Mesoscopic pattern formation of supramolecules incorporated with an autonomous function

具有自主功能的超分子介观图案形成

• 批准号: 13640394
• 负责人: MIYAKAWA Kenji
• 金额: $ 0.45万
• 依托单位: Fukuoka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13640394/
• 关键词: self-organization; stochastic resonance; Belousov-Zhabotinsky reaction; supramolecule; 非平衡; ゲル

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.

采用乳化聚合法制备了以别洛乌索夫- zhabotinsky （BZ）反应钌催化剂Ru(bpy)_3^<2+>为固定化载体的亚微米级聚n-异丙基丙烯酰胺（PNIPA）凝胶。利用Nd^<3+>: YVO_4激光，利用光学捕获技术构建了由多个Ru(bpy)_3^<2+>-co-PNIPAM微凝胶粒子组成的系综。在一定的激光功率下，形成直径约为5μm的颗粒。我们观察到一个氧化波在被捕获的粒子上传播。通过Ru(bpy)_3^<2+>-co-PNIPAM共聚物Ru(bpy)_3^<2+>与PNIPAM共价成键，制备出具有节律性和可逆的线圈球（CG）跃迁的共聚物Ru(bpy)_3^<2+>。通过BZ溶液的透射率在22℃下显示了周期为60 s的振荡曲线。我们利用动态光散射证实了这一现象与有节奏的CG跃迁有关。当红外激光束照射聚合物溶液时，在焦斑附近产生直径约为5μm的软网络结构。该结构随BZ反应呈现出节律性变化。研究了Ru(bpy)_3^<2+>掺杂微凝胶对包括噪声在内的外力的动力学响应。在振荡系统中，当亚阈值周期信号和噪声同时作用于振荡器时，随机共振以噪声增强锁相的形式表现出来。这些实验结果在强迫Oregonator模型的数值模拟中得到了定性再现。在可激系统中，当噪声幅值增加到一定值以上时，出现振荡状态。我们用不同的统计量证明了相干共振的证据。我们证明，在最佳噪声水平下，相干振荡的周期由系统固有动力学的时间尺度决定。

项目成果

Fumitaka Sakamoto: "Asymmetric Spatiotemporal Patterns of Reduction Waves in the Belousov-Zhabotinsky Reaction"J. Phys. Soc. Jpn.. 70. 2263-2266 (2001)

Fumitaka Sakamoto：“别洛乌索夫-扎博廷斯基反应中还原波的不对称时空模式”J。

F.Sakamoto: "Asymmetric Spatiotemporal Patterns of Reduction Waves in the Belousov-Zhabotinsky Reaction"J. Phys. Soc. Jpn.. 70. 2263-2266

F.Sakamoto：“别洛乌索夫-扎博廷斯基反应中还原波的不对称时空模式”J。

K.Miyakawa: "Dynamics of a stochastic oscillator in an excitable chemical reaction system"Phys. Rev. B. (in press).

K.Miyakawa：“可激发化学反应系统中随机振荡器的动力学”Phys。

K. Miyakawa: "Noise-enhanced phase locking in a chemical oscillator system"Phys. Rev. E. 65. 056206-1-056206-5 (2002)

K. Miyakawa：“化学振荡器系统中的噪声增强锁相”Phys。

Kozue Kaibara: "Characterization of Proteinic Coacervate Formation : From Primeval Cell Model to Biofunctionality Materials"Americans Scientific Publishers(発表予定). (2002)

Kozue Kaibara：“蛋白质凝聚层形成的表征：从原始细胞模型到生物功能材料”美国科学出版社（即将出版）（2002 年）。