The basicity, water solubility, intrinsic viscosity and molecular weight of carboxymethyl chitosan (CM-chitosan) were investigated. The solution pH remained at about 9.2 at the concentration of higher than 2.0 g/L. The isoelectric point of CM-chitosan was about 4.5 of pH, and the solubility of CM-chitosan at the solution pH of 2.0 to 6.0 was lower than 5 g/L. The acetic acid could be replaced by hydrochloric acid as solvent for the viscosity-average molecular weight determination of chitosan. The intrinsic viscosity values of CM-chitosan have significant differences in acidic and alkaline conditions. The viscosity-average molecular weight of CM-chitosan was (3.8 ± 0.2) × 105, consistent with that of product chitosan of blank test.

This paper contraposed the reliability analysis of deployment mechanism of solar arrays. First, the configuration and function of solar arrays were described briefly. According to the deploying principle of mechanism, the model of the reliability was established in order to make the calculation and analysis of structural reliability. There was some propose to improve the reliability of the system according to the weakness from the analysis. Secondly, from two aspects of static torque margin and torque, the motor function reliability analysis of deployment mechanism of solar arrays was developed

Oval bevel gear is a kind of noncircular bevel gear which can achieve variable transmission between intersecting axes. We design the pitch curve by spherics cosine theorem in spatial polar coordinate because the pitch curve of oval bevel gear is not the planar curve. The bevel gear cutter is introduced, and we get the Three-dimensional model of oval bevel gear through extended development of UG. This method can make the calculation accurately, easily and get a wide variation of transmission ratio.

Thermal cycling was applied to assess the effect of tin-lead solder 63Sn37Pb and lead-free solder 95.5Sn3.8Ag0.7Cu on the reliability of 3D PLUS solder joints. Nonlinear finite element method and viscoplastic Anand model were used to evaluate the stress and strain distribution and dangerous position of solders under the thermal cycling condition. The law of solder joints stress and plastic strain were finally obtained and showed significant cyclical changes. The stress and strain emerged the trend of accumulated enhancement with the process of time, then ultimately stabilized. Comparing two curves of equivalent stress and plastic strain obtained from lead-free and tin-lead solder, it was found that the reliability of 95.5Sn3.8Ag0.7Cu was better than that of 63Sn37Pb.

Based on analysis of problems in spaceflight products R&D data process and management, a solution is proposed in this paper. An analysis and experimental data processing and managing system is realized in a WEB environment based on B/S frame. This paper has also introduced the composition and principle of the system.