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Order essential

Solve the convection equation of high order (3rd order) essentially non-oscillatory (ENO) upwind scheme (Sussman et al., 1994) is used to calculate the convective term V V

velocity field P". The time advancement is accomplished using the second-order total variation diminishing (TVD) Runge-Kutta method (Chen and Fan, 2004). [Pg.30]

The acidifying effect of the remaining acceptor substituents of Table 13.1 decreases in the order —C(=0)—H > —C(=0)—alkyl > -C(=0)—O-alkyl, and the amide group —C (=0)-NR2 is even less effective. This ordering essentially reflects substituent effects on the... [Pg.523]

The acidifying effect of the remaining acceptor substituents of Table 10.1 decreases in the order —C(=0)—H > —C(=0)—alkyl > —C(=0)—O-alkyl, and the amide group —C(=0)—NR2 is even less effective. This ordering essentially reflects substituent effects on the stability of the C=0 double bond in the respective C,H-acidic compound. The resonance stabilization of these C=0 double bonds drastically increases in the order R—C(=0)—H < R—C(=0)—alkyl < R—C(=0)—0—alkyl < R—C(=0)— NR2 (cf. Table 6.1 see Section 7.2.1 for a comparison between the C=0 double bonds in aldehydes and ketones).This resonance stabilization is lost completely once the a-H-atom has been removed by way of deprotonation and the respective enolate has formed. [Pg.377]

It may have occurred to the reader that certain grid sections of upper Manhattan and Chicago are, despite their formal order, essentially ungoverned and... [Pg.369]

Partial orders of reaction are of more interest than the overall order. Essentially, the overall order of reaction provides a convenient means of categorizing reactions, but otherwise is of little importance. [Pg.40]

One useful technique is an extension of the method of analyzing the behavior of a system in the neighborhood of a steady state by linearizing the equations in that neighborhood. If one keeps the lowest order essential nonlinear terms as well, then one obtains the so-called normal form, which displays not only the stability of the steady state, but also how the properties of that state change as the control parameter passes through the bifurcation point. [Pg.42]

The term of first order essentially only yields forces of short range. If the total angular momentum vanishes, behaves asymptotically as If the... [Pg.405]

Something additional will be needed to calculate heats of formation for compounds that contain delocalized electronic systems, particularly aromatic compounds, and related substances. Tlie problem with the methods previously described when applied to these systems is that one cannot expect to have constant bond energy or bond enthalpy units, because conjugated bonds come with various kinds of bond orders essentially from zero to one in the jr-bond component (or up to two if acetylenes are included), and these different bond orders correspond to different bond lengths and to different bond energies. Somehow this all has to be taken into account if one is to apply the calculation schemes described previously to these conjugated systems. [Pg.1223]

A. Harten, B. Engquist, S. Osher, and S. Ghakravarthy (1987) Uniformly high order essentially non-osciUatory schemes, Ui. J. Comput. Phys. 71, 231-303. [Pg.387]

The CP table. Identification of the essential matches in the region of the pinch is clarified by use of a CP table. In a CP table, the CP values of the hot and cold streams at the pinch are listed in descending order. [Pg.366]

The accuracy of the conversion depends on the smoothness of the D 86 curve. Errors affect essentially the points in the low % distilled ranges. Average error is on the order of 5°C for conversion of a smooth curve. [Pg.100]

The preceding information indicates the paths to follow in order to obtain stocks of high octane number by refining. The orientation must be towards streams rich in aromatics (reformate) and in isoparaffins (isomerization, alkylation). The olefins present essentially in cracked gasolines can be used only with moderation, considering their low MONs, even if their RONs are attractive. [Pg.202]

Utilization of LPG as motor fuel represents only a tiny fraction of the market, on the order of 30,000 t/an in France out of a total 3,000,000 t that is, about 1%. Globally, the fraction of LPG used in the transportation industry is on the order of 5% the other applications are essentially petrochemicals (25%) and the heating fuel sectors (70%). However noticeable openings in the LPG-fuel markets in some countries such as Japan (1.8 Mt), the United States (1.3 Mt), the Netherlands (0.9 Mt), Italy (0.8 Mt) and in certain regions (Latin America, Africa, and the Far East) have been observed for specialized vehicles such as taxis. [Pg.230]

As reported before [Ref. 1], there are some essential parameters that influence the results of the testing, such as the thickness of the expired specimen, the quality and coarse grain of the built-in concrete, and the properties of the specimen-surface for the transducer s coupling. At the onset of testings none of tlrese parameters were available. As a result, we had to carry out preliminary investigations in order to prove the applicability of our testing-technique "in situ". [Pg.754]

