Glutathione (GSH) plays a crucial role in various physiological processes and its imbalances are closely related to various pathological conditions. Probes for detection and imaging of GSH are not only useful for understanding GSH chemical biology but are also important for exploring potential theranostic agents. Herein, we report a fast intramolecular thiol-activated arylselenoamides ()-based fluorescent probe using 2,4-dinitrophenyl alkylthioether as a sulfydryl-selective receptor for the first time.
View Article and Find Full Text PDFGold (Au) nanocatalysts present outstanding activity for many reactions and have long attracted much attention, but the size effect of sub-nano-clusters on catalytic activity lacks systematic research. Using CO oxidation as a probe reaction, the size-dependent catalytic capability of sub-nano-Au clusters was explored. The global-minimum (GM) structures of Au ( = 2-300, <2.
View Article and Find Full Text PDFThe highly selective hydrogenation to remove olefins is a significant refining approach for the reformate. Herein, a library of transition metal for reformate hydrogenation is tested experimentally to validate the predictive level of catalytic activity from our theoretical framework, which combines ab initio calculations and microkinetic modeling, with consideration of surface H-coverage effect on hydrogenation kinetics. The favorable H coverage of specific alloy surface under relevant hydrogenation condition, is found to be determined by its corresponding alloy composition.
View Article and Find Full Text PDFRecently, a lot of attention has been dedicated to double- or triple-atom catalysts (DACs/TACs) as promising alternatives to platinum-based catalysts for the oxygen reduction reaction (ORR) in fuel cell applications. However, the ORR activity of DACs/TACs is usually theoretically understood or predicted using the single-site association pathway (O → OOH* → O* → OH* → HO) proposed from Pt-based alloy and single-atom catalysts (SACs). Here, we investigate the ORR process on a series of graphene-supported Fe-Co DACs/TACs by means of first-principles calculation and an electrode microkinetic model.
View Article and Find Full Text PDFAn unprecedented HS release from cysteine esters and amides (CysO/NHR) under physiological conditions was discovered and the plausible mechanism was proposed. Alkylation of the amino moiety of cysteine esters enables the HS release to be tuned and further provides support to the mechanistic insights. This discovery not only provides new insights into several fundamental science issues including non-enzymatic HS-produced pathways, but also inspires new tunable cleavable motifs for sustained release of arylthiols and even for prodrug design.
View Article and Find Full Text PDFAlloying is an effective approach to improve the catalysis performance of Pd-based catalysts for the selective hydrogenation of diolefins towards monoolefines. Herein, PdAgCu ternary nanoalloy catalysts were synthesised by a stepwise impregnation method for isoprene selective hydrogenation. The addition of a moderate amount of Ag and Cu to Pd significantly enhances the isoamylene selectivity in the isoprene hydrogenation, and decreases the non-desired over-hydrogenation.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
December 2013
Various nanostructures of 5,10,15,20-tetrakis(4-carboxyl phenyl)-porphyrin (H2TCPP) can be easily synthesized by a surfactant-assisted self-assembly (SAS) method at different temperatures. When the DMF solution of porphyrin monomer was injected into cetyltimethylammonium bromide (CTAB) aqueous solution by a syringe, diverse H2TCPP nanostructures dependent on the different temperatures, including hollow nanospheres, solid nanospheres and nanospheres with holes, were successfully obtained. As a result, the suitable concentration of the CTAB aqueous solution used to form nanostructues of porphyrin ranges from 0.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
May 2009
Abstract The supported nickel phosphate precursors were prepared by incipient wetness impregnation using nickel nitrate as nickel source, diammonium hydrogen phosphate as phosphorus source, and MCM-41, MCM-48, SBA-15 and SBA-16 as supports, respectively. Then, the supported Ni2 P catalysts were prepared by temperature-programmed reduction in flowing Hz from their nickel phosphate precursors. The in situ diffuse reflectance FTIR spectroscopy (DRIFTS) analysis with the probe molecule CO was carried out to characterize the surface properties.
View Article and Find Full Text PDFActa Crystallogr Sect E Struct Rep Online
June 2009
In the title compound, C(6)H(16)NO(3) (+)·C(7)H(4)NS(2) (-), the cations and anions are connected by O-H⋯N and O-H⋯S hydrogen bonding. Weak C-H⋯O hydrogen bonding between adjacent cations helps to stabilize the crystal structure.
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