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Dimensional expansions

For three-dimensional expansion in the air-filled section with the initial air volume equal to at least 200 times that of the initial water volume and with no partitions, baffles, or other types of compartments present, the air shock pressure is smaller than the final quasi-steady equilibrium pressure buildup. It can therefore be rationalized that the design of containment for a reactor is governed by equilibrium pressure only. [Pg.260]

In a solvent the polymer coil tends to swell to some degree depending on the nature of the solvent. The dimensional expansion is measured by the intramolecular expansion factor,... [Pg.452]

Similar one can define the isobaric two-dimensional expansion coefficient (also called expansivity coejficient) as... [Pg.224]

The process described is related to the unique effects carbon dioxide and moisture have on coal. Carbon dioxide readily and extensively penetrates the coal structure O). In fact, this has led to the advocacy of employing carbon dioxide to measure the internal area of coals. It is likely the CO2 diffuses into the coal along the lines of mineral inclusion as has been seen for other gases ( ). This is important since the diffusion of reagents through solid coal may be the rate-limiting step in many reactions. This diffusion has also been shown to cause a dimensional expansion of the structure. [Pg.502]

The bonds of the polymer molecule have been considered thus far as volumeless lines in space. In contradistinction, the bonds of real polymer molecules occupy flnite volumes in space. The repulsion between segments that are far removed from one another along the contour of the chain but spatially contiguous will cause the polymer chain to expand beyond the unperturbed dimensions. The magnitude of this dimensional expansion is measured by the intramolecular expansion factor a... [Pg.74]

The import of the above observation is that for molecules (and more generally for any problem which possesses a length scale independent of that defined by the electronic motions themselves), it is only from the dimensional limits obtained by the uniform scaling that one can hope to obtain quantitative results by means of simple procedures such as dimensional expansions and interpolation. [Pg.243]

The partial sums 5 of Eq. (11) are not suitable approximants for summing dimensional expansions for atoms and molecules since they cannot model the dimensional singularities. More effective approximants can be developed by incorporating what is known in advance about the singffiarity structure of the energy function E(S) into the form of the approximants. [Pg.298]

In Section A, we will describe several methods that only take into account poles and are therefore only appropriate at low orders. The low-order terms of dimensional expansions are relatively easy to derive, so these methods are useful for a quick qualitative analysis. This level of approximation corresponds to a simple physical model Eq is the energy of the infinite-P Lewis configuration, E corresponds to the harmonic Langmuir oscillations, and E2 represents cubic and quartic anharmonicities [13]. [Pg.299]

Fade approximants were used in Section 3.B. as a tool for singularity analysis, but their primary function is as a summation method. Unfortunately, their convergence with dimensional expansions tends to be rather slow and uneven. They can be useful if the expansion is known to high order, but they are not appropriate as a low-order summation technique. However, their rate of convergence can be improved considerably if they are used in conjunction with the hybrid expansion, of Eq.(38). The Fade approximants of the E converge quite well even at low order. We will refer to this technique as hybrid Fade summation. [Pg.303]

We report calculations of dimensional expansions for the energies of the three excited S states of helium that correspond to one quantum in either of the three normal modes of the Langmuir vibrations. Very accurate energies are obtained for the 1 25 states, which arise from... [Pg.359]

If effective absorbance and photothermal conversion efficiency are independent on the fluence, absorbed energy should be proportional to the latter and the slopes can be discussed simply in terms of thermal expansion coefficient of polymer Aims. The coefficient of linear expansion of rubber and glass states, ttg and Of, below and above glass-rubber transition temperature (Tg) of PMMA is (2.5-2.7) X 10- K and (5.6-5.S) X W K , respectively 3S). We consider that the one-dimensional expansion is induced along the perpendicular direction to the film, since polymer film outside the area irradiated by the excimer laser is of course hard. Then, the volume expansion could be replaced by the linear one along the thickness, so that corresponds to the change in the slope below... [Pg.220]

