cycling stability. This study provides a creative strategy for fabricating strong and electrical switchable CPL‐active materials, which promise new opportunities in miniaturized smart electrochiroptical devices for future information technology. [ABSTRACT FROM AUTHOR]