Light scattering intensity measurements

It can be shown that the weight-average molecular weight can be determined from the ratio of the area of the light-scattering intensity measured at low angle, <10°, and the concentration chromatograms, corrected for their respective calibration constants (29) ... 

Salt, K. Noble, C. A. Prather, K. A. Aerodynamic particle sizing versus light scattering intensity measurement as methods for real-time particle sizing coupled with time-of-flight mass spectrometry. Anal. Chem. 1996, 68, 230-234. 

All factors related to the arrangement of the polymer chain in space are classified as tertiary structure. Parameters measurable directly (the radius of gyration RG, the end-to end distance h, the hydrodynamical radius RH, and the asymmetry in light scattering intensity) or indirectly (interaction parameters, the second virial coefficient A2) are related to the dimensions, such as size and shape of the polymer chain in a specific solvent under given conditions of temperature and pressure. For the exact determination of the coil size of macromolecules, it is necessary to ensure that measure-... 

It is instructive to make a quantitative comparison between the experimental and theoretical curves. The light scattering intensity, expressed as the Rayleigh ratio, is a function of the size and number of particles. If all three reactions shown in Figure 7 polymerize at the same rate, Rp, then at a given time, say 10 seconds, the total volume of polymer formed, VT, will be the same in all three. Under these conditions, the scattering intensity becomes a direct measure of the relative number of particles ... 

Equation (6.29) is the governing equation for the use of homodyne, dynamic light scattering for measurement of velocity gradients. What is left is to specify the shape of the intensity distribution of the incident light within the scattering volume. As an example, if... 

Fig. 7 Evolution of the light scattering intensity for PFS54-6-PDMS945 solutions at 1.0mg/mL in -hexane and in benzene (the dashed curve is used as a guide for the eyes). The measured intensity for each solution in hexane was divided by the measured intensity of the solution in benzene aged for an identical time. The inset shows the evolution of intensity over the first 60 min...

The use of wedge-shaped photodetectors to measure forward light scattering intensity has also been explored for determination of crystal shape [87]. 

TSI Aerodynamic particle size spectrometer model 3327provides two measurements, aerodynamie diameter and light-scattering intensity, in the size range 0.5 to 20 pm. The generation of paired data makes the instrument of partieular interest to aerosol scientists. 

T. Keyes and B. M. Ladanyi. Can dielectric theories and measurements be used to predict depolarized light scattering intensities Molec. Phys., 54 765-771 (1977). 

AMF, MF-TAG, and MF-DAG obtained from measurements of light-scattering intensities are shown in Figure 5. In this case, MF-TAG crystallized first, and AMF had the longest induction times. The induction times for the crystallization curves are reported in Table 2. 

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