Mesoscopic pattern formation of supramolecules incorporated with an autonomous function

采用乳化聚合法制备了固定在Belousov-Zhabotinsky(BZ)反应催化剂上的亚微米级聚N-异丙基丙烯酰胺(PNIPA)凝胶。我们利用Nd^&lt；3+&Gt；：YVO4激光，通过光学捕获，构建了由许多Ru(Bpy)_3^&lt；2+&gt；-co-PNIPAM微凝胶粒子组成的系综。在一定的激光功率下，可形成直径约5μm的颗粒。通过将Ru(Bpy)_3^&lt；2+&gt；共价键合到PNIPAM上，我们观察到一个氧化波在被捕获的粒子上传播。透过其BZ溶液的透过率在22℃处呈现出周期为60 S的振荡轮廓。我们利用动态光散射证实了这一现象与节律性的CG跃迁有关。当用红外激光照射聚合物溶液时，在焦斑附近形成了直径约5μm的软网络结构。研究了Ru(Bpy)_3^&lt；2+&gt；掺杂微凝胶对外界强迫和噪声的动态响应。在振荡系统中，当亚阈值周期信号和噪声同时施加在振荡器上时，随机共振表现为噪声增强的锁相形式。这些实验结果在Oregonator强迫模型的数值模拟中得到了定性的再现。在可激发系统中，当噪声幅度增加到一定值以上时，就会出现振荡状态。我们用各种统计量给出了相干共振的证据。我们证明，在最佳噪声水平下，相干振荡的周期由系统本征动力学的时间尺度决定。

Submicron-sized poly(N-isopropyl acrylamide) (PNIPA) gels immobilized the ruthenium catalyst (Ru(bpy)_3^<2+>) of Belousov-Zhabotinsky (BZ) reaction was prepared by emulsification polymerization. We constructed of an ensemble consisting of many Ru(bpy)_3^<2+>-co-PNIPAM micro gel particles by an optical trapping using Nd^<3+>: YVO_4 laser. A particle of ca. 5μm in diameter was formed above a certain laser power. We observed an oxidized wave propagating on the trapped particle.We created a copolymer (Ru(bpy)_3^<2+>-co-PNIPAM) showing rhythmical and reversible coil-globule (CG) transitions by covalently bonding Ru(bpy)_3^<2+> to PNIPAM. A transmittance through its BZ solution showed the oscillation profiles with the period of 60 s at 22℃. We confirmed that this phenomenon is related to the rhythmical CG transition by using a dynamical light scattering. When a polymer solution was irradiated with an IR laser beam, a soft network structure of ca. 5μm in diameter was produced in the vicinity of the focal spot. This structure showed a rhythmical change with the BZ reaction.Dynamical responses of a Ru(bpy)_3^<2+>-doped microgel to external forcing including noise were investigated. In an oscillatory system, when a subthreshold periodic signal and noise were simultaneously imposed on the oscillator, stochastic resonance manifested itself in the form of noise-enhanced phase locking. These experimental findings were qualitatively reproduced in the numerical simulation with a forced Oregonator model . In the excitable system, when a noise amplitude was increased above a certain value, and oscillatory state appeared. We showed the evidence of coherence resonance by using various statistical quantities. We demonstrated that, at an optimal noise level, the period of coherent oscillation is determined by the time scale of the intrinsic dynamics of the system.