Ion irradiation of nanoparticles leads to enhanced sputter yields if the nanoparticle size is of the order of the ion penetration depth. While this feature is reasonably well understood for collision-cascade sputtering, we explore it in the regime of collision-spike sputtering using molecular-dynamics simulation. For the particular case of 200-keV Xe bombardment of Au particles, we show that co...

Stark deceleration allows for precise control over the velocity of a pulsed molecular beam and, by the nature of its limited phase-space acceptance, reduces the energy width of the decelerated packet. We describe an alternate method of operating a Stark decelerator that further reduces the energy spread over the standard method of operation. In this alternate mode of operation, we aggressively ...

In recent research on modelling road collisions very little attention has been paid  to rear-end chain reaction collisions, which is characterized by more than two vehicles involved in a collision at the same time. The core aim of the present research is to develop a methodology to estimate such potential collision probabilities based on a proactive perspective, where deceleration rate to avoid...

The collision of two cylindrical hydrogen-free diamond-like carbon (DLC) asperities with approximately 60 % sp3 hybridization has been studied using classical molecular dynamics. The severity of the collision can be controlled by the impact parameter b that measures the width of the projected overlap of the two cylinders. For a cylinder radius of R = 23 nm, three collisions with b = 0.5 nm, b =...

frothers havea profoundeffectonbubble size and also flotation efficiency. in present study the effect of type and dosage of frothers on the flotation response of coarse particles of quartz was investigated.  therefore, flotation response of coarse particles using frothers such as mibc, pine oil, poly propylene glycol with concentration of 0, 25, 50 and 75 g/t, was obtained respectively. for all...

The reactions of atomic carbon, C(P j), with benzene, C6H6(X A1g), and with d6-benzene, C6D6(X A1g) were investigated at twelve collision energies between 8.8 and 52.5 kJ mol 21 using the crossed molecular beams technique. Forward-convolution fitting of the data, high-level electronic structure calculations, and Rice–Ramsperger–Kassel–Marcus ~RRKM! investigations on the singlet and triplet C7H6...

Electron re-scattering in a strong laser field provides an important probe of molecular structure and processes, and can allow for time resolved study of nuclear and electronic dynamics at sub-femtosecond timescales with Angstrom spatial resolution. In such experiments a molecule is ionised in a strong, few cycle, laser field. The changes in sign of the laser field during the cycle can cause th...

The decay of the plasma grating formed at the intersection of two femtosecond filaments is measured in several molecular and atomic gases. The grating evolution is ruled by ambipolar diffusion in atomic gases and by a combination of ambipolar diffusion and collision-assisted free electron recombination in molecular gases. Electron diffusion and recombination coefficients are extracted for Ne, A...

The reaction of the dicarbon molecule (C2) with D1-acetylene (HCCD) was carried out under single-collision conditions in a crossed molecular beams machine to investigate deuterium enrichment processes in cold molecular clouds and in circumstellar envelopes of carbon stars. The experiments were merged with electronic structure calculations. Our combined experimental and theoretical studies sugge...