A series of dioxomolybdenum(VI) complexes with similar hydrazone ligands have been prepared, specifically [MoO2L1(MeOH)] (1), [MoO2L2(MeOH)] (2) and [MoO2L3(MeOH)] (3), where L1, L2 and L3 are the dianionic forms of 2-chloro-N′-(2-hydroxybenzylidene)benzohydrazide, 2-chloro-N′-(2-hydroxy-5-methylbenzylidene)benzohydrazide and N′-(3-bromo-5-chloro-2-hydroxybenzylidene)-2-chlorobenzohydrazide, respectively. The complexes were characterized by physicochemical and spectroscopic methods and also by single-crystal X-ray determination. The hydrazone ligands coordinate to the Mo atoms through their phenolate O, imine N and enolic O atoms. The Mo atoms are six-coordinated in octahedral geometries. The complexes show high catalytic activities and selectivities in the epoxidation of cyclohexene with tert-butylhydroperoxide as primary oxidant. 相似文献
Mass spectrometry (MS)-based proteome profiling is essential for molecular diagnostics in modern biomedical study. To date, sample preparation including protein extraction and proteolysis is still very challenging and lack of efficiency. Recently tips-based sample preparation protocols exhibit strong potentials to achieve the goal of “a proteome in an hour”. However, in-tip proteolysis is still rarely reported and far from ideal for dealing with complex bio-samples. In this work, nanoreactors encapsulated micropipette tips were demonstrated as high performance devices for fast (∼minutes) and multiplexing proteolysis to assist the profiling of cancer cells proteome. Nanoporous silica materials with controlled pore size and surface chemistry were prepared as nanoreactors and encapsulated in micropipette tips for efficient in situ proteolysis. The as-constructed device showed desirable sensitivity (LOD of 0.204 ± 0.008 ng/μL and LOQ of 0.937 ± 0.055 ng/μL), selectivity, stability (two months under −20 °C), reusability (at least 10 times), and little memory effect in MS based bottom-up proteomic analysis. It was used for comprehensive protein mapping from cancer cell lines. The number of identified proteins was increased by 18%, 22%, 52%, and 52% dealing with HepG2, F56, MCF7, and HCCLM3 cancer cells, compared to traditional in-solution proteolysis based bottom-up proteomic strategy. With the enhanced performance, our work built a novel, efficient and miniaturized platform for facile proteomic sample preparation, which is promising for advanced biomarkers discovery in biomedical study. 相似文献
Tin (Sn) has been considered as an attractive anode material for sodium-ion batteries (SIBs) due to its high theoretical capacity (847 mAh g?1). Nevertheless, its low conductivity and large volume change during cycling essentially prevent the possibility of high capacity and long-term cycle for SIBs. In this work, Sn nanoparticles are well embedded into the highly ordered mesoporous carbon (CMK-3) matrix (Sn@CMK-3) using a facile sonochemical method combined with heat treatment. The resultant Sn@CMK-3 nanohybrid electrode delivers an initial charge capacity of 412 mAh g?1 at 100 mA g?1. A reversible capacity of 337 mAh g?1 is obtained after 200 cycles, indicating the good cycle stability of the nanohybrid structure. The electrode also shows a potential rate capability, which maintains a capacity of 228 mAh g?1 at 1000 mA g?1. When the current density returns to 50 mA g?1, the capacity goes back to 381 mAh g?1, with a capacity retention of 86.9%. The enhanced sodium storage performance of Sn@CMK-3 nanohybrid can be related to the synergistic effect between CMK-3 and Sn.
Graphical abstract Sn@CMK-3 nanohybrid with Sn nanoparticles uniformly distributed into the highly ordered mesoporous carbon matrix exhibited good cycling performance and rate capability.
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