Since Alan Turing’s 1952 pioneering work, reaction–diffusion (RD) processes are regarded as prototype mechanisms for pattern formation in living systems. Though suspected in many aspects of morphogenetic development, pure RD patterns have not yet been demonstrated in living organisms. The first observations of an autonomous development of stationary chemical patterns were made in the early 1990s. In this Account, we discuss the recent developments for producing stationary pH RD patterns in open spatial reactors. The theoretical analysis of the early experiments anticipated the possibility of finding Turing patterns in a wide range of oscillatory reactions if one could control the kinetic and diffusional rate of some key species. However, no experimentally effective method to produce stationary Turing patterns was attained before 2009, and the number of systems stagnated at two until then. The two precursor reaction systems benefited from unplanned favorable chemical properties of the RD media. Theoretical studies point out that appropriate diffusion rate differences are necessary to produce stationary patterns since a competition between an effective short distance self-activation and a long distance inhibitory process is required. This differential diffusion would naturally lead to differential exchange rates between the RD system and its feed environment, an aspect somewhat overlooked in theoretical and in primal experimental approaches.

中文翻译：

---

在pH自活化系统中设计平稳的反应-扩散模式

自从阿兰·图灵（Alan Turing）1952年的开创性工作以来，反应扩散（RD）过程被视为生物系统中模式形成的原型机制。尽管在形态发生发展的许多方面都令人怀疑，但纯RD模式尚未在活生物体中得到证实。1990年代初首次观察到固定化学模式的自主发展。在此报告中，我们讨论了在开放空间反应堆中生产固定pH RD模式的最新进展。早期实验的理论分析预期，如果可以控制某些关键物种的动力学和扩散速率，则有可能在广泛的振荡反应中找到图灵模式。但是，在2009年之前，没有获得产生固定图灵图案的实验有效方法，到那时为止，系统数量停滞在两个。这两种前体反应系统受益于RD介质的计划外有利化学性质。理论研究指出，由于需要有效的短距离自激活和长距离抑制过程之间的竞争，因此适当的扩散速率差异对于产生平稳模式是必要的。这种差异性扩散自然会导致RD系统与其进料环境之间的汇率差异，这在理论和原始实验方法中都被忽略了。理论研究指出，由于需要有效的短距离自激活和长距离抑制过程之间的竞争，因此适当的扩散速率差异对于产生平稳模式是必要的。这种差异性扩散自然会导致RD系统与其进料环境之间的汇率差异，这在理论和原始实验方法中都被忽略了。理论研究指出，由于需要有效的短距离自激活和长距离抑制过程之间的竞争，因此适当的扩散速率差异对于产生平稳模式是必要的。这种差异性扩散自然会导致RD系统与其进料环境之间的差异汇率，这在理论和原始实验方法中都被忽略了。