Closed all optical cycles in optical networks may generate lasing which adversely affects network performance.

The structure growth and optimization of quantum-dot lasers are introduced firstly, then the optoelectronic properties are discussed in the term of spectrum and modeling, and the dynamic characters of quantum-dot lasers such as homogeneous broadening of optical gain, lasing spectrum control, transition property of excited state etc.

In this thesis, we studies the dispersion,lasing and condensation of exciton-polariton in ZnO nanorod with a hexagonal cross-section which acts as a whispering gallery microcavity(WGM) at room temperature.

A weakening reflected shock wave method in oscillating tube;

The results indicated that the overpressure of reflected shock wave was much stronger,which was about 2 times higher than that of incoming shock wave.

Angular resolution techniques of laser radiation;

Experimental study on detection of laser radiation direction;

Selection and application of instruments for laser radiation measurement;

Fluorescence spectra of HgZn excimer and stimulated emissions of Hg excited by 307.6nm laser pulses;

The stimulated emission was achieved in the blue wavelength region with the peak at 450nm.

The technique of laser light scattering and the study on properties of flocculants;

Measurement of concentration distributions for the dispersed phase flow in a mixing reactor with the laser light scattering by particles;

Analyzed to the construction of production; detected the ratio-surface area of powder and the detection value of laser light scattering contrast.

Numerical analysis of re-initiation phenomenon induced by shock reflection;

In order to investigate a new technique shock reflection detonation initiation for kerosene/air pulse detonation engine,the circular orifice plates and the wedge obstacles were designed.

Through comparing different results of simulating shock reflection flow over a forward step using different schemes including Roe and van Leer schemes,the advanced upwind scheme(AUSM+) is fully studied in terms of its resolution and efficiency for shock waves,expansion vaves,contact discontinuities and their interactions.