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The PUREX process is a key technology for spent fuel reprocessing, designed to selectively recover uranium and plutonium mainly through multiple chemical separation stages, minimizing high-level waste. Acetohydroxamic acid (AHA) enhances selectivity in this process but decomposes into acetic acid (HAc), which disrupts chemical equilibrium and reduces extraction efficiency. This study examines the extraction and separation of nitric acid (HNO3) and HAc using 30% tributyl phosphate in organic kerosene (TBP-OK) under various conditions. Results show that 30%TBP-OK preferentially extracts HAc over HNO3, especially in the low acid concentration range (HNO₃ < 1 mol/L, HAc < 0.2 mol/L). The selectivity coefficient drops from 3.05 in a 0.5 mol/L HNO3-0.1 mol/L HAc system to 2.18 in a 1 mol/L HNO3-0.2 mol/L HAc system. TBP forms stable 1:1 complexes with both acids, with equilibrium constants around 0.85 under typical conditions. Increasing TBP concentration enhances HNO3 extraction, while phase ratio adjustments improve HAc separation. A 16-stage countercurrent extraction simulation confirms that optimizing these factors effectively separates HNO3 and HAc, offering theoretical and technical support for refining the PUREX process.

The progression of Chronic gastritis seems to follow a pattern from chronic non-atrophic gastritis (CNAG) to chronic atrophic gastritis (CAG) to cancer, so it is particularly important to block key targets in disease progression. A gene that synthesizes secreted phospholipase A2, attracted our attention. To study whether phospholipase A2 group 10 (PLA2G10) in epithelial cells promote the progression of CNAG to CAG through the transforming growth factor-β (TGF-β) signaling. We used RNA microarray and single-cell RNA sequencing datasets for bioinformatics analysis. The effects of PLA2G10 were verified by in vivo and in vitro experiments. The in vivo experiments used SD rats to establish a CNAG model for PLA2G10 and TGF-β intervention to observe the effects on gastric mucosal inflammation. In vitro experiments were conducted using human gastric mucosal epithelial cells (GES-1) for similar interventions. PLA2G10 inhibition led to the downregulation of TGF-β expression and attenuated the inflammatory response of the gastric mucosa. And the blockade of TGF-β signalling delayed the progression of CNAG to CAG, as evidenced by a reduction in inflammatory cell infiltration, a more regular cellular arrangement, and a reduction in collagen deposition. Our study shows that PLA2G10 plays a key role in the progression of chronic gastritis and highlights the important role played by the TGF-β signalling pathway in this process.

This study investigates the physiological basis for the inferior curing quality of low-quality flue-cured tobacco leaves. Using ‘Yunyan 300’ tobacco, we compared normal (CK), multi-fertilizer (LH), and reviving (FQ) leaves. Post-curing, LH and FQ leaves exhibited uneven, discoloured appearances versus the uniform golden-yellow CK. Physiologically, LH showed delayed water loss and electrolyte leakage, while FQ exhibited premature stress responses. Chemically, low-quality leaves maintained significantly higher post-curing nitrogenous compounds (total nitrogen, alkaloids, protein) and aberrant starch metabolism. Transmission electron microscopy revealed delayed chloroplast disassembly in LH and FQ, with persistent starch granules and tightly packed thylakoids. Pigment analysis showed significantly impaired degradation of chlorophylls and carotenoids in LH and FQ, leading to 30-40% greater accumulation of intermediate catabolites like pheophytin a and pheophorbide a (p < 0.05). Concurrently, the generation of final aroma-active degradation products (e.g., neophytadiene) was reduced. We conclude that the elevated initial levels of chlorophylls and carotenoids, coupled with metabolic dysregulation in low-quality tobacco leaves, collectively impair the complete enzymatic degradation of these pigments. This results in the accumulation of intermediate catabolites and an insufficient generation of key aroma precursors, thereby ultimately leading to the deterioration of both visual appearance and flavor quality.

