There are some equilibriumof sodium hydroxide and ca rb onate in primary brine,so in determinting of contents of sodium hydroxide and c arbonate,this contents must be calculated and distinguished according to actiua l equilibrium.

Aiming at unbalanced and stagnant growth of small businesses, we find out the nature and equilibrium relations of small businesses growth and put forward the tactics how to obtain and sustain solid grow.

The target of engineering construction can be classified in quality, process and investment, the three targets influence and restrict each other, the relation of them can be concluded with substitution relation and balance relation.

Improvement on energy saving effect of a compound balance beam pumping unit with downward beam balance weight;

Conventional beam pumping unit energy saving reconstruction based on structure optimization and compound balance;