Shaanxi University of Science & Technology

Laser induced breakdown spectroscopy (LIBS) has become an important analytical tool for extracting cultural relic information in the archaeological field because of its rapid analysis and micro damage. In this study, random forest (RF) and LIBS method were used to quantitatively analyze the brightness and identify the source of white porcelain in Xi'an. Firstly, the brightness of white porcelain fragments is measured, and the spectral brightness of white porcelain samples was analyzed quantitatively by LIBS platform. D2nd-VIM-RF calibration model was established for multi-element quantification, achieving excellent prediction performance with an R²_CV of 0.9814 and an RPD of 4.6. Secondly, an RF classification model was developed to distinguish two types of white porcelain from Xi'an. Based on spectral data, the model was optimized using MSC-WT preprocessing and VIM-SPA variable selection, resulting in the MSC-WT-VIM-SPA-RF classification model. It achieved a sensitivity of 0.9670, specificity of 0.9438, and overall accuracy of 0.9600, significantly enhancing classification reliability. To optimize both the predictive capability and explanatory power of the model, quantitative brightness was incorporated as an auxiliary variable alongside LIBS spectra. Brightness reflects surface features such as glaze quality and microstructure, which are closely associated with raw material composition and firing techniques critical factors for distinguishing porcelain types. This study underscores the significant potential of combining LIBS and RF technology for rapid, minimally invasive analysis of ancient white porcelain, offering valuable insights into the classification, identification, and quantitative analysis of historical ceramics.

Multiplex nucleic acid amplification is essential for saving sample material and reducing reagent consumption. Common detection methods usually involve the use of fluorogenic probes that emit at different wavelengths, and the number of fluorescent channels often limits the degree of multiplexing. Photobleaching enables multiplex detection under a single excitation wavelength and emission wavelength, thereby overcoming the limitations inherent in traditional fluorescence detection methods. However, most reports rely on organic fluorescent dyes, and photostable quantum dots have often been neglected in photobleaching-based multiplexing. Herein, we present a fast and simple technique that enables monochrome multiplexed detection in loop-mediated isothermal amplification using quantum dot-525 nm and FAM fluorescent labels with the same green emission. This technique involves the inclusion of two fluorescent label primers and a quencher probe. If the target is present, the primer will emit the same fluorescent signal. However, with unamplified primers, the fluorescence is quenched. The two fluorescent signals exhibit different fluorescence changes during photobleaching, thereby distinguishing between different products. We successfully applied this method to loop-mediated isothermal amplification for S. aureus and L. monocytogenes. The method demonstrates high sensitivity and specificity and can be analyzed in complex biological samples. Additionally, a 2-plex loop-mediated isothermal amplification reaction in a single color channel was demonstrated. In the future, the color of quantum dots and the melting temperature of extension primers can also serve as independent parameters for detection. The integration of these two parameters may further improve the degree of multiplexing. This method could also be applied to rapid field-based screening.

Thick electrodes with high active material loading are considered ideal for Li-ion batteries, yet they suffer from intrinsic challenges of sluggish ion transport kinetics and poor mechanical stability. Although carbon-based scaffolds can enhance electron conductivity in conventional thick electrodes, their practical applications are hindered by complex fabrication processes, inefficient Li⁺ transport and high costs. This study constructed a three-dimensional conductive fibrous network through the synergistic integration of chitosan and sodium carboxymethyl cellulose, enabling the fabrication of high-loading self-supporting LiFePO₄ flexible paper electrodes. The fully aqueous processing eliminates conventional PVDF binders and metal current collectors, and the vacuum filtration-driven ordered deposition of active materials achieves precise control over interconnected porous structures and chemical compatibility. The unique gradient-layered porous architecture and continuous electron pathways significantly optimize ion/electron transport kinetics. The flexible paper electrode with a 20 mg cm^-2 LiFePO₄ mass loading delivers a high specific capacity of 165 mAh g^-1 at 0.1C, achieving a remarkable volumetric energy density of 578 Wh/L at a high LiFePO₄ mass loading of 40 mg cm^-2. This research enables the advancement an eco-friendly approach for developing high-energy-density and low-environmental-impact energy storage technologies.