Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Correlation of movements

The main conclusion drawn from the MD simulations is that the proteins are highly flexible. The parts of the proteins that have high B-factors in the crystal structure also show great flexibility in the dynamics. The same regions are flexible in both runs, but the internal correlations of movements differ. This is reflected in the CPCA score plot the snapshots of each of the two CYP2C9 runs and the X-ray structures showed up in a different quadrant and did not overlap at any time point of the simulation. Thus, the molecular dynamics simulations cover a different CPCA space from the crystal structures with and without substrate bound, independent of the different starting structures. [Pg.68]

For diffusion in a porous material with randomly oriented pores, the diffusion process is often assumed to be random as well. Thus, independence of pore to pore transit rates is an important assumption in the analysis of Pismen discussed above. Since the pore structure is fixed, however, this assumption is not necessarily correct. In the simplest case, consider one dimensional diffusion in a continuum and In a material with fixed porous geometry [26]. For a random walk in a continuum, the diffusing molecule loses all history at each step. The molecule moves either to the left or to the right at each step both events have probability 1/2. All possible coordinate points in the material are accessible. In a porous material the medium as well as the molecule is random, but the geometry of the material is fixed. For diffusion in a porous material, the molecular movement is no longer completely random, but is determined by the fixed geometry of the porous material. In fact, movement of molecules on a onedimensional lattice is completely deterministic. For materials of higher dimension, correlation of movement between pores in the medium must be considered [27]. [Pg.178]

The optimum values of die oq and a coefficients are determined by the variational procedure. The HF wave function constrains both electrons to move in the same bonding orbital. By allowing the doubly excited state to enter the wave function, the electrons can better avoid each other, as the antibonding MO now is also available. The antibonding MO has a nodal plane (where opposite sides of this plane. This left-right correlation is a molecular equivalent of the atomic radial correlation discussed in Section 5.2. [Pg.111]

The second axiom, which is reminiscent of Mach s principle, also contains the seeds of Leibniz s Monads [reschQl]. All is process. That is to say, there is no thing in the universe. Things, objects, entities, are abstractions of what is relatively constant from a process of movement and transformation. They are like the shapes that children like to see in the clouds. The Einstein-Podolsky-Rosen correlations (see section 12.7.1) remind us that what we empirically accept as fundamental particles - electrons, atoms, molecules, etc. - actually never exist in total isolation. Moreover, recalling von Neumann s uniqueness theorem for canonical commutation relations (which asserts that for locally compact phase spaces all Hilbert-space representations of the canonical commutation relations are physically equivalent), we note that for systems with non-locally-compact phase spaces, the uniqueness theorem fails, and therefore there must be infinitely many physically inequivalent and... [Pg.699]

The good correlation of the results of vapor diffusion and leaching experiments for butylate, alachlor, and metolachlor with their physical properties has given support to the value of physical property measurements to predict pesticide movement in the soil. [Pg.244]

Photon correlation spectroscopy (PCS) has been used extensively for the sizing of submicrometer particles and is now the accepted technique in most sizing determinations. PCS is based on the Brownian motion that colloidal particles undergo, where they are in constant, random motion due to the bombardment of solvent (or gas) molecules surrounding them. The time dependence of the fluctuations in intensity of scattered light from particles undergoing Brownian motion is a function of the size of the particles. Smaller particles move more rapidly than larger ones and the amount of movement is defined by the diffusion coefficient or translational diffusion coefficient, which can be related to size by the Stokes-Einstein equation, as described by... [Pg.8]

Other bridges, and the conformational interconversion must be more or less concerted (125). For additional examples of correlated intramolecular movements in molecules having polymethylene bridges, see ref. 127. [Pg.135]

Flux Rates We use the term flux to describe the movement of material. Flux rate is then the quantity of material moved por unit time. In the literature we find rates quoted in different time units, sometimes seconds, sometimes minutes, or hours, or days. In particular, flux rates are sometimes presented in pg/cm2-day and sometimes in fg/cm2-sec. We can simplify this a bit by normalizing these to cm2. Thus, Table 1.9 provides a correlation of the rates. [Pg.23]

Correlation effects have already been mentioned a number of times. Let us discuss them here in more detail. In the Hartree-Fock approach (to be more exact, in its single-configuration version, which we have been considering so far) it is assumed that each electron in an atom is orbiting independently in the central field of the nucleus and of the remaining electrons (one-particle approach). However, this is not exactly so. There exist effects, usually fairly small, of their correlated, consistent movement, causing the so-called correlation energy. [Pg.346]

However, beyond this overt similarity, there are differences. For example, Covalon by the nature of covalency would have to operate under a much more stringent correlation than that existing in the Frohlich s model between one paired n-electron and all other such pairs along the chain. This is a natural consequence of distortion in the alternating single double bonds. This treatment also differs from that of self-consistent field treatment [19] of a linear chain and that of Little [20] in our inclusion of bond vibration. Covalon also differs from polaron treatments [21] in the consideration of the movement of spin-paired correlated electrons in a covalent bond, instead of movement of spin-uncorrelated electrons in the zeroth order. [Pg.77]

ED,sp is the dispersion energy which is due to the correlation of electron movements of host and guest. [Pg.72]


See other pages where Correlation of movements is mentioned: [Pg.40]    [Pg.349]    [Pg.40]    [Pg.349]    [Pg.1029]    [Pg.178]    [Pg.133]    [Pg.184]    [Pg.205]    [Pg.371]    [Pg.241]    [Pg.51]    [Pg.105]    [Pg.242]    [Pg.412]    [Pg.80]    [Pg.272]    [Pg.186]    [Pg.295]    [Pg.25]    [Pg.63]    [Pg.511]    [Pg.146]    [Pg.293]    [Pg.189]    [Pg.165]    [Pg.436]    [Pg.396]    [Pg.79]    [Pg.235]    [Pg.373]    [Pg.291]    [Pg.104]    [Pg.101]    [Pg.162]    [Pg.113]    [Pg.143]    [Pg.258]    [Pg.74]    [Pg.131]   


SEARCH



Correlation Spectroscopy of Microbe Movements

Of Movement

© 2024 chempedia.info