0000000000240108

AUTHOR

Helmut Rauch

showing 3 related works from this author

Structural investigation of hybrid nanocomposites

2002

Ultra small (USANS) and small angle neutron scattering (SANS) techniques were employed to study an elastomer styrene–butadiene, where two kinds of silica fillers have been added in different amounts. Small silica-particle fillers are expected to modify morphological and mechanical properties when dispersed in the copolymer matrix. The USANS and SANS techniques can span a wide range of momentum transfer, investigating morphological properties of the filled elastomer over a number of decades in length scale. Surface and mass fractal behavior has been observed over different length scales.

Length scaleMaterials scienceNanocompositeMomentum transferGeneral ChemistryElastomerSmall-angle neutron scatteringMatrix (geology)Condensed Matter::Soft Condensed MatterCondensed Matter::Materials ScienceFractalCopolymerGeneral Materials ScienceComposite materialApplied Physics A: Materials Science & Processing
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Scattering studies of large scale structures at the ultra small angle neutron scattering instrument S18

2002

Abstract In recent years ultra small angle neutron scattering (USANS) has developed into a powerful standard method for large scale structure investigations. The upgraded instrument S18 at the ILL's 58 MW high flux reactor is operated routinely with increasing beam time demand. The performance of the instrument and its abilities will be discussed in this paper. A peak to background ratio better than 10 5 is reached using Agamalian's tail reduction method. A q -range from 2.10 −5 up to 5.10 −2 A −1 can be covered. This allows a clear overlap with standard pinhole SANS instruments. The new way collecting scattering data logarithmically equidistant in q -space saves measuring time. This allows…

Statistics and ProbabilityRange (particle radiation)Materials scienceScatteringbusiness.industryCondensed Matter PhysicsSmall-angle neutron scatteringOpticsFractalPinhole (optics)EquidistantSoft matterbusinessBeam (structure)Physica A: Statistical Mechanics and its Applications
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Measurement of the Coherent Neutron Scattering Length of (3) He.

2005

By means of neutron interferometry the s-wave neutron scattering length of the (3)He nucleus was re-measured at the Institut Laue-Langevin (ILL). Using a skew symmetrical perfect crystal Si-interferometer and a linear twin chamber cell, false phase shifts due to sample misalignment were reduced to a negligible level. Simulation calculations suggest an asymmetrically alternating measuring sequence in order to compensate for systematic errors caused by thermal phase drifts. There is evidence in the experiment's data that this procedure is indeed effective. The neutron refractive index in terms of Sears' exact expression for the scattering amplitude has been analyzed in order to evaluate the m…

Physicsbusiness.industryGeneral EngineeringPhase (waves)Neutron scatteringelastic neutron scatteringneutron interferometryproperties of the 3He nucleusArticleComputational physicsScattering amplitudeInterferometryOpticsPerfect crystalNISTNeutronreal part of the coherent scattering lengthbusinessRefractive indexfew body systemsJournal of research of the National Institute of Standards and Technology
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