Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Mobility relationship between

Gliding mutants of Mycoplasma mobile-, relationships between motility and cell morphology, cell adhesion, and microcolony formation. Microbiology 146, 1311-1320. [Pg.197]

The presence of surface conductance behind the slip plane alters the relationships between the various electrokinetic phenomena [83, 84] further complications arise in solvent mixtures [85]. Surface conductance can have a profound effect on the streaming current and electrophoretic mobility of polymer latices [86, 87]. In order to obtain an accurate interpretation of the electrostatic properties of a suspension, one must perform more than one type of electrokinetic experiment. One novel approach is to measure electrophoretic mobility and dielectric spectroscopy in a single instrument [88]. [Pg.189]

Nonideal asymmetrical chromatographic bands showing (a) fronting and (b) tailing. Also depicted are the corresponding sorption isotherms showing the relationship between the concentration of solute in the stationary phase as a function of its concentration in the mobile phase. [Pg.555]

There is some disagreement on the correct equation for describing the relationship between plate height and mobile-phase velocity. In addition to the van Deemter equation (equation 12.28), another equation is that proposed by Hawkes... [Pg.562]

Water content indirectly affects other lens characteristics. Water evaporation from the lens can result in a dry eye sensation and subsequent desiccative erosion of the cornea. Clinical studies have shown the incidence of corneal erosion as a result of lens desiccation to be a material-dependent and water-content-dependent phenomenon (25,26). The nature of water and sodium ions in hydrogels has been studied primarily by nmr and thermal techniques (27,28). An empirical relationship between water mobility in contact lens polymers and desiccative staining has been proposed (29). [Pg.101]

The ion transport number is defined as the fraction of current carried through the membrane by counterions. If the concentration of fixed charges in the membrane is high compared to the concentration of the ambient solution, then the mobile ions in the IX membrane are mosdy counterions, co-ions are effectively excluded, and the ion transport number then approaches 1. Commercial membranes have ion transport numbers in dilute solutions of ca 0.85—0.95. The relationship between ion transport number and current efficiency is shown in Figure 3 where is the fraction of current carried by the counterions (anions) through the AX membrane and is the fraction of current carried by the counterions (cations) through the CX membrane. The remainder of the current (1 — in the case of the AX membranes and (1 — in the case of the CX membranes is carried by co-ions and... [Pg.173]

The seeond problem is the relationship between the position of the substituent in the pyrazole nueleus and its mobility. In the 1-phenylpyrazole series in their reaetions with Grignard reagents, the bromine reaetivity deereases in the order 5-Br>4-Br>3-Br (B-76MI40402). When an eleetron-withdrawing group is present at the 4-position, the 5-ehloropyrazole is more reaetive than 3-ehloropyrazole, but this has been attributed to bond fixation (Seetion 4.02.3.9). Thus, this problem needs further elarifieation. [Pg.267]

Scott and Beesley [2] measured the corrected retention volumes of the enantiomers of 4-benzyl-2-oxazolidinone employing hexane/ethanol mixtures as the mobile phase and correlated the corrected retention volume of each isomer to the reciprocal of the volume fraction of ethanol. The results they obtained at 25°C are shown in Figure 8. It is seen that the correlation is excellent and was equally so for four other temperatures that were examined. From the same experiments carried out at different absolute temperatures (T) and at different volume fractions of ethanol (c), the effect of temperature and mobile composition was identified using the equation for the free energy of distribution and the reciprocal relationship between the solvent composition and retention. [Pg.158]

Nuclear dipole-dipole interaction is a veiy important relaxation mechanism, and this is reflected in the relationship between 7, and the number of protons bonded to a carbon. The motional effect is nicely shown by tbe 7 values for n-decanol, which suggest that the polar end of the molecule is less mobile than the hydrocarbon tail. Comparison of iso-octane with n-decanol shows that the entire iso-octane molecule is subject to more rapid molecular motion than is n-decanol—compare the methyl group T values in these molecules. [Pg.176]

Fig. 11.13 Illustration of how mobile CA (here used to model elementary combat ) can be used to explore the relationship between primitive rules governing behavior on the micro-scale and emergent behavior on the macro-scale see text. Fig. 11.13 Illustration of how mobile CA (here used to model elementary combat ) can be used to explore the relationship between primitive rules governing behavior on the micro-scale and emergent behavior on the macro-scale see text.
The relationship between the ionic conductivity oi and the temperature T can either be derived from the diffusivity D or the mobility u assuming Arrhenius-type behavior ... [Pg.545]

