将子结构法和双倒易边界元法联合应用于预测具有三维复杂流存在时管道和消声器的四极参数与传递损失，阐述其基本原理与数值过程。

A substructure method and a dual reciprocity boundary element method (DRBEM) are applied to calculate four-pole parameters and transmission loss of ducts and silencers with complex flow.

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而羧基邻位有酚羟基存在时，则配体以双齿形式与钛配位形成二茂钛六元环状化合物。

And if there is a hydroxyl in ortho position of carboxyl, the oxygen of hydroxyl and carboxyl in ligand are bound to ti to form hexatomic cyclic compound.

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