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The Kirkendall effect has been recently used to produce hollow nanostructures by taking advantage of the different diffusion rates of species involved in the chemical transformations of nanoscale objects. Here we demonstrate a nanoscale Kirkendall cavitation process that can transform solid palladium nanocrystals into hollow palladium nanocrystals through insertion and extraction of phosphorus. The key to success in producing monometallic hollow nanocrystals is the effective extraction of phosphorus through an oxidation reaction, which promotes the outward diffusion of phosphorus from the compound nanocrystals of palladium phosphide and consequently the inward diffusion of vacancies and their coalescence into larger voids. We further demonstrate that this Kirkendall cavitation process can be repeated a number of times to gradually inflate the hollow metal nanocrystals, producing nanoshells of increased diameters and decreased thicknesses. The resulting thin palladium nanoshells exhibit enhanced catalytic activity and high durability toward formic acid oxidation.

The formaldehyde emission performance of wood-based panels treated with temperature-sensitive microcapsules was evaluated in this study. Formaldehyde scavenger-filled microcapsules were synthesized by the emulsion-solvent method using ethylcellulose and poly(N-isopropylacrylamide) (PNIPAM) as shell materials containing urea. The results demonstrated that the temperature-sensitive microcapsules exhibited perfect core–shell structures at a core/shell/PNIPAM ratio of 2:2:1. The loading capacity and loading efficiency of the functional core material of the microcapsules reached 33% and 59%, respectively. Compared with untreated panels, panels based on the temperature-sensitive microcapsule scavenger had better performance in controlling free formaldehyde emissions, the formaldehyde emission of treated panels decreased by 42% and 41% at room temperature and 40°C, respectively. The results indicated that the reason why the wood-based panels had a long-term low-level emission was that the microcapsules showed different release behaviour at different temperature, so they have different release paths and release principles. [ABSTRACT FROM AUTHOR]

Calcium-dependent, neuronal adenylyl cyclase subtype 1 (AC1) is critical for cortical potentiation and chronic pain. NB001 is a first-in-class drug acting as a selective inhibitor against AC1. The present study delineated the pharmacokinetic (PK) properties of human-used NB001 (hNB001) formulated as immediate-release tablet. This first-in-human (FIH) study was designed as randomized, double-blind, placebo-controlled trial. hNB001 showed placebo-like safety and good tolerability in healthy volunteers. A linear dose-exposure relationship was demonstrated at doses between 20 mg and 400 mg. The relatively small systemic exposure of hNB001 in human showed low bioavailability of this compound through oral administration, which can be improved through future dosage research. Food intake had minimal impact on the absorption of hNB001 tablet. Animal experiments further confirmed that hNB001 had strong analgesic effect in animal models of neuropathic pain. In brain slice prepared from the anterior cingulate cortex (ACC), bath application of hNB001 blocked the induction of long-term potentiation (LTP). These results from both rodents and human strongly suggest that hNB001 can be safely used for the future treatment of different types of chronic pain in human patients. [ABSTRACT FROM AUTHOR]