叙述了滚动球窝喷管在设计中许用接触应力的选择依据及方法，并根据以往的经验公式及其试验数据对影响许用接触应力的几个因素进行了分析。
Selection basis and method on allowable contact stress of rolling ball-socket nozzle were described. Based on empirical formula and test data, several factors affecting allowable stress were analyzed.
山西省阳高县许家窑出土了大量的石球。
A large number of stone balls were unearthed in Xujiayao, Yanggao County, Shanxi Province.
他们已经打进5球，但也丢了6个。教练许丁茂承认后防是个问题，乌拉圭目前还保持大门不失。
They have scored five goals to date, but conceded six, and their coach, Huh Jung-moo, admits that defence is a concern, with Uruguay yet to concede in the tournament.
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