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Chapter Eight Binary Particle Collision Processes This chapter considers binary particle collision processes, including 1. Coulomb interactions and ionization losses; 2. bremsstrahlung; 3. secondary nuclear production and spallation; 4. thermal electron-positron annihilation radiation; and 5. nuclear γ -ray line radiation. The rate of thermalization and energy transfer between ionic and lep- tonic species is determined in the first approximation by the rate of binary collision processes. In a magnetized plasma, collective effects may be as important as binary

The action of cationic polyelectrolytes used for the fixation of dissolved and colloidal substances Lars Wdgberg, SCA Research AB, Sundsvall, Sweden Lars Odberg, STFI, Stockholm, Sweden solved and colloidal material, and in the US the use Keywords: Polyelectrolytes, Colloids, Cationic com- pounds, Synthetic polymers, Thermomechanical pulps, Ex- of alum in newsprint production is still very common. tractives, Flocculation, Particle collisions. Studies of the colloidal stability of the dispersions produced in the pulping process have however shown SUMMARY

Particle deposition on pulp fibers The influence of added chemicals Theo G. M. van de Ven, Paprican and Department of Chemistry, Pulp and Paper Research Centre, McGill University, Montreal, Canada Keywords: Particle collisions, Retention aids, Filler retention, Kinetics, Flocculation, Deposition, Chemicals, Particles, Fib- ers, Fines, Fillers, Pulps. SUMMARY: Many chemicals added to a papermaking suspen- sion are of a polymeric nature and affect the interactions be- tween fibers, fines and fillers. Optimization of fines and fillers retention is

Screened Collision-Induced Quantum Interference in Collisional Plasmas Sang-Chul Naa and Young-Dae Junga,b a Department of Applied Physics, Hanyang University, Ansan, Kyunggi-Do 426-791, South Korea b Atomic and Molecular Data Research Center, National Institute for Fusion Science, Toki, Gifu, 509-5292, Japan Reprint requests to Y.-D. J.; E-mail: ydjung@hanyang.ac.kr Z. Naturforsch. 64a, 233 – 236 (2009); received April 8, 2008 / revised November 11, 2008 The effects of neutral particle collisions on the quantum interference in electron-electron collisions are

2 ⁢ ( t ) ) {\eta(t)=(\xi_{1}(t),\xi_{2}(t))} . Then we consider τ ( k 1 , k 2 ) ⁢ ( z ) = inf ⁡ { t ≥ 0 : Δ ⁢ ( t ) = 0 , η ⁢ ( 0 ) = ( k 1 , k 2 ) } , k j ∈ { 0 , 1 } , \tau_{(k_{1},k_{2})}(z)=\inf\bigl{\{}t\geq 0:\Delta(t)=0,\,\eta(0)=(k_{1},k_{2% })\big{\}},\quad k_{j}\in\{0,1\}, as the instant of the first particle collision assuming η ⁢ ( 0 ) = ( k 1 , k 2 ) {\eta(0)=(k_{1},k_{2})} . Our purpose in this section is to calculate the probability distribution of the random variable τ ( k 1 , k 2 ) ⁢ ( z ) {\tau_{(k_{1},k_{2})}(z)} . We will calculate the

J. Non-Equilib. Thermodyn. 35 (2010), 125–143 DOI 10.1515/JNETDY.2010.008 © de Gruyter 2010 The compound piston: resolution of a thermodynamic controversy by means of kinetic theory David Sands and Jeremy Dunning-Davies Communicated by W. Muschik, Berlin, Germany Abstract A numerical model of a hard-sphere fluid on either side of a compound piston shows that damping occurs naturally without invoking extraneous mechanisms such as friction. Inter-particle collisions are identified as be- ing responsible. Whereas only the component of particle momentum in the

/3},$$ (12) F N = m g + m v Δ t $${F}_{N}=mg+\text{m}\frac{v}{{\Delta}t}$$ Where K S is the thermal conductivity, E is the Young’s modulus of the particle, and r is the particle radius ( Shao et al. 2020 ). 2.3.3 Particle–particle collision heat transfer Particle–particle collision heat conduction is based on the collision criteria and has been described in motion models. When a collision occurs, the heat exchange between particles can be described as ( Yu et al. 2018 ) (13) Q p 1 p 2 = H C ⋅ Δ T p i p j ⋅ Δ t , $${\text{Q}}_{p1p2}={\text{H}}_{C}\cdot {\Delta

1 Introduction Gas–particle horizontal channel turbulent flows have widely been applied in many industrial and chemical processes, such as coal energy conversation system, catalytic cracking of petroleum industry, solid particles drying, particle separation, pneumatic conveying, etc. Due to the complex effects of turbulent diffusions, particle inertia, particle collisions and four-way coupling interactions among gas–particle and particle–particle, it is very difficult to get a better understanding of the particle–particle interactions and its effects on two

critical velocity with the estimated inter-particle collision velocities within an industrial-scale reactor, the agglomeration tendency of coke particles is determined within fluid cokers. The results show that at low temperature regions (T=400 ◦C), there is no agglom- eration tendency; however, at high coking temperatures (T=503 and 530 ◦C), sub- stantial agglomeration tendency is expected. It is also found that the number of coke particles constituting an agglomerate could be as high as a few hundreds. KEYWORDS: fluid coker, agglomeration, coke particles, bitumen

References Auton T. R. (1987) The lift force on a spherical body in a rotational flow. J. Fluid Mech., 183, 199-218. Bagnold R. A. (1956) The flow of cohesionless grains in fluids, Phil. Trans. R. Soc. London A, 249, 235-297. Bialik R. (2011) Particle-particle collision in Lagrangian modeling of saltating grains, Journal of Hydraulic Research, 49(1), 23-31. Bialik R. (2010) Modeling of saltating grains in river flows and transport of bed load sediment. Ph.D. Thesis (in Polish). Coleman N. L. (1967) A theoretical and experimental study of drag and lift forces