Small-angle neutron scattering, SAN

The structure of microemulsions have been studied by a variety of experimental means. Scattering experiments yield the droplet size or persistence length (3-6 nm) for nonspherical phases. Small-angle neutron scattering (SANS) [123] and x-ray scattering [124] experiments are appropriate however, the isotopic substitution of D2O for H2O... 

SANS. See Small-angle neutron scattering (SANS)... 

Silylated diamines, 156, 187-188 Silylated monomers, 72 Silylation, distillation and, 338 6NT6 alternating polyesteramide, synthesizing, 189-190 6,6 -linked polymers, 480 Size exclusion chromatography (SEC) analyses, 90, 490 Slabstock foam, 233-234 Slow monomer addition, 57 Small-angle neutron scattering (SANS), 282... 

Small angle neutron scattering (SANS) involves firing neutrons at a sample and measuring the angle through which they are scattered. This allows the momentum transfer, Q, to be determined according to the equation ... 

The conformation of polymer chains in an ultra-thin film has been an attractive subject in the field of polymer physics. The chain conformation has been extensively discussed theoretically and experimentally [6-11] however, the experimental technique to study an ultra-thin film is limited because it is difficult to obtain a signal from a specimen due to the low sample volume. The conformation of polymer chains in an ultra-thin film has been examined by small angle neutron scattering (SANS), and contradictory results have been reported. With decreasing film thickness, the radius of gyration, Rg, parallel to the film plane increases when the thickness is less than the unperturbed chain dimension in the bulk state [12-14]. On the other hand, Jones et al. reported that a polystyrene chain in an ultra-thin film takes a Gaussian conformation with a similar in-plane Rg to that in the bulk state [15, 16]. 

Overview. Considerable research activities in the fields of isotropic SAXS and small-angle neutron scattering (SANS) are devoted to the investigation of ensembles of uncorrelated but identical or almost identical complex particles. Frequently these particles are studied in solution. Samples for such investigations must be supplied in a solution in which the particles do not aggregate. 

The size and shape of polymer chains joined in a crosslinked matrix can be measured in a small angle neutron scattering (SANS) experiment. This is a-chieved by labelling a small fraction of the prepolymer with deuterium to contrast strongly with the ordinary hydrogenous substance. The deformation of the polymer chains upon swelling or stretching of the network can also be determined and the results compared with predictions from the theory of rubber elasticity. 

Small angle neutron scattering (SANS) of "marked" (isotopically labeled) chains in unmarked networks has proven to be of potential value in... 

Time-resolved in situ Small Angle Neutron Scattering (SANS) investigations have provided direct experimental evidence for the initial steps in the formation of the SBA-15 mesoporous material, prepared using the non-ionic tri-block copolymer Pluronic 123 and TEOS as silica precursor. Upon time, three steps take place during the cooperative self-assembly of the Pluronic micelles and the silica species. First, the hydrolysis of TEOS is completed, without modifications of the Pluronic spherical micelles. Then, when silica species begin to interact with the micelles, a transformation from spherical to cylindrical micelles takes place before the precipitation of the ordered SBA-15 material. Lastly, the precipitation occurs and hybrid cylindrical micelles assemble into the two-dimensional hexagonal structure of SBA-15. 

Using small-angle neutron scattering (SANS), it was shown that alkoxy-substituted triphenylenes associate in deuterated hexadecane.70 At low concentrations small aggregates are formed and at higher concentrations (10 3 M)... 

Small-angle neutron scattering (SANS), 14 710, 19 568, 20 339 Small-angle X-ray scattering (saxs), 20 339, 341-342, 26 432 of amorphous silica, 22 474 Small beer, 26 471 Small Business Innovation Research (SBIR) program, 24 395, 399 Small Business Technology Transfer (STTR) program, 24 395 Small communities... 

Characterization of Dendritically Branched Polymers by Small Angle Neutron Scattering (SANS), Small Angle X-Ray Scattering (SAXS) and Transmission Electron Microscopy (TEM)... 

Values obtained from small angle neutron scattering (SANS) data for PAMAMs in the same solution as in a for PPIs in D20. 

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