We report the design of a unique bioinspired ligand merging redox-active catechol and flavin-related alloxazine substructures.Upon coordination with a Ni_((II))salt,this hybrid ligand forms a trinuclear complex contai...We report the design of a unique bioinspired ligand merging redox-active catechol and flavin-related alloxazine substructures.Upon coordination with a Ni_((II))salt,this hybrid ligand forms a trinuclear complex containing three NiII centers and three redox-active ligands.This air-stable metallic triangle stabilizing protons and electrons was studied by X-ray crystallography,infra-red(IR)and UV-vis spectroscopy,SQUID magnetometry(Superconducting QUantum Interference Device),MAS-NMR(Magic Angle Spinning-Nuclear Magnetic Resonance),EPR(Electron Paramagnetic Resonance),electrochemistry and DFT(Density Functional Theory).This multidisciplinary approach supports the presence of protons located on the organic ligands,and an electronic structure involving three high spin Ni_((II))ions strongly ferromagnetically coupled with radicals.Both ligand and complex provide a new design for molecular bricks and bioinspired energy storage devices.展开更多
文摘研究了Mg2+对克雷伯氏菌NIII2及其诱变株NIII2-1、NIII2-2发酵产絮凝剂特性的影响作用。实验表明,发酵液未外加或投加较少量Mg2+时,3菌株均不分泌黄色物质,且易产酸,致使絮凝剂产量低,小于1.5 g/L。发酵液中加入Mg2+的浓度在0.5~0.7 mmol/L范围,絮凝剂产生时,伴随黄色分泌物出现,发酵液p H稳定在7.5左右,同时絮凝剂产量大大提高,可达9.7 g/L。未投加Mg2+,3菌株所产絮凝剂Zeta电位负值较大,分别为-59.2、-56.6、-52.1 m V,且蛋白质与糖含量比值小于0.5,絮凝活性低;而投加Mg2+所产絮凝剂Zeta电位值可升至-48.0 m V,3菌株所产絮凝剂中蛋白和糖含量比值分别可提高到1.87、3.29、2.03,对高岭土所产生的SS去除率均大于93%。未投加Mg2+时,诱变株NIII2-1、NIII2-2所产絮凝剂含有相当多的O-链接和N-链接的结构,而其他情况下所产絮凝剂则主要是O-链接结构。
基金support by the initiative of Excellence IDEX-Unistra(ANR-10-IDEX-0002-02)from the French National Program“Investment for the Future”,Agence Nationale pour la Recherche(ANR-20-CE05-0005-01,ANR-18-CE092-0040-01)CNRS and Universitéde StrasbourgLabex NIE(ANR-11-LABX-0058_NIE within the Investissement d’Avenir program)for the support to the magnetometry platform.
文摘We report the design of a unique bioinspired ligand merging redox-active catechol and flavin-related alloxazine substructures.Upon coordination with a Ni_((II))salt,this hybrid ligand forms a trinuclear complex containing three NiII centers and three redox-active ligands.This air-stable metallic triangle stabilizing protons and electrons was studied by X-ray crystallography,infra-red(IR)and UV-vis spectroscopy,SQUID magnetometry(Superconducting QUantum Interference Device),MAS-NMR(Magic Angle Spinning-Nuclear Magnetic Resonance),EPR(Electron Paramagnetic Resonance),electrochemistry and DFT(Density Functional Theory).This multidisciplinary approach supports the presence of protons located on the organic ligands,and an electronic structure involving three high spin Ni_((II))ions strongly ferromagnetically coupled with radicals.Both ligand and complex provide a new design for molecular bricks and bioinspired energy storage devices.
