排序方式: 共有7条查询结果,搜索用时 15 毫秒
1
1.
根据吉林双沟水电站混凝土面板堆石坝区的水文气象和工程地质资料,分析和确定坝体初期渗水流量及水位上升速度,依此制定坝体反向排水系统封堵时间、顺序和方法。 相似文献
2.
3.
4.
15%Ag-added cubic perovskites Sr0.9La0.1TiO3 and Ruddlesden-Popper (RP) phases Sr2.7La0.3Ti2O7 were fabricated via hydrothermal synthesis, cold pressing and high-temperature sintering. The structure and thermoelectric properties were also investi-gated for all samples. The results indicated that Ag precipitated as a second phase. Ag addition made electrical conductivity and ab-solute Seebeck coefficient enhanced, as a result, the ZT values were enhanced both for two series. Compared with cubic perovskite, RP phase was subjected to smaller impact by Ag addition. The reasons for enhancing ZT value and the different impact for two series by Ag addition were also discussed. 相似文献
5.
圆形断面均匀流水深计算需完成隐含的高次三角函数求解,无法完成直接获解。为解决传统算法及近似算法存在的计算过程繁复或精度不高等问题,通过对其均匀流水深求解方程进行数学变换,采用优化拟合的方法,以标准剩余差最小为目标函数,经拟合获得了计算较为简捷、成果最大相对误差小于0.44%的近似公式,具有一定的实用推广意义。 相似文献
6.
7.
1