A discrete tetrahedral indium cage, {[In 12 (μ 3 -OH) 4 (HCO 2 ) 24 (tcma) 4 ]} (In 12 -GL), was synthesized solvothermally by the reaction of indium nitrate with the tripodal tricarboxylic acid ligand N,N,N-tris{(2′-carboxy[1,1′-biphenyl]-4yl)methyl}methylammonium chloride ([H 3 tcma] + Cl). This cage consists of four trimeric units [In 3 (μ 3 -OH)(μ 2 -CO 2 ) 3 (μ 2 -HCO 2 ) 3 ] and four [tcma] 2− ligands, which all perform as 3-connection nodes to bridge each other, resulting in a tetrahedral cage structure. The trimeric unit [In 3 (μ 3 -OH)(μ 2 -CO 2 ) 3 (μ 2 -HCO 2 ) 3 ] is observed for the first time in the family of In-based metal−organic structures and can be considered as an evolution of a 6-connected [In 3 (μ 3 -O)(μ 2 -CO 2 ) 6 ] unit. Each In 3+ is terminally coordinated by a μ 1 -HCO 2 group. This cage contains potential Lewis acidic/basic active sites endowed by In 3+ ions as Lewis acidic sites and the uncoordinated oxygen atoms of μ 1 -HCO 2 moieties as Lewis basic sites and was explored as an effective heterogeneous catalyst in the cycloaddition of CO 2 with epoxides and the Strecker reaction for amino nitriles. These catalytic reactions were deduced to happen on the surface of the In 12 -GL cage.

The controlling synthesis of novel nanoclusters of noble metals (Au, Ag) and the determination of their atomically precise structures provide opportunities for investigating their specific properties and applications. Here we report a novel silver nanocluster [Ag307Cl62(SPh t Bu)110] (Ag307) whose structure is determined by X-ray single crystal diffraction. The structure analysis shows that nanocluster Ag307 contains a Ag167 core, a surface shell of [Ag140Cl2S110], and a Cl60 intermediate layer located between Ag167 and [Ag140Cl2S110]. It is a first example that such many chlorides are intercalated into a Ag nanocluster. Chlorides are released in situ from solvent CHCl3. Nanocluster Ag307 exhibits superstability. Differential pulse voltammetry experiment reveals that Ag307 has continuous charging/discharging behavior with a capacitance value of 1.39 aF, while the Ag307 has a surface plasmonic feature. These characteristics show that Ag307 is of metallic behavior. However, its electron paramagnetic resonance (EPR) spectra display a spin magnetic behavior which could be originated from the unpassivated dangling bonds of surface atoms. The direct capture of EPR signals can be attributed to the Cl– intercalating layer which partly suppresses the electronic interactions between core and surface atoms, resulting in the relatively independent electronic states for core and surface atoms.

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BACKGROUND: T-2 toxin (T-2) is a potent mycotoxin and a common contaminant of aquatic animal feed, posing a serious risk to health and aquatic animals. We investigated the effect of T-2 on shrimp muscle proteins using proteomics and conventional biochemical methods. Shrimp were fed a diet containing T-2 at 0-12.2 mg kg −1 for 20 days, and changes to the muscle protein composition, ATPase activities, and the sulfhydryl (SH) content and hydrophobicity of actomyosin (AM) were determined. A proteomics study of the proteins was conducted with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional (2D) electrophoresis, and matrix-assisted laser desorption/ionization -time of flight mass spectrometry (MALDI-TOF/TOF MS). (1.2 mg kg −1 ), the levels of three major muscle proteins (myofibrillar, sarcoplasmic, and stroma) increased but at higher concentrations they declined progressively. T-2 exposure also led to a breakdown of muscle proteins as evidenced by increases in alkali-soluble protein and the surface hydrophobicity (SoANS) of AM. Thirty differentially expressed proteins were detected, 12 of which showed a concentration-response relationship with T-2 exposure. Among them, 11 homologous proteins were identified by mass spectrometry (MS), with several being key enzymes in energy metabolism. RESULTS: Exposure to T-2 markedly affected the muscle protein composition of shrimp in a concentration-responsive manner that displayed a diphasic effect. At a low T-2 concentrationCONCLUSION: This study demonstrated that T-2 exposure at medium to high concentrations could significantly affect the protein composition and quality of shrimp muscle, and potentially some of its key metabolisms. One of the arginine kinases (spot 27) was particularly responsive to T-2 and could potentially be used as a biomarker protein for T-2 intoxication by shrimp. /jsfa dine muscle stored at 0 ∘ C. J Food Sci 65:40-47 (2000).30 Tsuchiya T, Tsuchiya Y, Nonomura Y and Matsumoto JJ, Prevention of freeze denaturation of carp actomyosin by sodium glutamate.

A fish-basket-shaped [Co24] cluster, [Co24(μ3-O)4(ampc)4(μ3-OH)4(μ2-OH)4(NO3)5(HCO2)22(H2O)10]·[(HCO2)·2(CH3OH)·x(H2O)], was woven by bridging oxygen atoms from O(2-), OH(-), NO3(-) and HCO2(-) groups, and stabilized terminally by a semi-rigid organic ligand 4',4'-[(dimethylamino)dimethylene]-bis[(1,1'-biphenyl)-2-carboxylate] (ampc(-)). Magnetic analyses indicate that the [Co24] cluster exhibits two types of spin canting orders, spin flop and a small hysteresis with a coercive field of ca. 661 Oe and a remanent magnetization of 0.466 Nβ.