石英晶体微平衡法测定CO_2在聚合物中的溶解度

将石英晶体微平衡法 (QCM )用于气体在聚合物中溶解度的测定 ,实测的CO2 在尼龙 66、天然橡胶和聚氯乙烯中的溶解度与文献值符合较好 .测定了CO2 在聚苯乙烯、聚甲基丙烯酸甲酯和聚甲基丙烯酸正丁酯 3种均聚物及苯乙烯 甲基丙烯酸甲酯共聚物、苯乙烯 丁二烯 苯乙烯共聚物、甲基丙烯酸正丁酯 甲基丙烯酸二甲基氨基乙酯共聚物和甲基丙烯酸正丁酯 丙烯酸全氟烷基乙基酯共聚物等嵌段共聚物中的溶解度 ,并用链状流体状态方程对实验数据进行了关联 。

压电晶体微平衡法测定溶剂在高分子中的扩散系数

建立了应用压电晶体微平衡法测定溶剂在高分子中的吸收动力学曲线的实验装置，测定了２９８～３１３Ｋ范围内乙酸乙酯和丁酮在聚苯乙烯、聚甲基丙烯酸甲酯、聚酞酸二烯丙酯三种高分子中的吸收曲线，并获得了溶剂的平均扩散系数和平衡溶解度。用溶剂在玻璃态高分子膜中的传递模型对所得吸收曲线进行了关联，对Ｓ型吸收曲线取得令人满意的关联效果，但该模型不适用于双平衡型吸收曲线的关联。

相平衡和径向分布函数(Ⅱ)——计算径向分布函数的微相平衡法

在本文(Ⅰ)报中提出的双阻力模型和质量通量准则的基础上,通过考虑任一微相和无序空间的相平衡,将径向分布函数用局部俘获率和局部位能解析性地表达出来,并解决了局部俘获率和局部位能的计算问题。由于计算公式的解析性,本文的计算速度远远高于分子模拟和积分方程理论。计算结果与分子模拟的结果吻合良好,在第1峰附近,优于积分方程的结果。

溶剂小分子在嵌段高分子膜中传递性质的研究

通过压电晶体微平衡法 (QCM法 )获得了乙醇、甲苯在由聚乙酸乙烯酯和聚甲基丙烯酸酯组成的嵌段共聚物中扩散的实验曲线 ,在由 Voigt蠕变模型和 Flory- Huggins混合模型建立的传递模型基础上 ,通过吸入吸附对扩散的影响 ,得到改进的传递模型 ,用以关联实验曲线 ,结果吻合良好。

Optimal estimation of zonal velocity and transport through Luzon Strait using variational data assimilation technique

A P-vector method was optimized using variational data assimilation technique, with which the vertical structures and seasonal variations of zonal velocities and transports were investigated. The results showed that westward and eastward flowes occur in the Luzon Strait in the same period in a year. However the net volume transport is westward. In the upper level (0m -500m),the westward flow exits in the middle and south of the Luzon Strait, and the eastward flow exits in the north. There are two centers of westward flow and one center of eastward flow. In the middle of the Luzon Strait, westward and eastward flowes appear alternately in vertical direction. The westward flow strengthens in winter and weakens in summer. The net volume transport is strong in winter (5.53 Sv) but weak in summer (0.29 Sv). Except in summer, the volume transport in the upper level accounts for more than half of the total volume transport (0m bottom). In summer, the net volume transport in the upper level is eastward (1.01 Sv), but westward underneath.

Forced Resonance of a Slightly-Curved Hydraulic Pipe Fixed at Two Ends

The ideally straight hydraulic pipe is inexistent in reality. The initial curve caused by the manufacturing or the creep deformation during the service life will change the dynamic character of the system. The current work discusses the effect of the initial curve on the hydraulic pipe fixed at two ends for the first time. Based on the governing equation obtained via the generalized Hamilton’s principle,the potential energy changing with the height of the initial curve is discussed. The initial curve makes the potential energy curve asymmetric,but the system is always monostable. The initial curve also has very important influence on natural frequencies. It hardens the stiffness of the first natural mode at first and then has no effect on this mode after a critical value. On the contrast,the second natural frequency is constant before the critical value but increases while the height of the initial curve exceeds the critical value. On account of the initial value,the quadratic nonlinearity appears in the system. Forced resonance is very different from that of the ideally straight pipe under the same condition. Although the 2∶1 internal resonance is established by adjusting the height of the initial curve and the fluid speed,the typical double-jumping phenomenon does not occur under the initial curve given in the current work. This is very different from the straight pipe in the supercritical region. The work here claims that the initial curve of the hydraulic pipe should be taken into consideration. Besides,more arduous work is needed to reveal the dynamic characters of it.

The effect of surface anisotropy on contact angles and the characterization of elliptical cap droplets

In this paper, the variation of contact angles of a droplet on grooved surfaces was studied from microscale to macroscale experimentally and theoretically. The experimental results indicated that the contact angle changes nonlinearly with anisotropic factor. To get clear of the changing process of contact angle on grooved surfaces from microscale to macroscale, we carried out theoretical analysis with moment equilibrium method being adopted. In addition, the variation of contact angles in different directions was investigated and a mathematic model to calculate arbitrary contact angles around the elliptic contact line was suggested. For the convenience of potential applications, a symbolic contact angle was proposed to characterize the ellipsoidal cap droplet on grooved surfaces. Our results will offer help to the future design of patterned surfaces in practical applications,and deepen the understanding of wetting behavior on grooved surfaces.

Axisymmetric 3:1 internal resonance of thin-walled hyperelastic cylindrical shells under both axial and radial excitations

Nonlinear vibration with axisymmetric 3:1 internal resonance is investigated for an incompressible neo-Hookean hyperelastic cylindrical shell under both axial and radial harmonic excitations.A full nonlinear strain-displacement relation is derived from the large deflection theory of thin-walled shells.A set of nonlinear differential equations describing the large deflection vibration are formulated by the Lagrange equation and the assumption of small strains.Steady-state responses of the system are predicted via the harmonic balance method with the arc length continuation,and their stabilities are determined via the modified sorting method.The effects of excitations on the steady-state responses are analyzed.The results reveal a crucial role played by the phase difference in the structural response,and the phase difference can effectively control the amplitude of vibration.