Global existence and bounds for blow‐up time in a class of nonlinear pseudo‐parabolic equations with a memory term

In this article, we consider the initial boundary value problem for a class of nonlinear pseudo‐parabolic equations with a memory term: Under suitable assumptions, we obtain the local and global existence of the solution by Galerkin method. We prove finite‐time blow‐up of the solution for initial data at arbitrary energy level and obtain upper bounds for blow‐up time by using the concavity method. In addition, by means of differential inequality technique, we obtain a lower bound for blow‐up time of the solution if blow‐up occurs.     

Two Optimal Value Functions in Parametric Conic Linear Programming

Journal of Optimization Theory and Applications - We consider the conic linear program given by a closed convex cone in an Euclidean space and a matrix, where vector on the right-hand side of the...     

Periodic quenching modulated quantum phase transitions in transverse XY spin-chains

The European Physical Journal D - Bent crystals are a compact and versatile tool to manipulate ultra-relativistic particle beams in accelerators. Indeed, the unrivaled steering power achievable...     

Two new xanthones from the pericarp of Garcinia mangostana

Two new xanthones, designated garcimangosxanthone F (1) and garcimangosxanthone G (2), were isolated from the EtOAc-soluble fraction of ethanolic extract from the pericarp of Garcinia mangostana. Their structures were established as 1,6,7-trihydroxy-5-(3-methylbut-2-enyl)-8-(3-hydroxy-3-methylbutyl)-6′,6′-dimethylpyrano[2′,3′:3,2]xanthone and 1,6,7-trihydroxy-5-(3-methylbut-2-enyl)-8-(3-hydroxy-3-methylbutyl)-6′,6′-dimethyl-4′,5′-dihydropyrano[2′,3′:3,2]xanthone, respectively, on the basis of their 1D, 2D NMR and MS data interpretation.     

Development of a method using high‐performance liquid chromatographic fingerprint and multi‐ingredients quantitative analysis for the quality control of Yangxinshi Pian

A simple and reliable method of high‐performance liquid chromatography with diode array detection method was developed for fingerprint analysis and simultaneous determination of six compounds including puerarin, salvianolic acid B, berberine hydrochloride, palmatine chloride, dehydrocorydaline, and icariin in the Chinese medicine preparation Yangxinshi Pian. The separation was performed on an Agilent Eclipse XDB‐C₁₈ reserved‐phase column (250 mm × 4.6mm I.D., 5 μm) using gradient elution with 50 mmol/L monopotassium phosphate aqueous solution and methanol as mobile phase at a flow rate of 1.0 mL/min. The column operating temperature was set at 30°C, and the detection wavelength was 280 nm. The method was validated by linearity, precision, accuracy, stability, and recovery. For fingerprint analysis, 25 peaks were selected as the common peaks, and four kinds of similarities including cosine similarity (S), ratio of similarity (S′), projection content similarity (C), and content similarity (P) were applied to evaluate the quality consistency of different batches of Yangxinshi Pian. The results showed that the developed method was an efficient tool for quality evaluation of Yangxinshi Pian.     

Application of chromatography technology in the separation of active alkaloids from Hypecoum leptocarpum and their inhibitory effect on fatty acid synthase

A method that involved the combination of pH‐zone‐refining counter‐current chromatography and semipreparative reversed‐phase liquid chromatography has been established for the preparative separation of alkaloids from Hypecoum leptocarpum. From 1.2 g of crude sample, 31 mg N‐feruloyltyramine, 27 mg oxohydrastinine, 47 mg hydroprotopine, 25 mg leptopidine, and 18 mg hypecocarpine have been obtained. The structure of the new compound, hypecocarpine, is confirmed based on the analysis of spectroscopic data, including NMR, UV, and IR spectroscopy and positive electrospray ionization mass spectrometry. The known chemical structures were characterized on the basis of ¹H and ¹³C NMR spectroscopy. The purities of the five alkaloids are all over 92.7% as determined by high‐performance liquid chromatography. The alkaloids’ cytotoxicity in breast cancer cells is assessed by using a Cell Counting Kit assay and their inhibitory effect on fatty acid synthase expression is assessed by a Western blot assay. These results suggest that leptopidine could suppress growth and induce cytotoxicity in breast cancer cells and that the cytotoxicity of leptopidine may be related to its inhibitory effect on fatty acid synthase expression.     

