• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nanotechnology >Dynamic phonon scattering rates of nanosurfaces with gas particles
【24h】

Dynamic phonon scattering rates of nanosurfaces with gas particles

机译：带有气体粒子的纳米表面的动态声子散射速率

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The scattering rate of a nanosurface lattice interfaced with a gaseous boundary is derived and characterized. Gas particle collisions with crystal lattice atoms are found to exhibit dynamic behavior under varying gas flow speeds, accommodation coefficients and gas atomic/molecular masses. Numerical results of SiO2 in a stationary N2 atmosphere predict scattering rates ranging from 7.6 ps at 0.1 accommodation to 0.69 ps at full accommodation. Varying the inert gas masses was found to induce shorter carrier lifetimes of 0.23 ps for Xe/SiO2 compared to 1.2 ps for He/ SiO2. Additional results show longer phonon lifetimes for Ar and Ne compared to He, which is attributed to a greater He collision rate that exceeds the effects of heavier Ar and Ne perturbations. Comparison of the lattice - gas scattering rates to the scattering rates of adsorbed gas particles at 50% surface coverage show a 44% contribution to the total nanosurface - gas scattering component. The lattice - gas scattering effects on transport coefficients are investigated through thermal conductivity. Numerical predictions of thermal conductivity for a SiO2 thin- film structure are first correlated to experimental data then characterized in both a stationary and flowing N-2 atmospheres. Decreases of 12% and 18% are predicted for stationary and Mach 0.9 flow velocity respectively, indicating that nanosurface-gas interactions can substantially impact transport coefficients when interfaced with gaseous boundaries. In order to gauge the magnitude of gaseous scattering effects, a dimensionless scattering number for nanosurface-gas systems is introduced as a ratio of the nanostructure characteristic dimension and gas particle surface interaction distance.
机译：推导并表征了与气体边界交界的纳米表面晶格的散射速率。发现与晶格原子的气体粒子碰撞在变化的气体流速，容纳系数和气体原子/分子质量下表现出动态行为。 SiO2在固定N2气氛中的数值结果预测，散射速率的范围从0.1调节时的7.6 ps到完全调节时的0.69 ps。发现惰性气体质量的变化会导致Xe / SiO2的载流子寿命较短，为0.23 ps，而He / SiO2的载流子寿命为1.2 ps。其他结果表明，与He相比，Ar和Ne的声子寿命更长，这归因于更高的He碰撞率，其超过了Ar和Ne扰动的影响。在50％的表面覆盖率下，晶格-气体散射率与吸附的气体颗粒的散射率的比较显示，纳米表面-气体散射总成分的贡献率为44％。通过热导率研究了晶格-气体散射对传输系数的影响。 SiO2薄膜结构的热导率数值预测首先与实验数据相关，然后在固定和流动的N-2气氛中进行表征。固定流速和0.9马赫数的流速分别下降12％和18％，表明纳米表面-气体相互作用在与气态界面接触时会显着影响传输系数。为了测量气体散射效应的大小，引入了纳米表面-气体系统的无量纲散射数，作为纳米结构特征尺寸与气体颗粒表面相互作用距离的比率。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号