Streamers

Crystallization. Acidified aluminum sulfate solutions can be supercooled 10 °C or more below the saturation point. However, once nucleation begins, the crystallization rate is rapid and the supersaturated solution sets up. The onset of nucleation in a gentiy stirred supersaturated solution is marked by the appearance of silky, curling streamers of microscopic nuclei resulting from orientation effects of hydraulic currents on the thin, platelike crystals. Without agitation, nucleation in an acidified solution, in glass tubes, can yield extended crystalline membranes of such thinness to exhibit colors resulting from optical interference. 

The distance between trays Zt should be larger than h, sufficient so that (1) the streamers of dispersed hquid from the holes break up into drops before coalescing into the layer of liqmd on the next plate, (2) the linear velocity of continuous liquid is not greater than that in the down out to avoid excessive entrainment, and (3) the tower may be enterea through handholes or manholes in the sides for cleaning. 

Similar considerations might apply to bulking bmsh (2-6.3) and surface streamer (2-6.6) discharges which propagate across charged surfaces over distances up to about 1 m at source voltages less than 100 kV. 

Leucht-erscheinung, /. luminous phenomenon, -faden, m. luminous filament glow column light streamer. 

Rauch-erzeuger, m. smoke generator or producer. -erzeugung, /. smoke production Aqtxc.) smudging, -fahne,/. smoke streamer, -fang, m. chimney, flue. 

Lastly, dyes can be dispersed by expl charges. These generate colored clouds (about 10x20m) which are formed instantaneously and which have a life expectancy, depending on environmental conditions, from 65—85 seconds, whereas aerial burning of the aforementioned burning type produces streamers about one meter across and which last for about 57-120 seconds... 

Dielectric barrier discharges (DBD) is the case in which a dielectric material is placed on the electrode surfaces. Similar to corona discharges, small-scale electron streamers are formed. In the DBD mode of operation, the threshold electric field... 

The plasma appears in front of the nozzles and shows a flame-like pattern (Figure 12.4b [56]). It consists of streamers, which propagate from the tip of the nozzles to the planar electrodes (Figure 12.4c [57]). The velocity of the streamer head was estimated to about 2.5 x 105m/s [57],... 

Figure 12.4. (A). Schematic drawing of the corona radical shower system 1 - high voltage electrode (pipe with nozzles), 2 - nozzles, 3 - planar ground electrodes (B) Photograph of the discharge in a corona radical shower system with 10 nozzles [56] (C) CCD images of streamers in a corona radical shower system [57] (CCD exposure time 400 ns).

Two-dimensional distributions of ground-state NO were detected by planar laser-induced fluorescence during the process of NO removal in a corona radical shower system in NO/dry air mixtures [57,58], The authors observed that the density of NO molecules decreased not only in the plasma region formed by the corona streamers and the downstream region of the reactor, but also in the upstream region of the reactor. They explained this behaviour by oxidation with ozone, which is transported upstream by electrohydrodynamic flow. 

Kirkpatrick, M.J., Finney, W.C. and Locke, B.R. (2003) Chlorinated organic compound removal by gas phase pulsed streamer corona electrical discharge with reticulated vitreous carbon electrodes, Plasmas and Polymers 8, 165-77. 

Kulikovsky, A.A. (1997) Production of chemically active species in the air by a single positive streamer in a nonuniform field, IEEE Trans. PI. Sci. 25, 439-46. 

Jani, M.A., Takaki, K. and Fujiwara, T. (1999) Streamer polarity dependence of NOx removal by dielectric barrier discharge with a multipoint-to-plane geometry, J. Phys. D Appl. Phys. 32, 2560-7. 

Kanazawa, S., Sumi, T., Shimamoto, S. et al. (2004) Diagnostics of NO oxidation process in a nonthermal plasma reactor Features of DC streamer-corona discharge and NO LIF profile, IEEE Trans. PI. Sci. 32, 25-31. 

Edge of heater ribbon visible at left (2). Vapor streamers from edges of heater ribbons (3). Fluctuating surface temperature. 

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