Soil should also be tested for its pH level, a measure of the acid and alkaline balance.

VOA: special.2009.06.09

If I then put it back into its original condition, lower the heat say, temperature back to body temperature and reduce the pH down to seven again, the molecules will re-nature.

假如我把烧杯的温度恢复到初始状态,降低温度,温度降低到体温,将pH值降低到七,这些分子会复性

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