2019冠状病毒疾病（Coronavirus Disease 2019）...

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催化剂的酸度与丁烯-1异构化活性呈线性关系.The relationship between acid amount of the catalysts and activity of the isomerization of 1 - betene was linear....

6月份的出口额上升了1.5%，创下309.1亿美元的历史最高纪录。Exports in June rose 1.5% to a record $30.91 billion.1978年有884名学生，师生比为1比15。In 1978 there were 884 students at a lecturer/student ratio of 1:15.今年，工厂生产的小轿车可能只有1,500辆。The factory may make a...

“丁烯-1”的英语可以翻译为：utene-1，a-butalene，ethylethylene ...