On the down stroke of the pump the outer and inner rings provide a fluid passage and on the upstroke they play the role of sealing .

两活塞环在下冲程时提供进液通道，上 冲程 时起密封作用。

During the course of the upstroke the membrane potential attains zero and an electrical gradient no longer exists .

在 升 支 发展过程中，膜电位一达到零，电位梯度即不再存在。

The incidence of malignant arrhythmia in patients with unidirectional curve and in those with convex shape of ST - segment elevation was apparently increased as compared with the patients with smooth upstroke slope shape ( P < 0.05 ) .

观察组单向曲线及 弓背 向 上型ST改变病例与 上斜型病例比较，其恶性心律失常明显增多（P<0.05）。

Be sure to ventilate on the upstroke .

要明确 吹气是在 手 抬起 时 吹入的。

Neither sodium valproate nor Verapamil showed any effect on action potential amplitude overshoot resting potential and phase O upstroke velocity .

丙戊酸钠和异搏定对动作电位幅度、超射值、静息电位、O期 最大 除 极速度均无明显影响。

So when a bird banks right its left wing moves faster on the downstroke while the right is faster on the upstroke which slows the animal 's rotation .

因此，当鸟儿向右侧倾斜飞行时候，它的左翼向下拍打的速度要比右翼向 上 拍打的速度快一些，这样就可以使旋转减速。

The thrust force is mainly due to the drag of the wings in the upstroke .

平衡 身体阻力的推力主要由翅膀 上拍 中 产生的阻力 提供。

The power loss in barrel-plunger pair occurring on the upstroke of a subsurface pump is comprised of leakage loss and friction loss .

抽油泵上行程提液 时 柱塞副功率损失包括漏失损失和摩擦损失。

Passenger Transport Special Line Upstroke Type 900T Cased Beam Mobile Model Carrier Bridge-building Machine and Construction Technology

客运专线 上 行式900吨箱梁移动模架造桥机及施工工艺

There are three stages for each plunger lift cycle : upstroke after flow and buildup .

将柱塞举升的单个周期分为三个阶段： 柱塞 上行阶段、续流阶段和 关 井 压力，恢复阶段，建立了柱塞举升 系统 模型。

Therefore a new algorithm of geometrical Pareto evolution algorithm with complex ( GPEC ) based on geometrical characters is used to make a multi-objective optimal design for maximum torque factor and polished rod acceleration on the upstroke of a conventional pumping unit .

为此，采用一种新的集复合形方法和几何选择为一体的多目标Pareto进化算法（ GPEC），对常规型抽油机的 上 冲程最大扭矩因数和上 冲程悬点加速度进行多目标优化设计。