1. |
|
|
2. |
|
|
3. |
|
|
4. |
- Praena, J., et al.
(author)
-
Preparation and characterization of 33S samples for 33S(n,alpha)30Si cross-section measurements at the n_TOF facility at CERN
- 2018
-
In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 890, s. 142-147
-
Journal article (peer-reviewed)abstract
- Thin 33S samples for the study of the 33S(n,alpha)30Si cross-section at the n_TOF facility at CERN were made by thermal evaporation of 33S powder onto a dedicated substrate made of kapton covered with thin layers of copper, chromium and titanium. This method has provided for the first time bare sulfur samples a few centimeters in diameter. The samples have shown an excellent adherence with no mass loss after few years and no sublimation in vacuum at room temperature. The determination of the mass thickness of 33S has been performed by means of Rutherford backscattering spectrometry. The samples have been successfully tested under neutron irradiation.
|
|
5. |
- Theis-Broehl, Katharina, et al.
(author)
-
Self assembly of magnetic nanoparticles at silicon surfaces
- 2015
-
In: Soft Matter. - : Royal Society of Chemistry (RSC). - 1744-683X .- 1744-6848. ; 11:23, s. 4695-4704
-
Journal article (peer-reviewed)abstract
- Neutron reflectometry was used to study the assembly of magnetite nanoparticles in a water-based ferrofluid close to a silicon surface. Under three conditions, static, under shear and with a magnetic field, the depth profile is extracted. The particles have an average diameter of 11 nm and a volume density of 5% in a D2O-H2O mixture. They are surrounded by a 4 nm thick bilayer of carboxylic acid for steric repulsion. The reflectivity data were fitted to a model using a least square routine based on the Parratt formalism. From the scattering length density depth profiles the following behavior is concluded: the fits indicate that excess carboxylic acid covers the silicon surface and almost eliminates the water in the densely packed wetting layer that forms close to the silicon surface. Under constant shear the wetting layer persists but a depletion layer forms between the wetting layer and the moving ferrofluid. Once the flow is stopped, the wetting layer becomes more pronounced with dense packing and is accompanied by a looser packed second layer. In the case of an applied magnetic field the prolate particles experience a torque and align with their long axes along the silicon surface which leads to a higher particle density.
|
|
6. |
- Wolff, Max, et al.
(author)
-
Nuclear Spin Incoherent Neutron Scattering from Quantum Well Resonators
- 2019
-
In: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 123:1
-
Journal article (peer-reviewed)abstract
- We report the detection and quantification of nuclear spin incoherent scattering from hydrogen occupying interstitial sites in a thin film of vanadium. The neutron wave field is enhanced in a quantum resonator with magnetically switchable boundaries. Our results provide a pathway for the study of dynamics at surfaces and in ultrathin films using inelastic and/or quasielastic neutron scattering methods.
|
|