Preparation and characterization of Portland cement pastes with Sm2O3 microparticle additions for neutron shielding applications
| Autor: | Ayodeji Babatunde Alajo, Henry A. Colorado, Raul Florez, Carlos Henry Castano Giraldo |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Cement
Ettringite Materials science 010308 nuclear & particles physics Neutron emission Scanning electron microscope 020209 energy 02 engineering and technology Building and Construction Neutron radiation Microstructure 01 natural sciences law.invention Portland cement chemistry.chemical_compound chemistry law 0103 physical sciences 0202 electrical engineering electronic engineering information engineering General Materials Science Neutron Composite material Civil and Structural Engineering |
| Zdroj: | Construction and Building Materials. 191:498-506 |
| ISSN: | 0950-0618 |
| DOI: | 10.1016/j.conbuildmat.2018.10.019 |
| Popis: | Mechanical, microstructural and neutron attenuation properties of white ordinary Portland cement (WOPC) pastes with Sm2O3 additions ranging from 2.5 to 20 wt% are reported. Scanning electron microscopy (SEM) micrographs revealed that incorporation of Sm2O3 above 10 wt% enhance the formation of ettringite and increase the porosity of the cement composites. Microcracks were also observed in SEM images for compositions containing 20 wt% Sm2O3. X-ray diffraction (XRD) analysis determined that samarium oxide particles did not interact chemically with the cement matrix to form new crystalline phases. On the other hand, neutron transmission experiments and Monte Carlo simulations showed that the attenuation of thermal and epithermal neutrons increased significantly with the addition of Sm2O3. Maximum enhancement in neutron shielding was obtained for specimens loaded with 20 wt% Sm2O3, which have an effective removal cross section of ∑ eff = 4.018 cm - 1 compared to ∑ eff = 0.515 cm - 1 for plain WOPC paste. |
| Databáze: | OpenAIRE |
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