Vs. concentration curves

Figure 7 shows the viscosity vs. concentration curves for PTF in various organic solvents. As would be expected, in toluene, the most polar among the four solvents, the viscosity was the lowest at any given concentration. Figure 8 shows the effect of concentration on the viscosity of C02 at 25°C. The observed 50% increase in viscosity is not sufficient for enhanced oil recovery operations. 

Figure 7. Viscosity vs. concentration curves for PTF in various solvents at 25°C. The number near each point...

Jarvis, N.L. and Zisman, W.A. "Surface Activity of Fluorinated Organic Compounds at Organic-Liquid/Air Interfaces Part II. Surface Tension vs Concentration Curves, Adsorption Isotherms, and Force-Area Isotherms for Partially Fluorinated Carboxylic Esters," Naval Research Labs Report 5364, Surface Chemistry Branch, Chemistry Division, October 8, 1959. 

The kinetics results of the batch reactor runs lead to the following qualitative observations At low CO pressures (less than about 1 atm) the catalysis appears to be first order in ruthenium over the range 0.018 M to 0.072 M and also in Pco as illustrated by the log Pco vs time plots of Fig. 2 and also shown by the method of initial rates. Changes in the sulfuric acid and water concentrations over the respective ranges 0.25 M to 2.0 M and 4 M to 12 M have relatively small effects on the catalysis rates, although the functionalities are complicated and show concave rate vs concentration curves with maximum rates... 

Fig. 3-19. Proton level vs. concentration curves of addic proton (Hs0 /H20) and acetic proton (HAc/Ac") unitary acetic proton level ( H (Hso /At-)= proton levels in...

Higher tangential veloceties (or recirculation rates) should decrease the boundary layer thickness (6) and increase the mass transfer coefficient (k) in Equation 3 resulting in higher slopes of the flux vs concentration curve (Figure 11) without changing the gel-concentration. 

Octadecanol was recrystallized from hexane after fractionation by vacuum distillation, and its purity was checked by gas-liquid chromatography. Dodecylammonium chloride was recrystallized from a mixture of ethanol and water, and its purity was confirmed by the fact that it had no minimum near the critical micelle concentration on the surface tension vs concentration curve. Hexane was distilled after passing through an activated alumina column. Water was distilled from alkaline permanganate solution of distilled water after refluxing for one day. The purity of hexane and water was confirmed by the value of the interfacial tension between them. 

Linearity of Response and Reaction Products. The response vs. concentration curves obtained for CO, NO and NO2 gas sensor cells are depicted in Figures 5, 6 and 7 respectively. In all instances good linearity over the range studied was observed between current and partial pressure of each of the above gases (as depicted by equation (k)). The proportionality constants, K, with standard de-... 

A new theory of electrolyte solutions is described. This theory is based on a Debye-Hiickel model and modified to allow for the mutual polarization of ions. From a general solution of the linearized Poisson-Boltzmann equation, an expression is derived for the activity coefficient of a central polarized ion in an ionic atmosphere of non-spherical symmetry that reduces to the Debye-Hiickel limiting laws at infinite dilution. A method for the simultaneous charging of an ion and its ionic cloud is developed to allow for ionic polarization. Comparison of the calculated activity coefficients with experimental values shows that the characteristic shapes of the log y vs. concentration curves are well represented by the theory up to moderately high concentrations. Some consequences in relation to the structure of electrolyte solutions are discussed. 

Sensitization of Ti02 nanosized particle films soaked in water was tried by dissolving a sensitizer and a sacrificial electron donor (EDTA) in the water phase (Fig. 19.7). Photocurrent was strongly dependent on the concentration of Ru(bpy)32+, reaching saturation at higher concentrations beyond 2 mM. By analysis of the photocurrent-vs.-concentration curve, a Langmuir-type adsorption of the dye was suggested. 

