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To study load carrying capacity for Lap Region between the Skirt and Composite Case(LRSC) of the solid rocket motor(SRM),made the stress of layer out of skirt as the research object, established the two-dimensional axisymmetric finite element model for compsite case,analysed the main factor(lap length) for carrying capacity of LRSC,and verified the conclusions by calculation.Optimized the lap length ranged from 40mm to 60mm, proposed model of the optimal lap length and optimization method,calculated optimal lap length under different axial loads.The results show that, with the increase of lap length of skirt, the load bearing capacity of LRSC enhances first and depresses then,exists a great value,which of the corresponding lap length is optimal;With the increase of axial load,optimal lap length monotonously will increase.

A320 series aircraft carbon/carbon brake materials were prepared by processing a needle-punched carbon fiber preform with quasi-three-dimensional integrity. The preform was first impregnated with a resin and heated to 800℃ to convert the resin to carbon. This was followed by chemical vapor infiltration (CVD) using propylene as the source gas and a radial thermal gradient (”external heating, internal cooling” or ”internal heating, external cooling”). For the CVD process the performs were separated by graphite pads to allow free flow of propylene along the channels thus formed. The final brake discs were obtained by a further high-temperature treatment from 1600-2400℃. These carbon brake discs were compared with the advanced discs made abroad in terms of ground test and service performance. The two kinds of carbon brakes have the same friction coefficients under the designed landing energy and overload energy braking condition for A320 airplanes. Especially, under the aborted take-off condition, the friction coefficient of the domestically developed carbon brake disc was 21-48% higher and the static friction coefficient was 28% higher than that of the ones provided by the aircraft manufacturer. The average brake service life exceeds 2700 landings, 24% times larger than the original ones.

A chiral selector was prepared through the reaction between (1S,2R)-(+)-2-amino-1,2-diphenylethanol and phenyl isocyanate. This selector was immobilized on aminated silica gel, respectively, with bifunctional group linkers of 1,4-phenylene diisocyanate, methylene-di-p-phenyl diisocyanate, and terephthaloyl chloride to produce corresponding three chiral stationary phases. The prepared compounds and chiral stationary phases were characterized by FT-IR, elemental analysis, 1H NMR, and solid-state 1H NMR. The enantioseparation ability of these chiral stationary phases was evaluated with structurally various chiral compounds. The chiral stationary phase prepared with 1,4-phenylene diisocyanate as linker showed excellent enantioseparation ability. The influence of different linkages on the enantioseparation was discussed. Chirality, 2009. © 2008 Wiley-Liss, Inc.