Comprehensive H2O Molecules Regulation via Deep Eutectic Solvents for Ultra-Stable Zinc Metal Anode

The corrosion, parasitic reactions, and aggravated dendrite growth severely restrict development of aqueous Zn metal batteries. Here, we report a novel strategy to break the hydrogen bond network between water molecules and construct the Zn(TFSI)₂-sulfolane-H₂O deep eutectic solvents. This strategy cuts off the transfer of protons/hydroxides and inhibits the activity of H₂O, as reflected in a much lower freezing point (<−80 °C), a significantly larger electrochemical stable window (>3 V), and suppressed evaporative water from electrolytes. Stable Zn plating/stripping for over 9600 h was obtained. Based on experimental characterizations and theoretical simulations, it has been proved that sulfolane can effectively regulate solvation shell and simultaneously build the multifunctional Zn-electrolyte interface. Moreover, the multi-layer homemade modular cell and 1.32 Ah pouch cell further confirm its prospect for practical application.     

Coordinating the Edge Defects of Bismuth with Sulfur for Enhanced CO2 Electroreduction to Formate

Bismuth-based materials have been recognized as promising catalysts for the electrocatalytic CO₂ reduction reaction (ECO₂RR). However, they show poor selectivity due to competing hydrogen evolution reaction (HER). In this study, we have developed an edge defect modulation strategy for Bi by coordinating the edge defects of bismuth (Bi) with sulfur, to promote ECO₂RR selectivity and inhibit the competing HER. The prepared catalysts demonstrate excellent product selectivity, with a high HCOO⁻ Faraday efficiency of ≈95 % and an HCOO⁻ partial current of ≈250 mA cm⁻² under alkaline electrolytes. Density function theory calculations reveal that sulfur tends to bind to the Bi edge defects, reducing the coordination-unsaturated Bi sites (*H adsorption sites), and regulating the charge states of neighboring Bi sites to improve *OCHO adsorption. This work deepens our understanding of ECO₂RR mechanism on bismuth-based catalysts, guiding for the design of advanced ECO₂RR catalysts.     

An Unlocked Two-Dimensional Conductive Zn-MOF on Polymeric Carbon Nitride for Photocatalytic H2O2 Production

Developing highly efficient catalytic sites for O₂ reduction to H₂O₂, while ensuring the fast injection of energetic electrons into these sites, is crucial for artificial H₂O₂ photosynthesis but remains challenging. Herein, we report a strongly coupled hybrid photocatalyst comprising polymeric carbon nitride (CN) and a two-dimensional conductive Zn-containing metal–organic framework (Zn-MOF) (denoted as CN/Zn-MOF(lc)/400; lc, low crystallinity; 400, annealing temperature in °C), in which the catalytic capability of Zn-MOF(lc) for H₂O₂ production is unlocked by the annealing-induced effects. As revealed by experimental and theoretical calculation results, the Zn sites coordinated to four O (Zn-O₄) in Zn-MOF(lc) are thermally activated to a relatively electron-rich state due to the annealing-induced local structure shrinkage, which favors the formation of a key *OOH intermediate of 2e⁻ O₂ reduction on these sites. Moreover, the annealing treatment facilitates the photoelectron migration from the CN photocatalyst to the Zn-MOF(lc) catalytic unit. As a result, the optimized catalyst exhibits dramatically enhanced H₂O₂ production activity and excellent stability under visible light irradiation.