Based on the perturbation theory, the Perturbed Square Well chain Equation of State (PSWC EOS) for chain like liquid system has been developed.

基于微扰理论及方阱流体配位数模型，建立了适用于链状流体的微扰方阱硬球链状态方程。

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Whitmire notes that Sedna, thought by some to be an inner Oort Cloud object, may have also been perturbed by Tyche, since Sedna has an orbit well beyond that of Neptune.

FORBES: Sun May Still Have Low-Mass Solar Companion, Say Astrophysicists Searching NASA WISE Mission Data