Based on a rational analysis of magnitude orders, the authors have obtained simplified equation systems at two levels, from which the fundamental pattern of the flow and its revision have been deduced smoothly; the damp effect of the vertical component of the magnetic field has been reasoned logically and the cause of the metal surface bump has been shown clearly.

This paper presents a basic law of the simplified equation of surface of degree 2, especially the law of the simplified equation of surface of degree 2 with two equal zero roots.

GFRs were estimated by abbreviated MDRD equation and the modified MDRD equation separately.

A linear simplified equation for titration of alkali with hydrochloric acid is presented and applied to determine dilution solution of very weak alkali, mixture of strong and very weak base, polyprotic alkali , and medicinal sodium bicarbonate .