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Superimposing solutions

A superposition of time is also possible, because, mathematically, time is simply the fourth dimension. Thus, if two solutions at different times are each solutions to the governing hnear differential equation, they can be added together to get a superimposed solution that will meet the boundary conditions of the application. This is demonstrated in Example 2.5. [Pg.40]

Determination of Indicator Constants.—A simple method of evaluating the constant of an indicator is to make use of equation (22). Two solutions, containing the same amount of indicator, one in the completely acid form and the other in the alkaline form, are superimposed the net color is equivalent to that of the total amount of indicator with equal portions in the ionized and un-ionized forms. A scries of buffer solutions of known pll (see Chap. XI) arc then prepared and a quantity of indicator, twdcc that present in each of the two superimposed solutions, is added the colors are then compan d with that of the latter until a match is obtained. The matching buffer solution consequently contains equal amounts of ionized and un-ionized indicator and so its pH is equal to the required pfcin. [Pg.363]

Undoubtedly, use of p-polarized light and a 60° prism gives a very high surface sensitivity. This is reflected by the fact that the center of the superimposed solution... [Pg.144]

Figure 7.6 Protection factor plots of the antistreptavidin lgC2 (heavy-chain residues are shown here) produced by HX modeling, (a) One solution (b) 20 superimposed solutions (c) average of the 20 solutions (See insert for color representation of the figure.)... Figure 7.6 Protection factor plots of the antistreptavidin lgC2 (heavy-chain residues are shown here) produced by HX modeling, (a) One solution (b) 20 superimposed solutions (c) average of the 20 solutions (See insert for color representation of the figure.)...
A cubic lattice is superimposed onto the solute(s) and the surrounding solvent. Values of the electrostatic potential, charge density, dielectric constant and ionic strength are assigned to each grid point. The atomic charges do not usually coincide with a grid point and so the... [Pg.620]

The effect of nitrous acid on the nitration of mesitylene in acetic acid was also investigated. In solutions containing 5-7 mol 1 of nitric acid and < c. 0-014 mol of nitrous acid, the rate was independent of the concentration of the aromatic. As the concentration of nitrous acid was increased, the catalysed reaction intervened, and superimposed a first-order reaction on the zeroth-order one. The catalysed reaction could not be made sufficiently dominant to impose a truly first-order rate. Because the kinetic order was intermediate the importance of the catalysed reaction was gauged by following initial rates, and it was shown that in a solution containing 5-7 mol 1 of nitric acid and 0-5 mol 1 of nitrous acid, the catalysed reaction was initially twice as important as the general nitronium ion mechanism. [Pg.58]

From the data in Fig. 4.8b, estimate the shift factors required to displace the data at 0 = 0.5 (consider only this point) so that all runs superimpose on the experiment conducted at 128 C at 0 = 0.5. Either a ruler or proportional dividers can be used to measure displacements. Criticize or defend the following proposition Whether a buffered aqueous solution of H2O2 and 1. containing small amounts of S2O3 and starch, appears blue or colorless depends on both the time and the temperature. This standard general chemistry experiment could be used to demonstrate the equivalency of time and temperature. The pertinent reactions for the iodine clock are... [Pg.266]

In some cases, however, it is possible, by analysing the equations of motion, to determine the criteria by which one flow pattern becomes unstable in favor of another. The mathematical technique used most often is linearised stabiHty analysis, which starts from a known solution to the equations and then determines whether a small perturbation superimposed on this solution grows or decays as time passes. [Pg.98]

Gaussian plume models are easy to use and require relatively few input data. Multiple sources are treated by superimposing the calculated contributions of individual sources. It is possible to include the first-order chemical decay of pollutant species within the Gaussian plume framework. For chemically, meteorologically, or geographically complex situations, however, the Gaussian plume model fails to provide an acceptable solution. [Pg.381]

Commercially pure aluminium (1000 series) and the non-heat-treatable aluminium alloys (3000 and 5000 series) are usually work hardened. The work hardening superimposes on any solution hardening, to give considerable extra strength (Table 10.5). [Pg.110]

The diffraction patterns due to different isochiral clusters are superimposed and well separated in a polychiral MWCNT diffraction pattern, suggesting that interference between waves scattered by tubes with different chiral angles can be neglected. It is therefore meaningful to discuss only isochiral clusters of tubes. Such clusters are only compatible with a constant intercylinder spacing c/2 for pairs of Hamada indices satisfying the condition = L +M +LM - (nc/a). Approximate solutions are for instance (8, 1) and (5, 5) [16,17]. [Pg.23]

