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Profile contributions

Since the driving force of the flow is uniformly distributed across the diameter of the capillary, the flow profile is essentially flat. This flat profile contributes to the very high separation efficiency of CZE. Electroosmotic pumping therefore is beneficial, in contrast to laminar flow generated by a HPLC pump, where a parabolic flow profile is established. The electroosmotic flow rate and its flat profile are generally independent of the capillary diameter. However, if the internal diameter of the capillary exceeds 250 pun, the flat profile is increasingly disrupted. [Pg.23]

When pressure broadening dominates, the situation is more complicated because the resulting Lorentzian profile contributes significant area far from the line center. A further complication in this case is that the Lorentzian half-width cannot be accurately calculated and must be measured in other experiments. If both Doppler and pressure broadening are present, however, and if the Lorentzian to Doppler half-width ratio is small, the correction necessitated by pressure broadening is small. In this situation an accurate value of the Lorentzian half-width may not be needed. Line strength in the case of combined Doppler and pressure broadening may be obtained from the equivalent width by the use of tables (Jansson and Korb, 1968). [Pg.58]

Alternating Least Square Optimization. The optimization process starts the iterative calculations from the initial estimates (spectral or electrophoretic profiles) of species to be modeled. If spectra are used as an input, the conjugated peak profile contributions C can be calculated as follows ... [Pg.210]

It is clear from Fig. 8 how important it is that the threshold of oscillation be reached very fast to enable the stimulated processes to compete with the collisional deactivation processes. It has been assumed so far that the full inversion under the entire spontaneous-emission line profile contributes to... [Pg.20]

Metabolic Profiling, ed. G.G. Harrigan and R. Goodacre, Kluwer Academic Publishers, Norwell, Mass., 2003 R 212 J.L. Griffin and E. Sang, Can NMR Derive Metabolic Profiles Contribute to Proteomic Analyses A Study on Duchenne Muscular Dystrophy , p. 39... [Pg.44]

Fig. 7.40 Different contributions to the Fe (110) line profile during an isothermal treatment (at 650 K). Data were taken each 15 h in He (50ml/min). Meeisurements were done under the addition of Ar or nitrogen (grey blocks). Contribution 1 denotes the m un intensity at 240 pm with the narrow linewidth, contribution 2 the peak at 240 pm with the wide profile, contribution 3 the peak at 243 pm. In the lower panel the ratio of the 240 to 243 pm intensities and the relative contribution of the total (110) intensity are compared with each other and the gas phase composition ... Fig. 7.40 Different contributions to the Fe (110) line profile during an isothermal treatment (at 650 K). Data were taken each 15 h in He (50ml/min). Meeisurements were done under the addition of Ar or nitrogen (grey blocks). Contribution 1 denotes the m un intensity at 240 pm with the narrow linewidth, contribution 2 the peak at 240 pm with the wide profile, contribution 3 the peak at 243 pm. In the lower panel the ratio of the 240 to 243 pm intensities and the relative contribution of the total (110) intensity are compared with each other and the gas phase composition ...
The reader is referred to Chapter 15 of the book by J.P. Couderc, C. Gourdon, and A. Line (Phenomenes de transfert en gMe des precedes, Lavoisier, 2008) and in particular to its section 6, which explains how the non-uniformity of velocity profiles contributes to the dispersion of a tracer. This effect is less significant in turbulent flow than it is in laminar flow, as turbulence tends to render the velocity profile uniform (see Exercise 8.1 of Chapter 8). [Pg.178]

Fig. XI-6. Polymer segment volume fraction profiles for N = 10, = 0-5, and Xi = 1, on a semilogarithinic plot against distance from the surface scaled on the polymer radius of gyration showing contributions from loops and tails. The inset shows the overall profile on a linear scale, from Ref. 65. Fig. XI-6. Polymer segment volume fraction profiles for N = 10, = 0-5, and Xi = 1, on a semilogarithinic plot against distance from the surface scaled on the polymer radius of gyration showing contributions from loops and tails. The inset shows the overall profile on a linear scale, from Ref. 65.
Figure A2.4.8. Potential energy profile at the metal-vacuum interface. Bulk and surface contributions to Vare shown separately. From [16]. Figure A2.4.8. Potential energy profile at the metal-vacuum interface. Bulk and surface contributions to Vare shown separately. From [16].
Equilibration of the interface, and the establislnnent of equilibrium between the two phases, may be very slow. Holcomb et al [183] found that the density profile p(z) equilibrated much more quickly than tire profiles of nonnal and transverse pressure, f yy(z) and f jfz), respectively. The surface tension is proportional to the z-integral of Pj z)-Pj z). The bulk liquid in the slab may continue to contribute to this integral, indicatmg lack of equilibrium, for very long times if the initial liquid density is chosen a little too high or too low. A recent example of this kind of study, is the MD simulation of the liquid-vapour surface of water at temperatures between 316 and 573 K by Alejandre et al [184]. [Pg.2271]

