In 19 phytoplankton samples collected from 14 water bodies in the southeastern part of China and examined by electron microscopy, 27 taxa of silica-scaled chrysophytes (8 of them belonging to the Chrysophyceae and 19 ...In 19 phytoplankton samples collected from 14 water bodies in the southeastern part of China and examined by electron microscopy, 27 taxa of silica-scaled chrysophytes (8 of them belonging to the Chrysophyceae and 19 to the Synuriphyceae) were found. All these taxa are new to Fujian province;24 of them were previously found in China, but 3, viz. Chrysosphaerella septispina, Mallomonas rasilis and M. guttata var. simplex are new to China. M. guttata var. simplex has only been reported from the Ontario region, Canada. The silica-scaled chrysophyte flora and their geographical distribntion in thisregion are discussed.展开更多
High temperature annealing is often used for the stress control of optical materials.However,weight and viscosity at high temperature may destroy the surface morphology,especially for the large-scale,thin and heavy op...High temperature annealing is often used for the stress control of optical materials.However,weight and viscosity at high temperature may destroy the surface morphology,especially for the large-scale,thin and heavy optics used for large laser facilities.It is necessary to understand the thermal behaviour and design proper support systems for large-scale optics at high temperature.In this work,three support systems for fused silica optics are designed and simulated with the finite element method.After the analysis of the thermal behaviours of different support systems,some advantages and disadvantages can be revealed.The results show that the support with the optical surface vertical is optimal because both pollution and deformation of optics could be well controlled during annealing at high temperature.Annealing process of the optics irradiated by CO2 laser is also simulated.It can be concluded that high temperature annealing can effectively reduce the residual stress.However,the effects of annealing on surface morphology of the optics are complex.Annealing creep is closely related to the residual stress and strain distribution.In the region with large residual stress,the creep is too large and probably increases the deformation gradient which may affect the laser beam propagation.展开更多
文摘In 19 phytoplankton samples collected from 14 water bodies in the southeastern part of China and examined by electron microscopy, 27 taxa of silica-scaled chrysophytes (8 of them belonging to the Chrysophyceae and 19 to the Synuriphyceae) were found. All these taxa are new to Fujian province;24 of them were previously found in China, but 3, viz. Chrysosphaerella septispina, Mallomonas rasilis and M. guttata var. simplex are new to China. M. guttata var. simplex has only been reported from the Ontario region, Canada. The silica-scaled chrysophyte flora and their geographical distribntion in thisregion are discussed.
基金Project supported by the Joint Fund of the National Natural Science Foundation of China and the China Academy of Engineering Physics (Grant No. 11076008)the Foundation for Young Scholars of University of Electronic Science and Technology of China (Grant No. L08010401JX0806)the Fundamental Research Funds for the Central Universities,China (Grant No. ZYGX2009X007)
文摘High temperature annealing is often used for the stress control of optical materials.However,weight and viscosity at high temperature may destroy the surface morphology,especially for the large-scale,thin and heavy optics used for large laser facilities.It is necessary to understand the thermal behaviour and design proper support systems for large-scale optics at high temperature.In this work,three support systems for fused silica optics are designed and simulated with the finite element method.After the analysis of the thermal behaviours of different support systems,some advantages and disadvantages can be revealed.The results show that the support with the optical surface vertical is optimal because both pollution and deformation of optics could be well controlled during annealing at high temperature.Annealing process of the optics irradiated by CO2 laser is also simulated.It can be concluded that high temperature annealing can effectively reduce the residual stress.However,the effects of annealing on surface morphology of the optics are complex.Annealing creep is closely related to the residual stress and strain distribution.In the region with large residual stress,the creep is too large and probably increases the deformation gradient which may affect the laser beam propagation.