The area of a peak is the integration of the peak height (concentration) with respect to time (volume flow of mobile phase) and thus is proportional to the total mass of solute eluted. Measurement of peak area accommodates peak asymmetry and even peak tailing without compromising the simple relationship between peak area and mass. Consequently, peak area measurements give more accurate results under conditions where the chromatography is not perfect and the peak profiles not truly Gaussian or Poisson. [Pg.266]

Unfortunately, neither the computer nor the potentiometric recorder measures the primary variable, volume of mobile phase, but does measure the secondary variable, time. This places stringent demands on the LC pump as the necessary accurate and proportional relationship between time and volume flow depends on a constant flow rate. Thus, peak area measurements should never be made unless a good quality pump is used to control the mobile phase flow rate. Furthermore, the pump must be a constant flow pump and not a constant pressure pump. [Pg.266]

Published refractive index data for the mobile phase, polystyrene, polyacrylonitrile, and the two monomers were used to calculate refractive index detector calibrations for the two homopolymers. The published data were used to determine relationship between refractive index increments of monomer and corresponding homopolymer. Chromatographic refractometer calibrations for the two homopelymers were then calculated from experimentally measured calibration data for the two monomers. [Pg.81]

The reactor was charged with 37 elastomer which was Insoluble In the chromatographic mobile phase. Thus, the relationship between calculated and measured solids contents should have, and did, differ by at least 37 at low conversions. Expected formation of Insoluble graft polymer would also have Influenced relationship between calculated and measured total solids. [Pg.83]

These arguments for simple electrolytes can be extended to the relationship between the two types of bound counterion in polyelectrolytes the bound but mobile (atmospheric) and the localized (site-bound). Under equilibrium conditions, the relationship between site-bound and atmospheric ions is... [Pg.68]

The adsorption mechanism in chromatography on alumina differs from that on silica gel because of the structural differences between these adsorbents. Relationships between the values of solutes and the adsorption data for the mobile phase components on sihca gel G and alumina G have been investigated by Rozylo [64,65]. The theoretical and experimental results obtained by the relation 2 = /( 1) show a good agreement for the two adsorbents. [Pg.88]

Prus and Kowalska [75] dealt with the optimization of separation quality in adsorption TLC with binary mobile phases of alcohol and hydrocarbons. They used the window diagrams to show the relationships between separation selectivity a and the mobile phase eomposition (volume fraction Xj of 2-propanol) that were caleulated on the basis of equations derived using Soezewiriski and Kowalska approaehes for three solute pairs. At the same time, they eompared the efficiency of the three different approaehes for the optimization of separation selectivity in reversed-phase TLC systems, using RP-2 stationary phase and methanol and water as the binary mobile phase. The window diagrams were performed presenting plots of a vs. volume fraetion Xj derived from the retention models of Snyder, Schoen-makers, and Kowalska [76]. [Pg.93]

Figure 1.3 Relationship between band broadening and mobile phase velocity (van Oeeater equation). (Reproduced with permission from ref. 48. Copyright Elsevier Scientific Publishing Co.)... Figure 1.3 Relationship between band broadening and mobile phase velocity (van Oeeater equation). (Reproduced with permission from ref. 48. Copyright Elsevier Scientific Publishing Co.)...

See other pages where Mobility relationship between is mentioned: [Pg.2882]    [Pg.773]    [Pg.62]    [Pg.399]    [Pg.355]    [Pg.358]    [Pg.220]    [Pg.224]    [Pg.163]    [Pg.261]    [Pg.352]    [Pg.915]    [Pg.1219]    [Pg.60]    [Pg.40]    [Pg.161]    [Pg.117]    [Pg.265]    [Pg.279]    [Pg.530]    [Pg.50]    [Pg.298]    [Pg.226]    [Pg.585]    [Pg.220]    [Pg.220]    [Pg.221]    [Pg.333]    [Pg.680]    [Pg.24]    [Pg.161]    [Pg.563]   
See also in sourсe #XX -- [ Pg.251 , Pg.252 , Pg.253 , Pg.254 , Pg.255 , Pg.256 , Pg.257 , Pg.258 , Pg.259 , Pg.260 ]




SEARCH



Relationships between mobile-phase velocity and column efficiency

© 2024 chempedia.info