Defensins knowledgebase: a manually curated database and information source focused on the defensins family of antimicrobial peptides

The defensins knowledgebase is a manually curated database and information source focused on the defensin family of antimicrobial peptides. The current version of the database holds a comprehensive collection of over 350 defensin records each containing sequence, structure and activity information. A web-based interface provides access to the information and allows for text-based searching on the data fields. In addition, the website presents information on patents, grants, research laboratories and scientists, clinical studies and commercial entities pertaining to defensins. With the rapidly increasing interest in defensins, we hope that the knowledgebase will prove to be a valuable resource in the field of antimicrobial peptide research. The defensins knowledgebase is available at

Mass Transfer and Droplet Behaviors in Liquid-Liquid Extraction Process Based on Multi-Scale Perspective: A Review

Liquid-liquid extraction is an important separation technology in the chemical industry, and its separation efficiency depends on thermodynamics (two-phase equilibrium), hydrodynamics (two-phase mixing and contact), and mass transfer (molecular diffusion). For hydrodynamics, the dispersion size of droplets reflects the mixing of two phases and determines the mass transfer contact area of the two phases. Therefore, a deep understanding of the droplet dispersion mechanism can help guide process intensification. The mass transfer and droplet behaviors in the liquid-liquid extraction process are reviewed based on three scales: equipment, droplets, and the interface between two liquids. Studies on the interaction between mass transfer and other performance parameters in extraction equipment as well as liquid-liquid two-phase flow models are reviewed at the equipment scale. The behaviors of droplet breakage and coalescence and the kernel function of the population balance equation are reviewed at the droplet scale. Studies on dynamic interfacial tension and interaction between interfaces are reviewed at the interface scale. Finally, the connection among each scale is summarized, the existing problems are analyzed, and some future research directions are proposed in the last section

Synthesis, Structures, and Reactivity of Single and Double Cyclometalated Complexes Formed by Reactions of [Cp*MCl₂]₂ (M = Ir and Rh) with Dinaphthyl Phosphines

Reactions of two dinaphthyl phosphines with [Cp*IrCl₂]₂ have been carried out. In the case of di­(α-naphthyl)­phenylphosphine (<b>1a</b>), a simple P-coordinated neutral adduct <b>2a</b> is obtained. However, <i>tert</i>-butyldi­(α-naphthyl)­phenylphosphine (<b>1b</b>) is cyclometalated to form [Cp*IrCl­(P^C)] (<b>3b</b>). Complexes <b>2a</b> and <b>3a</b> undergo further cyclometalation to give the corresponding double cyclometalated complexes [Cp*Ir­(C^P^C)] (<b>4a</b>,<b>b</b>) upon heating. In the presence of sodium acetate, reactions of <b>1a</b>,<b>b</b> with [Cp*IrCl₂]₂ directly afford the final double cyclometalated complexes (<b>4a</b>,<b>b</b>). In the absence of acetate, [Cp*RhCl₂]₂ shows no reaction with <b>1a</b>,<b>b</b>, whereas with acetate the reactions form the corresponding single cyclometalated complexes [Cp*RhCl­(P^C)] (<b>5a</b>,<b>b</b>), which react with ^<i>t</i>BuOK to form the corresponding rhodium hydride complexes (<b>6a</b>,<b>b</b>). Treatment of <b>4a</b> with CuCl₂ or I₂ leads to opening of two Ir–C σ bonds to yield the corresponding P-coordinated iridium dihalide (<b>7</b> or <b>8</b>) by means of an intramolecular C–C coupling reaction. A new chiral phosphine (<b>11</b>) is formed by the ligand-exchange reaction of <b>8</b> with PMe₃. Reactions of the single cycloiridated complex <b>3b</b> with terminal aromatic alkynes result in the corresponding five- and six-membered doubly cycloiridated complex <b>12</b> and/or η²-alkene coordinated complexes <b>13–15</b>; the latter discloses that the electronic effect of terminal alkynes affects the regioselectivity. While the single cyclorhodated complex <b>5b</b> reacts with terminal aromatic alkynes to form the corresponding six-membered cyclometalated complexes <b>16a–c</b> by vinylidene rearrangement/1,1-insertion. Plausible pathways for formation of insertion products <b>13–16</b> were proposed. Molecular structures of twelve new complexes were determined by X-ray diffraction

Total Water Splitting Catalyzed by Co@Ir Core–Shell Nanoparticles Encapsulated in Nitrogen-Doped Porous Carbon Derived from Metal–Organic Frameworks

Developing bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) toward overall water splitting with high efficiency and robust durability is highly desirable but very challenging. Herein, we report a highly efficient and robust bifunctional electrocatalyst for overall water splitting based on Co@Ir core–shell nanoparticles encapsulated in nitrogen-doped porous carbon derived from metal–organic frameworks. The series of Co@Ir/NC-<i>x</i> samples were prepared through a galvanic replacement of IrCl₃ with Co/NC, which was obtained by calcination of zeolitic imidazolate framework 67 (ZIF-67). In the electrocatalytic characterizations toward OER and HER, Co@Ir/NC-10% exhibited the best performance among the series, with an overpotential of 280 mV at a current density of 10 mA cm^–2 for OER, superior to the benchmark IrO₂ catalyst, and an overpotential of −121 mV at a current density of 10 mA cm^–2 for HER in 1 M KOH. Moreover, Co@Ir/NC-10% also demonstrated markedly higher long-term stability than IrO₂ for OER and superior long-term durability than Pt/C for HER. Finally, the overall water splitting catalyzed by the series of composites was explored and visually observed