Capacity ratio plot

An alert operating engineer must identify boiler tube leaks before it is too late. The capacity ratio plot (Fig. 5-3) is the key. A gradual increase in pressure drop is an early warning sign. When this happens, check for low steam production rates from the high-pressure boiler. Another tip-off is a low gas outlet temperature from this boiler. If both steam production and outlet temperature are low and pressure drop is high, shut down the plant. There is a tube leak. 

The function f(k ) is shown plotted against the thermodynamic capacity ratio in Figure 1. It is seen that for peaks having capacity ratios greater than about 2, the magnitude of (k ) has only a small effect on the optimum particle diameter because the efficiency required to effect the separation tends to a constant value for strongly retained peaks. From equation (1) it is seen that the optimum particle diameter varies as the square root of the solute diffusivity and the solvent viscosity. As, in... 

By using experimentally obtained data for 1 mM salicylic acid, a plot of reciprocal analytical signal versus reciprocal a, yielded a linear relationship for the pH range 1.65-3.01. This result supported the solvent extraction model. The corresponding estimate of capacity ratio and distribution coefficient using this treatment was 8.5. 

Here c and are the concentrations of the substance under test in the stationary and mobile phase respectively, F" and F are the volumes of the stationary and mobile phase in the column, and is the retention time of an inert substance. From measurements of and f the capacity ratio k, and from this the partition coefficient K, can be calculated. In Figure 37 experimentally determined log k values are plotted against the density p and the pressure p of supercritical carbon dioxide at 40 C as a mobile phase for SFC experiments with alkanes having between 10 and 30 carbon atoms a chemically bonded stationary phase (Carbowax 400 on Porasil C) was used and further details are given in the caption of Figure 37. > The curves show that with increasing density the retention time f and the capacity ratio k decrease and consequently the... 

In order to optimize a separation and produce it in the minimum time, the capacity ratios and separation ratios must be measured for a given pair of enantiomers under known conditions of mobile phase composition and temperature (this will be discussed in detail later in this chapter). Unfortunately, when two peaks are eluted close together, which frequently occurs in chiral chromatography, the positions of the peak maxima are distorted due to the immediate presence of the other peak. An example of this problem is shown in figure 10.1, where the peaks are simulated and added, and the composite envelope plotted over the envelope of each individual peak. It is seen that the actual retention difference, if taken from the maxima of the envelope, will give a value of less than 60% of the true retention difference. Unfortunately, this type of error will probably not be taken into account by most data processing software. It follows, that if such data is used in an attempt to calculate the... 

Thus, knowing the particle characteristics, R and e, and the slope of the linear isotherm, we can readily determine the effective diffusivity D. This method can be conveniently carried out with a simple linear plot, without recourse to any numerical optimization procedures (provided, of course, that the capacity ratio B is known beforehand). 

An example that has been obtained recently is shown in Fig. 23, where log k[ values are plotted against the density of the pure mobile phase (Fig. 23a), and the reciprocal absolute temperature (Fig. 23b) for some selected hexa-substituted benzenes as samples [40,62]. Such curves will be important for the separation by SFE or by analytical and/or preparative SFC. Fig. 23a also demonstrates a well-known tendency in SFC With increasing density of the mobile phase capacity ratios (and consequently retention times) decrease, but the selectivities (characterized by a j = k[/ ) normally also change and might approach unity with increasing density. For hexachlorobenzene and hexamethylbenzene the log k[ p) isotherms even intersect (Fig. 23a). As a consequence, k[/ and = taj at the intersection point, and the substances cannot be separated by SFC under these conditions. Thus, Fig. 23a demonstrates that a compromise between retention time and selectivity has to be found in each individual application. 

In Fig. 24c, log k[ values calculated from retention times with the use of Equation (6) at a constant density of 0.44 g cm (same density as in Fig. 24a) are plotted as a function of the reciprocal absolute temperature, and in Fig. 24b at a constant temperature of 395 K against the density of the mobile phase. Within the ranges of the experiments, both plots give nice straight lines. These findings are, for example, of interest for the estimation and correlation of capacity ratios (and by this of retention times) and consequently for the development of index systems similar to those used in gas chromatography. 

Although it is important that no water should exist in the cathode materials of nonaqueous batteries, the presence of a little water is unavoidable when Mn02 is used as the active material. It is believed that this water is bound in the crystal structure, and that it has no effect on the storage characteristics, as shown in Figure 2.27, where the relationship of the Mn02 heat-treatment temperature to the residual capacity ratio after 11 months of storage at 60 °C is plotted. 

Fig. 32. Reversible capacity of microporous carbon prepared from phenolic resins heated between 940 to 1 I00°C plotted as a function of the X-ray ratio R. R is a parameter which is empirically correlated to the fraction of single-layer graphene sheets in the samples.

The most difficult feature of this method is that for each type of plant or plant product as well as for each type of equipment there is a break-point where the 0.6 no longer correlates the change in capacity. For small equipment or plants in reasonable pilot or semi-works size, the slope of the cost curve increases and the cost ratio is greater than 0.6, sometimes 0.75, 0.8 or 0.9. From several cost values for respective capacities a log-log plot of capacity versus cost will indicate the proper exponent by the slope of the resultant curve. Extrapolation beyond eight or ten fold is usually not too accurate. 

Figure 5.1 is a graph of the specific heat capacity cp (heat capacity per gram) of aqueous sulfuric acid solutions at T — 298.15 K against A, the ratio of moles of water to moles of sulfuric acid. The values plotted were obtained from a very... 

In Figure 264 the dehumidification potential A7 of a 40% LiCl-F O solution is plotted as a function of the air to solution mass flow ratio MR for certain operating conditions and ideal mass exchange, solid line (1). In addition the energy storage capacity SC is plotted, dotted line (2). Up to a... 

DRIFT spectroscopy was used to determine Av0h shifts, induced by adsorption of N2 and hexane for zeolite H-ZSM-5 (ZSM-a and ZSM-b, Si/Al=15.5 and 26), H-mordenite (Mor-a and Mor-b, Si/AI— 6.8 and 10) and H-Y (Y-a and Y-b, Si/Al=2.5 and 10.4) samples. Catalysts were activated in 02 flow at 773 K in situ in the DRIFTS cell and contacted than with N2 at pressures up to 9 bar at 298 K or with 6.1% hexane/He mixture at 553 K, i.e., under reaction conditions. Catalytic activities of the solids were measured in a flow-through microreactor and kapp was obtained as slope of -ln(l-X0) vs. W/F plots. The concentration of Bronsted acid sites was determined by measuring the NH4+ ion-exchange capacity of the zeolite. The site specific apparent rate constant, TOFBapp, was obtained as the ratio of kapp and the concentration of Bronsted acid sites. 

We see m[>L. is the reciprocal slope of the best-fit line in a plot of Se04 / >L Se07 versus flse04, and K is the ratio of the line s intercept to its slope. The sorption capacity, in mol g 1 soil, then, is given nw ntT LJns. 

The plots of AG° vs. for differentratios, calculated from the model proposed in Refs. 148, 151, and 152 are presented in Fig.lO. The calculation was made for n = 2, the area occupied by one water molecule equal to 0.09 nm, and for other double-layer parameters that best fit the experimental data on differential capacity of the Hg/water interface. As follows from these plots, no tZmax of adsorption can be reached if the Hfj/n ratio is greater than the dipole moment of water (1.84 D). 

FIGURE 7 Peak capacity plots for columns of equal ratio of column length to particle size (a) 5pm 5cm, (b) 3 im 3cm, (c) 2p,m 2cm. 

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