Velocity distribution of elliptical galaxies in the framework of Non-local Gravity model

We investigate the velocity distribution of elliptical galaxies in the framework of Non-local Gravity. According to this approach, it is possible to recover the fundamental plane of elliptical galaxies without the dark matter hypothesis. Specifically, we compare theoretical predictions for circular velocity in Non-local Gravity context with the corresponding values coming from a large sample of observed elliptical galaxies. We adopt the surface brightness, effective radius and velocity dispersion as structural parameters for the fundamental plane. As final result, it is possible to show that non-local gravity effects can reproduce the stellar dynamics in elliptical galaxies and fit consistently observational data.     

环氧树脂改性交联剂的制备及其对室温硫化硅橡胶性能的影响

力学性能差是制约室温硫化硅橡胶应用发展的主要因素，而交联剂结构对力学性能有重要影响。为提高室温硫化硅橡胶的力学性能，本文以环氧树脂E-44与氨丙基三烷氧基硅烷为原料通过开环反应合成了一种改性交联剂（E44-APS），通过红外光谱、核磁氢谱确定了E44-APS的结构，并研究了E44-APS交联剂对室温硫化硅橡胶拉伸性能、固化性能、接触角、表面形貌、热稳定性的影响。结果表明，随E44-APS含量增加，室温硫化硅橡胶的拉伸强度先增加后降低，当E44-APS用量为10% 时，拉伸强度和断裂伸长率最大可达0.47 MPa和306%；固化时间随E44-APS用量增加而增加；5%热失重温度随E44-APS用量增加而降低；接触角随E44-APS用量增加先降低后增加。上述结果表明E44-APS可有效提高室温硫化硅橡胶的力学性能，同时会带来一些负面影响，如固化时间延长和热稳定性下降及疏水性下降等。