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(1-methyl-1H-benzo[d]imidazol-2-yl) methanol (Hmbm) reacts with Mn(ClO4)2·6H2O to form heptanuclear disks [Mn7(mbm)12]·2(ClO4) (1) under ambient conditions. The heptanuclear cluster was previously described as a double calix unit with the hydroxides in the middle. The seven Mn(II) ions are essentially coplanar as expected for all edge-sharing octahedra, which can be intituled as a segment of Mg(OH)2 layer of brucite, so it is a symmetric disk. ESI–MS of crystals showed its stability in solution. Time-dependent mass spectrometry (MS) from solutions at different period of the assembly reveal a hierarchical sequence, [MnIII(mbm)2]+ → [MnII2(mbm)3]+ → [MnII4(mbm)6(ClO4)]+ → [MnIIIMnII6(mbm)12(ClO4)2]+. [ABSTRACT FROM AUTHOR]

The goal of material chemistry is to study the relationship among hierarchical structure, chemical reaction and precision preparation for materials, yet tracking pyrolysis process on multi-dimensional scale is still at primary stage. Here we propose packing mode analysis to understand evolution process in high temperature reaction. As a proof of concept, we first design a salan-ligated Mn3 (Mn3(3-MeOsalophen)2(Cl)2) cluster and pyrolyze it under an inert atmosphere directly to a mixed valence MnOx embedded in a porous N-doped carbon skeleton (MnOx/C). Meanwhile, combining thermogravimetry-mass spectrometry (TG-MS) with other characterization techniques, its pyrolysis process is precisely tracked real-time and Mn2+/Mn3+ ratios in the resulting materials are deduced, ensuring excellent electrochemical advantages. As a result, the as-preferred MnOx/C-900 sample reaches 943 F/g at 1 A/g, maintaining good durability under 5,000 cycles with 90% retention. The highlight of packing mode analysis strategy in this work would provide a favorable approach to explore the potential relationship between structure and performance in the future. [ABSTRACT FROM AUTHOR]

A tandem reaction of pyridin-2-ylmethanamine (L1′) with 8-hydroxyquinoline-2-carbaldehyde (HL1) assisted by FeCl3 was observed to give the new nitrogen heterocycle HL3 (HL3=2-(imidazo[1,5-a]pyridin-3-yl)quinolin-8-ol) as its Fe(III) complex, [Fe(L3)Cl2] (Fel). Electrospray ionization mass spectrometry (ESI-MS) reveals its formation involves three steps: (1) coordination of both HL1 and Ll′ to Fe, (2) aldehyde-amine coupling, and (3) ring closure. The results of electronic absorption spectroscopy, cyclic voltammetry, and density functional theory (DFT) calculations show the proximity of the optical transition energy to that of the excitation of 3O2 to 1O2, which prompted us to explore its application as a photosensitizer for photodynamic therapy (PDT). Photo-toxicity studies show that Fel exhibits the highest anti-proliferation efficiency in human breast cancer MDA-MB-231 cells under light irradiation. Moreover, studies with orthotopic models of breast cancer further expounded the anti-tumor activity of Fe1 with no significant toxicity to other organs and low retention in the body. [ABSTRACT FROM AUTHOR]

Delay, as an inevitable real-world phenomenon, is usually ignored in transport network design. A model of urban hybrid transport system with stochastic delay was created on the basis of the idealized public transport system design. After formulating the total trip time cost composed of accessing time in the sub-region of the city, waiting time at the public transport station, and in-vehicle time in the public transit network, the analytical properties of the total trip time cost function were investigated. The results show that in the urban hybrid transport network design, the total trip time cost reaches its approximate minimum in a δ-neighbourhood of buffer time of 1.5 min, and that through modelling optimal delay in hybrid transport system, the maximal synchronization can be achieved and operational efficiency and passenger satisfaction can be improved. The proposed modelling and analytical investigations are attempts to contribute to more realistic modelling of future idealized public transport system that involves more practical constraints. [ABSTRACT FROM AUTHOR]