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Advanced Construction Materials and Technologies
ab
The changes of absorbance caused by change of reflection angle of infrared ray [1]:
1. The cavity effect. The effect of cavities depends on the quality of polishing the surface of the natural stone (surface roughness). If the IR ray enters to cavity, the absorption increases. The cavities are filled, using chemical impregnation agents with the absorption decreasing.
2. Volume scattering. The
scattering is caused by the cd passage of IR ray through a
Figure 1.The changes in the spectrum of absorption of samples of Bukivskyi gabbro (Galant) between mechanical and chemical treatment: a – Impregnation agent 1 (pH = 5.36); b – Impregnation agent 2 (pH = 3.98); c – Impregnation agent 3 (pH = 9.12); d – Impregnation agent 4 (pH = 7.45)
According to fig. 2, the largest change in absorption of gabbro within the wavelengths of 1111 ¬ 387 is observed for Impregnation agent 1 and 2. After Impregnation agent 3 and 4 treatment the changes of absorbance is not significant.
Main conclusions are:
1. The essence of chemical processing is the penetration of the means in the pores, microcracks and cavities of the stone and subsequent crystallization in them and the formation of the film, which is confirmed by infrared spectral analysis.
transparent layer of chemical impregnation agents and a change in the angle of reflection.
Figure 2.The reduction of absorbance of Bukivskyi gabbro (Galant) according to chemical treatment
2. The change in the absorption of infrared radiation is due to the effect of cavities and the scattering of rays in connection with the transition, through a crystallized film, of chemical impregnation agents
4. Acknowledgment
Authors thank the European Regional Development Funds program (EU-FEDER) and the MINECO (project MAT2016-79866-R) for financial support.
5. References
Rost E., Hecker C., Schodlok M., van der Meer, F. (2018), Rock Sample Surface Preparation Influences Thermal Infrared Spectra, Minerals, 8(11), 475, 21 p.
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