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The influences of uncertainties in nuclear physics inputs on the Th/U, Th/Hf, Th/Eu, Th/Os, Th/Ir nucleo-chronometers are investigated in the framework of the classical r-process approach. A Monte-Carlo method is used to evaluate the age uncertainty originating from neutron separation energies for each nuclear mass model. It is found that the deduced age uncertainty for Th /U can be up to 1.66 Ga, and for the three chronometers, Th/Eu, Th/Os, Th/Ir, the uncertainties are 5.15 Ga, 3.93 Ga and 3.95 Ga, respectively. The recently proposed chronometer, Th/Hf, shows a clear model dependence, while Th/Os and Th/Ir chronometers tend to overestimate the age of Universe. Taking into account the uncertainties in nuclear physics inputs and observations, an up-to-date age estimation for the universe with the Th/U chronometer is 14.1? 3.8 Ga.

The contrast of birefringence images of dislocation in synthetic quartz crystal have been calculated with anisotropic elasto-optical coeffficients. Using reflection polarizing microscopy to compensate the natural optical activity, along the optical axis, we obtained the images of edge dislocations and compared it with the calculation.