The water-based materials for mine gas absorption and explosion suppression were prepared, in which the mixed organic aggregate
of Span80 and alkaline salt can be used as methane absorbent. Methane was used as a model of mine gas, and the absorptions
of methane with different complex materials were studied using head space gas chromatography. Then the state of aqueous material
was characterized with laser light scattering instrument and the effects of different complex materials on explosion suppression
were preliminarily studied in explosion chamber which can simulate mine gas explosion. The research results showed that complex
material could absorb methane and there was some correlation between the mean diameter of organic aggregate in aqueous material
and the absorption effect. Additionally, the aqueous material could suppress the methane explosion to some degree. The material
can absorb mine gas in atomization condition, therefore, degrease mine gas concentration and influence the distribution of
mine gas in the space, and then suppress the mine gas explosion to some extent. 相似文献
In this article, we described the synthesis of comb oligomers having rigid racemic or chiral binaphthyl macrocyclic pendant groups via the free radical polymerization. Oligomers obtained were well characterized by MALDI-TOF-MS, 1H NMR, FT-IR, UV, CD and SEC. These comb oligomers having macrocyclic pendant groups showed very good solubility in common organic solvents at room temperature. Furthermore, the oligomers could self-assemble into different morphologies by dropping their THF solutions of different concentrations on the surface of water. At a relatively low concentration, the oligomers self-aggregated into hollow spheres. When the concentration was increased, the aggregates changed into solid spheres. The morphologies of the hollow or solid spheres were observed by TEM and ESEM. 相似文献
This paper focuses on the fundamental problems of linear quadratic gaussian (LQG) control and stabilization problems for networked control systems (NCSs) with unreliable communication channels (UCCs) where packet dropout, input delay and observation delay occur. These basic issues have attracted extensive attentions due to broad applications. Our contributions are as follows. For the finite horizon case, without time-stamping technique, the optimal estimator is derived by using the novelty method of innovation sequences based on the delayed intermittent observations; A necessary and sufficient condition for the optimal control problem is presented on the basis of the solution to the forward and backward difference equations (FBDEs) and two coupled Riccati equations. For the infinite horizon case, it is shown that under certain assumption, the system can stay bounded in the mean square sense if and only if the algebraic Riccati equation admits the unique positive solution.