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首页> 外文会议>Sugar Processing Research Conference; 20000409-20000412; Porto; PT >NEW APPROACHES TO CRYSTALLIZATION THEORIES
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NEW APPROACHES TO CRYSTALLIZATION THEORIES

机译：结晶理论的新方法

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Two fundamental crystallization theories are briefly described: The theory of the adsorption layer, which deals with the crystal surface, and the diffusion theory, which considers phenomena occurring at the crystal solution interface. Another approach is proposed based on chaos and complexity theory. The chaos and complexity theory deals with the nonreversible thermodynamics of non-equilibrium conditions. It is correlated also with the concept of entropy, which being a measure of disorder and uncertainty, becomes the cause for the creation of new patterns of mass and energy dissipation. These all being called "dissipative structures" from the 1977 chemistry Nobel laureate llya Prigogine. Apart from the different levels of concentration, viscosity, temperature, pressure, supersaturation etc. of the mother liquor, there are also the different impurities which influence sucrose crystal growth morphology, modifying the habit of the crystals. In the same strike it is highly improbable that one crystal of sugar examined in the atomic scale, will be identical to another. It has been said that snowflakes are unique and no snowflake can be identical with another. The same seems to be valid for the sugar crystals. The sugar crystals, after drying, are in equilibrium with the environment, but they bear in their surface, examined under an electron microscope, with dislocations and other irregularities of their crystal lattice the irreversibilities of their growth. The sugar crystal is an "equilibrium structure" but bears on its surface and on its inner structure the fingerprints, the history of a "dissipative structure". The sugar crystal is a frozen, immobilized, crystallized irreversible "dissipative structure". It is the 3-D configuration and materialization of a transient structure. The pulsating character and mechanism of crystallization presents similarities to the Belousov-Zhabotinski reaction. To simplify and explain better the molecular dynamic simulation of sucrose crystallization, the application of an eleven dimension model is proposed. The four forces of nature (gravity, electromagnetic, weak and strong) are in interaction during industrial crystallization. Problems of conglomerates and poor CV of continuous vacuum pans with stirrer in comparison to the discontinuous vacuum pans with stirrer are discussed and a solution for improvement is proposed based on the logic of chaos and complexity theory.
机译：简要介绍了两种基本的结晶理论：处理晶体表面的吸附层理论和考虑晶体溶液界面处发生的现象的扩散理论。根据混沌和复杂性理论提出了另一种方法。混沌和复杂性理论涉及非平衡条件的不可逆热力学。它也与熵的概念相关，熵是对无序和不确定性的一种度量，它成为创造新的质量和能量耗散模式的原因。这些都被称为1977年诺贝尔化学奖得主llya Prigogine的“耗散结构”。除了母液的浓度，粘度，温度，压力，过饱和度等不同水平外，还存在影响蔗糖晶体生长形态，改变晶体习性的不同杂质。在同一次打击中，极不可能在原子尺度上检查一个糖晶体与另一个晶体相同。有人说雪花是独一无二的，没有雪花可以与另一个雪花相同。糖晶体似乎同样有效。干燥后的糖晶体与环境处于平衡状态，但在电子显微镜下观察时，它们的表面仍带有表面位错和其他不规则性，这是其生长的不可逆性。糖晶体是“平衡结构”，但在其表面和内部结构上带有指纹，即“耗散结构”的历史。糖晶体是冷冻的，固定的，结晶的不可逆的“耗散结构”。它是瞬态结构的3D配置和实体化。脉动特性和结晶机理与Belousov-Zhabotinski反应相似。为了简化和更好地解释蔗糖结晶的分子动力学模拟，提出了一种十一维模型的应用。在工业结晶过程中，自然的四个力（重力，电磁力，弱和强）相互作用。与带搅拌器的不连续真空锅相比，讨论了带搅拌器的连续真空锅的团聚和差的CV问题，并基于混沌逻辑和复杂性理论提出了改进的解决方案。

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