EXPERIMENTAL AND THEORETICAL STUDY OF BINARY DROPLET HEAD-ON COLLISIONS IN MEMS

The experimental and theoretical investigations into the head-on collision between a landing droplet with another one resting on the PDMS substrate were addressed in this talk. The colliding process of the two droplets was recorded with highspeed camera. Four different responses after collision were observed in our experiments: complete rebound, coalescence, partial rebound with conglutination, and coalescence accompanied by conglutination. The contact time between the two colliding droplets was found to be in the range of 10-20 milliseconds. For the complete bouncing case, Hertz contact model was applied to estimate the contact time of the binary head-on colliding droplets with both the droplets considered as elastic bodies. The estimated contact time was in good agreement with the experimental result.

Correlation of NCAP performance with fatality risk in actual head-on collisions.

Mode of access: Internet.

The Head-On Colliding Process Of Binary Liquid Droplets At Low Velocity: High-Speed Photography Experiments And Modeling

The experimental and theoretical studies are reported in this paper for the head-on collisions of a liquid droplet with another of the same fluid resting on a solid substrate. The droplet on the hydrophobic polydimethylsiloxane (PDMS) substrate remains in a shape of an approximately spherical segment and is isometric to an incoming droplet. The colliding process of the binary droplets was recorded with high-speed photography. Head-on collisions saw four different types of response in our experiments: complete rebound, coalescence, partial rebound With conglutination, and coalescence accompanied by conglutination. For a complete rebound, both droplets exhibited remarkable elasticity and the contact time of the two colliding droplets was found to be in the range of 10-20 ms. With both droplets approximately considered as elastic bodies, Hertz contact theory was introduced to estimate the contact time for the complete rebound case. The estimated result Was found to be on the same order of magnitude as the experimental data, which indicates that the present model is reasonable. (C) 2008 Elsevier Inc. All rights reserved.

Passenger vehicle median crossover and head-on collision with another passenger vehicle, Linden, New Jersey, May 1, 2003 /

"PB2006-916202."

Dependence on pseudorapidity and on centrality of charged hadron production in PbPb collisions at root s(NN)=2.76 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Head-on infall of two compact objects: Third post-Newtonian energy flux

Head-on infall of two compact objects with arbitrary mass ratio is investigated using the multipolar post-Minkowskian approximation method. At the third post-Newtonian order the energy flux, in addition to the instantaneous contributions, also includes hereditary contributions consisting of the gravitational-wave tails, tails-of-tails, and the tail-squared terms. The results are given both for infall from infinity and also for infall from a finite distance. These analytical expressions should be useful for the comparison with the high accuracy numerical relativity results within the limit in which post-Newtonian approximations are valid.

Systematic study of the pi(-)/pi(+) ratio in heavy-ion collisions with the same neutron/proton ratio but different masses

A systematic study of the pi(-)/pi(+) ratio in heavy-ion collisions with the same neutron/proton ratio but different masses can help single out effects of the nuclear mean field on pion production. Based on simulations using the IBUU04 transport model, it is found that the pi(-)/pi(+) ratio in head-on collisions of Ca-48 + Ca-48, Sn-124 + Sn-124, and Au-197 + Au-197 at beam energies from 0.25 to 0.6 GeV/nucleon increases with increasing the system size or decreasing the beam energies. A comprehensive analysis of the dynamical isospin fractionation and the pi(-)/pi(+) ratio as well as their time evolution and spatial distributions demonstrates clearly that the pi(-)/pi(+) ratio is an effective probe of the high-density behavior of the nuclear symmetry energy.

The equation of state study in UU collisions at CSR, Lanzhou

The cooling storage ring, to be built at Lanzhou, will be able to deliver heavy ion beams up to uranium up to 0.52 GeV/u. It is expected to make considerable contribution to nuclear EOS study in the high net baryon-density region. With a relativistic transport model, we performed simulations for U+U collisions with different orientations. It is shown that by combining the forward neutron multiplicity and an event-wise elliptic flow selection, it is possible to identify the tip - tip and body - body head-on collisions. The effective identification of these two extreme configurations will allow us to study the EOS at the highest baryon density in the U+U collisions.

Barnacle recurit density, biomass, and reproductive output measured in rocky intertidal habitats in Glasgow Head, on the Atlantic coast of Nova Scotia, Canada

Through a field experiment, we show that a predator has negative nonconsumptive effects (NCEs) on different life-history stages of the same prey species. Shortly before the recruitment season of the barnacle Semibalanus balanoides (May-June), we established experimental cages in rocky intertidal habitats in Nova Scotia, Canada. The cages were used to manipulate the presence and absence of dogwhelks, Nucella lapillus, the main predators of barnacles. At the centre of each cage, we installed a tile where barnacle pelagic larvae could settle and the resulting recruits grow. Mesh prevented caged dogwhelks from accessing the tiles, but allowed waterborne dogwhelk cues to reach the tiles. Results in May indicated that barnacle larvae settled preferentially on tiles from cages without dogwhelks. In November, at the end of the dogwhelk activity period and once the barnacle recruits had grown to adult size, barnacle body mass was lower in the presence of dogwhelks. This limitation may have resulted from a lower barnacle feeding activity with nearby dogwhelks, as found by a previous study. The observed larval and adult responses in barnacles are consistent with attempts to decrease predation risk. November data also indicated that dogwhelk cues limited barnacle reproductive output, a possible consequence of the limited growth of barnacles. Overall, this study suggests that a predator species might influence trait evolution in a prey species through NCEs on different life-history stages.

Light truck aggressivity study - test report 1 - truck-to-car head-on impact tests. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Van crashworthiness and aggressivity study - test report 2: van-to-car head-on impact tests. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Van crashworthiness and aggressivity study. Test report I: van-to-NHTSA fixed test device head-on impact tests. Volume I. Final report.

National Highway Traffic Safety Administration, Washington, D.C.