In order to acquire the surface wind fields of the urban area over the complex terrain,three-dimensional wind fields were analyzed with mass consistent model for wind fields(MCF) based on the historical data from isolated observation stations.

A one-dimension flux model for the secondary settling tank based on the mass conservation;

Based on the mass conservation law,this paper introduces a simple and feasible method for measuring hydrogen and oxygen stable isotopic concentration in soil water,which can avoid directly extracting soil water.

A tracer dilution physical model of measuring seepage velocity was reestablished according to tracer mass conservation,and a new formula of calculating the horizontal seepage velocity was given by infinitesimal method which modified the generalized dilution formula.

But the trace quality conservation is used to solve the problem.

This paper infers, from the law of fine equilibrium and the law of conservation of mass, the relationship between rate constant of primary reaction and chemical equilibrium constant of general reaction and the relationship between primary reaction and general reaction.

In a steady finite length channel of gas flow,analytical expressions of the pressure distribution along the channel axis and of mass flow rate are obtained by the global mass conservation law for continuum and slip flow regimes.