Natural hydraulic lime (NHL) is a promising grouting material for stone heritage conservation, but is limited by low strength and high brittleness. 2-acrylamide-2-methylpropanesulfonic acid (AMPS) water-absorbing resin was used to modify NHL through one-step in situ polymerization, and the obtained AMPS/NHL composite material was characterized by XRD, FT-IR and SEM. Isothermal calorimeter was adopted to monitor the hydration heat releases of NHL before and after AMPS water-absorbing resin modification. The mechanical properties (flexural, compressive and bonding strength) of the cured slurry were tested using a universal testing machine. The results indicate that the acicular network structure generated by AMPS in NHL slurry can strengthen the internal connection of the slurry, improve the bonding effect, and significantly enhance the mechanical properties of the slurry. After curing for 28 days, the compressive strength of 3% AMPS modified slurry increased by 60.7 % to 5.37 MPa, with increase of 12.8 % and 32.5 % in bonding and bending strength, respectively.

In this work, a series of Zn_xMg_1.99-xSnO₄:0.01Mn²⁺ (x = 0, 0.01, 0.02, 0.03, 0.04) green long afterglow phosphors are prepared by high-temperature solid-phase reaction. The photoluminescence and long afterglow performance of host material doped with Zn²⁺ are investigated. The results show that the emission peak of Mn²⁺ is red-shifted by 5 nm with increasing Zn²⁺ concentration. Zn_0.03Mg_1.96SnO₄:0.01Mn²⁺ phosphor has the strongest green luminescence intensity with the chromaticity coordinates of (0.0857, 0.6083) under 270 nm, and Zn_0.01Mg_1.98SnO₄:0.01Mn²⁺ phosphor has superior long afterglow performance with average lifetime of 102.41s. The afterglow decay and thermoluminescence curve of phosphor are used to explain the mechanism of long afterglow luminescence. Meanwhile, the afterglow intensity distribution of each pixel in Zn_0.01Mg_1.98SnO₄:0.01Mn²⁺ coating samples is carried out by hyperspectral imaging, and the optimal luminescence intensity and uniformity of the sample are obtained at a phosphor/epoxy mass ratio of 0.0025. Therefore, Zn_0.01Mg_1.98SnO₄:0.01Mn²⁺ can be a potential candidate of novel long afterglow phosphors, and hyperspectral imaging also provides new research approaches for the rational proportioning of luminescent materials.