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Total constants

A monolayer undergoes a first-order reaction to give products that also form monolayers. An equation that has been used under conditions of constant total area is (t - K°°)/(ifi - t") = exp(-)kr). Discuss what special circumstances are implied if this equation holds. [Pg.157]

Phase transitions in binary systems, nomially measured at constant pressure and composition, usually do not take place entirely at a single temperature, but rather extend over a finite but nonzero temperature range. Figure A2.5.3 shows a temperature-mole fraction T, x) phase diagram for one of the simplest of such examples, vaporization of an ideal liquid mixture to an ideal gas mixture, all at a fixed pressure, (e.g. 1 atm). Because there is an additional composition variable, the sample path shown in tlie figure is not only at constant pressure, but also at a constant total mole fraction, here chosen to be v = 1/2. [Pg.613]

The acidity constant for an organic weak acid was determined by measuring its absorbance as a function of pH while maintaining a constant total concentration of the acid. Using the data in the following table, determine the acidity constant for the organic weak acid. [Pg.455]

Fig. 2. The plot of total reduced iron, Fe, and oxidized iron, Fe, normalized to Si abundance shows how the chondrite classes fall into groups distinguished by oxidation state and total Fe Si ratio. The soHd diagonal lines delineate compositions having constant total Fe Si ratios of 0.6 and 0.8. The fractionation of total Fe Si is likely the result of the relative efficiencies of accumulation of metal and siUcate materials into the meteorite parent bodies. The variation in oxidation state is the result of conditions in the solar nebula when the soHds last reacted with gas. Terms are defined in Table 1 (3). Fig. 2. The plot of total reduced iron, Fe, and oxidized iron, Fe, normalized to Si abundance shows how the chondrite classes fall into groups distinguished by oxidation state and total Fe Si ratio. The soHd diagonal lines delineate compositions having constant total Fe Si ratios of 0.6 and 0.8. The fractionation of total Fe Si is likely the result of the relative efficiencies of accumulation of metal and siUcate materials into the meteorite parent bodies. The variation in oxidation state is the result of conditions in the solar nebula when the soHds last reacted with gas. Terms are defined in Table 1 (3).
An alternative mechanism involves a physical reorientation of particles at constant total volume to form clumps that have much larger pores (74). Electron micrographs of successive changes in morphology as a function of steeping time in hot water are offered in support of this interpretation. [Pg.478]

This example gives an indication of the small and usually acceptable variations found with a well-designed dual-duct system. Since a constant total flow is required with the basic dual-duct circuit, a single fan may be used, blowing into cooling and heating branches. Where variation of volume is employed, one or two fans may be used, as convenient for the circuit. In all cases an independent extract fan and duct system will be required, so that the proportion of outside/recirculated air can be controlled. [Pg.304]

The interaction between aequorin and a chelator must be carefully considered when estimating Ca2+ concentrations with aequorin in a calcium buffer containing EDTA or EGTA. This is particularly crucial when using a common calcium buffer system that contains a constant total concentration of a chelator in the buffer solutions of various Ca2+ concentrations in such a buffer system, a buffer of lower Ca2+ concentration contains a higher concentration of the free form of the chelator, resulting in an increased inhibition. [Pg.107]

If the distillation is carried out at constant total pressure (e.y., under atmospheric pressure) there will be, in general, a change of temperature, for if it were possible to separate a mixture into two parts of different composition at a constant temperature, we could remix these through semipermeable diaphragms and so... [Pg.380]

Figure 2.13 Mixing of ideal gas A with ideal gas B at constant temperature and constant total pressure. The entropy change AS is given by equation (2.78). Figure 2.13 Mixing of ideal gas A with ideal gas B at constant temperature and constant total pressure. The entropy change AS is given by equation (2.78).
The bromination of phenol in acetic acid, containing lithium bromide and perchlorate at a constant total concentration of 0.2 M, gave kinetic isotope effects... [Pg.126]

The raw output of a molecular structure calculation is a list of the coefficients of the atomic orbitals in each LCAO (linear combination of atomic orbitals) molecular orbital and the energies of the orbitals. The software commonly calculates dipole moments too. Various graphical representations are used to simplify the interpretation of the coefficients. Thus, a typical graphical representation of a molecular orbital uses stylized shapes (spheres for s-orbitals, for instance) to represent the basis set and then scales their size to indicate the value of the coefficient in the LCAO. Different signs of the wavefunctions are typically represented by different colors. The total electron density at any point (the sum of the squares of the occupied wavefunctions evaluated at that point) is commonly represented by an isodensity surface, a surface of constant total electron density. [Pg.700]

