The branch points in laser propagation through atmosphere are detected with 30×30 HartmannShack wave-front sensor. It is shown that there is branch points in beacon light phase in strong scintillation, and the results agree with the simulated data. It is proved that branch points appear in pair. The branch point problem is computed by four-dimension code of laser propagating in atmosphere. The effects of emission diameter and grid precision on the position and account of branch points are analyzed.

For studying the effects of technical parameters of the airborne dual-wavelength Mie lidar on its detection performance, offering theoretic evidence for the lidar's design and development, the airborne Mie scattering lidar equation, appropriate atmospheric extinction model, as well as the design parameters of the lidar are used to calculate atmospheric backscattering signal profiles and the signal-to-noise ratio(SNR)profiles received by the lidar. The effects of overlap function and different atmospheric models on the signal are discussed, and the influences of some technical parameters of the lidar on the SNR are analyzed, such as laser pulse energy, number of accumulated laser pulses, field of view, and filter bandwidth. The results show that the lidar with these design parameters is capable of detecting aerosol and clouds below 10 km altitude.

Based on the hourly data of 31 rain gauges of Anhui province and Hefei radar echo data, the correlation between radar echo data and rainfall data is analyzed, the best elevation angle data of rainfall estimation in different area is studied, and six elevation angles are collected. The size of correlation characterizes the capability of rainfall estimation of Hefei radar. The result indicates that the correlation between 0.5°radar echo data and rainfall data is much higher in most stations. The capability of rainfall estimation of Hefei radar is higher in center of Anhui province and Huaihe River coastwise area than other areas; it is lower in provincial boundary.

Optical turbulence forecast plays an important role in optical engineering applications; however,no related work has been reported yet in China. Mesoscale weather forecast model MM5, its flow chart and coordinate system are introduced; based on its result with Dewan optical turbulence parameterization, 48 hours' refractive index structure constants of Hefei, Kuerle and Dongshan are forecasted, and turbulence profiles of every time record and profile charts of refractive index structure constant are shown. The results consist with normal characteristics of magnitude and tendency of refractive index structure constant varying with height, but there are differences among these places. Brief analysis is given to explain these differences.As there is no comparison with observations, the results need to be further checked by experiments for future applications.

The total internal partition sums of formaldehyde were calculated by Fortran90 program. At the same time the line intensities of 000010-000000 and 100000-000000 transition bands of formaldehyde at several temperatures ranging from 296 to 3000 K were computed. Results showed that at this temperature range the agreement between the calculated line intensities and those extrapolated from HITRAN database is fairly good, which provides a strong support for the calculations of partition function and line intensity at high temperature. Then, the line intensities and spectral simulations at the higher temperature 4000 K are presented.

Several methods were used to measure the atmosphere corrosion rusty layer of the carbon steel A3 and low-alloy steel lOCrMoAl samples from Qingdao. The structure, appearance of steel rusty layer, exisence of alloy elements of steel rest body were disscussed. The main component elements and rust phase of the rusty layer were observed, showing that the relative content of the elements and rust phase varied with the change in corrosion time. The mechanism of the anti-corrosion of the steel was put forward.