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  “概念”在基础研究中是一个很有用的抽象名词,它可以使不同地方,使用不同语言的科学家很容易根据同一个概念联想到相同的事物。“概念”其中一种解释是人对事物本质的认识,是逻辑思维的最基本单元和形式。概念是人们用于认识和掌握自然现象的概括和总结,是认识过程中的阶段。思维要正确地反映客观现实,概念就必须是主观性与客观性、特殊性与普遍性、抽象性与具体性的辩证统一。概念是灵活的、往返流动的和相互转化的,是富有具体内容的、有不同规定的、多样性的统一。科学认识的主要成果就是形成和发展概念,概念越深刻、越正确,就越完全地反映客观现实。概念虽然简洁好用,但是它的人为概括也带来了困扰,那就是概念的不完整性和理解上的偏差。     
   写这一段话的原因并非是出于卖弄,而是我们在如何理解和运用“自组装、自组织、超分子、超分子组装”等概念及涉及到其相互之间联系与区别的认识上遇到了对这些概念理解上的困惑。我们期望用这些概念来描述我们目前开展的研究工作及发现的有趣现象,但是相关用词准确、严谨吗?其实对于同一个自然现象,观察的视角不同(比如不同学科),出发点不同(比如不同观察者),给出的理解和认识也会不同(比如不同背景),所谓公说公有理,婆说婆有理。然而,当这些词汇被从一个审视的角度看待时,认识上的偏差可能会产生意想不到的后果。     
   尽管如此,认识上的差异并不妨碍我们研究构筑基元在组分间相互作用影响下形成的有序分子聚集体的结构、性质、动态过程和功能化应用。同时,我们也可以在发展自己的研究体系过程深化对这些概念的理解,提高用合理而又贴切的概念刻画我们所得到的研究结果的本质的能力。     
   下面是一些搜索到的相关概念的解释,你能明确说明它们之间的联系与区别吗?

Self-assembly: It is a term used to describe processes in which a disordered system of pre-existing components forms an organized structure or pattern as a consequence of specific, local interactions among the components themselves, without external direction. When the constitutive components are molecules, the process is termed molecular self-assembly. Self-assembly can be classified as either static or dynamic. In static self-assembly, the ordered state forms as a system approaches equilibrium, reducing its free energy. However in dynamic self-assembly, patterns of pre-existing components organized by specific local interactions are not commonly described as "self-assembled" by scientists in the associated disciplines. These structures are better described as "self-organized".

---From Wikipedia, the free encyclopedia

Self-organization: It is a nonequilibrium process where self-assembly is a spontaneous process that leads toward equilibrium. Self-assembly requires components to remain essentially unchanged throughout the process. Besides the thermodynamic difference between the two, there is also a difference in formation. The first difference is what “encodes the global order of the whole” in self-assembly where as in self-organization these initial encodings are not necessary. Another slight contrast refers to the minimum number of units needed to make an order. Self-organization appears to have a minimum number of units where as self-assembly does not. These terms are becoming more necessary as more is learned about natural selection. Eventually, these patterns may form one theory regarding the pattern formation in nature.
Self-organization and self-assembly are regularly used interchangeably. As complex system science becomes more popular though, there is a higher need to clearly distinguish the differences between the two mechanisms to understand their significance in physical and biological systems. Both processes explain how collective order is developed from “dynamic small-scale interactions”.

---From Wikipedia, the free encyclopedia

Molecular self-assembly: It is the process by which molecules adopt a defined arrangement without guidance or management from an outside source. There are two types of self-assembly, intramolecular self-assembly and intermolecular self-assembly. Most often the term molecular self-assembly refers to intermolecular self-assembly, while the intramolecular analog is more commonly called folding. Molecular self-assembly is a key concept in supramolecular chemistry since assembly of the molecules is directed through noncovalent interactions (e.g., hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, π-π interactions, and/or electrostatic) as well as electromagnetic interactions. Common examples include the formation of micelles, vesicles, liquid crystal phases, and Langmuir monolayers by surfactant molecules. Further examples of supramolecular assemblies demonstrate that a variety of different shapes and sizes can be obtained using molecular self-assembly.

---From Wikipedia, the free encyclopedia

Supramolecular chemistry: It refers to the area of chemistry beyond the molecules and focuses on the chemical systems made up of a discrete number of assembled molecular subunits or components. The forces responsible for the spatial organization may vary from weak (intermolecular forces, electrostatic or hydrogen bonding) to strong (covalent bonding), provided that the degree of electronic coupling between the molecular component remains small with respect to relevant energy parameters of the component. While traditional chemistry focuses on the covalent bond, supramolecular chemistry examines the weaker and reversible noncovalent interactions between molecules. These forces include hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, pi-pi interactions and electrostatic effects. Important concepts that have been demonstrated by supramolecular chemistry include molecular self-assembly, folding, molecular recognition, host-guest chemistry, mechanically-interlocked molecular architectures, and dynamic covalent chemistry. The study of non-covalent interactions is crucial to understanding many biological processes from cell structure to vision that rely on these forces for structure and function. Biological systems are often the inspiration for supramolecular research.

---From Wikipedia, the free encyclopedia

Supramolecular assembly or "supermolecule": It is a well defined complex of molecules held together by noncovalent bonds. While a supramolecular assembly can be simply composed of two molecules (e.g., a DNA double helix or an inclusion compound), it is more often used to denote larger complexes of molecules that form sphere-, rod-, or sheet-like species. The dimensions of supramolecular assemblies can range from nanometers to micrometers. Thus they allow access to nanoscale objects using a bottom-up approach in far fewer steps than a single molecule of similar dimensions. The process by which a supramolecular assembly forms is called molecular self-assembly. Some try to distinguish self-assembly as the process by which individual molecules form the defined aggregate. Self-organization, then, is the process by which those aggregates create higher-order structures. This can become useful when talking about liquid crystals and block copolymers.

---From Wikipedia, the free encyclopedia

 

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