[Retracted] Composite Nano-Calcium-Based Material for Reinforcement and Protection of Earthen Ruins in Humid Environment

Table 1

Surface hardness of the sample.

Density (g cm^−3)	a-solid content (%)	Hardness (HL)
		3 d	7 d	14 d	21 d	28 d
1.55	0	208	213	216	216	217
	0.2	206	212	219	221	223
	0.4	214	219	222	226	225
1.65	0	196	217	218	221	220
	0.2	215	207	215	224	225
	0.4	212	221	225	227	229
1.75	0	190	223	228	230	231
	0.2	189	212	234	240	242
	0.4	208	231	242	246	249