Skimmers are used to separate the neutrals from the plasma beam,

Skimmers are used to separate the neutrals from the plasma beam, which is guided from the source to the target by a strong axial magnetic field. In this way, the neutrals are prevented to reach the target region. The

neutral flux to the target must be lower than the plasma flux to enable ITER relevant plasma-surface interaction (PSI) this website studies. It is therefore essential to control the neutral gas dynamics. The DSMC method was used to model the expansion of a hot gas in a low pressure vessel where a small discrepancy in shock position was found between the simulations and a well-established empirical formula. Two stage differential pumping was modeled and applied in the linear plasma devices Pilot-PSI and PLEXIS. In Pilot-PSI a factor of 4.5 pressure reduction for H-2 has been demonstrated. Both simulations and experiments showed that the optimum skimmer position depends on the position of the shock and therefore shifts for different gas parameters. The shape of

the skimmer has to be designed such that it has a minimum impact on the shock structure. A too large angle between the skimmer and the forward direction of the gas flow leads to an influence on the expansion find more structure. A pressure increase in front of the skimmer is formed and the flow of the plasma beam becomes obstructed. It has been shown that a skimmer with an angle around 53 degrees gives the best performance. The use of skimmers is implemented in the design of the large linear plasma generator Magnum-PSI. Here, a three stage differentially pumped vacuum selleck compound system is used to reach low enough neutral pressures near the target, opening a door to PSI research in the ITER relevant regime.”
“This study was developed in order to evaluate two alternatives for the control of Listeria monocytogenes in raw bovine meat pieces, both based

on the use of Thymus vulgaris and Rosmarinus officinalis essential oils (EOs). The antilisterial activity of different concentrations of the EOs was tested in vitro using agar dilution and disk volatilization techniques. In addition, L. monocytogenes was inoculated in meat pieces, which were submerged in edible gelatin coatings containing 2% (v/v) EOs or submitted to the vapor of EOs (0.74 mu L.cm(-3)). L. monocytogenes was quantified after one, 48 and 96 hours of storage (7 degrees C). In the in vitro tests, the EO of T. vulgaris presented higher activity. The two options used (edible gelatin coating and vapor activity), in spite of exercising effects with differentiated behaviors, presented antibacterial activity against L. monocytogenes inoculated in raw bovine meat (p < 0.05). Greatest antibacterial activity were obtained in the experiment that used edible coatings containing EOs, at 48 hours of storage reductions in bacterial counts between 1.09 and 1.25 Log CFU.g(-1) were obtained. In the vapor effect experiment, the EO of T.

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