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The mechanism that forms the different resonant families of the asteroid belt between the orbits of Jupiter and Mars is not completely understood. To study the resonant capture mechanism and the origin of orbits of some asteroid families in mean motion resonances with Jupiter, furthermore to give a possible explanation of this problem, we performed in situ numerical simulations of the 3-dimensional semi-analytical model of the Sun-Jupiter-particle system. We examined the numbers and orbits of particles captured along the Jupiter's present orbit (including the L3, L4 and L5 Lagrange points) for 7000 Jupiter years. In our simulations we did not distinguish between planetesimals, interplanetary dust and asteroids, because we investigated the restricted three-body problem taking into account only gravitation. We found that the asteroid families in 4:3, 1:1, 4:5, 3:4, 2:3, 5:8, 4:7 and 5:9 resonances may have formed from the asteroids captured, launched and kept on their orbits not only by the L4 and L5 points, but also by the unstable L3 point and certain areas along the Jupiter's path. Furthermore, we found possible new asteroid families in 4:5 and 3:4 resonances, no any member of which have yet been identified. Thus, Jupiter forms a shield which protects the inner Solar System from asteroids moving with speeds not significantly differing from that of Jupiter. • Our aim is to demonstrate the resonant capture mechanism of dynamically cold particles along the Jupiter's orbit. • We performed in situ simulations of the 3D semi-analytical model of the Sun-Jupiter-particle system. • The capture efficiency of both the L4 and L5 points at the Jupiter's aphelion is 24% higher than at its perihelion. • The particles captured along the Jupiter's present orbit form the 1:1, 4:3, 4:5, 3:4, 2:3, 5:8, 4:7, 5:9 resonance families. [ABSTRACT FROM AUTHOR]

The current investigation was conducted to understand the effect of 1wt. % silicon carbide (SiC) in the Sn–3.5Ag–0.5Cu (SAC305) lead-free solder alloy which was produced by the powder metallurgy method. A systematic investigation of the microstructure of the solidified composite solder along with its wetting behavior was carried out at different reflow temperatures (230°C–290°C). From microstructure investigation, it was clear that SiC ceramic particles influence the development of IMCs at the Cu–Sn interface and refine microstructure in the bulk solder region. Micro-cracks were detected at Cu/SAC interface and also in the Cu 6 Sn 5 layer. This is due to the development of extremely (brittle) intermetallic layer and ductile nature of Sn–3.0Ag–0.5Cu solder. The intermetallic layer thickness increased substantially with the increase of reflow temperatures (230°C–290°C). A uniform distribution of SiC, Ag 3 Sn, and Cu6Sn5 IMCs were found in the bulk b-Sn matrix. The result shows that the SiC particles promote the extra nucleation sites for the development of b-Sn phase and IMCs in the solidified structure. In addition to this, SiC particles, b-Sn dendrites and IMCs can prevent dislocation slippage which helps in attaining a strong solder joint due to strong strengthening effect. The results showed that the spread ratio, spread factor, and the relative spread area (RSA) increased while the equilibrium contact angle decreased with an increase in reflow temperature. This can be attributed to the strong adsorption effect and high surface free energy of the SiC particles. Image 1 • SAC305- 1%SiC composite solder is prepared by the powder metallurgy method. • Pores and cracks are detected in the Cu 6 Sn 5 IMC. • Spreading area (RSA), spreading ratio, and spread factor is analyzed corresponding to the reflow temperatures. • Contact angles are measured by direct and indirect methods. [ABSTRACT FROM AUTHOR]