Surface/subsurface processing damage on optical component can severely affect its surface mechanical properties and cause its resistance to external deformation to deteriorate. At the same time, the processing damage will also affect the surface quality. The surface processing defects are the main reasons leading to the decrease in the laser induced damage threshold in high-density laser system. In this paper, the damage formation mode and morphology of the traditional optical processing methods based on the mechanical removal in brittle and plastic modes are evaluated, then the traditional processing damage model is established accordingly. The polishing technology with material removal in elastic mode is proposed based on the damage generation mechanism. In the elastic mode, it is impossible to form the material removal by mechanical action due to the inability to overcome the yield limit of the material, thus it is necessary to introduce a weakening of the chemical reaction to reduce the bonding force of the surface layer of the optical element, using less force to form the material removal to ensure the disturbance of the basic material is controlled. The mechanism of material removal in elastic mode was analyzed. The polishing process was realized by elastic hydrodynamic ultra-smooth polishing and nano-particle jet polishing. The performance of the elastic polishing process was analyzed. The experimental results show that the elastic polishing processing method can effectively remove surface damage and achieve effective control of processing damage.

Alumina is the most promising ceramic armor material and SHPB testing is typically used to investigate dynamic deformation behaviour and ballistic mechanisms. In this research the effect of the incident wave shaping technique on the stress equilibrium state during testing was analysed. The compressive strength of alumina ceramic materials was evaluated under high strain rate compressive loads of 1200-1800/s. The SHPB compression strength was found to increase with decreasing grain size to a maximum of 3.80±0.25 GPa, and the ceramic materials studied exhibited high strain-rate sensitive mechanical properties due to crack tip inertia effects.

The natural characteristics with dense water network and co-existent land and water determine the leading role of water network in natural ecological environment of this region. But with the development of economy, construction land for small towns in water-network region in Southern Area of Yangtze River is increasing obviously and ecological environmental problem is becoming prominent gradually. Research on strategies to guide healthy development of small towns’ space from the layer of their spatial pattern can solve the contradiction between spatial development of water-network small towns and space Protection of natural ecology and regulate the reasonable expansion of natural ecological environment and town space in water-network region.

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Water network play an important role in the natural and human environment, green network is basis for achieving ecology; town is main focus of environment which is hot research issue. Systematic layout of the water network, green and urban space is core contents for ecology planning in water networks. The article research ecology through water networks and green, therefore, distribution problem such as water, green land and construction land could be solved properly; we can achieve comprehensive development on the premise of ecological function, thus, human and natural's networks and ecological combination can be achieved at the same time.