Passive dispersion

Technica, 1988 Wheatley, 1988 Ziomas, 1989). Plume dispersion consists of two phases the gravityslumping and passive dispersion period. Continuous releases with any time-profile and puff releases as of short duration continuous releases are treated using the release category and th r... 

When studying population responses to chemical stress, it may be convenient to make a distinction between internal and external recovery. Internal recovery depends on surviving individuals in the stressed ecosystem or on a reservoir of resting propa-gules (e.g., seeds and ephippia) not affected by the stressor. In contrast, external recovery depends on the immigration of individuals from neighboring ecosystems by active or passive dispersal. 

The key innovation in passive dispersive (as opposed to interferometric) spectrometers introduced recently is the use of a programmable digital spatial light modulator (SLM) to encode spectral information. The most advanced version of SLM currently is a reflective digital micromirror array (DMA). The feasibihty of DMA-based multiplexed spectrometers has been experimentally demonstrated recently. ... 

Mandanas, M.M., Shaffer, W. and Adair, J.H., Aqueous processing and stahilization of manganese zinc ferrite powders via a passivation-dispersion approach, J. Am. Ceram. Soc., 85, 2156, 2002. 

In this section, we have shown how Ay(r) is determined according to the nature of the light-matter interactions and the presence or absence of material resonances. For interactions of the quadrature type, the active processes or the nonresonant passive dispersions, the signal field is always in-phase with respect to the induced polarization, namely A( y(r) = 0. For all remaining passive interactions, where the light-matter interactions are not directly in quadrature in the fields, the signal field must be out-of-phase, Aphase components in the presence of resonance (0< A0y(r) < jtt). 

In nonresonant passive dispersions, in which the light-matter interactions are maximally in quadrature at the polarization level, but there is no material resonance, no energy transfer between the medium and any Fourier component of the field is possible because A< y(r) = 0 (See Eq. (3.4) with "=0). Equation (3.8), however, remains valid for such processes. 

Carbonell, R.G., and S. Whitaker. 1983. Dispersion in pulsed systems. II. Theoretical developments for passive dispersion in porous media. Chem. Eng. Sci. 18 1795-1802. 

Maguire, B. (1963). The passive dispersal of small aquatic organisms and their colonization of isolated bodies of water. Ecological Monographs 33, 161-185. 

The passive dispersal of viable algae and protozoa by an aquatic beetle. Transactions of the American Microscopical Society 87, 443-448. Moore, J. (2005). Revolution of the Space Invaders Darwin and Wallace on the geography of life. In Livingstone, D.N., Withers, C.W.J. (eds.). Geography and Revolution, pp. 106-132. 

The EiE hypothesis assumes that organisms with microscopic size have high passive dispersal rates and consequently are widely distributed (Fenchel and Finlay, 2004). To achieve highly effective dispersal, dormant stages have to survive during dispersal, recover afterwards and be able to establish in the new place. Here, I review the evidence for each of these steps. 

G6mez, A., Adcock, G.I., Lunt, D.H., Carvalho, G.R. (2002b). The interplay between colonisation history and gene flow in passively dispersing zooplankton microsatellite analysis of rotifer resting egg banks. Journal of Evolutionary Biology 15,158-171. 

In its initial phase a dense gas cloud spreads less in the vertical direction than a cloud of neutral density. Yet, the belief that a dense gas cloud therefore migrates further than one of neutral density is not correct. The different mechanism of mixing with air leads to faster spreading especially under stable weather conditions. In the long run the density of a dense gas cloud becomes practically neutral due to mixing with air. A phase of passive dispersion, whose modelling was explained in the preceding section, ensues. 

The behavior of the model in certain limiting conditions could also be considered. For example, for a passive release, does the model give results that are consistent with a simple passive dispersion model ... 

Witlox, H. W. M., and A. Holt. 1999. A Unified Model for Jet, Heavy, and Passive Dispersion Including Droplet Rainout and Re-evaporation, in International Conference and Workshop on Modeling the Consequences of Accidental Releases of Hazardous Materials, San Francisco, September 28-October 1, American Institute of Chemical Engineers, New York, pp. 315-344... 

Passive dispersion The passive regime is described by the partial reflection model, which is a Gaussian-based model that accounts for gravitational settling and deposition effects (Overcamp, 1976). 

When transition to passive dispersion behavior occurs, only H2SO4 aerosol is present in the cloud and some of it is lost on the ground due to deposition and gravitational settling effects (Kapias, 1999 Kapias and Griffiths, 1999a). 

For any reaction in solution, the solvent plays a role that depends on its chemical nature. Some solvents passively disperse the substances into individual molecules. But water is much more active, interacting strongly with the substances and even reacting with them in some cases. Nearly all enviromnental and biological reactions occur in water, so let s focus on how the water molecule interacts with both ionic and covalent solutes. 

After this stage, when the cloud has density equal to the air s, the passive dispersion occurs which is governed by the environmental conditions, mainly by wind and atmospheric stability (TNO, 2005). 

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