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Inverse relationships

From the arguments of the present section it is clear that an inverse relationship holds between the specific surface and the particle size, and if the particles are long or thin it is the minimum dimension, the thickness of the plates or of the rods, which mainly determines the magnitude of the specific surface. [Pg.35]

One of the most important uses of specific surface determination is for the estimation of the particles size of finely divided solids the inverse relationship between these two properties has already been dealt with at some length. The adsorption method is particularly relevant to powders having particle sizes below about 1 pm, where methods based on the optical microscope are inapplicable. If, as is usually the case, the powder has a raiige of particle sizes, the specific surface will lead to a mean particle size directly, whereas in any microscopic method, whether optical or electron-optical, a large number of particles, constituting a representative sample, would have to be examined and the mean size then calculated. [Pg.37]

Quantitative Calculations In a quantitative analysis, the height or area of an analyte s chromatographic peak is used to determine its concentration. Although peak height is easy to measure, its utility is limited by the inverse relationship between the height and width of a chromatographic peak. Unless chromatographic conditions are carefully controlled to maintain a constant column efficiency, variations in... [Pg.572]

Rate of polymerization. The rate of polymerization for homogeneous systems closely resembles anionic polymerization. For heterogeneous systems the concentration of alkylated transition metal sites on the surface appears in the rate law. The latter depends on the particle size of the solid catalyst and may be complicated by sites of various degrees of activity. There is sometimes an inverse relationship between the degree of stereoregularity produced by a catalyst and the rate at which polymerization occurs. [Pg.490]

Thus, for a set K, an inverse relationship between pass energy, and sht width, w, exists. Retardation with a CFIA can either be in the CAE or CRR modes. This retardation is accomphshed by planar retarding grids placed across the entrance aperture of the CFIA. [Pg.284]

Because of its low permeabiUty, FEP polymer is used extensively in the chemical industry. Its permeation characteristics are similar to those of PTFE (Table 4). An inverse relationship between permeabiUty and film thickness appHes to FEP. [Pg.361]

Up to 80% of oral doses of ascorbic acid are absorbed in humans with intakes of less than 0.2 g of vitamin C. Absorption of pharmacological doses ranging from 0.2 g to 12 g results in an inverse relationship, with less than 20% absorption at the higher doses. A single oral dose of 3 g has been reported to approach the absorptive capacity (tissue saturation) of the human intestine. Higher blood levels can be attained by providing multiple divided vitamin C doses per day. [Pg.22]

Decrease hinder viscosity. Lower hinder concentration. Change hinder. Decrease any diluents and polymers which act as thickeners. Raise temperature for processes without simultaneous drying. Lower temperature for processes with simultaneous drying since hinder concentration will decrease due to increased hqiiid loading. This effect generally offsets inverse relationship between viscosity and temperature. [Pg.1881]

Figure 2.15(a) shows the relationship between and Cp for the component characteristics analysed. Note, there are six points at q = 9, Cp = 0. The correlation coefficient, r, between two sets of variables is a measure of the degree of (linear) association. A correlation coefficient of 1 indicates that the association is deterministic. A negative value indicates an inverse relationship. The data points have a correlation coefficient, r = —0.984. It is evident that the component manufacturing variability risks analysis is satisfactorily modelling the occurrence of manufacturing variability for the components tested. [Pg.57]

A eorrelation eoeffieient of 1 indieates that there is a very strong assoeiation between the two variables as shown in Figure 4.8. Lower values of r indieate that the variables have less of an assoeiation until at r = 0, no eorrelation between the variables is evident. A negative value indieates an inverse relationship. Therefore, the maximum value of eorrelation eoeffieient for eaeh linear reetifieation model will give most appropriate distribution that fits the sample data. [Pg.144]

NB There is some evidence of an inverse relationship between coffee drinking and cancer of the large bowel coffee drinking could not be classified as to its carcinogenicity to other organs)... [Pg.104]