In the framework of the new approach third parties have a particular responsibility. Their task has become more difficult especially in cases where products are manufactured directly to the essential requirements. In that case competent interpretation and judgement needs to be applied in order to evaluate whether the required safety level is achieved or not. Not only safeguard clauses and their economic consequences should be avoided but also possible distortion of the market. An exchange of experience between bodies which are notified for a given directive is therefore normally organised with a view to ensuring its coherent application and to avoid such negative consequences. [Pg.939]

The preliminary observations underline the manufacturer s responsibilities. He is obliged to analyse the hazards in order to identify those which apply to his equipment. He must design, manufacture and check his equipment to ensure its safety even with respect to their use under reasonably foreseeable conditions. In addition, the manufacturer must interpret and apply the essential requirements in such a way as to take account of the state-of-the-art at the time of design. That latter requirement underlines the evolutive character of the essential requirements which is inherent in the new approach. [Pg.941]

The next point of interest has to do with the question of how deep the surface region or region of appreciably unbalanced forces is. This depends primarily on the range of intermolecular forces and, except where ions are involved, the principal force between molecules is of the so-called van der Waals type (see Section VI-1). This type of force decreases with about the seventh power of the intermolecular distance and, consequently, it is only the first shell or two of nearest neighbors whose interaction with a given molecule is of importance. In other words, a molecule experiences essentially symmetrical forces once it is a few molecular diameters away from the surface, and the thickness of the surface region is of this order of magnitude (see Ref. 23, for example). (Certain aspects of this conclusion need modification and are discussed in Sections X-6C and XVII-5.)... [Pg.56]

Here, if Z is expressed in moles of collisions per square centimeter per second, r is in moles per square centimeter. We assume the condensation coefficient to be unity, that is, that all molecules that hit the surface stick to it. At very low Q values, F as given by Eq. XVII-3 is of the order expected just on the basis that the gas phase continues uniformly up to the surface so that the net surface concentration (e.g., F2 in Eq. XI-24) is essentially zero. This is the situation... [Pg.602]

A third definition of surface mobility is essentially a rheological one it represents the extension to films of the criteria we use for bulk phases and, of course, it is the basis for distinguishing states of films on liquid substrates. Thus as discussed in Chapter IV, solid films should be ordered and should show elastic and yield point behavior liquid films should be coherent and show viscous flow gaseous films should be in rapid equilibrium with all parts of the surface. [Pg.711]

The principle of tire unattainability of absolute zero in no way limits one s ingenuity in trying to obtain lower and lower thennodynamic temperatures. The third law, in its statistical interpretation, essentially asserts that the ground quantum level of a system is ultimately non-degenerate, that some energy difference As must exist between states, so that at equilibrium at 0 K the system is certainly in that non-degenerate ground state with zero entropy. However, the As may be very small and temperatures of the order of As/Zr (where k is the Boltzmaim constant, the gas constant per molecule) may be obtainable. [Pg.373]

Ionic conductors arise whenever there are mobile ions present. In electrolyte solutions, such ions are nonually fonued by the dissolution of an ionic solid. Provided the dissolution leads to the complete separation of the ionic components to fonu essentially independent anions and cations, the electrolyte is tenued strong. By contrast, weak electrolytes, such as organic carboxylic acids, are present mainly in the undissociated fonu in solution, with the total ionic concentration orders of magnitude lower than the fonual concentration of the solute. Ionic conductivity will be treated in some detail below, but we initially concentrate on the equilibrium stmcture of liquids and ionic solutions. [Pg.559]


See other pages where Order essential is mentioned: [Pg.31]    [Pg.113]    [Pg.65]    [Pg.129]    [Pg.528]    [Pg.33]    [Pg.302]    [Pg.157]    [Pg.157]    [Pg.32]    [Pg.230]    [Pg.113]    [Pg.311]    [Pg.31]    [Pg.113]    [Pg.65]    [Pg.129]    [Pg.528]    [Pg.33]    [Pg.302]    [Pg.157]    [Pg.157]    [Pg.32]    [Pg.230]    [Pg.113]    [Pg.311]    [Pg.117]    [Pg.129]    [Pg.425]    [Pg.76]    [Pg.198]    [Pg.219]    [Pg.277]    [Pg.37]    [Pg.105]    [Pg.173]    [Pg.178]    [Pg.989]    [Pg.198]    [Pg.369]    [Pg.51]    [Pg.66]    [Pg.386]   
See also in sourсe #XX -- [ Pg.198 , Pg.200 , Pg.203 ]




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