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In this paper, the influence of calcium on coal gangue and fly ash geopolymer is explored, and the problem of low utilization of unburned coal gangue is analyzed and solved. The experiment took uncalcined coal gangue and fly ash as raw materials, and a regression model was developed with the response surface methodology. The independent variables were the CG content, alkali activator concentration, and Ca(OH)2 to NaOH ratio (CH/SH). The response target value was the coal gangue and fly-ash geopolymer compressive strength. The compressive strength tests and the regression model obtained by the response surface methodology showed that the coal gangue and fly ash geopolymer prepared with the content of uncalcined coal gangue is 30%, alkali activator content of 15%, and the value of CH/SH is 1.727 had a dense structure and better performance. The microscopic results demonstrated that the uncalcined coal gangue structure is destroyed under an alkali activator’s action, and a dense microstructure is formed based on C(N)-A-S-H and C-S-H gel, which provides a reasonable basis for the preparation of geopolymers from the uncalcined coal gangue.

A series of tests investigating the damage effects of fluid-filled submunitions by high velocity projectile impact were conducted. An analytical model is presented, in which the yaw angle of the projectile was taken into account. Based on the analytical model, the influence of the strike angle, hit-point offset distance and projectile length to diameter ratio on submunition damage ratio were predicted. The analytical results showed a good agreement with the experiments. The submunition damage ratio strongly depends on the hit-point offset distance, showing a significant decrease with increasing hit-point offset distance. For large hit-point offset distance, increasing the length to diameter ratio of the projectile will effectively improve the submunition damage ratio. There is an appropriate yaw angle of the projectile in which the submunition damage ratio will be maximal.

An investigation of the copolymerization of allyl glycidyl ether (AGE) with methyl acrylate (MA) was performed in the presence of benzyl imidazole-1-carbodithioate (BICDT) on the thermal initiation condition. Results showed that the process has good characteristics of living free radical polymerization, i.e. the molecular weight of the obtained polymer increases linearly with monomer conversion, molecular weight distribution is very narrow, and a linear relationship between ln([M]0/[M]) and polymerization time is found. The copolymer structure containing epoxy groups was demonstrated from the 1H nuclear magnetic resonance (1H NMR) spectrum. It was found that the content of AGE in the copolymer increases with the increase in monomer conversion and molar faction of the AGE in the monomer feed. However, the polymerization could slow down when the fraction of AGE increases in the monomer feed. Taking advantage of living polymerization character, functional block copolymers PSt-b-P (MA-co-AGE) were prepared in the presence of PSt RAFT agent.

Previous reports indicated that AtMYB103 has an important role in tapetum development, callose dissolution, and exine formation in A. thaliana anthers. Here, we further characterized its function in anther development by expression pattern analysis, transmission electron microscopy observation of the knockout mutant, and microarray analysis of downstream genes. A total of 818 genes differentially expressed between ms188 and the wild-type were identified by global expression profiling analysis. Functional classification showed that loss-of-function of AtMYB103 impairs cell wall modification, lipid metabolic pathways, and signal transduction throughout anther development. RNA in situ hybridization confirmed that transcription factors acting downstream of AtMYB103 (At1g06280 and At1g02040) were expressed in the tapetum and microspores at later stages, suggesting that they might have important roles in microsporogenesis. These results indicated that AtMYB103 is a crucial regulator of Arabidopsis anther development.