One-step synthesis of biofunctional carbon quantum dots for bacterial labeling.

In this study, we used a simple one-step dry heating method to synthesize mannose-modified fluorescent carbon quantum dots (Man-CQDs) from solid ammonium citrate and mannose, and successfully applied for labeling Escherichia coli. The highly soluble Man-CQDs had an average particle diameter of 3.1±1.

Detection of arsenic(III) through pulsed laser-induced desorption/ionization of gold nanoparticles on cellulose membranes.

We have developed an assay based on gold nanoparticle-modified mixed cellulose ester membrane (Au NPs-MCEM) coupled with laser-induced desorption/ionization mass spectrometry (LDI-MS)-for the detection of arsenic(III) ions (arsenite, AsO2(-)) in aqueous solution. When the Au NPs reacted with lead ions (Pb(2+)) in alkaline solution (5 mM glycine-NaOH, pH 12), Au-Pb complexes, PbO, and Pb(OH) were formed immediately on the Au NP surfaces. The Pb species reacted rapidly with subsequently added AsO2(-) to form PbOAs2O3, (PbO)2As2O3, and/or (PbO)3As2O3 shells (2-5 nm) on the Au NPs' surfaces.

Behavior of water molecules near monolayer-protected clusters with different terminal segments of ligand.

Molecular dynamics simulations are performed to investigate the behavior of water molecules near gold monolayer protected clusters (MPCs) with two different types of surfactant, HS(CH(2))(5)(OCH(2)CH(2))(2)COOH (type1) and HS(CH(2))(11)COOH (type2). The effects of the different moieties of the two ligands on the local structure of the water molecules are quantified by means of the reduced density profiles of oxygen and hydrogen atoms, and the hydrogen bond statistics. The adsorption characteristics of water molecules are evaluated by means of their residence time near the MPCs.

Influence of alkanethiol self-assembled monolayers with various tail groups on structural and dynamic properties of water films.

Molecular dynamics simulations are performed to investigate the structural and dynamic properties of a water layer lying on a clean Au(111) surface and on alkanethiol self-assembled monolayers (SAMs) with three different tail groups: methyl, carboxyl, and hydroxyl. The effects of these functional groups on the local structure of the water are quantified by analyzing the reduced density profiles of the oxygen and hydrogen atoms, the average number of hydrogen bonds, and the distribution of the O-H bond angle, respectively. Meanwhile, the dynamic properties of the water layer are evaluated by analyzing the diffusion coefficients of the water molecules in the xy-plane and z-direction.

Temperature sensing using individual single-walled carbon nanotubes.

Molecular dynamics simulations and quantum transport theory are employed to study the temperature-dependent electrical properties of individual (12,0) zigzag and (5,5) armchair carbon nanotubes deposited on silicon substrates. The results demonstrate that the magnitude of the leakage current depends on the length of the nanotube. Furthermore, the leakage current is generated periodically along the length of the nanotube.

Molecular dynamics simulations of structural features and diffusion properties of fullerene-in-water suspensions.

This study performs molecular dynamics (MD) simulations to investigate the structural features and diffusion properties of fullerene-in-water suspensions. The numerical results reveal that an organized structure of liquid water is formed close to the surface of the fullerene molecule, thereby changing the solid/liquid interfacial structure. The organized structure formation becomes more pronounced as the fullerene size is reduced.

Molecular dynamics investigation into the structural features and transport properties of C60 in liquid argon.

Molecular dynamics (MD) simulations were performed to investigate the structural features and transport properties of C60 in liquid argon. The results reveal that an organized structure shell of liquid argon is formed close to the surface of a C60 fullerene molecule, thereby changing the solid/liquid interfacial structure. Furthermore, the simulation indicates that the C60-liquid argon fluid becomes structurally more stable as the C60 molecule volume fraction and the temperature increase.

The effect of added oversized elements on the microstructure of binary alloy nanoparticles.

Molecular dynamics simulations are used to investigate the microstructures of Cu-Ni nanoparticles with different concentrations of oversized atoms added to them. A many body second moment tight binding approximation potential is adopted to model the interatomic interactions. The Honeycutt-Anderson (HA) pair analysis technique is adopted to analyse in detail the transformation between local structures at different temperatures.

An investigation into the melting of silicon nanoclusters using molecular dynamics simulations.

Using the Stillinger-Weber (SW) potential model, we have performed molecular dynamics (MD) simulations to investigate the melting of silicon nanoclusters comprising a maximum of 9041 atoms. This study investigates the size, surface energy and root mean square displacement (RMSD) characteristics of the silicon nanoclusters as they undergo a heating process. The numerical results reveal that an intermediate nanocrystal regime exists for clusters with more than 357 atoms.