During carbonisation (primary and secondary) and then graphitisation processes, any organic precursor is subjected to deep structural changes which make it evolve from an isotropic to an anisotropic material, with the extent of the anisotropy being related to the starting elemental composition, and ultimately to the graphitisability. For decades, analysing X-ray diffraction patterns has been used to evidence the related structural evolution of the material, aiming at extracting the average crystallite dimension L_a and L_c as they closely relate to the material physical properties. In particular because of the two-dimensional nature of the graphene-based crystallites which develop in the material and, upon heat-treatment, either remain so for non-graphitisable carbons or gradually convert partially or fully into three-dimensional crystals for graphitizable carbons, accurately understanding and analysing XRD patterns has always been an issue. A new approach for analysing XRD data is described, designated as "bottom-up", meanwhile introducing the concept of Basic Structural Component. A better knowledge of the overall thermally-driven structure changes which occur in the material from the coke stage to the ultimate temperature of 2800 °C is achieved, which is expected to apply to any kind of carbons, whatever their graphitisability.

中文翻译：

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关于了解碳化和石墨化机制的新见解

在碳化过程中（主要和次要的）以及随后的石墨化过程中，任何有机前体都会经历深层结构变化，从而使其从各向同性材料演化为各向异性材料，且各向异性程度与起始元素组成有关，最终与石墨化性。几十年来，通过分析X射线衍射图来证明材料的相关结构演变，旨在提取平均微晶尺寸L _a和L _c。因为它们与材料的物理特性密切相关。尤其是由于石墨烯基微晶的二维性质，这种微晶在材料中生长，并且在热处理后对于非石墨化碳仍然保留，或者逐渐或部分或全部转化为可石墨化碳的三维晶体，准确地理解和分析XRD模式一直是一个问题。描述了一种用于分析XRD数据的新方法，称为“自下而上”，同时介绍了基本结构构件的概念。可以更好地了解从焦炭阶段到最终温度2800°C的材料中发生的整体热驱动结构变化，这有望应用于任何种类的碳，无论其可石墨化性如何。