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Conservation relations

Conservation relations are used to derive mechanical stress-volume states from observed wave profiles. Once these states have been characterized through experiment or theory they may, in turn, predict wave profiles for the material in question. For the case of a well-defined shock front propagating at constant speed L/ to a constant pressure P and particle velocity level u, into a medium at rest at atmospheric pressure, with initial density, p, the conservation of momentum, mass, and energy leads to the following relations ... [Pg.18]

Within the elastic regime, the conservation relations for shock profiles can be directly applied to the loading pulse, and for most solids, positive curvature to the stress volume will lead to the increase in shock speed required to propagate a shock. The resulting stress-volume relations determined for elastic solids can be used to determine higher-order elastic constants. The division between the elastic and elastic-plastic regimes is ideally marked by the Hugoniot elastic limit of the solid. [Pg.20]

The materials responses for which the shock-conservation relations of Eqs. (2.1) are representative are limited. For a more general structured wave pro-... [Pg.20]

Table 3.3 summarizes the history of the development of wave-profile measurement devices as they have developed since the early period. The devices are categorized in terms of the kinetic or kinematic parameter actually measured. From the table it should be noted that the earliest devices provided measurements of displacement versus time in either a discrete or continuous mode. The data from such measurements require differentiation to relate them to shock-conservation relations, and, unless constant pressures or particle velocities are involved, considerable accuracy can be lost in data processing. [Pg.62]

Tube Side Condensation Pressure Drop Kem recommends the following conservative relation ... [Pg.211]

That the rates of reactant consumption and product growth are equal in the steady state is a consequence of setting d[Vjdt = 0. We can see this from the mass conservation relation,... [Pg.78]

The Xm values can be found in [151] or in [145]. These tabulated values and the two following volume conservation relations allow a complete determination of the characteristic lengths of the instability ... [Pg.23]

Assume, as in Fig 2, a piston starting from rest at X=0 and immediately accelerated to a velocity uj. Later at time t, the piston is at some position X-. Conservation relations may be written for the gas contained betw the piston and some moving boundary at position x and traveling at a velocity u-, where subscript t denotes transmitted conditions. The relations are ... [Pg.524]

Analysis of photofragment velocities (speed and angle) has become the mainstay of modern photodissociation studies [14,15], Simple energy and momentum conservation relations are the basis of these studies. [Pg.62]

In the context of conservation relations another form will be added. If equ. (10.39b) is squared, one can introduce an area A to replace y2, a solid angle 2 to replace a2 and a so-called brightness B which is proportional to (see below). This gives... [Pg.389]

Where coni is the component represented by equation 5.3-6. Row reduction yields equation 5.3-5, which shows that the stoichiometric number matrix and conservation matrix are equivalent. The last column of equation 5.3-5 shows that there is a single reaction and that it agrees with equation 5.3-3. When coupling introduces additional conservation equations, components can be chosen in such a way that the conservation relations are all expressed in terms of conservations of reactants that are chosen as components. Thus equation 5.3-5 utilizes the five components glutamate, ATP, ammonia, ADP, and P . [Pg.98]

Glycolysis involves 10 biochemical reactions and 16 reactants. Water is not counted as a reactant in writing the stoichiometric number matrix or the conservation matrix for reasons described in Section 6.3. Thus there are six components because C = N — R = 16 — 10 = 6. From a chemical standpoint this is a surprise because the reactants involve only C, H, O, N, and P. Since H and O are not conserved at specified pH in dilute aqueous solution, there are only three conservation equations based on elements. Thus three additional conservation relations arise from the mechanisms of the enzyme-catalyzed reactions in glycolysis. Some of these conservation relations are discussed in Alberty (1992a). At specified pH in dilute aqueous solutions the reactions in glycolysis are... [Pg.114]

This shows that the natural variables for G for this system before phase equilibrium is established are T, P, nAx, and nAp. When A is transferred from one phase to the other, dnAa = — dnAp. Substituting this conservation relation into equation 8.1-1 yields... [Pg.142]

Thus the row reduced form represents the conservation relations equally well. [Pg.318]

A ny discussion of a national preservation program for library materials must review the documents, concepts, and events that mold our present thinking. Such a program is nebulous in the broad sense, but specific in its component parts. This is attributable partly to the relatively short time the idea of a national preservation program has been a subject of serious discussion and partly to the varied constituencies involved and interested in the preservation of such materials. Librarians, scientists, and conservators relate to such a program in different ways and tend to consider most important those facets of the program most germane to their interests and skills. [Pg.9]

Construct a computer program to reproduce the simulation outlined in Section 6.1.4. Compare the behavior of the conservation relations (H0, M0, and Ka) computed using different solvers and numerical settings. [Pg.161]

