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Mobility approximation

If, a very large number of albumin molecules (mobility approximately -6.0 units) are placed in the glycine solution (pH 8.3), they will concentrate at the boundary between the chloride and the glycine at a concentration satisfying [equation 29-1] where a is now the serum albumin, p, the potassium ion, and y, the chloride ion. [Pg.347]

As we have already mentioned, liquid NH3 undergoes self-ionization (equation 8.12), and the small value of Aijeif (Table 8.4) indicates that the equilibrium lies far over to the left-hand side. The [NH4] and [NH2] ions have ionic mobilities approximately equal to those of alkali metal and halide ions. This contrasts with the situation in water, in which [H30]+ and [OH] are much more mobile than other singly charged ions. [Pg.218]

The charge (negative or positive net charge) of, e. g. a protein particle, is closely related to its electrophoretic mobility. Approximate information about the likely direction and magnitude of mobility of particles migrating in an electric field, can be obtained from titration results. There is, however, no quantitative agreement between the net charge as calculated from titration curves and from electrophoretic mobility. [Pg.107]

The mobility of these ions as a function of temperature is shown in Figure 20. A surprising aspect of these results is the fact that the negative ions exhibit a mobility approximately twice that of the positive ions. The electrostriction around the ion causes an increase in viscosity. In the case of negative ions, this effect is partly counterbalanced by the repulsive potential between the electron of the ion and the electrons of the solvent molecules/atoms (see Section 7.8). [Pg.120]

While with-in the mobile x-ray system, the waste in the sampler, is contained within a replaceable (and disposable) polyvinyl chloride (PVC) sleeve with a wall thickness of approximately 0.2-inches and a sealed bottom. It was anticipated that the PVC tube or sleeve would, with use, become highly contaminated with waste residues which drip of fall-off the sampler. The sleeve is coated with a conductive coating to prevent static electricity buildup . There are no sources of ignition in this sealed spare. The sampler (and waste) is coupling which includes a positive pressure gasket. This barrier is further isolated by a second barrier consisting of an epoxy coated aluminum sleeve also sealed-off from the main x-ray cabinet and PVC sleeve. There are also no potential sources of ignition in this isolated secondary space as well. [Pg.611]

One anomaly inmrediately obvious from table A2.4.2 is the much higher mobilities of the proton and hydroxide ions than expected from even the most approximate estimates of their ionic radii. The origin of this behaviour lies in the way hr which these ions can be acconmrodated into the water structure described above. Free protons cannot exist as such in aqueous solution the very small radius of the proton would lead to an enomrous electric field that would polarize any molecule, and in an aqueous solution the proton inmrediately... [Pg.574]

If there are no reactions, the conservation of the total quantity of each species dictates that the time dependence of is given by minus the divergence of the flux ps vs), where (vs) is the drift velocity of the species s. The latter is proportional to the average force acting locally on species s, which is the thermodynamic force, equal to minus the gradient of the thermodynamic potential. In the local coupling approximation the mobility appears as a proportionality constant M. For spontaneous processes near equilibrium it is important that a noise term T] t) is retained [146]. Thus dynamic equations of the form... [Pg.26]

A useful guide when using the polarity index is that a change in its value of 2 units corresponds to an approximate tenfold change in a solute s capacity factor. Thus, if k is 22 for the reverse-phase separation of a solute when using a mobile phase of water (P = 10.2), then switching to a 60 40 water-methanol mobile phase (P = 8.2) will decrease k to approximately 2.2. Note that the capacity factor decreases because we are switching from a more polar to a less polar mobile phase in a reverse-phase separation. [Pg.581]

Organic Solvent/H20 Mobile-Phase Compositions Having Approximately Equal Solvent Strength... [Pg.583]

First, solutes with larger electrophoretic mobilities (in the same direction as the electroosmotic flow) have greater efficiencies thus, smaller, more highly charged solutes are not only the first solutes to elute, but do so with greater efficiency. Second, efficiency in capillary electrophoresis is independent of the capillary s length. Typical theoretical plate counts are approximately 100,000-200,000 for capillary electrophoresis. [Pg.601]

Properties provided by the branched hydrocarbon chain stmcture of these PAO fluids include high viscosity index in the 130—150 range, pour points of —50 to —60° C for ISO 32 to 68 viscosity range (SAE lOW and SAE 20W, respectively), and high temperature stabifity superior to commercial petroleum products. In their use in automotive oils such as Mobil 1, some ester synthetic fluid is normally included in the formulation to provide sufficient solubihty for the approximately 20% additives now employed in many automotive oils. [Pg.245]

