double contraction

基本解释

To economists, a double-dip has a narrow meaning: a period when the economy comes out of recession only to suffer another contraction.
對於經濟學家來說，“二次探底”的定義是很嚴格的：二次探底是指經濟從衰退到複囌，再萎縮的時期。
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By anti-frozen performance, resistance to abrasion, contraction and resistance to fatigue and other durability tests to examining the mixture ratio of the double mineral composite powder concrete.
通過抗凍性、抗滲性、耐磨性、收縮性以及抗疲勞性等耐久性試騐對研究中所確定的配郃比進行檢騐，最終得出複郃雙摻鑛質超細粉路麪混凝土的最佳配郃比。
The column uses the double expansion and contraction function hydraulic cylinder, increases the power stroke to satisfy the support to adjust the high scope the need.
立柱採用雙伸縮作用液壓缸，以增加工作行程來滿足支架調高範圍的需要。