Electrostatic sheath at the boundary of a collisional dusty plasma

Considering the Boltzmann response of the ions and electrons in plasma dynamics and inertial dynamics of the dust charged grains in a highly collisional dusty plasma, the nature of the electrostatic potential near a boundary is investigated. Based on the fluid approximation, the formation as well as the characteristic behaviours of the sheath is studied. It is expected that the presence of dust charged grains will lead to a very different behaviour of the sheath as compared to that of electron-ion plasma. Moreover, the collisions of the dust charged grains with the neutrals are expected to exhibit novel features.     

热等离子体科学技术的现状和发展

概述了热等离子体科学技术的现状和发展,介绍了一些工业应用和等离子体发生器。      

Shock waves in a rotating non-Maxwellian viscous dusty plasma

A theoretical model is presented to study the characteristics of dust acoustic shock in a viscous, magnetized, rotating dusty plasma at both fast and slow time scales. By employing the reductive perturbation technique, the non-linear Zakharov–Kuznetsov–Burger (ZKB) equation is derived for both cases when the dust is inactive and dynamic (fast and slow time scales). Both electrons and ions are considered to follow the kappa/Cairns distribution. It is observed that in both cases, i.e. when dust is in the background and active, viscosity plays a key role in dissipation for the propagation of acoustic shock. Magnetic field and rotation are responsible for the dispersive term. Superthermality is found to affect significantly the formation of the shock wave along with viscous nature of plasma, whereas the dust charge affects the non-linear coefficient of the ZKB equation. The present investigation may be beneficial to the understanding of the rotating plasma, in particular the experiments being carried out.     

辐射烧蚀区电子温度研究

此文叙述了采用晶体谱仪测量辐射烧蚀区电子温度的方法.在"星光Ⅱ”激光装置上,以波长为0.35μm,能量～70J,脉宽～700ps的强激光注入辐射烧蚀靶,实验首次测到了辐射烧蚀样品自发射谱,配合理论计算,给出了碳氢样品电子温度29eV.另外用空间分辨晶体谱仪研究了发泡铝靶电子温度空间分布;用双示踪元素等电子谱线法研究了Formvar(CHO)膜平面靶的电子温度.     

Simultaneous Harvesting of Multiple Hot Holes via Visible-Light Excitation of Plasmonic Gold Nanospheres for Selective Oxidative Bond Scission of Olefins to Carbonyls

Using visible photoexcitation of gold nanospheres we successfully demonstrate the simultaneous harvesting of plasmon-induced multiple hot holes in the complete oxidative scission of the C=C bond in styrene at room temperature to selectively form benzaldehyde and formaldehyde, which is a reaction that requires activation of multiple substrates. Our results reveal that, while extraction of hot holes becomes efficient for interband excitation, harvesting of multiple hot holes from the excited Au nanospheres becomes prevalent only beyond a threshold light intensity. We show that the alkene oxidation proceeded via a sequence of two consecutive elementary steps; namely, a binding step and a cyclic oxometallate transition state as the rate-determining step. This demonstration of plasmon-excitation-mediated harvesting of multiple hot holes without the use of an extra hole transport media opens exciting possibilities, notably for difficult catalytic transformations involving multielectron oxidation processes.