【摘 要】
：
ICA National Atlas Commission held a commission meeting and symposium from August 8-12,1990 in Beijing.Among those present at the meeting were Dr.B.Rystedt(Swed
论文部分内容阅读
ICA National Atlas Commission held a commission meeting and symposium from August 8-12,1990 in Beijing.Among those present at the meeting were Dr.B.Rystedt(Sweden),Chairman of ICA,Dr.E.Ciekirska(Canada),Vice Chairman of ICA and members from U.S.A.,China,S
其他文献
复频筛是一种新型高效的筛分设备，具有电磁振动、高频率、设备处理能力大、筛分效率高等优点。工业试验表明，利用该设备代替原高频振动尼龙细筛，可及时筛出合格细粒级。大大提高
模具压力中心的确定是冲裁加工的关键问题,其计算求解一直都比较困难.巧妙地利用了三维机械设计软件SolidWorks中的重心和面心特性与压力中心相联系,从而实现高效、准确的压
TheThe Regional Conference on Asian Pacific Countries of the IGU was held from August 13 to 19,1990 at Beijing,on the premises of Peking University.It was the first of such event of the Union to take
上海实业交通电器有限公司(以下简称"上实交通")是上汽集团电子电器系统的核心企业,生产20大类汽车电机、电器、电子电器产品,已达到200多种品种,上海大众、一汽大众、北京吉
Since 1960 research in the geography of enterprise hasexpanded dramatically. This review gives a critical analysis of the geography of enterprise around five main facets. Firstly, it briefs five appro
针对多绳摩擦提升机运行中典型的过卷和打滑故障，根据矿井提升实际运行情况，重点分析了爹绳摩擦提升机制动器工作参数及其对提升机过卷与打滑故障的影响，提出了多绳摩擦提升机过
介绍了采煤机液压制动器的工作原理、结构特点,并对乳化液介质液压制动器研制过程中的关键部件油缸、活塞的防锈和密封措施以及制动器设计的一些创新点进行了详细说明,乳化液
针对国产新型S135掘进机对薄煤层的适应性，详细介绍了该掘进机的主要技术特征、总体结构特点、系列化、发展趋势及使用效果，可供掘进机设计和选型作为参考。