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Particle states 396 Subject

In the absence of intermolecular reactions, the particles are subjected just to excited-state decay, represented by the following matrix equations... [Pg.154]

The CCN behavior of ambient particles can be measured by drawing an air sample into an instrument in which the particles are subjected to a known supersaturation, a so-called CCN counter (Nenes et al. 2001). If the size distribution and chemical composition of the ambient particles are simultaneously measured, then the measured CCN behavior can be compared to that predicted by Kohler theory on the basis of their size and composition. Such a comparison can be termed a CCN closure, that is, an assessment of the extent to which measured CCN activation can be predicted theoretically [see, for example, VanReken et al. (2003), Ghan et al. (2006), and Rissman et al. (2006)]. The next level of evaluation is an aerosol-cloud drop closure, in which a cloud parcel model, which predicts cloud drop concentration using observed ambient aerosol concentration, size distribution, cloud updraft velocity, and thermodynamic state, is evaluated against direct airborne measurements of cloud droplet number concentration as a function of altitude above cloud base. The predicted activation behavior can also be evaluated by independent measurements by a CCN instrument on board the aircraft. Such an aerosol-cloud drop closure was carried out by Conant et al. (2004) for warm cumulus clouds in Florida. [Pg.793]

The next term, EX, is positive for all the molecular systems of interest for liquids. The name makes reference to the exchange of electrons between A and B. This contribution to AE is sometimes called repulsion (REP) to emphasize the main effect this contribution describes. It is a true quantum mechanical effect, related to the antisymmetry of the electronic wave function of the dimer, or, if one prefers, to the Pauli exclusion principle. Actually these are two ways of expressing the same concept. Particles with a half integer value of the spin, like electrons, are subjected to the Pauli exclusion principle, which states that two particles of this type cannot be described by the same set of values of the characterizing parameters. Such particles are subjected to a special quantum version of the statistics, the Fermi-Dirac statistics, and they are called fermions. Identical fermions have to be described with an antisymmetric wave function the opposite also holds identical particles described by an... [Pg.428]

If there is nucleation, Eq. (7.3.6) must be subject to the boundary condition (7.3.3). The foregoing equation is significantly different from the population balance equation because of the presence of the second-order product density on the right-hand side. The population balance equation can be obtained from Eq. (7.3.6) only under the assumption of statistical independence of particle states in each pair, viz.. [Pg.304]

A particle is subject to the potential energy V = + by + cz - If its ground-state energy... [Pg.434]

Recently GulfTex Environmental Services of Texas, United States have developed a new nonthermal dryer called Pulverizing Air Dryer (PAD). This dryer does not use heat but can reduce moisture content from 80 to as low as 10% depending on the biomass. The PAD technology uses high-velocity air streams to accelerate and then collide against the particle streams subjected... [Pg.1033]

Initially, the concentiaJUon of dissobteilgas in the eddy is internally the eddy is considered to be stagnant. When the eddy is expoited to the. gas.aL,the surface, the concentration in the Jiq.ui(lat the gas-liquid surface is Cj which may be taken as the eqnilibrium solubility of the gas in the liquid. During the timeuti, the hquid particle is subject to unsteady-state.diffusion or penetration of solute in the z direction, and, as an approximation, Eq. (2.18) may be applied ... [Pg.61]

We will demonstrate the variational derivation of single-particle states in the case of the Hartree approximation, where the energy is given by Eq. (2.10), starting with the many-body wavefunction of Eq. (2.9). We assume that this state is a stationary state of the system, so that any variation in the wavefunction will give a zero variation in the energy (this is equivalent to the statement that the derivative of a function at an extremum is zero). We can take the variation in the wavefunction to be of the form I, subject to the constraint that ( = 1, which can be taken into account by... [Pg.46]

The optimization of the Haitree-Fock wave function may be carried out using any of the standard techniques of numerical analysis. However, for many purposes, it is better to use an alternative scheme, which mote directly reflects the physical contents of the Hartree-Fock state. Thus, from the discussion in Section S.l, we recall that an antisymmetric product of spin orbitals represents a state where each electron behaves as an independent particle (but subject to Fermi correlation as discussed in Section S.2.8). This observation suggests that the optimal determinant - that is, the Hartree-Fock determinant in (5.4.3) - may be found by solving a set of effective one-electron Schrbdinger equations for the spin orbitals. Such an approach is indeed possible the effective one-electron Schrddinger equations are called the Hartree-Fock equations and the associated Hamiltonian is the Fock operator... [Pg.169]

Shapes of the ground- and first tln-ee excited-state wavefiinctions are shown in figure AT 1.1 for a particle in one dimension subject to the potential V = which corresponds to the case where the force acting on the... [Pg.17]

The main conclusion which can be drawn from the results presented above is that dimerization of particles in a Lennard-Jones fluid leads to a stronger depletion of the proflles close to the wall, compared to a nonassociating fluid. On the basis of the calculations performed so far, it is difficult to conclude whether the second-order theory provides a correct description of the drying transition. An unequivocal solution of this problem would require massive calculations, including computer simulations. Also, it would be necessary to obtain an accurate equation of state for the bulk fluid. These problems are the subject of our studies at present. [Pg.204]

The energy and many other properties of the particle can be obtained by solving the Schrfldinger equation for P, subject to the appropriate boundary conditions. Many different wavefunctions are solutions to it, corresponding to different stationary states of the system. [Pg.253]


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