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Propagation coordination

The LFV integration method propagates coordinates and momenta on the basis of the equation of motion (5) by the following relations... [Pg.336]

Usually, free-radical domino processes are characterized by a sequence of intramolecular steps, the overall propagation coordinate being unimolecular (excluding initiation and termination steps) (Scheme 3.1) [1],... [Pg.219]

Substitution into Equation 4 and integration over the propagation coordinate gives (15-17)... [Pg.126]

The starting point is Maxwell s equations. We consider a non-magnetic medium (/i = fj,o) with a linear permittivity e(u>, x, y) that doesn t depend on the propagation coordinate z. [Pg.255]

Introduction. We have, so far, considered ionic propagation, coordination catalysis, and the step reactions of a pol37mer terminus as techniques for the preparation of block copol3nners. Free radical polymerization may also be utilized by application of one of several chemical manipulations. For example, block copolymers may be prepared by coupling macroradicals, or by generating new radicals in the presence of a second monomer by photolytic or mechanical degradation. As an alternate, difunctional initiators may be employed. [Pg.94]

In order to answer this question we have used the complex adiabatic approach [8]. First the complex resonance potential energy surfaces (PES) were calculated as a function of the slow coordinate (which is perpendicular to the propagation coordinate). Then, assuming that the electron scattering proceeds via a single PES, the transition probability amplitude, t E), was calculated. [Pg.328]

The two-dimensional QD model Hamiltonian, where x is the propagation coordinate, is given by... [Pg.329]

In the first section, the potential energy channel connecting reactant and product arrangements is cut into several sectors. On the one-dimensional cuts of the potential energy channels taken at a fixed value (the sector midpoint) of the propagation coordinate vibrational eigenfunctions and eigenvalues as well as other quantities independent from both the... [Pg.276]

For a sound wave propagating in porous textiles, the porous gas-filled medium is often treated as an equivalent uniform medium for analysis purposes, so a propagation factor can be used to describe the dependence of the propagating wave on time t and the propagation coordinate x (Bies and Hansen, 2009). Here, m=Inf is. the angular frequency and /is the wave frequency. The propagation constant y is also called the propagation coefficient, which is a complex number and can be expressed as ... [Pg.105]

Stage 1 Propagating Coordination Command. In Stage I, the coordination episode begins with the human supervisor providing the command. This command does not have to be conununicated to a specific collective member but instead can be provided to any robot. Together with the command is information about which robots have been rendered inactive and which ones are still active. The robot which receives the coordination command from the human supervisor propagates the command (and the relevant information about which robots are still active) to the other active members of the robot collective. [Pg.172]

After propagation into the back focal plane of tire objective lens, the scattered electron wave can be expressed in tenns of the spatial frequency coordinates k as... [Pg.1637]

We consider the computation of a trajectory —X t), where X t) is a vector of variables that evolve in time —f. The vector includes all the coordinates of the particles in the system and may include the velocities as well. Unless specifically indicated otherwise X (t) includes coordinates only. The usual way in which such vectors are propagated numerically in time is via a sequence of short time solutions to a differential equation. One of the differential equations of prime concern is the Newton s equation of motion ... [Pg.265]

Note that, in loeal eoordinates. Step 2 is equivalent to integrating the equations (13). Thus, Step 2 can either be performed in loeal or in eartesian coordinates. We consider two different implicit methods for this purpose, namely, the midpoint method and the energy conserving method (6) which, in this example, coineides with the method (7) (because the V term appearing in (6) and (7) for q = qi — q2 is quadratie here). These methods are applied to the formulation in cartesian and in local coordinates and the properties of the resulting propagation maps are discussed next. [Pg.289]

Propagate by harmonic part of Hq for the time Arjl. This corresponds to the rotation of internal normal coordinates, P( and Q[, in the phase space by the corresponding vibrational frequency Ui... [Pg.339]

These are addition polymerizations in which chain growth is propagated through an active center. The latter could be a free radical or an ion we shall see that coordinate intermediates is the more usual case. [Pg.473]

