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In this work, the phase equilibrium solubility of 5-fluorocytosine (5-FC) in dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), 1-butanol, acetonitrile, 1-propanol, 1,4-dioxane, acetone, ethyl acetate, 2-propanol, 2-butanone, and mixture systems (DMSO + 2-propanol and DMF + 2-propanol) at a series of temperatures (283.15–323.15 K) is determined, and model correlation, solvent effect, and preferential solvation analysis are researched. The solubility of 5-FC is related to temperature, which decreases with decreasing temperature. For monosolvent systems, the mole solubility order is DMSO > DMF > 1-butanol > 1-propanol > 2-propanol > acetone > 2-butanone > 1,4-dioxane > acetonitrile > ethyl acetate. The solvent effect has been studied in monosolvents, hydrogen-bonding acceptor (HBA) interactions and nonspecific dipolarity/polarizability interactions favor dissolution, and solvent self-cohesiveness is not beneficial to dissolution. For two mixture systems, the mole solubility of 5-FC in DMSO + 2-propanol solvent systems is higher than that in DMF + 2-propanol solvent systems. A dimensionless parameter (δ) is defined to observe the deviation from ideality of mixed solvents whose values are all greater than zero. The equilibrium constant of the solvent exchange process (K ps) can be used to evaluate the preferential solvation of 5-FC. DMSO or DMF dissolves 5-FC in the local region around 5-FC preferentially. The equilibrium solubility data is correlated by four correlation models (modified Apelblat, λh, CNIBS/R-K, and Jouyban–Acree models). The greatest relative average deviation (RAD) and root-mean-square deviation (RMSD) values are 2.01% and 11.87 × 10–5 in pure solvent systems and 2.20% and 5.99 × 10–5 in mixture systems, respectively. These four models show excellent correlation with the experimental solubility data.

Sodium bicarbonate blasting was applied to remove the corrosion layer of ancient bronze artifacts. Scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) was employed to investigate the surface morphology, and element composition of the bronze coin surface before and after blasting. X-ray diffraction (XRD) was used to characterize the mineralogical composition of products in the corrosion layer of the bronze coin. The products are cerussite (PbCO3), lead oxide (PbO2), cassiterite (SnO2), bobkingite Cu2Cl2(OH)8(H2O)12 and malachite Cu2(CO3)(OH)2 which can be effectively removed by employing an impinge angle of 90°, working pressure at 0.3 MPa. These results indicate that sodium bicarbonate blasting can achieve non-destructive removal of the corrosion layer on the bronze coin. This work will be helpful for better restoration and preservation of the bronze cultural relics.

Pumped Storage Hydroelectricity (PSH) is a very important method for energy storage. The cycle of water usage, starting with using excess energy, is of great significance for saving energy and improving social and economic benefits. This paper focuses on the analysis and prediction for the ten years' development potential of PSH in China. By analyzing the basic principles and computation methods to understand how PSH works. There are introductions and explanations of two huge PSH projects to determine the current advantages and suggest improvements. Based on China's current national conditions and geographical regions, PSH is suitable and being promoted to be developed, and it will help the country reach the objective of carbon peaking by 2030 and carbon neutrality by 2060. By comparing PSH to its potential competitor, Solid Gravity Energy Storage (SGES), the advantages of maturity and applicability of PSH in China allows PSH to be developed better. Therefore, the thesis evaluated the PSH's future development and concluded that this technology should be promoted in the future.