H2 Transformations on Graphene Supported Palladium Cluster: DFT-MD Simulations and NEB Calculations

Molecular dynamics simulations based on density functional theory were employed to investigate the fate of a hydrogen molecule shot with different kinetic energy toward a hydrogenated palladium cluster anchored on the vacant site of a defective graphene sheet. Hits resulting in H2 adsorption occur until the cluster is fully saturated. The influence of H content over Pd with respect to atomic hydrogen spillover onto graphene was investigated. Calculated energy barriers of ca. 1.6 eV for H-spillover suggest that the investigated Pd/graphene system is a good candidate for hydrogen storage.

Terminal Schwann cell and vacant site mediated synapse elimination at developing neuromuscular junctions

Synapses undergo transition from polyinnervation by multiple axons to single innervation a few weeks after birth. Synaptic activity of axons and interaxonal competition are thought to drive this developmental synapse elimination and tested as key parameters in quantitative models for further understanding. Recent studies of muscle synapses (endplates) show that there are also terminal Schwann cells (tSCs), glial cells associated with motor neurons and their functions, and vacant sites (or vacancies) devoid of tSCs and axons proposing tSCs as key effectors of synapse elimination. However, there is no quantitative model that considers roles of tSCs including vacancies. Here we develop a stochastic model of tSC and vacancy mediated synapse elimination. It employs their areas on individual endplates quantified by electron microscopy-based analyses assuming that vacancies form randomly and are taken over by adjacent axons or tSCs. The model reliably reproduced synapse elimination whereas equal or random probability models, similar to classical interaxonal competition models, did not. Furthermore, the model showed that synapse elimination is accelerated by enhanced synaptic activity of one axon and also by increased areas of vacancies and tSCs suggesting that the areas are important structural correlates of the rate of synapse elimination.

The impacts of historic districts on residential property land values in Australia

Purpose Focusing on the externality effects of historic districts, this paper aims to assess and compare the impact of historic district designation on the value of residential vacant land property. Design/methodology/approach Hedonic regression is used to analyze data from 4,233 residential vacant site transactions to measure the influence of historic district designation on the price of residential vacant site properties. Findings Results support established theory and research on other residential property types, showing a significant and positive relationship between designation in a historic district and property prices. Residential vacant sites located in a designated historic district sold at a 10-11 per cent premium compared to similar vacant sites not located in a historic district. Originality/value This is the first empirical study of the influence of historic districts on residential vacant land property. The paper extends limited previous literature on the externality effects of historic districts through detailed analysis of a large Australian housing market (Brisbane).

Vacancy effects on the electronic structure of MgO compound

We have investigated the possibility to find [Formula: see text] ferromagnetism (FM) in the non-stoichiometric [Formula: see text] compound using the full potential linearized augmented plane wave [Formula: see text] method. We have examined the oxygen vacancy effect on the electronic structure of [Formula: see text] compound realizing the 128 atoms supercell. Our calculations predict that the cation vacancies cause the FM in [Formula: see text], where the magnetism is often created by the oxygen atoms nearest neighbors of the Mg vacant site, with a spin magnetic moment of 0.21 [Formula: see text]B/atom. We have reported a strong evidence of the existence of FM at room temperature, as we extended our studies to demonstrate the ability to induce intrinsic magnetic moments in MgO with cationic vacancies (Mg).

VACANCY GENERATION AND ADSORPTION OF Cu ATOM AT Ag(1 1 1) SURFACE DURING DIFFUSION OF Cu-TRIMER

In this paper, the vacancy generation at (1 1 1) surface of silver ( Ag ) and the adsorption of copper ( Cu ) atom in the vacant site at Ag (1 1 1) surface has been studied using molecular dynamics (MD) simulation technique. The run of micro-canonical constant energy (NVE) ensemble results the generation of vacancy at 700 K in the presence of Cu -trimer, and its migration is observed toward the island as a result of self-diffusion of the surface layer atom. The energy of vacancy generation at Ag surface is found to be Ev = 1.078 eV , in the presence of Cu -trimer. The popped-up Ag adatom combines with Cu -trimer, making a mixed-tetramer ( Cu 3– Ag island). The adsorption energy of the Cu -atom among the mixed-tetramer island into the substitutional site is Es = ~ -0.813 eV , leaving a mixed-trimer ( Cu 2– Ag island) at Ag (1 1 1). Moreover, the presence of the island creates some anharmonic effects like dislocations and fissures at the surface. These dislocations and fissures show a trend of attraction to each other and also migrate toward the island, during the time evolution of the system.