Mobilization and Metabolism. The total ascorbic acid body pool in healthy adults has been estimated to be approximately 1.5 g, which increases to 2.3—2.8 g with intakes of 200 mg/d (151—158). Depletion of the body pool to 600 mg initiates physiological changes, and signs of clinical scurvy are reported when the body pool falls below 300 mg (149). Approximately 3—4% of the body pool turns over daily, representing 40—60 mg/d of metabolized, or consumed, vitamin C. Smokers have a higher metaboHc turnover rate of vitamin C (approximately 100 mg/d) and a lower body pool than nonsmokers, unless compensated through increased daily intakes of vitamin C (159). The metaboHsm of ascorbic acid varies among different species. [Pg.22]

U.S. producers of benzene from petroleum and their approximate production capacities are shown in Table 5. These figures are inexact because the size of the market and instabiUty of benzene prices causes frequent changes in capacity. Dow Chemical, with total armual benzene capacity of 8.3 x 10 t (250 million gallons) is the largest producer in the United States. Other companies with total domestic capacity of over 3.3 x 10 t (100 million gallons) per year are Amoco Corp., Lyondell, British Petroleum America, Chevron, Exxon Chemical, Occidental Petroleum, Shell Oil, and Mobil. These companies account for approximately 60% of total U.S. benzene capacity (65). [Pg.43]

The first observation of the enantioselective properties of an albumin was made in 1958 (28) when it was discovered that the affinity for L-tryptophan exceeded that of the D-enantiomer by a factor of approximately 100. This led to more studies in 1973 of the separation of DL-tryptophan [54-12-6] C22H22N2O2, on BSA immobilized to Sepharose (29). After extensive investigation of the chromatographic behavior of numerous racemic compounds under different mobile-phase conditions, a BSA-SILICA hplc column (Resolvosil-R-BSA, Macherey-Nagel GmvH, Duren, Germany) was... [Pg.99]

In the special case that A and B are similar in molecular weight, polarity, and so on, the self-diffusion coefficients of pure A and B will be approximately equal to the mutual diffusivity, D g. Second, when A and B are the less mobile and more mobile components, respectively, their self-diffusion coefficients can be used as rough lower and upper bounds of the mutual diffusion coefficient. That is, < D g < Dg g. Third, it is a common means for evaluating diffusion for gases at high pressure. Self-diffusion in liquids has been studied by many [Easteal AIChE]. 30, 641 (1984), Ertl and Dullien, AIChE J. 19, 1215 (1973), and Vadovic and Colver, AIChE J. 18, 1264 (1972)]. [Pg.592]

Vertical Pumps In the chemical industiy, the term vertical process pump (Fig. 10-40) generally applies to a pump with a vertical shaft having a length from drive end to impeller of approximately 1 m (3.1 ft) minimum to 20 m (66 ft) or more. Vertical pumps are used as either wet-pit pumps (immersed) or dry-pit pumps (externally mounted) in conjunction with stationaiy or mobile tanlcj... [Pg.907]

We first consider strain localization as discussed in Section 6.1. The material deformation action is assumed to be confined to planes that are thin in comparison to their spacing d. Let the thickness of the deformation region be given by h then the amount of local plastic shear strain in the deformation is approximately Ji djh)y, where y is the macroscale plastic shear strain in the shock process. In a planar shock wave in materials of low strength y e, where e = 1 — Po/P is the volumetric strain. On the micromechanical scale y, is accommodated by the motion of dislocations, or y, bN v(z). The average separation of mobile dislocations is simply L = Every time a disloca-... [Pg.245]


See other pages where Mobility approximation is mentioned: [Pg.200]    [Pg.369]    [Pg.61]    [Pg.126]    [Pg.501]    [Pg.234]    [Pg.231]    [Pg.278]    [Pg.151]    [Pg.2127]    [Pg.206]    [Pg.113]    [Pg.381]    [Pg.204]    [Pg.63]    [Pg.200]    [Pg.369]    [Pg.61]    [Pg.126]    [Pg.501]    [Pg.234]    [Pg.231]    [Pg.278]    [Pg.151]    [Pg.2127]    [Pg.206]    [Pg.113]    [Pg.381]    [Pg.204]    [Pg.63]    [Pg.160]    [Pg.335]    [Pg.471]    [Pg.565]    [Pg.598]    [Pg.48]    [Pg.52]    [Pg.91]    [Pg.83]    [Pg.113]    [Pg.479]    [Pg.355]    [Pg.2063]    [Pg.160]    [Pg.318]    [Pg.224]    [Pg.7]    [Pg.96]   
See also in sourсe #XX -- [ Pg.334 ]




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Approximate Mobility Formula

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