were theoretically evaluated based on kinetic equations describing the dissolution of hardening 尾" (Mg_2Si) precipitates and the precipitation of non-hardening 尾' (Mg_2Si) precipitates during the weld thermal cycles to quantitatively prove above mentioned advantageous characteristics of laser beam ...
With a Marx generator providing electric fields of up to 180 kV/cm between the cathode and annular anode, a Faraday cup array positioned 10 cm downstream of the anode measures the spatial distribution of the electron beam in this field-free region. although self-induced vacuum breakdown will ...
Laser beam welding can reduce the size of grain of high strength steel joints due to its rapid cooling resulting from its higher energy density and lower heat input. But there are some important problems in joint, such as solidification cracks, HAZ cracks and soften etc. In this paper, char...
RJ Dewhurst,GJ Pert,SA Ramsden - 《Journal of Physics D Applied Physics》 被引量: 4发表: 2002年 Fundamental Research for Lightning Trigger Experiment by Using UV Lasers experiment, the characteristics of a laser-triggered spark gap (LTSG) were examined, where a laser beam was not irradiated ...
To enhance the emission spectrum intensity of laser-induced plasma, a method of combining cavity-enhanced laser-induced breakdown spectroscopy (LIBS) with nanoparticles-enhanced LIBS (NELIBS) was proposed. In this paper, the brass with Au-nanoparticles deposited on the surface is placed under the ...
When a high-power laser beam is focused at a point, the air at the focal point is heated to temperatures of thousands of degrees within several nanoseconds and breaks down. This generates a spark that, in turn, is accompanied by an acoustic shock wave. The acoustic shock waves generated by...
The properties of an electron beam trapped and accelerated in a laser wakefield have been investigated. Plastic scintillating fibers were employed together with position sensitive photomultiplier tubes (PMT) and a series of dipole electro-magnets to study the beam. The measured momentum spectrum peaks ...
The beam propagates as a Gaussian beam at moderate and large distances from the mesh coupler. The maximum output power of the laser is of the order of 100 mW, representing the highest output power per unit volume so far reported for a continuous HCN laser. 展开 ...
A miniature lidar beam steering unit was developed and used to determine the effect of the mirror coatings on the transmitted state of polarization. Results will be presented for pairs of mirrors with different coatings. 关键词: beam steering laser mirrors light polarisation light transmission optical...
The direct integration of the diffraction integral is quite time consuming. Based on the fact that a hard-edge aperture function can be expanded into finit... Y Zhang - 《Optics Communications》 被引量: 41发表: 2005年 Change of the paraxiality of a Gaussian beam diffracted by a circular ap...