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DIMENSION Subject

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 elongation of film strips of fixed dimensions subjected to a constant load of 0.17 kg./sq.mm. is measured as a function of temperature. Heating rate is standardized at 10°C. per minute. The temperature range where an appreciable rise in elongation of the films is observed is taken as the softening point (S.P.)... [Pg.191]

A thermodynamic system is a part of the physical universe with a specified boundary for observation. A system contains a substance with a large amount of molecules or atoms, and is formed by a geometrical volume of macroscopic dimensions subjected to controlled experimental conditions. An ideal thermodynamic system is a model system with simplifications to represent a real system that can be described by the theoretical thermodynamics approach. A simple system is a single state system with no internal boundaries, and is not subject to external force fields or inertial forces. A composite system, however, has at least two simple systems separated by a barrier restrictive to one form of energy or matter. The boundary of the volume separates the system from its surroundings. A system may be taken through a complete cycle of states, in which its final state is the same as its original state. [Pg.1]

Figure 7 The velocity (top) and volume (bottom) distribution functions for a simple particle in three dimensions subject to the potential of Eqs. [90]. The solid line in the velocity distribution function plot is the result obtained from Eqs. [76] the dashed line is the analytical result. Figure 7 The velocity (top) and volume (bottom) distribution functions for a simple particle in three dimensions subject to the potential of Eqs. [90]. The solid line in the velocity distribution function plot is the result obtained from Eqs. [76] the dashed line is the analytical result.
From the classical literature on continuum theories of diffusion-reaction processes based on Eq. (4.1), it is anticipated that the larger the system size, the longer the time scale required for the reactive event, Eq. (4.2), to occur. The corresponding dependence for lattice systems was first proved analytically by Montroll and Weiss [17-19] who studied nearest-neighbor random walks on finite lattices of integral dimension subject to periodic boundary conditions. In a lattice-based approach to diffusion-controlled processes, one can also examine the influence of the number of pathways (or reaction channels) available to the diffusing coreactant at each point in the... [Pg.396]

We now argue that, for finite t, rejecting moves is the choice with the smaller time-step error when the importance-sampled Green function is employed. Sufficiently close to a node, the component of the velocity perpendicular to the node dominates all other terms in the Green function and it is illuminating to consider a free particle in one dimension subject to the boundary condition that have a node at x = 0. The exact Green function for this problem is... [Pg.103]

Reflectivity can also be described as the motion of the neutron in one dimension subjected to a pseudopotential whose magnitude is related to the scattering-length density of the medium. Using the Schrodinger equation to describe the perpendicular component of the motion eventually results in the... [Pg.248]

The results based on the experimentation are usually of two types studies of the materials on the variation of the thermal and mechanical properties depending on the temperature (characterization tests) or analysis of masonry structural elements of large dimensions subjected to high temperatures (verification tests). [Pg.440]

This equation of motion of a particle moving in one dimension subject to a potential V can be generalized to three dimensions ... [Pg.61]

The dynamic picture of a vapor at a pressure near is then somewhat as follows. If P is less than P , then AG for a cluster increases steadily with size, and although in principle all sizes would exist, all but the smallest would be very rare, and their numbers would be subject to random fluctuations. Similarly, there will be fluctuations in the number of embryonic nuclei of size less than rc, in the case of P greater than P . Once a nucleus reaches the critical dimension, however, a favorable fluctuation will cause it to grow indefinitely. The experimental maximum supersaturation pressure is such that a large traffic of nuclei moving past the critical size develops with the result that a fog of liquid droplets is produced. [Pg.330]

From now on, the index M will be omitted and it will be understood that any subject to be treated will refer to a finite sub-Hilbert space of dimension M. [Pg.645]

Now, in principle, the angle of contact between a liquid and a solid surface can have a value anywhere between 0° and 180°, the actual value depending on the particular system. In practice 6 is very difficult to determine with accuracy even for a macroscopic system such as a liquid droplet resting on a plate, and for a liquid present in a pore having dimensions in the mesopore range is virtually impossible of direct measurement. In applications of the Kelvin equation, therefore, it is almost invariably assumed, mainly on grounds of simplicity, that 0 = 0 (cos 6 = 1). In view of the arbitrary nature of this assumption it is not surprising that the subject has attracted attention from theoreticians. [Pg.123]

Water drops condensed in the atmosphere have much larger dimensions than gas molecules hence they are subject to the interference phenomena mentioned at the end of the last section. This alters the color of the scattered light. Smoke and dust particles are also larger and may absorb as well. [Pg.677]

A more important effect of prestressiag is its effect on the mean stress at the bore of the cylinder when an internal pressure is appHed. It may be seen from Figure 6 that when an initially stress-free cylinder is subjected to an internal pressure, the shear stress at the bore of the cylinder increases from O to A. On the other hand, when a prestressed cylinder of the same dimensions is subjected to the same internal pressure, the shear stress at the bore changes from C to E. Although the range of shear stress is the same ia the two cases (distance OA = CE), the mean shear stress ia the prestressed cylinder, represented by point G, is smaller than that for the initially stress-free cylinder represented by point H. This reduction in the mean shear stress increases the fatigue strength of components subjected to repeated internal pressure. [Pg.81]

X-ray diffraction work (11,15) shows that there is an ionomer peak at 4°C which is absent in the acid precursor. This low, broad peak is not affected by annealing or ion type and persists up to 300°C. Since the 4°C peak corresponds to a spacing of about 2.5 nm, it is reasonable to propose a stmctural feature of this dimension in the ionomer. The concept of ionic clusters was initially suggested to explain the large effects on properties of relatively sparse ionic species (1). The exact size of the clusters has been the subject of much debate and has been discussed in a substantial body of Hterature (3,4,18—20). A theoretical treatment has shown that various models can give rise to supramoleculat stmctures containing ionic multiplets which ate about 10 nm in diameter (19). [Pg.407]

Standards have been a part of technology since building began, both at a scale that exceeded the capabiUties of an individual, and for a market other than the immediate family. Standardization minimizes disadvantageous diversity, assures acceptabiUty of products, and faciUtates technical communication. There are many attributes of materials that are subject to standardization, eg, composition, physical properties, dimensions, finish, and processing. Implicit to the realization of standards is the availabiUty of test methods and appropriate caUbration techniques. Apart from physical or artifactual standards, written or paper standards also must be considered, ie, their generation, promulgation, and interrelationships. [Pg.17]

Smooth surfaces are normally estabflshed by calendering, a process which subjects the fabric at the nip point(s) of two or more roUs to the influence of controlled time, temperature, and pressure. When calendering is used as a thermal-bonding process, the roUs are of the same dimension and composition and are independently driven. However, when calendering is used as a fabric finishing operation, the roUs are frequently of different dimensions and composition and are not always independently driven. [Pg.156]

To eliminate the ambiguities in the subject of electricity and magnetism, it is convenient to add charge q to the traditional I, m and t dimensions of mechanics to form the reference dimensions. In many situations permittivity S or permeabiUty ]1 is used in Heu of charge. For thermal problems temperature Tis considered as a reference dimension. Tables 2 and 3 Hst the exponents of dimensions of some common variables in the fields of electromagnetism and heat. [Pg.104]


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