Ion emission from warm dense matter produced by irradiation with a soft x-ray free-electron laser

We report on an experiment performed at the FLASH2 free-electron laser(FEL)aimed at producing warm dense matter via soft x-ray isochoric heating.In the experiment,we focus on study of the ions emitted during the soft x-ray ablation process using time-of-flight electron multipliers and a shifted Maxwell–Boltzmann velocity distribution model.We find that most emitted ions are thermal,but that some impurities chemisorbed on the target surface,such as protons,are accelerated by the electrostatic field created in the plasma by escaped electrons.The morphology of the complex crater structure indicates the presence of several ion groups with varying temperatures.We find that the ion sound velocity is controlled by the ion temperature and show how the ion yield depends on the FEL radiation attenuation length in different materials.

Cascade Catalysts Based on Colloidal Engineering

We see significant progress in the preparation of nanoreactors that host incompatible catalysts for cascade reactions,yet their preparation typically requires specialized,multistep synthetic routes.Here,we utilize core-satellite microparticles as a versatile strategy for the site isolation of catalysts in core and satellites.The core-satellite clusters are prepared by mixing specific amounts of negatively charged core microparticles(e.g.,acid catalyst)with positively charged satellites(e.g.,base catalyst).Core and satellite are made from incompatible polymers allowing solvent-annealing of clusters into different morphologies(raspberry,patchy,and core-shell)while maintaining site isolation of the catalysts.The core-satellite microparticles show very good catalytic activity in a model one-pot acid/base cascade reaction with subtle differences regarding particle morphology.Raspberry microparticles thereby demonstrated the highest reaction rate and yield,likely due to an alleviated diffusion pathway for the reactants.Finally,we show that this colloidal engineering strategy can be extended to multifunctional microparticles suitable to perform multistep cascade reactions in one pot.

Coassembly of Macrocyclic Amphiphiles for Anti-β-Amyloid Therapy of Alzheimer’s Disease

Based on the amyloid hypothesis,anti-β-amyloid(Aβ)therapy has dominated clinical trials for the prevention and treatment of Alzheimer’s disease(AD)in recent years.A key element of this strategy is the interaction between therapeutic agents and Aβ.However,the design and development of artificial receptors that may render selective and strong recognition toward Aβremains a huge challenge because of the complexity and size of peptide guests and their flexible conformation.

类液晶作为高性能有机场效应晶体管的有源层

高载流子迁移率和器件性能的一致性对于有机场效应晶体管在阵列和集成电路上的应用至关重要.然而,同时具备高性能和小批间差的方法当前仍然是个挑战.本论文在原子力显微镜和偏振荧光显微镜表征的基础上,报道了在PTCDI-C1_(3)分子模板上生长具有大晶畴的dif-TES-ADT类液晶状薄膜的方法.我们进一步将所获得的薄膜用作有机场效应晶体管的载流子传输通道,其饱和载流子迁移率高达1.62±0.26 cm^(2)V^(-1)s^(-1).更重要的是,在重复三个批次之间,每次50个器件的迁移率批间差仅为16%.这一发现为设计材料和器件结构以同时实现高载流子迁移率和器件均匀性提供了一种新思路.