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Motion defined

The equations of internal motion defined within the local (molecular) fixed coordinate system have to be transformed to the laboratory fixed coordinate system in which all experiments are performed. Thus, introducing Euler s angles, (b, 0, and X, the coordinates of the electrons (e) and nuclei (n) are transformed in the following... [Pg.150]

In a system with strong damping of the concentration motion the concentration oscillations are constrained they follow oscillations in the correlation motion. As compared to the Lotka-Volterra model, where the concentration motion defines essentially the autowave phenomena, in the Lotka model it is less important being the result of the correlation motion. This is why when plotting the results obtained, we focus our main attention on the correlation motion in particular, we discuss in detail oscillations in the reaction rate K(t). [Pg.502]

In Eyring s theory, yielding occurs by stress and temperature-activated jumps of molecular segments (McCrum et al., 1992). The applied stress reduces the activation barrier (AH) and segment motions define an activation volume, V. ... [Pg.374]

As the Reynolds number increases, a wake is formed behind the fluid sphere or ellipsoid [22, 45]. The formation of a wake behind a fluid particle is delayed compared to a solid sphere due to the internal circulation of the gas. The recirculating wake may be completely detached from the fluid sphere. A secondary internal vortex will then not be formed. For smaller particle Reynolds numbers the wake is symmetrical, but as the Reynolds number increases further the vortex sheet breaks down to vortex rings. Further increase of the Re molds number cause the vortex rings to shed asymmetrically, and the drop or bubble will show a rocking motion. This is one of the two types of secondary motion defined. The other is oscillations (shape dilations), and is also thought to be due to the vortex shedding. [Pg.575]

Consider an equilibrium thennodynamic ensemble, say a set of atomic systems characterized by the macroscopic variables T (temperature), Q (volume), andTV (number of particles). Each system in this ensemble contains N atoms whose positions and momenta are assigned according to the distribution function (5.2) subjected to the volume restriction. At some given time each system in this ensemble is in a particular microscopic state that coiTesponds to a point (r, p- ) in phase space. As the system evolves in time such a point moves according to the Newton equations of motion, defining what we call a phase space trajectory (see Section 1.2.2). The ensemble coiTesponds to a set of such trajectories, defined by their starting point and by the Newton equations. Due to the uniqueness of solutions of the Newton s equations, these trajectories do not intersect with themselves or with each other. [Pg.177]

Li = mniaf where ni is the inner mean angular motion defined in (71)... [Pg.125]

This equation apparently contradicts the statements made that r is the heliocentric radius vector and pi is the barycentric linear momentum. However, this only means that the variation of rj in the reference Kep-lerian motion is not the actual relative velocity of the ith body but Pi/Pi-This means that, at variance with other formulations, the Keplerian motions defined by equations (12) are not tangent to the actual motions. To distinguish them from heliocentric osculating , when necessary, we will use the term heliocentric canonical . [Pg.260]

We now introduce the angle and action variables wk°, 3k° of the undisturbed motion, and consider the Hamiltonian function of the perturbed motion defined in terms of them. They are still canonical co-ordinates, but, in general, they are no longer angle and action variables in fact, it is evident from the canonical equations... [Pg.250]

In any neighbourhood of each of the motions defined by w °— and there are, however, motions of rotation and libration for which w ° takes values widely different from J or f. For w °= or the motion with a definite phase relation is therefore unstable, in the mechanical sense of the word. In this case the motions w °=J and are also energetically unstable, inasmuch as H is then a maximum. We shall also meet with cases, however, where the mechanically stable motion is energetically unstable. [Pg.268]

It should be noted that when we say three intermolecular energy transfer mechanisms, it does not mean that they are isolated from each other. These channels work collaboratively. For example, it has been suggested that the V-T/V-R (collision) energy transfer mechanism is more effective when the solute and solvent molecules are held close by electrostatic interaction or hydrogen bonding [70,71]. In addition, it has been reported that librational motions, defined as the hydrogen bond-hindered water molecule rotational motions with frequency 600-950cm, play a... [Pg.208]

In quantum chemistry the speeifie method was consecrated as Bom-Oppenheimer approximation that separate the electronic-nuclear system and problem in two smaller parametrieally linked subsystems associated with an electronic motion, defined by equations... [Pg.421]

At the core of a DES lies the concept of discrete event and the assumption that the state-space of the system, denoted by /, is a discrete set. For practical reasons, we can furthermore assume that x is composed of a finite number of states. In particular, any DES can move from a state x to a new state x . We say that this motion defines a state transition. In the DES context, the term event conceptualizes the occurrence of an action e that initiates the state transition from X to x . We say that the event e labels the transition from X to x and we write x x For example, the opening of a valve indicates the system s transition from state the valve is closed Xo the state the valve is open that is associated with the initiation of the command open valve (event) as shown in Figure 1. A state that is not associated with the initiation of any event is called a dead-lock state. [Pg.1999]

Figure 3.15. An element of the fluid surface showing the five possible surface motions defined by Goodrich (1981). Figure 3.15. An element of the fluid surface showing the five possible surface motions defined by Goodrich (1981).
In order to solve the equations of motions defined above, the forces on each of the ions must be defined. This can be done by using the Hellman-Feynman theorem, whereby the force is defined as the derivative of the total energy with respect to the positions of the ions ... [Pg.446]

Rotational and translational motions defined between two rigid bodies (femur and tibia bones) and necessary three-dimensional joint coordinate system can be seen be in Figure 25.2. [Pg.529]

Then we can obtain the following Eulerian form of the equation of motion defined in the current deformed body ... [Pg.33]

These equations of motion define the time evolution of both microscopic and macroscopic variables Coordinates and momenta can be written for each nucleus or, by well-known transformations, for the translation, rotation and vibration of each molecule. In addition to Hamilton s equations, the laws of continuum mechanics place constraints on the time-dependence of macroscopic conserved quantity such as number, momentum and energy density. For example, if the macroscopic number density of particles at point jr is denoted by p( ,t), one has a microscopic definition... [Pg.112]


See other pages where Motion defined is mentioned: [Pg.79]    [Pg.50]    [Pg.375]    [Pg.497]    [Pg.120]    [Pg.41]    [Pg.163]    [Pg.345]    [Pg.182]    [Pg.316]    [Pg.287]    [Pg.63]    [Pg.71]    [Pg.163]    [Pg.79]    [Pg.1120]    [Pg.571]    [Pg.101]    [Pg.4]    [Pg.47]    [Pg.34]    [Pg.226]    [Pg.71]    [Pg.30]    [Pg.92]    [Pg.606]    [Pg.31]    [Pg.192]    [Pg.220]   
See also in sourсe #XX -- [ Pg.258 ]




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