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The determination of cement and sand content in an aged cement mortar is a challenging problem for civil engineers. Techniques like x‐ray diffraction (XRD), thermogravimetric analysis (TGA) and electrochemical impedance spectroscopy (EIS) are well established, which can give some insight of the hydrated products. The present study is an attempt to use x‐ray photoelectron spectroscopy (XPS) technique for the evaluation of ordinary Portland cement (OPC), sand (aggregate) composition and carbonation study in hardened cement mortar. Carbonation analysis and cement to sand ratio for all mortar compositions has been determined and studied in detail in the present work. The C 1s spectra of cement mortar with ratios 1:1, 1:3 and 1:6 shows carbonate formation on the surface with 21, 40 and 32 atomic percent, respectively. An increase in SiO2 content corresponding to sand is observed for all three mortar mix. The formation of silica gel due to carbonation has not been observed in the mortar samples. The cement to sand ratio for all three mortar mixes is found to be in 20–30 percent error limit due to the heterogeneous nature of the mortar system.

Summary In the present work, microencapsulated phase change material (M‐PCM) has been synthesized with eutectic mixture (75% SA + 25% CA) as core and melamine formaldehyde (MF) as shell using in situ polymerization. Advanced instrumental techniques like field emission scanning electron microscopy (FE‐SEM), Fourier‐transform infrared spectroscopy (FT‐IR), particle size analyzer (PSA), thermogravimetric/differential thermal analysis (TG/DTA), differential scanning calorimetry (DSC), and thermal conductivity analyzer (TCi) were used to characterize the synthesized M‐PCM, and impact of effective parameters like pH and agitator speed on the encapsulation process was also elucidated. Results obtained reveal that at the optimized pH (3.2) and agitator speed (1500 rpm) M‐PCM possess smooth surface morphology, spherical in shape with particle size of 10.41 μm. Based on FT‐IR analysis, it was observed that the synthesized M‐PCM was uniformly encapsulated by MF resin with eutectic mixture in the core. The encapsulation process results in the improvement of the thermal stability of eutectic mixture, it increases from 202.5 to 212.3°C, and the encapsulation efficiency of the M‐PCM is found to be 85.3%. The melting point and latent heat of fusion of M‐PCM were found to be 34.5°C and 103.9 kJ/kg, respectively.

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