New theory in the front of theoretical basis research of molecular thermodynamics 4: on molecular structure of organic compound and theoretical equation of critical pressure;

Prediction of the critical pressures of alkanes using a quantitative structure property relationship;

The critical pressure of two spans beams with one end fixed and the other hinge joined;

The curvature formula of tiny curved rod,together with the vector method of area,is applied to inference for Euler formula about critical load of slender compressive rod which one end is fixed and another is free.

And then,the equations are applied to inference for Euler formula about critical load of slender compressive rod with common constraints.

In elastic mechanics, it is common practice to calculate critical loads in buckle of thin plates by means of double triangle series.

From the ample computational results,the relationships among maximum entrainment ratio,expansion ratio and critical compression ratio were concluded.

Two compound parameters, expansion ration and critical compression ratio, are introduced to conc.