To establish an up-to-date and world-classevaluation system by 2035, an overallplan on educational evaluation reformwas issued on October 13, which proposes afo
With the National Day holiday in October showing a remarkable surge in domestic travels, a sign of the revival of the tourism industry, Zhao Xia is looking forw
Educational systems vary from countryto country and culture to culture; theeducational means with which we teachthe next generation have arguably one of thegrea
The county of Zuoquan in Shanxi Province in north China has gone through two transformations in the recent century. Originally called Liaoxian, its name was cha
2009年12月，哥本哈根联合国气候变化大会的举行再一次向世人宣布了全球变暖等环境问题的严重性。随着人类社会的进步和工业文明的迅速发展，工业排放已经对全球环境造成破坏性的
质子交换膜燃料电池目前普遍使用全氟磺酸膜,膜的水含量直接影响质子在膜中的传导和膜的机械强度,并进一步影响电池性能,因此保持膜的适度湿润性非常重要。通常采用各种增湿方法来对反应气进行增湿,但这会增加系统的复杂性以及体积和重量,为了简化系统,提高系统的体积比功率和质量比功率,近年来,出现了很多从电池材料和结构入手进行优化设计的自增湿方法,但效果都不是很理想,也还没有完全实用化。本文从实现燃料电池自增湿
The Golden Valley is a dazzling 48-km belt in Zuoquan County in Shanxi Province, north China, named so after its variety of trees with bright yellow leaves that