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摘要： Hydrothermal reactions of 2,4,6-tris(2-pyrimidinyl)-1,3,5-triazine (TPymT) with zinc chloride (ZnCl₂) and with cadmium chloride (CdCl₂) yielded two distinct complexes with divergent ligand reactivity. The reaction with ZnCl₂ induced complete hydrolysis of TPymT to generate the pyrimidine-2-carboxylate anion (2-PmC), affording the 1D zinc coordination polymer [ZnCl(μ-2-PmC)]_n (1) in a good yield of 87.8%. In contrast, the analogous hydrothermal reaction with CdCl₂ proceeded without ligand hydrolysis, leading to the formation of the mononuclear cadmium complex [CdCl₂(TPymT)(H₂O)]·3H₂O (2). Complex 1 was comprehensively characterized by elemental analysis, thermogravimetric analysis (TGA), Fourier-transform infrared (FT-IR) spectroscopy, single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), and Hirshfeld surface analysis. Complex 2 was characterize via SCXRD, PXRD and Hirshfeld surface analysis. Solid-state UV–Vis absorption and photoluminescent properties of 1 were further investigated to evaluate its potential optical application prospects. Complementary theoretical calculations were performed to rationalize the metal-dependent TPymT hydrolysis behavior. The synergistic effect of the Zn(II) system's lower molecular stability (narrower HOMO-LUMO gap) and higher electrophilicity promotes ligand dissociation and TPymT hydrolysis. In contrast, Cd(II) exhibits hydrolytic resistance due to its strong nucleophilicity and negative condensed dual descriptor (CDD) value, which collectively stabilize the ligand-metal coordination framework. This work provides valuable insights into the metal-regulated hydrolysis reactivity of TPymT and enriches the coordination chemistry of triazine-pyrimidine hybrid ligands.

关键词： Energy harvesting   Voltage step-up   Boost converter   Charge pump   Thermoelectric   Impedance matching   Maximum power tracking   Power extraction circuit  

摘要：

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  Achieved voltage step-up from 1 mV input to 0.85 V using a boost converter.
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  Demonstrated parasitic impedance matching outperforms traditional matching for 1 mV input.
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  Demonstrated output power above 8 µW from 1 mV input.
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  Promotes wider application of low-cost, reliable thermoelectric modules.

关键词： Analysis model   Signal recovery   ℓ1/ℓ2-regularized minimization   ℓ1/ℓ2norm ratio  

摘要： Currently, in sparse representation of signals, the synthesis model has been extensively studied, while the analysis model receives comparatively less attention. Regarding the sparsity metric, ℓ₁/ℓ₂ norm ratio not only has a sharp approximation to ℓ₀-norm, but also satisfies the scale invariance property inherent to ℓ₀-norm. Motivated by these, this work introduces an analysis model based ℓ₁/ℓ₂-regularized minimization for signal recovery, and conducts theoretical analysis on it under reasonable assumptions that the measurement matrix is full row rank and the observed vector is nonzero. First, under a sufficient condition related to the regularization parameter, we prove that its global minimizer cannot be zero and its solution set is nonempty. Then, we derive an upper bound for any local minimizer of it in terms of ℓ₂-norm. Given that it is nontrivial to directly solve this problem, we relax it by the penalty technique, and provide theoretical analysis for the relaxed version under the aforesaid assumptions, including the nonzero-ness of the global minimizer and the solution existence with the same sufficient condition. Similarly, an upper bound for any local minimizer in terms of ℓ₂-norm is derived. An algorithm for solving the relaxed version is proposed by leveraging alternating minimization and difference-of-convex algorithm, its complexity analysis is also given. Our algorithm is tested via extensive experiments involving numerical examples of one dimensional signal recovery and applications in several image restoration tasks, showing its superiority and competitiveness over some rivals.

摘要： Cu-doped Co–ferrite composites (Cu_xCo_1-xFe₂O₄, x = 0.1, 0.2, and 0.3) are successfully synthesized via a simple co-precipitation method and evaluated as anode materials for lithium-ion batteries (LIBs). Among the prepared samples, the composite with x = 0.2 demonstrates the best electrochemical performance, delivering a high reversible capacity of 784 mAh g⁻¹ at a current density of 100 mA g⁻¹ after 100 charge–discharge cycles. By contrast, the capacities of the x = 0.1 and x = 0.3 composites decline significantly after 60 cycles. Comprehensive material characterizations reveal that the superior performance of the Cu_0.2Co_0.8Fe₂O₄ composite can be attributed to its optimal phase composition, enhanced nanoparticle interconnectivity, and the presence of abundant oxygen vacancies, which collectively improve the electronic conductivity. The results underscore the importance of the spinel structure, the Cu-to-Co ratio, and the resulting microstructural features in achieving a high surface area conducive to efficient ion transport. This work not only highlights the potential of Cu-doped Co–ferrites as high-performance LIB anodes but also introduces a straightforward and scalable chemical synthesis route for their fabrication.

