Detector multi angle

FIGURE 6.39 Hydroxyethyl cellulose. Column Left Shodex OHpak SB-806 HQ, 8.0 mm i.d. x 300 mm. Right Shodex Asahipak GF-710 HQ, 7.6 mm i.d. x 300 mm. Eluent 100 mA1 NaNOj. Flow rate 1.0 mL/min. Detector Multi-angle laser light scattering detector. Column temp. 40°C. Sample 0.05%, 200 /iL, Hydroxyethyl cellulose. 

FIGURE 6.4 Comparison of Shodex GPC UT column and conventional-type column. Column Left Shodex GPC UT-806M X 2, 8 mm i.d. X 300 mm X 2. Right Conventional type column X 2, 7.8 mm i.d. X 300 mm x 2. Eluent 0.1% BHT in ODCB. Flow rate 1.0 mL/min. Detector Rl, MALLS (multi-angle laser light scattering detector). Column temp. I45°C. Sample High-density polyethylene. 

Recent advances have greatly decreased the difficulties raised by these cautionary points. In particular, on-line viscosimetry and multi-angle lightscattering make it possible to determine the molecular weight and viscosity of samples as a function of elution volume. With such detectors, effects of solute-column packing interactions become unimportant, since the properties of narrow fractions can be measured. These detectors will be discussed in greater detail below. 

Determined by SEC analysis using a multi-angle laser light scattering detector. 

Fig. 3 GPC setup for functional group profiling. RI refractive index detector Fluorescence fluorescence detector MALLS multi-angle laser light scattering detector...

Malvern Compact Goniometer System (CGS-3) is a multi-angle light scattering spectrometer. The detector scans a sample cell from an angle of 12° to 152° with an angular resolution of 0.025°. 

The CALLS detector is insensitive to low MW and low concentration species. Therefore, the determined by this method may be erroneously high. Another commercially available MW detector is a Multi Angle Laser Light Scattering (MALLS) photometer. It should be noted that a good chromatographic... 

Figure 2 The molar mass distributions of two hydroxypropyl-methyl cellulose (HPMC) batches (Metolose 60 SH 10 OOOcps, Shin-Etsu, Tokyo, Japan) determined with SEC connected online to multi-angle scattering (MALS) and refractometric (Rl) detectors. The broad distributions contain HPMC chains ranging from a few thousands up to several millions in molar mass. Despite the fact that the two batches belong to the same viscosity grade, significant differences are seen in the molar mass distributions. This emphasizes the importance of proper characterization of the complete molar mass distribution instead of only estimations via viscosity averages. (Reproduced with permission from Bengt Wittgren, Analytical Development, Astra Hassle/AstraZeneca, Moindal, R D Mbindal.)...

Figure 2.2 Typical setup of size-exclusion chromatography equipped with triple detection for determination of the moiecuiar weight of polymers without the need for prerequisite calibration. DRi, differential refractive index detector DV, differentiai viscometer I, injector MALS, multi-angle light-scattering detector (depending on the model, the scattered light is measured at 3 or 18 different angles) P, pump. The central unit includes a computer and software.

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