In this paper, mechanical model of traditional bellow type pressure compensator is established. The analysis of static characteristic shows that compensation volume and variation of pressure compensate margin are limited to each other. As a result, it cannot meet the requirements of marine equipment to the underwater hydraulic power. Therefore, a new type of pressure compensation unit is developed, it has advantages of big volume compensation and almost constant pressure compensate margin, it solves the core technical problem of deep-water balancing hydraulic power. The simulation results show that this new type of pressure compensator can satisfy the design requirements and improve the working depth of underwater hydraulic systems sharply.

Nanoscience and nanotechnology have advanced in recent years followed by groundbreaking discoveries that allow a remarkable control of molecular entities in the nanoscale. Advances in the field still came in many cases without a detailed and profound understanding on the effects and impact that nanotechnology and nanomaterials can have in our future society. In this work, we have aimed to provide a short but relevant overview on the impact and risks of nanotechnogy and the possibilities to engineer safer nanomaterials for a controllable working environment.