Localized Surface Plasmon Resonance of Metallic Nanoparticles--Optical Property Characterization for Rational Applications

在光的激发下金属纳米结构中的自由电子能够发生群体性的振荡，进而产生表面等离激元（SPP）。发生等离激元共振时，金属纳米结构会将光束缚在表面，并在表面产生极强的电场增强。表面等离激元有两种类型：一类具有传播的特点，其表面等离激元能够在表面传播，称之为propagatingSPP；另一类不具有传播性，共振局域在一个很小的金属结构中，称之为localizedSPP，即局域表面等离激元共振（LSPR）。金属纳米颗粒就具有很强的表面等离激元共振的（LSPR）性质，使其对光产生增强的吸收和增强的散射，并表现出相关的热、光电场增强和热电子等效应。近年，随着纳米科技的发展，金属纳米粒子的LSPR效应已经成为一...The collective oscillation of free electrons in metal nanostructures excited with light is called surface plasmon polaritons (SPP). The light will be confined to a small area on the surface under the resonance condition (SPR), thus a giant enhancement in the electric field will be produced. There are two kinds of surface plasmon polaritons (SPP): one is propagating plasmon polaritons (PSPP), which...学位：理学博士院系专业：化学化工学院_物理化学(含化学物理)学号：2052010015366

Qualification of the Titanium Welds in the E-XFEL Cryomodule and the CE Certification

The CE stamping of the one hundred 1.3 GHz cryomodules for the European XFEL Linac is a main step in the process of the certification of the entire Linac as pressure equipment. Stringent requirements on materials and the quality of the welds of the pressurised components need to be satisfied to obtain the stamp. This paper summarizes these requirements, describes the process developed to qualify each module and summarises the rework campaign on the cavity helium vessels made necessary to obtain the required quality for a reliable and safe accelerator