The stability and stabilization of the motion of non-conservative mechanical systems

Two stability problems are solved. In the first, the stability of mechanical systems, on which dissipative, gyroscopic, potential and positional non-conservative forces (systems of general form) act, is investigated. The stability is considered in the case when the potential energy has a maximum at equilibrium. The condition for asymptotic stability is obtained by constructing Lyapunov's function. In the second problem, the possibility of stabilizing a gyroscopic system with two degrees of freedom up to asymptotic stability using non-linear dissipative and positional non-conservative forces is investigated. Stability of the gyroscopic system is achieved by gyroscopic stabilization. The stability conditions are obtained in terms of the system parameters. Cases when the gyroscopic stabilization is disrupted by these non-linear forces are indicated.     

丙二酰二腙衍生的二氧化二钼(Ⅵ)配合物的合成、表征和晶体结构

本文报道了二氧杂钼(Ⅵ)配合物[MoO₂(H₂L)(H₂O)]的合成、表征和分子结构。该配合物是由马来酰二腙配体双(2-羟基-1-萘醛)丙二酰二腙(H₄L)与双(乙酰丙酮)二氧钼(Ⅵ)在甲醇中以1∶1的物质的量之比反应得到的。通过各种光谱(如IR、MS和NMR)对该配合物进行了表征。通过单晶X射线晶体学确定了配合物的结构。该配合物属于单斜晶系P2₁/c空间群。金属中心具有扭曲的八面体配位环境,与H₂L^2-的1个甲亚胺氮原子、2个末端氧基团、H₂L^2-的2个氧原子和配位水分子的1个氧原子相连。     

丙二酰二腙衍生的二氧化二钼(Ⅵ)配合物的合成、表征和晶体结构

本文报道了二氧杂钼(Ⅵ)配合物[MoO₂(H₂L)(H₂O)]的合成、表征和分子结构。该配合物是由马来酰二腙配体双(2-羟基-1-萘醛)丙二酰二腙(H₄L)与双(乙酰丙酮)二氧钼(Ⅵ)在甲醇中以1∶1的物质的量之比反应得到的。通过各种光谱(如IR、MS和NMR)对该配合物进行了表征。通过单晶X射线晶体学确定了配合物的结构。该配合物属于单斜晶系P2₁/c空间群。金属中心具有扭曲的八面体配位环境,与H₂L^2-的1个甲亚胺氮原子、2个末端氧基团、H₂L^2-的2个氧原子和配位水分子的1个氧原子相连。