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External coordinate

The area under the curve of deformation in the coordinates external load F is the deflection/with consideration for weight of the sample is a full energy consumption to fracture of the SPC sample Wc. [Pg.144]

The configuration of the nuclei of the total system can be defined by a set of coordinates given by vector R. We divide the whole system into the interacting subsystems ( molecules ) A, B,C,... with their intemal geometries (configurations of the nuclei) defined by Ra, Rfi, Rc, and the fixed numbers of electrons Na, Nb,, Nc, , respectively. The rest of the coordinates ( external ) that determine the intermolecular distances and the orientations of the molecules in a global coordinate system will be denoted as R j ... [Pg.797]

During emergencies within TA-V, the SNL/NM IC established by the ICS and the TA-V duty EMSUP established by the TA-V EPP share mutually supporting roles. Upon arrival at TA-V, the SNL/NM IC normally conducts or coordinates all communications through the ICS prior to that, the TA-V EMSUP coordinates external communications through the TA-V Emergency team s External Communicator. [Pg.347]

The limitations of a purely self-regulatory system thus necessitate a degree of coordinated external oversight HSE was created by s. 10 of the HSWA 1974 as a unified central inspectorate with powers to enforce the obligations imposed by that Act (Dawson et al. 1988 11 Hutter... [Pg.116]

OE Governance describes the entity that will oversee OE systems design, coordinate external assessments and monitor implementation and snpport organization. There are two levels of governance local governance at the business line, administrative or department level and corporate OE governance at the execntive... [Pg.170]

In addition, there could be a mechanical or electromagnetic interaction of a system with an external entity which may do work on an otherwise isolated system. Such a contact with a work source can be represented by the Hamiltonian U p, q, x) where x is the coordinate (for example, the position of a piston in a box containing a gas, or the magnetic moment if an external magnetic field is present, or the electric dipole moment in the presence of an external electric field) describing the interaction between the system and the external work source. Then the force, canonically conjugate to x, which the system exerts on the outside world is... [Pg.395]

Kramers solution of the barrier crossing problem [45] is discussed at length in chapter A3.8 dealing with condensed-phase reaction dynamics. As the starting point to derive its simplest version one may use the Langevin equation, a stochastic differential equation for the time evolution of a slow variable, the reaction coordinate r, subject to a rapidly statistically fluctuating force F caused by microscopic solute-solvent interactions under the influence of an external force field generated by the PES F for the reaction... [Pg.848]

Suppose that x [Q)) is the adiabatic eigenstate of the Hamiltonian H[q]Q), dependent on internal variables q (the electronic coordinates in molecular contexts), and parameterized by external coordinates Q (the nuclear coordinates). Since x Q)) must satisfy... [Pg.8]

Now the Lagrangean associated with the nuclear motion is not invariant under a local gauge transformation. Eor this to be the case, the Lagrangean needs to include also an interaction field. This field can be represented either as a vector field (actually a four-vector, familiar from electromagnetism), or as a tensorial, YM type field. Whatever the form of the field, there are always two parts to it. First, the field induced by the nuclear motion itself and second, an externally induced field, actually produced by some other particles E, R, which are not part of the original formalism. (At our convenience, we could include these and then these would be part of the extended coordinates r, R. The procedure would then result in the appearance of a potential interaction, but not having the field. ) At a first glance, the field (whether induced internally... [Pg.151]

Now, consider the case of spinless particles not subject to external electronic and magnetic fields. We may now choose the unitai7 operator U as the unit operator, that is, T = K. For the coordinate and momentum operators, one then obtains... [Pg.616]

The different internal and external file formats make it necessary to have programs which convert one format into another. One of the first conversion programs for chemical structure information was Babel (around 1992). It supports almost 50 data formats for input and output of chemical structure information [61]. CLIFF is another file format converter based on the CACTVS technology and which supports nearly the same number of file formats [29]. In contrast to Babel, the program is more comprehensive it is able to convert chemical reaction information, and can calculate missing atom coordinates [29]. [Pg.46]

However, it is common practice to sample an isothermal isobaric ensemble NPT, constant pressure and constant temperature), which normally reflects standard laboratory conditions well. Similarly to temperature control, the system is coupled to an external bath with the desired target pressure Pq. By rescaling the dimensions of the periodic box and the atomic coordinates by the factor // at each integration step At according to Eq. (46), the volume of the box and the forces of the solvent molecules acting on the box walls are adjusted. [Pg.368]