Developing a new efficient separation ligand based on the “CHON” principle to address the limitations of phosphorus containing extractants in nuclear fuel reprocessing can help further simplify the process flow and reduce the amount of secondary waste. Building upon this critical need, a novel ligand was developed through a strategic application of the Hard and Soft Acids and Bases (HSAB) theory, integrating a soft donor nitrogen atom into the linear architecture of bis-diglycolamide. This groundbreaking ligand, named N,N′-bis[2-(2-(N,N-dioctylcarbamoyl)ethoxy)ethylacetamido]-N″-diethylenetriamine (TOMDEA-BisDGA), has demonstrated remarkable potential in the extraction of Pu(IV). The study unveils that the ligand demonstrates remarkable selectivity and separation efficiency towards Pu(IV) ions while maintaining an exceptionally low extraction capacity for U(VI) across a wide acidity spectrum of 0.1~6 mol/L. To explain the structure properties of complex formed by the ligand and Pu(IV), a systematic analysis was performed, including slope analysis, proton nuclear magnetic resonance (NMR) titration, and Fourier-transform infrared (FT-IR) spectroscopy. This study explores the coordination and separation behavior of diglycolamide ligands with actinide. This work is expected to provide important information and theoretical bases upon which advanced design and optimization of ligands for high-performance processes for the separation of plutonium might be carried out. Such findings will contribute to the understanding of actinide chemistry and further the design of improved separation methods for nuclear applications.

The use of tetra-alkylcarbamides as novel ligands: N,N-butyl-N’,N’-hexylurea (L1: ABHU), and N,N-butyl-N’,N’-pentylurea (L2: ABPU), for the solvent extraction and complexation behaviors of uranium(VI) was synthesized and investigated in this study. The effects of HNO3 and NO3− concentrations in the aqueous phase on the distribution ratio of U(VI) were examined. Under 5 mol/L HNO3 concentration, DU reached 5.02 and 4.94 respectively without third-phase formation. During the extraction, slope measurements and IR spectral analysis revealed that the U(VI) complexes are a form of UO2(NO3)2·2L for both ligands. In addition, thermodynamic studies showed that the uranium extraction reaction was a spontaneous exothermic reaction. The deep structural analysis of the complexes was realized with DFT calculation. The bond length, bond properties, and topology of the complexes were discussed in detail to analyze the extraction behavior. This study enriches the coordination chemistry of U(VI) by tetra-alkylcarbamides, which may offer new clues for the design and synthesis of novel ligands for the separation, enrichment, and recovery of uranium in the nuclear fuel cycle.

The progression of Chronic gastritis seems to follow a pattern from chronic non-atrophic gastritis (CNAG) to chronic atrophic gastritis (CAG) to cancer, so it is particularly important to block key targets in disease progression. A gene that synthesizes secreted phospholipase A2, attracted our attention. To study whether phospholipase A2 group 10 (PLA2G10) in epithelial cells promote the progression of CNAG to CAG through the transforming growth factor-[beta] (TGF-[beta]) signaling. We used RNA microarray and single-cell RNA sequencing datasets for bioinformatics analysis. The effects of PLA2G10 were verified by in vivo and in vitro experiments. The in vivo experiments used SD rats to establish a CNAG model for PLA2G10 and TGF-[beta] intervention to observe the effects on gastric mucosal inflammation. In vitro experiments were conducted using human gastric mucosal epithelial cells (GES-1) for similar interventions. PLA2G10 inhibition led to the downregulation of TGF-[beta] expression and attenuated the inflammatory response of the gastric mucosa. And the blockade of TGF-[beta] signalling delayed the progression of CNAG to CAG, as evidenced by a reduction in inflammatory cell infiltration, a more regular cellular arrangement, and a reduction in collagen deposition. Our study shows that PLA2G10 plays a key role in the progression of chronic gastritis and highlights the important role played by the TGF-[beta] signalling pathway in this process.