The first complete calculation for the onset and the progress of spontaneous condensation was described by Oswatitsch for a one-dimensional expansion of a vapour with ideal gas properties [5]. By means of a computer such calculations can now be performed even for vapours at high density with a complex equation of state to describe the real gas behaviour. In addition to the equations for the conservation of mass, momentum and energy and to the equation of state, a further equation for the increase of the mole fraction of condensate... [Pg.120]

Peter et al. [18] emphasized the role of the effect of uncompensated ohmic drop, and analyzed the current transients within the framework of the two-dimensional electrocrystallization model, taking into account instantaneous and progressive nu-cleations. Three-dimensional expansion of growth centers was also considered. It was found that the reduction is only rapid as long as the film remains in its conducting state. (A more detailed analysis of this problem is provided in Sect. 6.6.) It was also suggested that the electroneutrality is maintained by fast proton transport at short times. [Pg.72]

For maximum efficiency, maximizing the magnetic field flux across the voice coil requires the smallest coil to pole piece gap dimension possible based on peak voice coil excursion and power dissipation. As a practical matter this gap must be increased somewhat to compensate for dimensional expansion as operating temperature increases. [Pg.295]

Other methods of creating physically bound systems include spin-coating block copolymers containing azobenzene repeat units in one of the blocks. The spin-coated layers are then annealed at elevated temperatures to provide sufficient chain mobility and drive subsequent microphase separation. This synthetic strategy allows devices to be fabricated, which exhibit truly one-dimensional expansion and contraction cycles. Moreover, following use, the films can be dissolved up and recast, if necessary, to produce brand new devices from the very same material. [Pg.2677]

Obviously any basis set method is heavily reliant on the choice of appropriate expansion functions. Conventional vibrational basis set have usually been constructed from products of one-dimensional expansions of orthogonal polynomials. In particular Hermite or associated Laguerre... [Pg.324]

The density or specific gravity change of the shale particle to three-dimensional diffusion will result in a three-dimensional expansion. The incremental change in each direction may be calculated independently using the unidirectional expression... [Pg.235]

The condition Eq. (6.174) actually poses a certain limitation on the existence of the diabatic representation. One of its outcome is the ine3dstence of perfect diabatic basis in the finite dimensional expansion. To see this, we denote the projection on the finite basis set explicitly by P = Yljen where represents the label set of the basis. The requirement for diabati-zation becomes... [Pg.262]

FIGURE 33 COSY correlations are indicated on the structure of ibuprofen as well as in the two-dimensional expansions taken from the fuil two-dimensional data matrix in the top ieft-hand corner of the figure. [Pg.143]

Thermal fatigue is normally induced at elevated temperatures by fluctuating thermal stresses mechanical stresses from an external somce need not be present. The origin of these thermal stresses is the restraint to the dimensional expansion and/or contraction that would normally occm in a structural member with variations in tempera-tme. The magnitude of a thermal stress developed by a temperatme change AT depends on the coefficient of thermal expansion and the modulus of elasticity E according to... [Pg.281]

Linear Thermal Expansivity. In general, when the temperature of a material body changes, its dimensions change also these dimensional changes may be different in different directions. Therefore, depending on the natvire of the material, it is possible to consider one-, two-, or three-dimensional expansivity in this article the discussion is confined mostly to linear thermal expansivity. [Pg.1153]


See other pages where Dimensional expansions is mentioned: [Pg.1001]    [Pg.453]    [Pg.26]    [Pg.121]    [Pg.428]    [Pg.378]    [Pg.261]    [Pg.824]    [Pg.1154]    [Pg.101]    [Pg.335]    [Pg.1157]    [Pg.681]    [Pg.214]    [Pg.1005]    [Pg.239]    [Pg.18]    [Pg.27]    [Pg.336]    [Pg.359]    [Pg.15]    [Pg.49]    [Pg.20]    [Pg.2480]    [Pg.4]    [Pg.228]    [Pg.99]    [Pg.110]   
See also in sourсe #XX -- [ Pg.359 ]




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