This fomi is called a Ginzburg-Landau expansion. The first temi f(m) corresponds to the free energy of a homogeneous (bulk-like) system and detemiines the phase behaviour. For t> 0 the fiinction/exliibits two minima at = 37. This value corresponds to the composition difference of the two coexisting phases. The second contribution specifies the cost of an inhomogeneous order parameter profile. / sets the typical length scale. [Pg.2370]

Computer Models, The actual residence time for waste destmction can be quite different from the superficial value calculated by dividing the chamber volume by the volumetric flow rate. The large activation energies for chemical reaction, and the sensitivity of reaction rates to oxidant concentration, mean that the presence of cold spots or oxidant deficient zones render such subvolumes ineffective. Poor flow patterns, ie, dead zones and bypassing, can also contribute to loss of effective volume. The tools of computational fluid dynamics (qv) are useful in assessing the extent to which the actual profiles of velocity, temperature, and oxidant concentration deviate from the ideal (40). [Pg.57]

Vinyl acetate is a colorless, flammable Hquid having an initially pleasant odor which quickly becomes sharp and irritating. Table 1 Hsts the physical properties of the monomer. Information on properties, safety, and handling of vinyl acetate has been pubUshed (5—9). The vapor pressure, heat of vaporization, vapor heat capacity, Hquid heat capacity, Hquid density, vapor viscosity, Hquid viscosity, surface tension, vapor thermal conductivity, and Hquid thermal conductivity profile over temperature ranges have also been pubHshed (10). Table 2 (11) Hsts the solubiHty information for vinyl acetate. Unlike monomers such as styrene, vinyl acetate has a significant level of solubiHty in water which contributes to unique polymerization behavior. Vinyl acetate forms azeotropic mixtures (Table 3) (12). [Pg.458]

Yeast (qv) metabolize maltose and glucose sugars via the Embden-Meyerhof pathway to pymvate, and via acetaldehyde to ethanol. AH distiUers yeast strains can be expected to produce 6% (v/v) ethanol from a mash containing 11% (w/v) starch. Ethanol concentration up to 18% can be tolerated by some yeasts. Secondary products (congeners) arise during fermentation and are retained in the distiUation of whiskey. These include aldehydes, esters, and higher alcohols (fusel oHs). NaturaHy occurring lactic acid bacteria may simultaneously ferment within the mash and contribute to the whiskey flavor profile. [Pg.84]

Reduction in semm Hpids can contribute significantly to prevention of atherosclerosis. In 1985 a consensus report indicating that for every 1% reduction in semm cholesterol there is a 2% reduction in adverse effects of coronary heart disease was issued (145). Recommended semm cholesterol concentration was 200 mg/dL for individuals under 30 years of age, and individuals having concentration 240 mg/dL and LDL-cholesterol over 160 mg/dL should undertake dietary modification and possibly pharmacotherapy (146). Whereas the initial step in reducing semm cholesterol is through reduction of dietary cholesterol intake, a number of dmgs are available that can affect semm Hpid profile (see Fat substitutes). The pathway to cholesterol synthesis is shown in Figure 2. [Pg.130]

FIG. 20-80 Heckel profiles of the unloaded relative compact density for (1) a material densifying by pure plastic deformation, and (2) a material densifying with contributions from brittle fragmentation and particle rearrangement. [Pg.1891]

While the F-N curve is a cumulative illustration, the risk profile shows the expected frequency of accidents of a particular category or level of consequence. The diagonal line is a line of constant risk defined such that the product of expected frequency and consequence is a constant at each point along the line. " As the consequences of accidents go up, the expected frequency should go down in order for the risk to remain constant. As the example illustrates, if a portion of the histogram sticks its head up above the line (i.e., a particular type of accident contributes more than its fair share of the risk), then that risk is inconsistent with the risk presented by other accident types. (Note There is no requirement that you use a line of constant risk other more appropriate risk criteria for your application can be easily defined and displayed on the graph.)... [Pg.43]

Recent experiments by Gray et al. [47] have probed the contribution of the Bauschinger effect on real-time unloading wave profiles and postshock... [Pg.207]

Figure 6.17. VISAR wave profiles of copper and silicon bronze at 10 GPa exhibiting differing unloading wave shapes supporting a Bauschinger effect contribution to unloading. Figure 6.17. VISAR wave profiles of copper and silicon bronze at 10 GPa exhibiting differing unloading wave shapes supporting a Bauschinger effect contribution to unloading.
A procedure commonly used to extract dynamic data directly from experimental incoherent neutron scattering profiles is described in Ref. 17. It is assumed that the atomic position vectors can be decomposed into two contributions, one due to diffusive motion, fi /t), and the other from vibrations, Uijt), i.e.. [Pg.246]


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See also in sourсe #XX -- [ Pg.277 ]




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