Breeding programmes have increased the yields of major crops, including maize ( Zea mays L.), but the suitability of optimized traits to future climates remains unclear. Here, by comparing the responses of 323 elite maize inbred lines from different breeding eras under natural field conditions, we show that while newer lines exhibit higher grain yield than the early released lines under standard growth, the bred trait of reduced tassel size increases the susceptibility of newly released lines to high temperature during flowering. We identified a potential threshold for spikelets per tassel (~700), over which maize can produce a stably high seed set ratio under warm conditions, and show that small-tassel (<700 spikelets per tassel) genotypes are now unsuitable in 23.7% of global maize-growing regions. Our work highlights the need to consider possible climate change maladaptation resulting from breeding programmes. By comparing the responses of 323 elite maize lines from different breeding eras, the authors demonstrate that reduced tassel size in newer lines can lead to increased susceptibility to high temperature. This highlights the potential for traits optimized by breeding to lead to climate maladaptation.

Copper anode slime produced by electrorefining copper has a high recovery value due to the valuable metals and platinum group metals present. Neither traditional cupellation processes nor hydrometallurgical leaching processes can solve the problem of arsenic enrichment in the system. According to thermodynamic analysis, vacuum carbothermal reduction is feasible, but the saturation vapor pressure varies greatly among the reduction products. Therefore, separation of arsenic oxide, lead-bismuth compounds and precious metal components can be achieved via vacuum carbothermal reduction with selective volatilization. At the vacuum carbothermal reduction stage (823 K), the arsenic content in the residue was reduced from 9.35% to 0.48%, indicating a 94.89% arsenic removal efficiency. The vacuum distillation stage (1173 K) exhibited 94.21% Pb and 98.19% Bi removal efficiencies, and the recovery efficiencies for silver and gold were 97.49% and 99.99%, respectively.

Developing a new efficient separation ligand based on the “CHON” principle to address the limitations of phosphorus containing extractants in nuclear fuel reprocessing can help further simplify the process flow and reduce the amount of secondary waste. Building upon this critical need, a novel ligand was developed through a strategic application of the Hard and Soft Acids and Bases (HSAB) theory, integrating a soft donor nitrogen atom into the linear architecture of bis-diglycolamide. This groundbreaking ligand, named N,N′-bis[2-(2-(N,N-dioctylcarbamoyl)ethoxy)ethylacetamido]-N″-diethylenetriamine (TOMDEA-BisDGA), has demonstrated remarkable potential in the extraction of Pu(IV). The study unveils that the ligand demonstrates remarkable selectivity and separation efficiency towards Pu(IV) ions while maintaining an exceptionally low extraction capacity for U(VI) across a wide acidity spectrum of 0.1~6 mol/L. To explain the structure properties of complex formed by the ligand and Pu(IV), a systematic analysis was performed, including slope analysis, proton nuclear magnetic resonance (NMR) titration, and Fourier-transform infrared (FT-IR) spectroscopy. This study explores the coordination and separation behavior of diglycolamide ligands with actinide. This work is expected to provide important information and theoretical bases upon which advanced design and optimization of ligands for high-performance processes for the separation of plutonium might be carried out. Such findings will contribute to the understanding of actinide chemistry and further the design of improved separation methods for nuclear applications.

IntroductionThe progression of Chronic gastritis seems to follow a pattern from chronic non-atrophic gastritis (CNAG) to chronic atrophic gastritis (CAG) to cancer, so it is particularly important to block key targets in disease progression. A gene that synthesizes secreted phospholipase A2, attracted our attention.ObjectivesTo study whether phospholipase A2 group 10 (PLA2G10) in epithelial cells promote the progression of CNAG to CAG through the transforming growth factor-β (TGF-β) signaling.MethodsWe used RNA microarray and single-cell RNA sequencing datasets for bioinformatics analysis. The effects of PLA2G10 were verified by in vivo and in vitro experiments. The in vivo experiments used SD rats to establish a CNAG model for PLA2G10 and TGF-β intervention to observe the effects on gastric mucosal inflammation. In vitro experiments were conducted using human gastric mucosal epithelial cells (GES-1) for similar interventions.ResultsPLA2G10 inhibition led to the downregulation of TGF-β expression and attenuated the inflammatory response of the gastric mucosa. And the blockade of TGF-β signalling delayed the progression of CNAG to CAG, as evidenced by a reduction in inflammatory cell infiltration, a more regular cellular arrangement, and a reduction in collagen deposition.ConclusionsOur study shows that PLA2G10 plays a key role in the progression of chronic gastritis and highlights the important role played by the TGF-β signalling pathway in this process.