Resolution correction

In homopolymer analysis this meant a closer study of the accuracy and reproducibility of data from GPC to see how resolution correction techniques could be either circumvented or practically applied. In copolymer analysis the limitation of conventional molecular size fractionation emerged as the fundamental difficulty. An orthogonal coupling of GPCs operated so as to achieve the desired cross fractionation before detection is presented as a novel approach with considerable potential. 

Sample Pairs D2 (Coxints ) DixlO-9 a (counts ) Imperfect Resolution Correction Factor... 

The relaxation function is measured directly as a function of time. Therefore, any instrumental resolution correction consists of a simple point by point division by the result of a measurement of a resolution sample, instead of a tedious deconvolution that would be required for S Q,co) measured at a real - finite resolution - instrument. 

Figure 1 Schematic diagram of calibration curve search with no resolution correction (a,b,c,d) and with direct resolution correction of the molecular weight averages (a,b,c,e,d). (Reproduced with permission from Ref. 1. Copyright 1984, Elsevier.)...

Another example of an equation nonlinear in the parameters is the sum of exponentials form vdiich is useful with some resolution correction methods ... 

Nonlinear regression enables broad molecular weight distribution standards to be used for SBC calibration and permits simultaneous resolution correction euid calibration. Furthermore, it greatly increases the variety of equations 4iich can be fit to calibration curves, detector linearity data and chromatogreun shapes. 

In deconvolution problems, such dominance is rarely the case. It is a very modest resolution correction indeed when the response function is so narrow that its central element dominates all the others. Fortunately, the necessary conditions are far less severe, and convergence is usually not a serious problem. Equation (25) seems to tell us, however, that each new row in the matrix brings more independent information when [s]ww/Sn9tw [s]ww is as large as possible. 

Figure 7. Crystalline peak resolution. Corrected and smoothed equatorial trace of a PET fiber specimen resolved into three crystalline peaks, 010, 110, 100, and...

Here, Cy is defined as the ratio of the corrected anisotropy Ang to the uncorrected one y stands for the lab-angle under which in the plane of the detector slit the full width at half intensity of the primary beam is seen from the scattering centre the wave number k, is calculated in the lab-system, for the primary beam molecules hkl = For NO this angular resolution correction amounts to about 10%, Stolte (1973). 

The differential cross sections reported in this paper are absolute measurements for an apparatus having our geometry and resolution. The geometrical and resolution corrections are dependent, to some extent, on knowledge of an intermolecular potential and are included in the theoretical calculations. The largest corrections are for the finite resolution of the detector. 

Any absolute measurements must include accurate knowledge of the number density of scattering centers. As a cross check on these figures, our measured total for argon, after resolution corrections, was 340 A, which is just within the experimental limits of Rothe s measured value of 319 A 7%. ... 

The important instrumental development of delayed (ion) extraction (DE) or time-lag focusing (TLF) [279] has had a great impact on MALDI development [280,281]. The major limitation to the resolution provided by MALDI-MS is the initial velocity distribution of the ions. Ions with the same mass/charge ratio but different energy distributions yield a broad peak with a decrease in resolution. Correction for this by the use of pulsed extraction for time-lag focusing [282] has greatly improved the quality of the mass spectra from low masses (<100 Da) up to high masses. The term time-lag... 

Thereby Snse(Q, 0 is the effective time-dependent polarization detected at the instmment. We note that the conversion of the ideal intensities to S(Q, f) under real experimental conditions need to consider polarization losses in the instmment that are measured in a reference experiment on a purely elastic scatterer. Such a measurement serves as a determination of the experimental resolution function. Since the experiments are performed in Fourier space instead of a deconvolution as required in sample data by the reference measurement. 

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