Aiming at heavy duty and low speed gear transmission, Zheng Zhou Research Institute of Mechanical Engineering puts forwards ZY-1 case- hardened double-circular-arc gear.

为此，郑州机械研究所针对低速重载齿轮传动领域设计了ZY-1型硬齿面双圆弧齿轮齿形。

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Objective:To study the growing law of Sarcophaga carnaria in early autumn in Zheng zhou City in order to find out the more exact data for the estimation of the postmortem interval for this region.

目的：探讨郑州地区初秋季节嗜尸性麻蝇的生长发育规律，为该地区该季节人体死亡时间推断提供法医昆虫学较确切数据。

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The first nobility to help the Zhou kings was the Duke Zhuang of Zheng (r. 743 BC-701 BC).

第一贵族帮助周国王是杜克大学的郑庄（河743公元前701年） 。

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