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By taking the National Ignition Facility(NIF) from the USA and the Laser Megajoule(LMJ) from the France for examples,this paper analyzes the general layout and general structure engineering features of Inertial Confinement Fusion(ICF) laser facility.NIF is designed with a U-shaped building layout,and it not only can provide an optimum laser experimental equipment configuration but also allow the equipment to attach a second target chamber in future.The bundles of LMJ are arranged in an in-line building.Its layout decreases the optical path-length between the output of each beamline and the focusing system also provides an option for a second target chamber exists.The paper suggests that the general layout of an ICF laser facility should meet the requirements of the physical experimental purposes and should be characterized by operation stability,good integration and higher maintainability.Furthermore,it should design convenient interfaces for future development.In overall design of the equipment,optical elements are packaged into a optical-mehanical assemblies,and replaceable units(LRUs) are assembled with kinematic mounts.The general structure of ICF design should match the arrangement of the laser beams in structural layout and configuration.Moreover,the structure design can not dispense with the function,stability and cleanliness.The assignments of general structure design should meet the requirements of the installation and localization,integration and debugging,operation and maintenance of the optical components and the physical/optical diagnostic equipment.

The interaction of an anti-cancer drug camptothecin with salmon sperm DNA was studied by spectroscopic techniques.DNA induced slight hypochromic and bathochromic effects on the UV-Vis absorption spectra of camptothecin,but strong fluorescence quenching of camptothecin,which suggest the formation of ground-state camptothecin-DNA complex.The binding constant and number of binding site were calculated and the main interaction force was determined.The effect of salt,phosphate and negatively charged quencher KI on camptothecin-DNA interaction was investigated and the interaction of camptothecin with double-stranded DNA and single-stranded DNA was compared.The melting temperature of camptothecin-DNA complex was 60 ℃,which is 18 ℃ lower than that of pure DNA.All the results indicate that groove binding mode is the main interaction mode between camptothecin and DNA.

This paper studied how to improve the glass surface strength.The manufacture process in which the surface strength of glass changes was explored.According to the values of surface strength variation and the strength curves under different grinding processes,the reasons that the surface strength decreased and the related measures were given.Then,the etching method for releasing stress concentration and the max surface compressive stress strengthening theory were described,and the effects of different material removal modes on the surface strength of brittle materials were analyzed.A ductile grinding mode was introduced and its main manufacture requirements were given.The roughness ranges for different non-imaging surfaces were summarized,and corresponding solutions were advanced.The experiments show that as the material removal rate is set to be less than or equal to 25 μm/h and the abrasive size less than or equal to 15 μm,the polishing-similar surface will be achieved for several materials.The ductile grinding can induce an increase of the max surface compressive stress and avoid longitudinal micro-cracks which reduce the glass surface strength,so it is a reasonable grinding mode for glass surface strength improvement.

To assure the pointing accuracy in a shooting target to be better than 30 μm for the Shen Guang Ⅲ(SGⅢ)facility,the switchyard of target area for the facility was designed and the rigid frame and transport mirrors in the switchyard were optimized to improve their stability.In design,the reinforced concrete was used to support the switchyard,and the tilted supports were added in the steel frame of switchyard to decrease and distribute the mass load reasonably.Furthermore,the herringbone supports were firmed to local horizontal beams.The transport mirror supports were also designed,in which their foundational frequencies were much higher than that of the swichyard.By above ways,the angle shifts of transmission mirrors in random broadband vibration can be suppressed successfully.The mechanical analysis of range structure by Finite Element Analysis(FEA) indicates that 87% of transport mirrors show their angle shifts less than 0.48 μrad.According to the relation between the rotation drifts of the optics components and the positioning errors of optical path,it can be seen that the rotation drifts of the transmission mirrors could meet the stability requirements for the positioning error of each single optical path not more than 12.9 μm.