Charged macromolecules, such as proteins or polymers, are often separated elec-trophoretically. The rate of migration through an electric field increases with net charge and field strength. Molecular size of analytes and viscosity of separation media both have inverse relationships with rate of migration. These variables must all be taken into account in order to optimize the conditions for an efficient electrophoretic separation. [Pg.197]

Ionic liquid conductivity appears to be most strongly correlated with viscosity (q). Figure 3.6-3 shows a plot of conductivity versus viscosity for the data in Tables 3.6-3-3.6-5. This figure clearly demonstrates an inverse relationship between conductivity and viscosity. [Pg.117]

As mentioned earlier, there is an inverse relationship between water volumes and oxygen concentration in soil. As soils dry, conditions become more aerobic and oxygen diffusion rates become higher. The wet-dry or anaerobic-aerobic alternation, either temporal or spatial, leads to higher corrosion rates than would be obtained within a constant environment. Oxygen-concentration-cell formation is enhanced. This same fluctuation in water and air relations also leads to greater variation in biological activity within the soil. [Pg.382]

The inverse relationship between dissolved solids concentration and pressure is illustrated by the figures given for low-pressure boiler waters in Table 17.6. That there is room for different opinions is shown by contrasting the BSS and ASME recommendations. Whilst both of these authorities propose essentially similar figures for feed-water (Table 17.7), some of the ASME boiler-water figures are substantially below their BS equivalents. This is probably due to the increasing trend towards higher heat fluxes than formerly in some low-pressure plant, particularly waste-heat boilers. [Pg.851]

Evidently a linear inverse relationship exists between molecular weights and initiator concentration. This effect is certainly due to efficient chain transfer to the initiator ... [Pg.45]

Experimental correlations have been established in a given LDL formulation between foam stability and interfacial tension [33]. For example, Fig. 15 shows the effect of increasing water hardness on plate washing performance of an LAS/AES blend. A small amount of Ca2+ ion helps substantially to stabilize the foam. Under the same conditions interfacial tension is also lowered substantially. The two curves show an inverse relationship where the minimum interfacial tension value corresponds to the optimum level of foam stability as measured by plate washing [33]. [Pg.128]

The structure factor for the 104-atom complex with almost perfect icosahedral symmetry determines the intensities of the diffraction maxima, in correspondence with the inverse relationship between intensity in reciprocal space and the atom-pair vectors in real space that was discovered fifty years ago by Patterson.27 The icosahedral nature of the clusters in the cubic crystal explains the appearance of the Fibonacci numbers and the golden ratio. [Pg.839]

Considerable effort has been expended on Ag atoms and small, silver clusters. Bates and Gruen (10) studied the spectra of sputtered silver atoms (a metal target was bombarded with a beam of 2-keV, argon ions produced with a sputter ion-gun) isolated in D, Ne, and N2. They found that an inverse relationship between Zett of the metal atom and the polarizability of rare-gas matrices (as determined from examination of... [Pg.92]


See other pages where Inverse relationships is mentioned: [Pg.554]    [Pg.338]    [Pg.404]    [Pg.438]    [Pg.390]    [Pg.194]    [Pg.77]    [Pg.490]    [Pg.455]    [Pg.453]    [Pg.374]    [Pg.352]    [Pg.1727]    [Pg.128]    [Pg.33]    [Pg.141]    [Pg.43]    [Pg.167]    [Pg.338]    [Pg.401]    [Pg.114]    [Pg.105]    [Pg.692]    [Pg.52]    [Pg.318]    [Pg.377]    [Pg.257]    [Pg.75]    [Pg.63]    [Pg.232]    [Pg.80]    [Pg.86]   
See also in sourсe #XX -- [ Pg.33 ]

See also in sourсe #XX -- [ Pg.184 , Pg.212 ]

See also in sourсe #XX -- [ Pg.182 ]

See also in sourсe #XX -- [ Pg.261 ]




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