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Incremental sheet forming (ISF), a promising and flexible forming method, is generally restricted by the unsatisfied geometric deviation for industrial applications; therefore, effective control and accurate prediction of geometric deviation in ISF are essential for quality improvement. However, the geometric deviation in ISF is extremely sensitive to the geometric shape, toolpath, and process parameters, which is challenging to predict and control. In this study, the comprehensive geometric-related mechanisms in ISF were analyzed, including springback after local bending of the bent and contact zones, and the elastic deflection of the inclined wall, particularly the associated deformation in the weak-stiffness region. Through a creative equivalent mapping method for calculating the elastic deflection of complex structures and modeling the bending moment distribution in different zones, an analytical model was developed to accurately and universally predict the geometric deviations of parts by ISF. Based on the results of the experiments and comparative studies using a response surface model, the proposed model provided superior capability for predicting the geometric accuracies of parts made using ISF with different sheet materials, process parameters, and geometric shapes, even for complex parts with non-axisymmetric structures and stepped features. The geometric-related mechanisms, forming characteristics, and influences of crucial parameters in ISF are discussed by adopting an analytical model combined with numerical simulations, demonstrating that the elastic deflection on the inclined wall, particularly the associated deformation in the weak-stiffness region, plays a primary role in the geometric deviation of complex parts compared with other geometric-related mechanisms. [Display omitted] • Investigated comprehensive geometric-related mechanisms including the springback and elastic deflection during ISF. • Developed equivalent mapping method for calculating elastic deflection and analytical model of overall geometric deviation. • Validated proposed model with different geometric shapes, materials and process parameters. • Evaluated influences of crucial parameters and related mechanisms on geometric deviation. [ABSTRACT FROM AUTHOR]

Gossypol is a poisonous substance in cottonseed which seriously harms the internal organs, blood vessels, nerves, and reproductive systems of organisms. Therefore, detecting gossypol is of great significance in the field of food safety. This manuscript constructs a novel target-oriented gossypol fluorescence probe based on the energy competition absorption mechanism. The probe is a zinc-based metal organic framework material (Zn-MOF) with blue fluorescence, which can achieve rapid and sensitive detection of gossypol through fluorescence "turn-off" effect. It has the advantages of low detection limit (16.6 nM), ultra-fast response time (8 s), and favorable selectivity. Interestingly, this probe can be reused and the fluorescence can still be recovered after five cycles when detecting gossypol. In addition, the application of the fluorescent probe in cottonseed oil and fetal bovine serum is reliable, with the recovery of 99.35%–101.5% and the relative standard deviation of less than 2.72%. These results indicate that the developed sensor has prominent application potential in the field of food and biological detection. [ABSTRACT FROM AUTHOR]

Abstract Incremental sheet forming (ISF) is recognized as an advanced forming process which is highly flexible in cost-effectively producing small batched sheet metal parts. The forming force is dramatically reduced due to the local deformation and successive forming characteristics compared with traditional stamping process, and has vital impact on forming quality. It may however, be noted, that the forming force prediction models widely used are empirical ones, which needs further improvement for wider applicability. Besides, the force fluctuation in ISF has impact on the geometric accuracy, which has been less studied so far. In the present work, the analytical models for predicting the forming force for single-pass single point incremental forming (SPIF), multi-pass incremental forming (MPIF) and incremental hole flanging (IHF) processes are developed based on the new analytical models used to calculate the contact area and the through-thickness stress. A series of experiments of typical sheet metal parts in different geometries for different materials with varied process parameters including wall angle, step depth, tool radius and sheet metal thickness are used to validate the proposed analytical models. The new prediction models are proved to calculate the forming force and force components along the axial, tangential and radial directions with high accuracy for SPIF, MPISF and IHF processes. Moreover, the mechanism of force fluctuation is also investigated, and it's proved that the force fluctuation is caused by varied elastic deflection of the deforming sheet metal. Highlights • Developed analytical models to predict forming force & its components for typical ISF processes. • Developed new methods to calculate contact area and through-thickness stress. • Verified the novelties of analytical force prediction models through series of experiments. • Investigated the mechanism of forming force fluctuation during ISF and proved the root cause. [ABSTRACT FROM AUTHOR]

As the global consumption of lithium-ion batteries increased dramatically, recycling spent lithium-ion batteries became an urgent task, which is vital to alleviate resource shortages and maintain sustainable development. In this study, a strategy for preferential extraction of lithium from spent LiCoO 2 (LCO) cathodes by chlorination roasting combined with water leaching was proposed, along with the regeneration of LCO cathodes with materials recycled from spent LCO. Calcium chloride (CaCl 2) was selected for chlorination, and roasting temperature, dosage of CaCl 2 , and roasting time were optimized systematically. In this process, lithium was converted into water-soluble LiCl under a low chlorination atmosphere, the relatively stable Co-O octahedral structure was maintained in the solid phase, and preferential extraction of lithium was completed by subsequent water-leaching. The experimental results showed that 99.49% of Li was selectively recovered as LiCl which was further recovered as battery-grade Li 2 CO 3 , and 98.12% of Co was recovered in the form of Co 3 O 4. Regenerated LCO cathodes (r-LCO) from recovered Li 2 CO 3 and Co 3 O 4 , exhibited excellent electrochemical performance with a capacity of 141.2 mAh g−1 at 1 C and a high-capacity retention of 91.8% after 100 cycles. [Display omitted] • Preferential lithium extraction from spent LCO and regeneration LCO were proposed. • Li was converted to LiCl for preferential extraction and Co was recovered as Co 3 O 4. • The extraction rates of Li and Co were 99.49% and 98.12%, respectively. • Regenerated LCO exhibited excellent electrochemical performance. [ABSTRACT FROM AUTHOR]