The monometallic mechanism is illustrated in Fig. 7.13a. It involves the monomer coordinating with an alkylated titanium atom. The insertion of the monomer into the titanium-carbon bond propagates the chain. As shown in... [Pg.491]

The bimetallic mechanism is illustrated in Fig. 7.13b the bimetallic active center is the distinguishing feature of this mechanism. The precise distribution of halides and alkyls is not spelled out because of the exchanges described by reaction (7.Q). An alkyl bridge is assumed based on observations of other organometallic compounds. The pi coordination of the olefin with the titanium is followed by insertion of the monomer into the bridge to propagate the reaction. [Pg.493]

Epichlorohydrin Elastomers without AGE. Polymerization on a commercial scale is done as either a solution or slurry process at 40—130°C in an aromatic, ahphatic, or ether solvent. Typical solvents are toluene, benzene, heptane, and diethyl ether. Trialkylaluniinum-water and triaLkylaluminum—water—acetylacetone catalysts are employed. A cationic, coordination mechanism is proposed for chain propagation. The product is isolated by steam coagulation. Polymerization is done as a continuous process in which the solvent, catalyst, and monomer are fed to a back-mixed reactor. Pinal product composition of ECH—EO is determined by careful control of the unreacted, or background, monomer in the reactor. In the manufacture of copolymers, the relative reactivity ratios must be considered. The reactivity ratio of EO to ECH has been estimated to be approximately 7 (35—37). [Pg.555]

For a shock wave in a solid, the analogous picture is shown schematically in Fig. 2.6(a). Consider a compression wave on which there are two small compressional disturbances, one ahead of the other. The first wavelet moves with respect to its surroundings at the local sound speed of Aj, which depends on the pressure at that point. Since the medium through which it is propagating is moving with respect to stationary coordinates at a particle velocity Uj, the actual speed of the disturbance in the laboratory reference frame is Aj - -Ui- Similarly, the second disturbance advances at fl2 + 2- Thus the second wavelet overtakes the first, since both sound speed and particle velocity increase with pressure. Just as a shallow water wave steepens, so does the shock. Unlike the surf, a shock wave is not subject to gravitational instabilities, so there is no way for it to overturn. [Pg.18]

We assume that in (4.38) and (4.39), all velocities are measured with respect to the same coordinate system (at rest in the laboratory) and the particle velocity is normal to the shock front. When a plane shock wave propagates from one material into another the pressure (stress) and particle velocity across the interface are continuous. Therefore, the pressure-particle velocity plane representation proves a convenient framework from which to describe the plane Impact of a gun- or explosive-accelerated flyer plate with a sample target. Also of importance (and discussed below) is the interaction of plane shock waves with a free surface or higher- or lower-impedance media. [Pg.84]

The shock-change equation is the relationship between derivatives of quantities in terms of x and t (or X and t) and derivatives of variables following the shock front, which moves with speed U into undisturbed material at rest. The planar shock front is assumed to be propagating in the x (Eulerian spatial coordinate) or X (Lagrangian spatial coordinate) direction, p dx = dX. [Pg.261]


See other pages where Propagation coordination is mentioned: [Pg.479]    [Pg.280]    [Pg.97]    [Pg.116]    [Pg.274]    [Pg.274]    [Pg.105]    [Pg.169]    [Pg.170]    [Pg.479]    [Pg.280]    [Pg.97]    [Pg.116]    [Pg.274]    [Pg.274]    [Pg.105]    [Pg.169]    [Pg.170]    [Pg.6]    [Pg.244]    [Pg.250]    [Pg.1072]    [Pg.2277]    [Pg.2297]    [Pg.2304]    [Pg.2870]    [Pg.46]    [Pg.259]    [Pg.266]    [Pg.378]    [Pg.6]    [Pg.271]    [Pg.236]    [Pg.411]    [Pg.342]    [Pg.352]    [Pg.438]    [Pg.101]   
See also in sourсe #XX -- [ Pg.339 , Pg.344 ]

See also in sourсe #XX -- [ Pg.339 , Pg.344 ]




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Cationic coordination polymerization propagation

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