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In precision machine assembly process, the product quality is not only dependent on the tolerance design, but also on the assurance of the assembly process planning. Therefore, there is a need to develop a mathematical analysis method to predict and control the variation in an assembly process. In this paper, to improve assembly precision and finally improve assembly quality stability for machining products, a mechanical assembly accuracy prediction model based on a state space equation is put forward. In this approach, fuzzy analytical hierarchy process (FAHP) is used to identify the key factor affecting the product quality. With the help of current variation of assembling process, the state space equation is used to build the variation propagation model of a mechanical assembly system, predict the influence law of machine precision, and guarantee the machine assembly precision within the boundary. Finally, the validity is verified by using the application of the small six-axis precision machine tool.

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The non-isothermal crystallization kinetics of double-crystallizable poly(ethylene glycol)–poly(l-lactide) diblock copolymer (PEG-PLLA) and poly(ethylene glycol) homopolymer (PEG) were studied using the fast cooling rate provided by a Fast-Scan Chip-Calorimeter (FSC). The experimental data were analyzed by the Ozawa method and the Kissinger equation. Additionally, the total crystallization rate was represented by crystallization half time t1/2. The Ozawa method is a perfect success because secondary crystallization is inhibited by using fast cooling rate. The first crystallized PLLA block provides nucleation sites for the crystallization of PEG block and thus promotes the crystallization of the PEG block, which can be regarded as heterogeneous nucleation to a certain extent, while the method of the PEG block and PLLA block crystallized together corresponds to a one-dimensional growth, which reflects that there is a certain separation between the crystallization regions of the PLLA block and PEG block. Although crystallization of the PLLA block provides heterogeneous nucleation conditions for PEG block to a certain extent, it does not shorten the time of the whole crystallization process because of the complexity of the whole crystallization process including nucleation and growth.

Lithium‐ion batteries (LIBs) are one of the most widely used technologies for various applications. However, polyolefin separators can hardly meet the needs of the development of LIBs due to the poor heat shrinkage and bad wettability with the electrolyte. Herein, a cellulose acetate (CA)‐based separator is developed by blending with cellulose nanocrystals (CNCs) using a simple reversible acetylation process. This separator exhibits inherent thermal stability and improved ionic conductivity due to the finger‐like and sponge‐like porous structure. Moreover, the discharge capacity of the separator with a CNC loading of 3% remains at 132.9 mA h g−1 when the rate reverts to 0.2 C and the capacity retention reaches 89.5% after 50 cycles. Therefore, the obtained CA‐based separators can be a competitive candidate for high‐performance LIBs and point the way to sustainable development.