Linear normal dispersion

When the intensity of the probe beam (/ ) is low, the linear normal dispersion term dominates, so... 

In the years to follow the key to the measurement of vibrational circular dichroism was the development of photoelastic modulators suitable for work in the infrared spectral region. The first successful measurements of circular dichroism originating from vibrational transitions in the infrared were done by Hsu and Holzwarth (1973) on thin slices of monocrystalline a-NiS04 6 H2O and a-ZnSe04 6 H2O. For this measurements the authors used a normal dispersive IR spectrometer supplemented by a linear polarizer and a photoelastic modulator made from Germanium. 

Straight calibration curves for NADH over at least three orders of magnitude were obtained between pH 6 and 9 with phenoxazine CMEs as sensors in flow systems despite the decreasing reaction rate. As long as the effective NADH-concentration at the electrodesolution interface is well below the KM-value a linear response characteristic is expected. Km-values in the millimolar level have been obtained for most phenoxazines. When using phenoxazine-CME as sensors in FIA-systems with normal dispersion factors of about 10 the upper linear response range is expected around 10-30 mM. 

The linear regression applied to the data sets obtained over each plateau should be characterized by a slope as close as possible to 0. The normal dispersion (four times the standard deviation) of experimental data acquired over each plateau should correspond to a maximum 0.5% variation of the %S2 (such acceptance criteria is known as ripple). For SDS especially featured for sensitive applications (including micro or nano ones), the same algorithm may be applied for 1% or even 0.1% modification steps for the S2 channel. Reducing the amplitude of the step gradient should be compensated by a proportional increase of the UV tracer in the S2 channel. Some differences in ripple for 0.1% and 1% gradient steps are illustrated in... 

A first approach to the definition of the confidence regions in parameter space follows the linear approximation to the parameter joint distribution that we have already used If the estimates are approximately normally distributed around 9 with dispersion [U. U.] then an approximate 100(1 - a)%... 

A microgel is an intramolecularly crosslinked macromolecule which is dispersed in normal or colloidal solutions, in which, depending on the degree of crosslinking and on the nature of the solvent, it is more or less swollen. Besides linear and branched macromolecules and crosslinked polymers, intramolecularly crosslinked macromolecules may be considered as a fourth class of macromolecules. 

Of course, as q increases, the dispersion law ru q) deviates from linear, so that the integral over q in Eq. (A1.65) should be limited from above. It is reasonable to so limit the admissible frequencies a> that the state density normalization (A 1.27) is preserved ... 

The value of (H) for each solute was determined in each solvent mixture over 10 different linear velocities that covered the normal practical range of velocities used in LC. Measurements at each velocity were taken in triplicate which resulted in a minimum of 180 values of (H) being taken for each solute. Each data set, from each solvent mixture, was fitted to each dispersion equation and the values for the respective constants (A), (B), (C), etc. calculated, together with the index of determination for each fitting, it ia seen that the data was sufficient in both quantity, and quality to be able to dentify the most appropriate dispersion equation with some confidence. The results obtained are shown in table 2. 

The flow rate is employed as the independent variable, an alternative to the more usual linear velocity, as the flow rate is defined by the column with which the low dispersion tubing is to be used. It will be shown in due course that the column flow rate is independently defined by the nature of the separation that is to be achieved by the column, It is seen that a similar curve is obtained for the serpentine tube, as that for the coiled tube, but the the maximum value of (H) is reached at a much lower flow rate than that with the coiled tube. Furthermore, the variance remains more or less constant over a wide range of flow rates that encompass those usually employed in normal LC separations. 

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