Filtern
Dokumenttyp
Schlagworte
- XPS (3)
- Deponie (2)
- Core-shell (1)
- Core-shell nanoparticles (1)
- Damage (1)
- Demonstrationsanlage (1)
- Dynamical theory (1)
- Electron backscatter diffraction (1)
- Fremdprüfung (1)
- Geogitter (1)
- Geokunststoffe (1)
- Geomembranes (1)
- Geotextilien (1)
- Interlaboratory Study (1)
- Ionic liquid (1)
- Kinematic theory (1)
- Klärschlamm (1)
- Klärschlammasche (1)
- Kunststoffdichtungsbahnen (1)
- LEIS (1)
- Landfill (1)
- Landfill lining (1)
- Metal fluorides (1)
- Nanoparticle coating (1)
- Nanoparticles (1)
- P-Düngemittel (1)
- Phosphor (1)
- Quantitative XPS (1)
- Ressource (1)
- Simulation (1)
- Size (1)
- Sol-gel synthesis (1)
- Synchrotron radiation (1)
- T-SEM (1)
- Thickness (1)
- ToF-SIMS (1)
- Transmission function (1)
- VAMAS (1)
- X-ray photoelectron spectroscopy (1)
- shell thicknss and chemistry (1)
Organisationseinheit der BAM
We report the results of a Versailles Project on Advanced Materials and Standards (VAMAS) interlaboratory study on the measurement of the shell thickness and chemistry of nanoparticle coatings. Peptide-coated gold particles were supplied to laboratories in two forms: a colloidal suspension in pure water and particles dried onto a silicon wafer. Participants prepared and analyzed these samples using either X-ray photoelectron spectroscopy (XPS) or low energy ion scattering (LEIS). Careful data analysis revealed some significant sources of discrepancy, particularly for XPS. Degradation during transportation, storage, or sample preparation resulted in a variability in thickness of 53%. The calculation method chosen by XPS participants contributed a variability of 67%. However, variability of 12% was achieved for the samples deposited using a single method and by choosing photoelectron peaks that were not adversely affected by instrumental transmission effects. The study identified a need for more consistency in instrumental transmission functions and relative sensitivity factors since this contributed a variability of 33%. The results from the LEIS participants were more consistent, with variability of less than 10% in thickness, and this is mostly due to a common method of data analysis. The calculation was performed using a model developed for uniform, flat films, and some participants employed a correction factor to account for the sample geometry, which appears warranted based upon a simulation of LEIS data from one of the participants and comparison to the XPS results.
An approach to achieve 'zero leakage' is discussed with respect to experience in Germany, where strict regulations for landfill lining and capping Systems have been developed and issued because of large environmental Problems related to landfills that accumulated in the 1970s and 1980s. Using a thick, high-quality high-density Polyethylene (HDPE) geomembrane (GM) that is installed free of residual waves and wrinkles in intimate contact with a compacted clay liner or geosynthetic clay liner of very low permeability, by a qualified, experienced, well-equipped and properly third-party-controlled installer, and which is protected by heavy protection layers designed with respect to the long-term performance of the GM may result in a liner or capping system of practically no leakage. This is demonstrated by analysing results of measurements obtained from permanently installed leak-detection Systems in combination with HDPE GMs. The survey was based on 32 German landfills with 1.276.500 m² of installed GMs.