The researchers explored how to make a high mass fraction coal-water slurry using coal from Chongqing. They tested different additives, amounts, and pH levels to see how well the slurry performed. They found that one additive, naphthalene additive A, worked best with Chongqing coal, giving the highest slurry mass fraction and best fluidity. The optimal conditions for this additive were a mass fraction of 0.35%, a pH value of 8-9, and a specific ratio of coal particle sizes.