Absorption of particles from a melt by the surface of a bubble of variable size—Part III
✍ Scribed by V.N Dorovsky
- Publisher
- Elsevier Science
- Year
- 1999
- Tongue
- English
- Weight
- 689 KB
- Volume
- 37
- Category
- Article
- ISSN
- 0898-1221
No coin nor oath required. For personal study only.
✦ Synopsis
The process of absorption of particles by the surface of a bubble in a melt is considered. The particles are also in the melt. Besides the particles, the melt also contains a surfactant which is adsorbed on the particles and on the surface of the bubble. There occurs an interaction which causes the particles to move towards the surface of the bubble. It is shown that during the movement of the bubble boundary the absorption of particles is determined by the parameter = 16m2eco/(Dwo(2k2)R which depends on the velocity of motion of the bubble boundary and on a parameter which does not depend on the velocity of motion of the boundary eco/D. The parameters are as follows: m is the mass of a particle is the area of a particle k is a coefficient which determines the adsorption properties of the particle surface D is the diffusion coefficient of the surfactant in the melt
a is a characteristic size of a particle
• = (kvTRg/rn
T is the temperature Rg is the gas constant v is the characteristic time of Stokes' attenuation of a particle in the melt.
At small values of A the solution is close to that of the previous investigation [1], if a small correction to the flux of particles onto the bubble surface is introduced. At large values of A and positive velocities of the bubble-melt interface, a characteristic flux ,/~Jo can be distinguished which characterizes the running of the boundary on particles. It turns out that at eco/D > 1, the flux TWo > /~Jo. If the condition eco/D < 1 is fulfilled, the flux of particles onto the bubble surface Wo </~Jo.
In both cases the maximal value of the flux is on the bubble boundary.
When the velocities of the boundary are negative, an interesting result is obtained at A > 1.
Here we consider two cases. At eco/D < 1 the flux is maximal near the surface of the bubble and increases exponentially in time. Strong absorption of particles in the area near the bubble boundary takes place. At eco/D > 1 an N-wave is formed: the flux is maximum near the bubble boundary, and behind this area there is a trough. All this construction moves towards the bubble surface. We can say that an extremely strong dependence of the absorption regimes on parameters of the system and the velocity of the interface is a characteristic feature of the particle absorption at the moving interface. ~
📜 SIMILAR VOLUMES
The extinction of radiation in suspensions is traditionally described by the Bouger-Lambert-Beer law (BLBL). Based on a quasicontinuum approach, the BLBL does not account for the discrete nature of particles or their spatial extension and arrangement. If an extinction measurement is made with a high
Photosystem I particles containing 30-40 chlorophyll a molecules per primary electron donor P700 were subjected to 1.5 l~S low density laser flashes at 610 nm resulting in excitation of the antenna chlorophyll a molecules followed by energy transfer to P700 and subsequent oxidation of P700. Absorban