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Histone deacetylase 6 (HDAC6) plays a key role in a variety of neurological disorders, which makes it attractive drug target for the treatment of Alzheimer’s disease, Parkinson’s disease, and memory/learning impairment. The selectivity of HDAC6 inhibitors (sHDAC6Is) are widely considered to be susceptible to the sizes of their Cap group and the physicochemical properties of their linker or zinc-binding group, which makes the discovery of new sHDAC6Is extremely difficult. With the discovery of the distinct selectivity between Trichostatin A (TSA) enantiomers, the chirality residing in the connective units between TSA’s Cap and linker shows a great impact on its selectivity. However, the mechanism underlining (S)-TSA’s selectivity is still elusive, and the way chirality switches the selective (S)-TSA to nonselective (R)-TSA is unknown. In this study, multiple computational approaches were collectively applied to explore, validate, and differentiate the binding modes of two TSA enantiomers in HDACs (especially the HDAC6) at atomic level. First, two nonconservative residues (G200/M205 and Y197/F202 in HDAC1/6) in loop3 and four conservative residues deep inside the hydrophobic binding pocket were discovered as the decisive residues of (S)-TSA’s selectivity toward HDAC6. Then, a novel mechanism underlying the selectivity of (S)-TSA toward HDAC6 was proposed, which was composed of the trigger by two nonconservative residues F202 and M205 in HDAC6 and a subsequently improved fit of (S)-TSA deep inside HDAC6’s hydrophobic binding pocket. TSA enantiomers were used as a molecular probe to explore the mechanism underlying sHDAC6Is’ selectivity in this study. Because of their decisive roles in (S)-TSA’s selectivity to HDAC6, both F202 and M205 in HDAC6 should be especially considered in the discovery of novel sHDAC6Is.

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Integrating the battery behavior and supercapacitor behavior in a single electrode to obtain better electrochemical performance has been widely researched. However, there is still a lack of research studies on an integrated battery−capacitor supercapacitor electrode (BatCap electrode). In this work, an integrated BatCap electrode porous carbon-coated Mn−Ni-layered double oxide (Mn−Ni LDO-C) was fabricated successfully using controllable heat treatment of polypyrrole-precoated Mn−Ni-layered double hydroxide (Mn−Ni LDH@PPy). This Mn−Ni LDO-C electrode was grown on Ni foam directly and possessed a hierarchical structure that consisted of a pyridinic N (N-6)-doped porous carbon shell and a Mn−Ni LDO core within abundant oxygen vacancies. Benefiting from the synergistic effect of N-6-doped porous carbon and increased oxygen vacancies, Mn−Ni LDO-C exhibited excellent electrochemical performance. The capacity of Mn−Ni LDO-C reached 2.36 C cm −2 (1478.1 C g −1 ) at 1 mA cm −2 and remained at 92.1% of the initial capacity after 5000 cycles at a current density of 20 mA cm −2 . The aqueous battery−supercapacitor hybrid device Mn−Ni LDO-C//active carbon (Mn−Ni LDO-C//AC) also presented superior cycle stability: it retained 85.3% of the original capacity after 5000 cycles at 2 A g −1 . Meanwhile, Mn−Ni LDO-C//AC could work normally under a wider potential window (2.0 V), so that the device held the highest energy density of 78.2 Wh kg −1 at a power density of 499.7 W kg −1 and retained 39.1 Wh kg −1 at the highest power density of 31.3 kW kg −1 . Two Mn−Ni LDO-C//AC devices connected in series could light a light-emitting diode (LED) bulb easily and keep the LED brightly illuminated for more than 10 min. In general, this work synthesized an integrated BatCap electrode Mn−Ni LDO-C; the integrated electrode exhibited high electrochemical performance, thus has a promising application prospect in the field of energy storage.

Anodic oxidation treatment of commercially pure titanium was carried out at the voltages of 10, 30, 50 V in 0.5 M H2SO4 solution at the potentiodynamic-aging mode so as to obtain the effects of the anodic potential on the surface characteristic and corrosion resistance of the anodic oxide film. The influences of potential on the surface morphology, the roughness, the crystalline behavior, the chemical composition and the corrosion resistance of the anodic oxide films were investigated by using scanning electron microscopy (SEM), atomic force microscope (AFM), Raman spectrum, X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), potentiodynamic polarization curves and electrode impedance spectroscopy (EIS). The results show that increasing anodic potential at the potentiodynamic-aging mode can significantly enhance thickness, flatness, crystallization, chemical stability, and corrosion resistance of anodic oxide film.