关键词： 成人   节段性膜性肾病   膜性肾病  

摘要： 节段性膜性肾病(segmental membranous nephropathy, sMN)是儿童好发的一种特殊类型的肾脏疾病,通常表现为肾小球基底膜外侧、上皮下免疫复合物节段性分布,而非全肾受累。sMN并不表现为典型肾病综合征,通常PLA2R、THSD7A阴性,常合并其他肾脏疾病,临床诊断需首先排除继发性因素。现报道1例成人节段性膜性肾病病例。1 病例介绍患者男,20岁,主因“体检发现蛋白尿20余天”入院。

关键词： Non-destructive testing   Power engineering steels   Eddy current   Coil impedance  

摘要： Ferritic–martensitic P91 steel is widely used in high-temperature power plant components due to its excellent creep resistance and mechanical stability. However, long-term service exposure and improper heat treatment can lead to progressive microstructural degradation, resulting in a reduction of mechanical properties and component lifetime. Reliable, non-destructive methods capable of detecting such microstructural changes are therefore essential for condition monitoring and life assessment. In this study, the influence of controlled heat treatment at temperatures ranging from 200 °C to 600 °C on the eddy current (EC) response of P91 steel was investigated. Eddy current measurements were performed over a range of probe operating frequencies, and changes in resistance and reactance components were quantitatively analyzed. The EC results were correlated with detailed microstructural observations, revealing a strong relationship between electromagnetic response and recovery and tempering phenomena, including dislocation density reduction, martensite lath degradation, and carbide coarsening. The findings demonstrate that eddy current testing is highly sensitive to thermally induced microstructural evolution in P91 steel and shows significant potential as a non-destructive tool for assessing thermal exposure and material degradation in power plant components.

关键词： Solubility   Amino acid   Ionic liquid   NRTL  

摘要： A comprehensive understanding of the solubility of amino acids across different solvents and environmental conditions enables improved extraction and purification strategies, also providing insight into molecular interactions and supporting the development of more accurate modelling approaches. In this work, the solubility of seven collagen-forming amino acids (glycine, β-alanine, l-proline, trans-4‑hydroxy-l-proline, l-glutamic acid, l-aspartic acid and l-arginine) in the ionic liquid 1-ethyl-3-methylimidazolium propionate, and its mixture with water at equal mass proportions, was measured at temperatures ranging from 298.15 K to 328.15 K and atmospheric pressure. Compositions were determined from density–composition calibration curves. Acidic amino acids showed the highest solubility in the pure ionic liquid, followed by proline and trans-4‑hydroxy-l-proline, key amino acids for collagen stabilization. Using water as a co-solvent increased the solubility on a mass basis of l-proline and β-alanine but decreased that of the other amino acids. Solubility increased with temperature across all systems. A comparison with other imidazolium salts suggests that increasing the ionic liquid’s hydrophobicity, whether by elongating the alkyl chain of the anion or cation, leads to a decrease in solubility. The van’t Hoff equation was found to accurately describe solubility across the studied temperature range and was used to calculate apparent thermodynamic properties of dissolution. All the apparent properties were found to be positive, indicating and endothermic and entropy-favoured process. Finally, the experimental data were correlated using the Non-Random Two-Liquid (NRTL) model.

关键词： Gastric cancer   Migration and infiltration   SPIN1   Slug   Claudin-1  

摘要： Metastases are responsible for over 90% of the deaths in patients with gastric cancer (GC). Our previous study revealed that SPIN1 promotes the invasion and metastasis of GC; however, the underlying mechanism remains unclear.

关键词： Eye-safe wavelength   High power fiber laser   Laser oscillator   Tm fiber laser  

摘要： We report a continuous-wave thulium (Tm)-doped fiber laser oscillator with >1 kW output power operating at 1940 nm under the optimized cooling condition. Using a water calorimetry method, the temperature increases and its impact on output power were experimentally investigated, confirming good agreement with theoretical predictions. To mitigate thermal effects on laser performance, a bi-directional pumping configuration was implemented, theoretically reducing the maximum Tm fiber temperature by ∼40% compared to forward pumping. Under the optimized cooling condition, the Tm fiber laser yielded a maximum output power of 1032 W for an incident pump power of 1785 W, corresponding to a slope efficiency of 58.5%. A near-diffraction-limited beam quality was maintained at all power levels, along with excellent output stability.