Acid catalysis is an important kinetic phenomenon, and its study often requires the use of concentrated acid solutions, in which the conventional pH scale is not applicable. In sueh solutions (e.g., sulfuric acid-water mixtures covering the full range of compositions) the acid component simultaneously functions both as an acid and as a solvent thus, a medium effect is superimposed on the acidity effect. In this section we briefly describe the acidity function approach to coping with this problem. (A comparable approach can be taken to the study of highly... [Pg.446]

The ability of a GC column to theoretically separate a multitude of components is normally defined by the capacity of the column. Component boiling point will be an initial property that determines relative component retention. Superimposed on this primary consideration is then the phase selectivity, which allows solutes of similar boiling point or volatility to be differentiated. In GC X GC, capacity is now defined in terms of the separation space available (11). As shown below, this space is an area determined by (a) the time of the modulation period (defined further below), which corresponds to an elution property on the second column, and (b) the elution time on the first column. In the normal experiment, the fast elution on the second column is conducted almost instantaneously, so will be essentially carried out under isothermal conditions, although the oven is temperature programmed. Thus, compounds will have an approximately constant peak width in the first dimension, but their widths in the second dimension will depend on how long they take to elute on the second column (isothermal conditions mean that later-eluting peaks on 2D are broader). In addition, peaks will have a variance (distribution) in each dimension depending on... [Pg.81]

Fig. 1.19 Potential-pH diagram for copper in solutions containing and (NH4>2S04 (after Mattson ) with superimposed times to fracture Tf of direct-loaded a-brass wires held at various potentials in the solution of pH 7-2 the specimen without external polarisation had Ff = 3y h (after Hoar and Booker S)... Fig. 1.19 Potential-pH diagram for copper in solutions containing and (NH4>2S04 (after Mattson ) with superimposed times to fracture Tf of direct-loaded a-brass wires held at various potentials in the solution of pH 7-2 the specimen without external polarisation had Ff = 3y h (after Hoar and Booker S)...
The rate of corrosion of platinum anodes in chloride solutions increases if a considerable a.c. component is superimposed on the d.c. supply . [Pg.939]

The balance condition between the evaporator and the compressor can be visualized in a graphic solution, superimposing the basic rating of the cooler on the compressor curves (see Figure 10.1). [Pg.124]

The Orientation of Water Molecules Adjacent to an Ion. Order and Disorder in the Vicinity of Solute Particles. Coulomb Attraction and Repulsion between Ions. Activity Coefficients. The Distance of Closest Approach. Activity Coefficients of Various Solutes. Forces Superimposed on the Coulomb Forces. [Pg.248]

In low ionic strength solutions (I < 0.005 panel A), the curves obtained with the pH buffers MOPS and glycylglycine and also with a weak Ca2+-chelator citric acid are nearly superimposable on each other, whereas those obtained with the buffers that contain strong chelators EDTA and NTA are shifted almost 2 pCa units to the right. The curve for NTA is somewhat atypical probably the Ca2+-NTA ratio of the Ca2+-NTA complex used was not exactly 1.0. In the... [Pg.109]

In a number of works (e.g. [339-341]) the authors sought to superimpose graphically the flow curves of filled melts and polymer solutions with different filler concentrations however, it was only possible to do so at high shear stresses (rates). More often than not it was impossible to obtain a generalized viscosity characteristic at low shear rates, the obvious reason being the structurization of the system. [Pg.54]

There are ways of coping with these interferences. Pulse-height selection (2.13) is a direct method. As we shall see in Chapter 7, a particularly bad case, the determination of tungsten in aqueous solution with scattered target line and the identical line from the sample superimposed, could be handled successfully by properly correcting the background. [Pg.103]


See other pages where Superimposing solutions is mentioned: [Pg.201]    [Pg.244]    [Pg.1740]    [Pg.68]    [Pg.92]    [Pg.96]    [Pg.326]    [Pg.379]    [Pg.306]    [Pg.384]    [Pg.484]    [Pg.145]    [Pg.1117]    [Pg.71]    [Pg.476]    [Pg.970]    [Pg.207]    [Pg.1169]    [Pg.1310]    [Pg.40]    [Pg.61]    [Pg.155]    [Pg.192]    [Pg.251]    [Pg.236]    [Pg.207]    [Pg.215]    [Pg.87]   
See also in sourсe #XX -- [ Pg.107 ]




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