Two sets of analytical solutions of 1-d unsteady isentropic perfect gas flow with area change are given.

本文给出了两组一元变截面不定常可压缩完全气体等熵流的解析解。

At higher temperatures the equation of state becomes better and better approximated by the "perfect gas" law.

在更高的温度区内，状态方程越来越接近于“理想气体”定律。

The "first-time smartphone buyer" is a bit of a mythical creature, like a perfect gas in physics, or a unicorn or jackalope.

“首次购买智能机的用户”是一个有点神秘的东西，就像物理学中的理想气体、或是一头独角兽或鹿角兔。

The pressure in a perfect gas, being directly proportional to the kinetic energy of the molecules, has a lower bound of zero.

理想气体的压力与分子的动能成正比，它的下限为零。

The state function, entropy, is introduced by the means of a perfect gas behavior, and the second law of thermodynamics is demonstrated based on the first law.

本文以理想气体的行为为手段引出熵函数，并以热力学第一定律为基础，论证了熵增大原理。