One kind of hydroxyl - terminated aliphatic polycarbonate, i. e. poly(ethylene ether carbonate) diol(PEECD) was synthesized and used to toughen epoxy resin (EP) .

合成了以羟基封端的脂肪族聚碳酸酯-聚乙基醚碳酸酯二醇（PEECD），并用于环氧（EP）树脂的增韧。

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Thirty states now require some form of ID at the polls, and one goal of Mr. Holder's attack is to intimidate other states that want to toughen their laws.

WSJ: Review & Outlook: Holder's Voter ID Fraud