Heterogeneous ice nucleation induced by porous materials

冰粒的成核对云的形成和随后的降水起着重要作用，对大气化学、云物理和地球气候都有影响。为了量化和预测云对天气预报和气候的影响。模型，冰粒子的形成必须以一种现实的方式来描述。最重要的形成机制之一是浸没模式下的非均质冰核，在这种模式下，冰核的表面（例如矿物尘埃颗粒）浸在水滴中形成冰核。在本研究中，我们将进行大量的浸入式冷冻实验。我们将研究大气中以气溶胶粒子形式出现的各种物质的冰核活动。特别是，我们的目标是量化由它们引起的冰核的温度和时间依赖性。我们将特别关注多孔材料诱导冰成核的系统研究。我们想研究这两种材料，合成材料，如介孔二氧化硅，以及天然材料，如微孔沸石。

The nucleation of ice particles plays an important role for the formation of clouds and subsequent precipitation, with implications for atmospheric chemistry, cloud physics and Earth's climate. In order to quantify and predict the effects of clouds in weather forecast and climate.models, ice particle formation has to be described in a realistic manner. One of the most important fomiation mechanisms is heterogeneous ice nucleation in the immersion mode, in which ice is initiated at the surface of an ice nucleus - for example a mineral dust particle - immersed in an aqueous droplet. We will perform numerous immersion freezing experiments during this study. We will investigate the ice nucleation activity of various materials that occur in the form of aerosol particles in the atmosphere. In particular, we aim at quantifying the temperature and time dependence of the ice nucleation induced by them. A special focus will be on the systematic study of ice nucleation induced by porous materials. We want to investigate both, synthetic materials such as mesoporous silica as well as naturally occurring materials such as microporous zeolites.