Figure 4-2 Two Masses Vibrating Harmonically with Respect to their Center of Mass. The center of mass may be stationary or moving with respect to an external coordinate system. Figure 4-2 Two Masses Vibrating Harmonically with Respect to their Center of Mass. The center of mass may be stationary or moving with respect to an external coordinate system.
Copper(I) tends towards a tetrahedral coordination geometry in complexes. With 2,2 -bipyr-idine as a chelate ligand a distorted tetrahedral coordination with almost orthogonal ligands results. 2,2 -Bipyridine oligomers with flexible 6,6 -links therefore form double helices with two 2,2 -bipyridine units per copper(I) ion (J. M. Lehn, 1987,1988). J. M. Lehn (1990 U. Koert, 1990) has also prepared such helicates with nucleosides, e.g., thymidine, covalently attached to suitable spacers to obtain water-soluble double helix complexes, so-called inverted DNA , with internal positive charges and external nucleic bases. Cooperative effects lead preferentially to two identical strands in these helicates when copper(I) ions are added to a mixture of two different homooligomers. [Pg.345]

The goals of quality assessment are to determine when a system has reached a state of statistical control to detect when the system has moved out of statistical control and, if possible, to suggest why a loss of statistical control has occurred so that corrective actions can be taken. For convenience, the methods of quality assessment are divided into two categories internal methods that are coordinated within the laboratory and external methods for which an outside agency or individual is responsible. The incorporation of these methods into a quaKty assurance program is covered in Section 15C. [Pg.708]

Figure 2.7 shows a representation of this situation. The ordinate is an energy axis and the abscissa is called the reaction coordinate and represents the progress of the elementary step. In moving from P to H, the particle simply moves from one equilibrium position to another. In the absence of any external forces, the energy of both the initial and final locations should be the same as shown by the solid line in Fig. 2.7. Between the two minima corresponding to the initial and final positions is the energy barrier arising from the dislodging of the particles neighboring the reaction path from their positions of minimum energy. Figure 2.7 shows a representation of this situation. The ordinate is an energy axis and the abscissa is called the reaction coordinate and represents the progress of the elementary step. In moving from P to H, the particle simply moves from one equilibrium position to another. In the absence of any external forces, the energy of both the initial and final locations should be the same as shown by the solid line in Fig. 2.7. Between the two minima corresponding to the initial and final positions is the energy barrier arising from the dislodging of the particles neighboring the reaction path from their positions of minimum energy.
T[[dotb]he nature of the initial attack by the water (eq. 10) is a matter of some controversy (205,206). Stereochemical and kinetic studies of model systems have been reported that support trans addition of external water (207,208) or internal addition of cis-coordinated water (209), depending on the particular model system under study. Other paHadium-cataly2ed oxidations of olefins ia various oxygen donor solvents produce a variety of products including aldehydes (qv), ketones (qv), vinyl acetate, acetals, and vinyl ethers (204). However the product mixtures are complex and very sensitive to conditions. [Pg.183]

The coordinates of thermodynamics do not include time, ie, thermodynamics does not predict rates at which processes take place. It is concerned with equihbrium states and with the effects of temperature, pressure, and composition changes on such states. For example, the equiUbrium yield of a chemical reaction can be calculated for given T and P, but not the time required to approach the equihbrium state. It is however tme that the rate at which a system approaches equihbrium depends directly on its displacement from equihbrium. One can therefore imagine a limiting kind of process that occurs at an infinitesimal rate by virtue of never being displaced more than differentially from its equihbrium state. Such a process may be reversed in direction at any time by an infinitesimal change in external conditions, and is therefore said to be reversible. A system undergoing a reversible process traverses equihbrium states characterized by the thermodynamic coordinates. [Pg.481]


See other pages where External coordinate is mentioned: [Pg.40]    [Pg.325]    [Pg.34]    [Pg.797]    [Pg.146]    [Pg.30]    [Pg.127]    [Pg.797]    [Pg.29]    [Pg.156]    [Pg.288]    [Pg.445]    [Pg.84]    [Pg.40]    [Pg.325]    [Pg.34]    [Pg.797]    [Pg.146]    [Pg.30]    [Pg.127]    [Pg.797]    [Pg.29]    [Pg.156]    [Pg.288]    [Pg.445]    [Pg.84]    [Pg.16]    [Pg.478]    [Pg.519]    [Pg.1057]    [Pg.1059]    [Pg.1075]    [Pg.1573]    [Pg.553]    [Pg.676]    [Pg.41]    [Pg.55]    [Pg.158]    [Pg.314]    [Pg.403]    [Pg.585]    [Pg.35]    [Pg.10]    [Pg.128]    [Pg.72]   
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Coordinates, atomic external

External attack of nucleophiles on alkene coordinated to electrophilic metal complexes

External attack on coordinated substrates

External coordinates continuous

External coordinates discrete

External coordinates domain

External or Internal Coordinates

External symmetry coordinates

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