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A new molecular insight into transport and activation of ochratoxin A (OTA) is discussed. The lifetime of OTA in living systems is dependent on the presence of serum albumin.

Ochratoxins are fungal metabolites known to contaminate human and animal feed. By using optical spectroscopy, the binding of three Ochratoxin A (OTA) derivatives ochratoxin B (OTB), ochratoxin hydroquinone (OHQ), and O-methylated OTA(MOA) to HSA is examined.

Research describes the syntheses of an array of N-substituted-tach-Cu(II)-dihalide complexes and the cognate tach ligands together with their solid-state and solution structure. Results discuss the Cu(II) complexes of N,N',N'-trialkyltach derivatives of cis,cis-1,3,5-triaminocyclohexane.

Electron paramagnetic resonance spectroscopic analysis indicates that the dicopper complex is formed only if bis(p-nitrophenyl) phosphate (BNPP) is present. The hydrolysis of activated phosphate diesters, such as BNPP, by dicopper complexes and the mechanism of action are discussed.

Co and carbon nanotube (CNT) were prepared as anode materials to be used in lithium rechargeable batteries from the zeolitic‐imidazolate framework‐67 (ZIF‐67) using the solvothermal method. By annealing ZIF‐67 at different temperatures between 400 and 700 °C, the carbon framework was changed to CNTs, and Co or Co3O4 nanoparticles were embedded in the CNTs (Co or Co3O4/CNT). The Co/CNT was converted to Co‐Co3O4/CNT by further treatment at 160 °C in air. The Co3O4/CNT showed high initial capacities (1582 mAh/g) but poor capacity retention during cycling. However, the air treatment of the Co/CNT at 160 °C enhanced its discharge capacity (935 mAh/g) and capacity retention during cycling. [ABSTRACT FROM AUTHOR]

As organic ionic crystals, C2‐, C3‐, and C4‐alkylene α,ω‐bis[N,N′‐(4‐alkylpyridinium)] PF6− salts are synthesized to investigate their thermal properties and phase behaviors along with chemical structure changes. The X‐ray crystal structure of 1,2‐bis[N,N′‐(4‐methylpyridinium)]ethane 2PF6− (2–1) showed that two pyridinium rings in one cation molecule and two pyridinium ring planes of neighboring molecules were exactly parallel. Multiple C−H⋅⋅⋅F hydrogen bonds were observed for all protons of the bis‐pyridinium with PF6− anions. Interestingly, most of the prepared C2‐bridged dicationic bis‐pyridinium PF6− salts showed solid–solid phase transitions, which are typical features of soft crystalline materials, such as plastic and liquid crystals. Colorfully aligned crystalline textures of the polarized optical microscope images are formed with strong birefringence for the soft crystalline phase of 1,2‐bis[N,N′‐(4‐n‐propylpyridinium)]ethane PF6−, showing a low entropy of fusion (ΔSf=25.0 J mol−1 K−1). The C2‐bridged n‐undecyl (2–11) and n‐dodecyl (2–12) salts exhibit a very soft solid phase, showing large heat absorptions and entropy changes during their multiple solid‐solid phase transitions. Additionally, the C3‐ and C4‐bridged dicationic (bis)pyridinium PF6− salts are prepared to determine the property changes with different bridge lengths. The longer alkylene connected salts are thermally more stable than the C2‐bridged compounds and show only one melting phase transition. [ABSTRACT FROM AUTHOR]

Highly porous LaCoO3 perovskite was synthesized by a nanocasting method using a mesoporous silica template and subsequently applied as a bifunctional catalyst for the oxygen reduction and evolution reactions in alkaline solution. The La-Co citrate complex was mixed a porous SBA-15 silica template, and then, calcinated at 650 °C to prepare a LaCoO3/SBA-15 composite. Highly porous LaCoO3 was prepared by treating this composite with NaOH to remove the SBA-15 silica template. The obtained LaCoO3 showed a very rough surface, high surface area, and relatively small particle size compared with LaCoO3 prepared by the sol-gel method. The catalytic performance of the highly porous LaCoO3 for the oxygen reduction and evolution reactions was electrochemically measured in alkaline solution. LaCoO3 prepared by the nanocasting exhibited higher cell performance than that prepared by sol-gel method due to its larger surface area. [ABSTRACT FROM AUTHOR]

Carbon‐wrapped Co/Ni metal nanoparticles (C@CoxNi1−x) were synthesized by calcination of bimetallic metal–organic frameworks (Co/Ni‐MOFs), prepared by a hydrothermal reaction, under N2 atmosphere and explored as bifunctional catalysts for oxygen reduction reactions (ORR) and oxygen evolution reactions (OER) for rechargeable Zn‐air batteries. Linear sweep voltammetry (LSV) measurements indicated that the composite obtained at 600°C (N600) exhibited superior electrochemical performance to other composites obtained at 500, 700, 800, and 900°C, respectively. Also N600 exhibited stable current–voltage profiles in a cycling test conducted in 8 M KOH solution for 200 h, suggesting that N600 can be a potential catalyst for rechargeable Zn‐air batteries. Synthesis of carbon‐wrapped Co/Ni catalysts, C@CoxNi1−x, catalysts as a bifunctional catalyst for air electrodes in rechargeable Zn‐air batteries. [ABSTRACT FROM AUTHOR]