Laser scattering apparatus

Light scattering photographic patterns were obtained using a laser scattering apparatus as described by Rhodes and Stein. ... 

Fig. 7.18 (continued) (c) Light scattering apparatus used to detect polymer-polymer demixing 1 - HeNe laser, 2 - sapphire window, 3 - polymer film, 4 - photodiode array, 5 - copper block, 6 - resistance thermometer, 7 - temperature controlled jacket, (Reproduced with permission from Zywocinski, A., et al. J. Polymer Sci. Polym. Phys. 33, 595 (1995))... 

The static laser light scattering apparatus used as an on-line GPC detector has been popular for a while. Here, we illustrate another but less known method of combining the results from (gel permeation chromatography) and DLS. The basic principle is as follows There is a similarity between these two tools in that the translational diffusion coefficient D obtained by DLS and the elution volume V in GPC are related to the hydrodynamic size of a given macromolecule. In a first approximation, if the hydrodynamic size is proportional to the molar mass, we have... 

To conclude this section, we remark that the whole optical system, including the laser and light-scattering apparatus, is placed on a vibration isolation system to eliminate exterior vibrations. 

A typical laser diffraction apparatus is shown in I ig-ure 34-1. The beam from a continuous-wave (CW) laser, usually a Hc-Nc laser, is collimated and passed through the sample, where scattering from particles occurs, The beam is then focused on a detector array where llic scattering pattern, shown in Figure 34-1 as a diffraction pattern, is measured, The scattering pattern is then analyzed according to theoretical models to give the particle size distribution,... 

Nobbs, J.H. and Patterson, D. (1977) Studies of the kinetics of nucleation and growth of pigment dispersions using a laser light-scattering apparatus in a flow system. Journal of the Chemical Society Faraday Transactions, I 73, 558-568. 

In order to determine the crystal growth rate, volume-based particle size distributions were measured with a Horiba Laser Scattering Particle Size Distribution Analyzer LA-920. Additionally, BET surface area measurements of the seed crystals were undertaken with a Micromeritics Tristar Surface Area Analyzer. The crystal morphology was analyzed with a Philips XL30 PEG SEM. XRD analysis was carried out on a Bruker AXS powder diffractometer. Finally, chemical analysis was conducted with a Dionex ICS 5000 ion chromatograph and a Thermo Scientific iCAP 6000 ICP-MS apparatus. Thermodynamic calculations were conducted with the OLI Stream Analyzer [29]. To ensure reproducibility, the growth kinetics experiments were repeated three times and arithmetic averages were employed in the analysis of the data. 

Static light scattering Experiments were performed in glass cuvettes (0=21 mm) at 25 C on a PL-LSP light scattering apparatus equipped with a 10 mW laser (633 nm), and LSP Version 4.0 software (Polymer Laboratories). Measurements were... 

FIQURE 34- l Laser diffraction apparatus. When a particle enters a laser beam, light is scattered at an angle related to the particle size. The scattered light Is collected by a detector and the resulting scattering pattern Is analyzed. The scattering pattern of a group of different-size particles is, within limits, the summation of the patterns of the individual particles. 

Fig. 8.3. Schematic representation of crossed molecular beam scattering apparatus with laser ionization detection of the scattering product. Ion Imaging is used to measure the velocity of the laser-produced ions.

The molecular weight and its distribution have been determined by laser light scattering, employing a new apparatus for ETFE dissolution and solution clarification at high temperature diisobutyl adipate is the solvent at 240°C. The molecular weight of molten ETEE is determined by high temperature rheometry (21). 

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