We find the rate of change of the internal energy for an observer at rest by subtracting Eq. (3.109) from the total energy conservation relation Eq. (3.99) and using Eq. (3.102)... [Pg.118]

The flow or concentration control coefficients are related to elasticity coefficients through the conservation relations and connectivity theorems. [Pg.558]

Suppose now that Eq. (5-112) is integrated over the entire confining surface of an enclosure which has been subdivided into M finite area elements. Each of the M surface zones must then satisfy certain conservation relations involving all the direct exchange areas in the enclosure... [Pg.22]

Finally the four matrix arrays ss, gs, SS, and SG of direct and total exchange areas must satisfy matrix conservation relations, i.e.,... [Pg.25]

LVi X Qi = 0, which is a statement of the overall radiant energy i= 1 The matrix conservation relations also simplify to balance. [Pg.26]

The matrices gg = [g g, and GG = [G,Gf] must also satisfy the following matrix conservation relations ... [Pg.35]

Clearly when K = 0, the two direct exchange areas involving a gas zone g[ j and g gj vanish. Computationally it is never necessary to make resort to Eq. (5-155) for calculation of gg,. This is so because sj, gSj, and gg may all be calculated arithmetically from appropriate values of StSj by using associated conservation relations and view factor algebra. [Pg.35]

Extension toward the fully nonlinear case is straightforward for 1-DOF Hamiltonians. The energy conservation relation H p,q) = E allows us to dehne (explicitly or implicitly) p = p q E), thereby reducing the ODE to a simple quadrature. In this procedure there is no problem of principle (unlike the n >2-DOE case). It works in practice also, and it is possible to adapt Eigs. 3-5 to the nonlinear regime. It must be underlined that besides that simple procedure, we present a theorem in dynamical system theory (containing Hamiltonian dynamics as a particular case). This theorem is valid for n DOEs (hence for n = 1) it relates the full dynamics to the linearized dynamics, called tangent dynamics in the mathematical literature. [Pg.227]

As shown for the 2D case with infinite nucleus mass in Section 111, in this subsection we shall construct the TCM for the collinear eZe case with finite masses and shall elucidate the behavior near triple collisions. We use the McGehee s original transformation [22]. The derivation of the TCM is successive application of tricky transformations to the equations of motion and the energy conservation relation. We do not show all of the derivation. The readers are strongly recommended to consult with Refs. 22 and 29 for details. [Pg.320]

Imielinski, M., Belta, C., Rubin, H. and Halasz, A. (2006) Systematic analysis of conservation relations in Escherichia coH genome-scale metabolic network reveals novel growth media. Biophys. J. 90, 2659-2672. [Pg.258]

All of the open problems for the standard gradostat system of Chapter 6 are open problems for the unstirred chemostat model discussed in Chapter 10. It can be shown [HSW] that the dynamics of the unstirred chemostat system mirror those of the gradostat in the sense that there is an order interval, bounded by two (possibly identical) positive rest points, that attracts all solutions. Furthermore, an open and dense set of initial data generates solutions that converge to a stable rest point. The question of the uniqueness of the interior rest point is a major open problem. Another is how to handle the case where the diffusion coefficients of the competitors and nutrient are distinct. Although there must still be conservation of total nutrient, it is no longer a pointwise conservation relation and the reduction to two equations is not clear. Even if accomplished, it may be difficult to exploit. If one is forced to analyze the full... [Pg.251]

The nondiagonal terms refer to the fraction of erroneous copying processes for which the conservation relation must hold... [Pg.158]

The conservation relation (II. 1) allows for a simplification of the summed rate terms, in terms of the total excess production rates E, such that the quality factors Qii no longer appear as average excess production E(t) we define... [Pg.159]

Let us now compare the mathematical structures of the selection Eqn. (III. 15) and the coupled systems of Eq. (III. 16) and (III. 17) The original equation had rs variables and one conservation relation and was linear apart from the mild nonlinearity caused by E. Equations (III. 16) and (III. 17) contain r + s variables only they fulfil two conservation relations but are highly nonlinear through the coupling terms. We recall from Appendix 9 that, For example,... [Pg.189]


See other pages where Conservation relations is mentioned: [Pg.21]    [Pg.317]    [Pg.386]    [Pg.90]    [Pg.337]    [Pg.476]    [Pg.316]    [Pg.173]    [Pg.29]    [Pg.144]    [Pg.55]    [Pg.24]    [Pg.26]    [Pg.27]    [Pg.37]    [Pg.37]    [Pg.11]   
See also in sourсe #XX -- [ Pg.18 , Pg.36 ]




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