Utilizing X-ray diffraction in conjunction with competitive adaptive reweighted sampling (CARS) and principal component analysis for the discrimination of medicinal pearl powder and nacre powder.

Nacre powder, often utilized to counterfeit medicinal pearl powder due to their similar chemical composition and appearance, poses a challenge in product authentication. This study introduces a rapid and efficient method for distinguishing between medicinal pearl powder and nacre powder using X-ray diffraction in conjunction with principal component analysis (PCA). The X-ray diffraction pattern underwent preprocessing techniques including smoothing denoising (Savitzky-Golay filter, 5-point) and second-order derivative analysis. Subsequently, PCA was employed for dimensionality reduction modeling. The CARS method was applied to select optimal variables for model refinement, determining the data preprocessing approach and key modeling variables. This method demonstrates the capability to accurately differentiate between pearl powder, nacre powder, and even counterfeit samples containing up to 90% pearl powder. With a high accuracy rate, swift operational speed, and potential for automation, this approach shows promise for practical implementation in the realm of pearl powder quality control.

Nickel-Ion Activating Discarded COVID-19 Medical Surgical Masks for Forming Carbon-Nickel Composite Nanowires and Using as a High-Performance Lithium Battery Anode.

With the prevalence of COVID-19, wearing medical surgical masks has become a requisite measure to protect against the invasion of the virus. Therefore, a huge amount of discarded medical surgical masks will be produced, which will become a potential hazard to pollute the environment and endanger the health of organisms without our awareness. Herein, a green and cost-effective way for the reasonable disposal of waste masks becomes necessary. In this work, we realized the transformation from waste medical surgical masks into high-quality carbon-nickel composite nanowires, which not only benefit the protection of the environment and ecosystem but also contribute to the realization of economic value. The obtained composite carbon-based materials demonstrate 70 S m-1 conductivity, 5.2 nm average pore diameters, 234 m2 g-1 surface areas, and proper graphitization degree. As an anode material for lithium-ion batteries, the prepared carbon composite materials demonstrate a specific capacity of 420 mA h g-1 after 800 cycles at a current density of 0.2 A g-1. It also displays good rate performance and decent cycling stability. Therefore, this study provides an approach to converting the discarded medical surgical masks into high-quality carbon nanowire anode materials to turn waste into treasure.

Synthesis, properties and photovoltaic performance in dye-sensitized solar cells of three meso-diphenylbacteriochlorins bearing a dual-function electron-donor.

Bacteriochlorins are crucial to photosynthesis in bacteria. Studies of air-stable, meso-substituted bacteriochlorins are rare. We herein report the synthesis, properties, and photovoltaic performance of three new air-stable, meso-substituted bacteriochlorins bearing a dioctylfluorenylethyne (denoted as LS-17), a dioctylaminophenylethynylanthrylethyne (LS-43), and a diarylaminoanthrylethyne (LS-45) as the electron-donating groups. Among these LS-bacteriochlorins, LS-17 displays sharp UV-visible absorption bands whereas LS-43 and LS-45 give rise to broadened and red-shifted absorptions. Electrochemical and DFT results suggest that the first oxidation and reduction reactions of these bacteriochlorins are consistent with the formation of the cation and anion radicals, respectively. For dye-sensitized solar cell applications, photovoltaic performance of the LS-45 cell achieves an overall efficiency of 6.04% under one-sun irradiation.