Although , a lot of works have been done on the fruit damage by means of experiment methods . the primary goal of the dissertation is to study how the applied forces transfer and distribute inside plant tissues in the cell level , and the relationship between the external force and turgor , as well as the stress of the cell wall 本文主要研究宏观的外力如何传递到细胞中去的和外力的刺激是如何在细胞间分布和传递，即外力与细胞层次受力的关系，尝试从细胞受力的角度分析水果机械损伤的机理等问题。
When pump is applied force downward and moves , the lower check valve is closed , the fluid in the pump is extruded and charges upward out of upper check valve , then flows into upper pump chamber , because that the piston has volume , some fluid flow out of outlet due to the reduce of spatial fluid volume in upper pump chamber 当泵的柱塞受力向下移动时，下止回阀关闭，泵中的液体受挤压而向上冲开上止回阀而流入上泵室中，由于柱塞本身占有体积，部分的流体因上泵室内空间流体积的减少而自出口端流出。
Air piston pump adopts the theory that " pressure " applying force on various areas and can produce various " acting force " , the pump takes the origin that the compressed air is compressed energy , and transforms the pressure of compressed air into more fluid pressure , pressing fluid move in order to achieve the aim of high viscosity and ultra - viscosity fluid 气动柱塞泵是利用“压力”在不同的面积上施力，产生不同“作用压力”的原理，以压缩空气为压力能量的来源，将压缩空气的压力转换成更大的流体压力，压迫流体移动，进而达到输送高黏度及超高黏度流体的目的。
