This study investigated effects of different sizes, concentrations, volumes, and surface areas of polymethylmethacrylate (PMMA) particles on human macrophages. Adherent peripheral blood monocytes isolated from five healthy individuals were exposed for 48 h to phagocytosable (0.325 pm and 5.5 pm) and
Dissolution Effects on Specific Surface Area, Particle Size, and Porosity of Pentelic Marble
β Scribed by Malvina G. Orkoula; Petros G. Koutsoukos
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 362 KB
- Volume
- 239
- Category
- Article
- ISSN
- 0021-9797
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β¦ Synopsis
Dissolution of natural stone such as marble is not limited to its surface. The porous structure, known to play an important role in stone decay, is also affected by the conditions of dissolution. In the present work, the changes in pore size distribution of Pentelic marble particles accompanying chemical dissolution in undersaturated solutions and at alkaline pH 8.25 were investigated. The specific surface area and the mesopore distribution of the Pentelic marble tested showed a pronounced decrease to very low values. On the other hand, the sizes of macropores exhibited a tendency to increase with the extent of dissolution due either to dissolution in the interior of the pores or to fusion of small pores into larger. Furthermore, the number of small particles decreased significantly, reaching complete disappearance, depending on the extent of dissolution. At the same time, the relative number of particles of intermediate size increased.
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