The volume expansions of alkali metals in liquid ammonia are discussed in the light of the current available data. Special emphasis is made of the anomalous volume minimum found with sodium-ammonia and potassium-ammonia solutions. Recent studies of potassium in ammonia at —34° C. were found to exhibit a large minimum in the volume expansion, AV, vs. concentration curve. The results of these findings were compared with the previous results of potassium in ammonia at —45° C. The volume minimum was found to be temperature dependent in that the depth of the minimum increased and shifted to higher concentrations with increasing temperature. No temperature effect was observed on either side of the minimum. These findings are discussed in light of the Arnold and Patterson and Symons models for metal-ammonia solutions. 

Curve 1 is a plot of data from the investigation of Filbert (8) at —45° C. Filbert s results show a pronounced minimum in the volume expansion vs. concentration curve at 0.0AN. The AV value at the minimum is 30 cc./gram-atom as compared with the limiting value of approximately 42 cc./gram-atom at infinite dilution. 

As the amount of the surfactant in water is increased, the interface saturates to a point beyond which no further decrease in the interfacial tension occurs. At this concentration, the surfactant molecules start forming micelles (see Section 4.2.6). The inflection point of the interfacial tension vs. concentration curve is called the critical micelle concentration. 

Second, the spatially periodic model suggests further interpretations and experiments. That no kink exists in the viscosity vs. concentration curve may be related to the fact that the average dissipation rate remains finite at the maximum kinematic concentration limit, ma>. Infinite strings of particles are formed at this limit. It may thus be said that although the geometry percolates, the resulting fields themselves do not, at least not within the context of the spatially periodic suspension model. 

For a reversible sensor, sensitivity is defined as the change in sensor output signal obtained for an incremental change in the concentration or mass of the analyte, i.e., the slope of the response-vs-concentration curve. Sensitivity for a reversible AW sensor typically has units of [frequency change]/[concentration change], e.g., Hz/M (M mol/L), Hz/(/ug/L), or even ppm >pm (normalized frequency shift/concentration). For an irreversible sensor, sensitivity is more appropriately defined in terms of frequency change/integrated exposure, e.g., Hz/M-min. 

The shape of the polish rate vs. concentration curves in Figures 7.18 and 7.21 indicate that at low etchant concentrations, the polish rate is approximately linearly dependent on the etchant... 

This solution uses the reciprocal rate vs. concentration curve developed in part b) of problem 13-8 and shown below. The term best arrangemenf is used to mean the combination of the given reactors that gives the greatest degree of conversion for the given reactor sizes and types, and the flowrate and conditions of part b), problem 13-8. 

Each of the reactor types and volumes suggested in parts a) through d), will be matched with the reciprocal rate vs. concentration curve to find the lowest concentration achievable. 

Membrane Flux Performance for the Hollow Fiber Units. Figures 3a and 3b show the results of a cell separation pilot scale run in which transmembrane pressure was maintained constant at 4.0 psi and linear velocity through the fibers was maintained at 1.0 m/sec (100 1pm). Transmembrane pressure was controlled with a backpressure valve on the combined permeates from the hollow fibers. Note that the flux vs. concentration curve for this run does not conform to theoretical predictions for concentration polarization (see Figure 3b). Flux on this semi-log plot does not decline linearly, but, rather, shows two phases of fouling. The initial phase (approximately 20 minutes in duration) is characterized by a rapid loss in flux, while the second stage (approximately 90 minutes in duration) is more gradual. The initially rapid decline caused an unacceptably low average flux of 10 l/m -hr. 

Figure 46. Surface pressure vs. concentration curves for adsorption of diethyl ether on gold faces (in 10 mM NaF). ...

Figure 2. Signal vs. concentration curves for N -saturated solutions at different pH values...

As with N20 the shapes of yield vs. concentration curves show little or no dependence on dose rate. As stated this is to be expected if these reactions occur in or near spurs. Again the difference between the cyclohexene yield and the bicyclohexyl yields is greater than that caused by unimolecular dissociation, implying that SF6 like N20 does not affect the yield of thermal hydrogen atoms. 

The scatter is no less than in Figure 2.2 and the extra points do little to constrain the behaviour of the rate vs. concentration curve. If we superimpose Figures 2.2 and 2.6 we see that the scatter is similar in the two sets of experiments, and their delineation of the true behaviour of the underlying behaviour is inadequate in both cases. The additional points obtained in the PFR have brought us no closer to understanding the kinetics of this simple reaction. 

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