Fig. 15-17 The effect of chloride on adsorption of mercury by hydrous iron oxide at constant total mercury concentration of 3.4 x 10 M. The lines represent the predicted adsorption assuming that Hg-Cl complexes do not sorb at all. (Reprinted with permission from P. V. Avotins, Adsorption and coprecipitation studies of mercury on hydrous iron oxides," 1975, Ph.D. dissertation, Stanford University, Stanford, CA.)... Fig. 15-17 The effect of chloride on adsorption of mercury by hydrous iron oxide at constant total mercury concentration of 3.4 x 10 M. The lines represent the predicted adsorption assuming that Hg-Cl complexes do not sorb at all. (Reprinted with permission from P. V. Avotins, Adsorption and coprecipitation studies of mercury on hydrous iron oxides," 1975, Ph.D. dissertation, Stanford University, Stanford, CA.)...
If we make the same assumptions as above, i.e. constant total pressure and a stoichiometric gas mixture (N2 -r 3H2 at the start), we obtain... [Pg.35]

As an example of binary clusters for magnetic applications, we present the study performed on Ni-Co alloy [78]. The Co-Ni phase diagram was investigated by performing sequential ion implantation in silica of Co and Ni at the same energy of ISOkeV (Rp 150nm) but with different fluences in order to have a constant total Co+Ni fluence (15 x lO ions/cm or 30 x 10 ions/cm ). For the 1 1 Co Ni ratio, we also performed sequential implants at... [Pg.279]

The anhydrite saturation curve is drawn at constant total sulfate concentration and temperature. [Pg.301]

The SiHa H2 ratio was 20% 80% in all simulations. As most experiments in the ASTER deposition system are performed at a constant total power, the... [Pg.70]

The IR data suggest an anomalous decrease of the D157S/D 610 value with changing composition of the monomer mixture at constant total concentration of initial monomers. This concirms that the formation of a coordination complex between the carbonyl group and the tin atom at an equimolar TBSM-to-MA ratio is highly probable. [Pg.113]

Figure 6. pH dependence of (a) current density (on log scale) of oxygen ion incorporation into the oxide, at a constant total current density of 0.1 mA/cm2, and (b) the steady-state dissolution (aluminum ion) current density of oxide-covered aluminum at 4 V versus SCE.29... [Pg.414]

Dilution with argon at constant total pressure. [Pg.19]

The reaction is carried out isothermally in two flow reactors. Both reactors operate at a constant total pressure of 1 atm. [Pg.305]

Before proceeding to the next illustration, it is instructive to see if our assumption of constant total pressure was indeed appropriate. If one assumes 1/4 in. spherical pellets, a nominal gas viscosity of 0.09 lb/hr-ft and a bed porosity of 0.4, the Reynolds number of the gas is given by... [Pg.515]

Cote, G. Jakubiak, A. Bauer, D. Szymanowski, J. Mokili, B. Poitrenaud, C. Modeling of extraction equilibrium for copper(II) extraction bypyridinecarboxylic acid esters from concentrated chloride solutions at constant water activity and constant total concentration of ionic or molecular species dissolved in the aqueous solution. Solvent Extr. [Pg.801]

Gas diffusion in the nano-porous hydrophobic material under partial pressure gradient and at constant total pressure is theoretically and experimentally investigated. The dusty-gas model is used in which the porous media is presented as a system of hard spherical particles, uniformly distributed in the space. These particles are accepted as gas molecules with infinitely big mass. In the case of gas transport of two-component gas mixture (i = 1,2) the effective diffusion coefficient (Dj)eff of each of the... [Pg.141]

Figure 11. Projections of solid circulation rate at constant total flow and changing bed geometry—results of example calculation. Figure 11. Projections of solid circulation rate at constant total flow and changing bed geometry—results of example calculation.
Drag Elimination Rate Constant Total Body Clearance... [Pg.890]

Figure 5.56 illustrates the variation of NRT bond orders bef for reactant and product C—F bonds along the reaction coordinate, and Fig. 5.57 illustrates the corresponding variations of natural atomic charge on the two F atoms. Despite the numerical scatter, one can see in Fig. 5.56 that the reactant (6a0 and product (6cp) bond orders respectively diminish and increase while preserving approximately constant total bond order in the shifting toF Cp hyperbond,... [Pg.684]


See other pages where Total constants is mentioned: [Pg.621]    [Pg.18]    [Pg.317]    [Pg.381]    [Pg.498]    [Pg.1487]    [Pg.178]    [Pg.445]    [Pg.1359]    [Pg.16]    [Pg.32]    [Pg.168]    [Pg.96]    [Pg.340]    [Pg.637]    [Pg.284]    [Pg.452]    [Pg.18]    [Pg.411]    [Pg.97]    [Pg.240]    [Pg.251]    [Pg.485]    [Pg.139]   
See also in sourсe #XX -- [ Pg.174 ]




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Constant total molar overflow

Minimum trays, total reflux, constant volatility

Total Pressure at Constant Temperature

Total Quenching Rate Constants

Variation of Equilibrium Constant, K, with Overall Total Pressure

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