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The thermally vibrational properties of icosahedral (ICH) and face-center-cubic (FCC) copper nanoclusters have been compared by carrying out molecular dynamics simulations with a local-environment-dependent tight-binding potential. Although both ICH and FCC copper nanoclusters exhibit a low-and high-energy enhancement of vibrational density of states (VDOS) in comparison with the bulk copper, the vibrational properties of nanoclusters show a strong structure-dependent feature. The different structure is revealed to result in the different atom package, the different lattice shrinkage, the different local pressure, and thus the different VDOS. The different atom package at the surfaces of clusters is responsible for the different lowenergy VDOS in a different power-law behavior between the FCC and ICH clusters. The lattice contraction and the internal pressure in the sense of the bulk are unified to explain the enhanced high-energy tail in the VDOS of FCC clusters, but not in the case of ICH clusters.

Carbon materials have been widely utilized as supports in different catalytic reactions; however, it has been rarely reported that carbon supports were used in the catalytic oxidation of volatile organic compounds because they have no catalytic activity and poor catalytic stability compared to metal supports. Herein, fabricating optimal carbon supports to facilitate the catalytic oxidation of benzene has become a great concern of research. A novel activated carbon (biomass−HCO) was prepared from different waste biomass via a three-stage route without the participation of harmful chemical reagents. The successful synthesis of C−O bonds and CO bonds through this method could greatly increase oxygen-enriched functional groups and defects of the biomass−HCO surface, which could effectively promote the nucleation and growth of platinum. Benzene oxidation reactions were performed to evaluate the activity of catalysts. The results demonstrated that Pt/biomass−HCO catalyst made the reaction temperature sharply decrease to 160 °C at T 90 . The 150 h on-stream reaction exhibited great thermal stability of Pt/biomass−HCO. The DFT calculations verified the strong interaction between Pt nanoparticles and carbon supports. Moreover, our demonstration of the superior benzene oxidation activity of Pt/ biomass−HCO catalysts revealed that it is feasible to utilize oxygen-enriched biomass carbon as catalytic supports toward the oxidation of volatile organic compounds.

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In this paper, the internal mechanism of solid deuterium spatial distribution induced by infrared radiation is studied. The changes in spatial distribution and micro-structure of solid deuterium are also discussed as the results of wavelength and heating time of IR light. It is found that the micro-structure of solid deuterium which is irradiated by a special IR light is changed from polycrystal to monocrystal, the solid deuterium is redistributed and becomes more uniform and transparent. The best wavelength of IR light for heating solid deuterium is 3140 nm. When the output power of 3140 nm IR light is 100 upW, the redistribution time of solid deuterium is about 18 min.