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The main pipe of PWR is the key component of the steam supply system of nuclear power plant, and it is also an important part of the reactor coolant pressure boundary. The main pipe of the coolant system of light water reactor is made of cast stainless steel parts, which has high material strength, high toughness and good corrosion resistance. However, there is thermal aging embrittlement during longterm operation at 280325 ℃, resulting in the increase of hardness and tensile strength of stainless steel, and the significant decrease of impact energy and toughness. Therefore, the safety margin of the main pipeline should be analyzed and evaluated to ensure the safe and reliable operation, which is an important link in the aging management of the main pipeline. Especially when the nuclear power unit in service is ready to prolong its life, the requirements of thermal aging detection and evaluation of main pipeline are put forward. Therefore, it is necessary to use nondestructive method to detect the thermal aging of the main pipeline in service and evaluate the thermal aging state. The thermoelectric power of nuclear grade CF-8M static cast stainless steel main pipe material was measured after thermal aging test at 400 ℃ for 10 000 h. The relationship of mechanical properties (impact energy) and thermoelectric power with aging parameters after different thermal aging time was investigated, and the corresponding relationship between normalized parameters of thermal aging influencing factors and mechanical properties, thermoelectric power value was obtained. The experimental results show that the impact energy decreases rapidly in the initial stage, and the decreasing trend of impact energy tends to be gentle after thermal aging to 8 000 h. During the experiment, the thermoelectric power increases linearly with the increase of logarithmic aging time. With the increase of thermoelectric power, the impact energy begins to decrease rapidly, and then decreases slowly and gradually tends to saturation. The variation of impact energy with thermoelectric power is similar to that of impact energy with thermal aging time. Based on the linear relationship between the normalized parameters and thermoelectric power, the degree of performance degradation after thermal aging for service parts can be evaluated by the thermoelectric power. This experimental study provides a test basis for thermoelectric power detection and thermal aging evaluation of main pipe components onsite.

Oral squamous cell carcinoma (OSCC) stands as a prevalent subtype of head and neck squamous cell carcinoma, leading to disease recurrence and low survival rates. PPARγ, a ligand-dependent nuclear transcription factor, holds significance in tumor development. However, the role of PPARγ in the development of OSCC has not been fully elucidated. Through transcriptome sequencing analysis, we discovered a notable enrichment of ferroptosis-related molecules upon treatment with PPARγ antagonist. We subsequently confirmed the occurrence of ferroptosis through transmission electron microscopy, iron detection, etc. Notably, ferroptosis inhibitors could not completely rescue the cell death caused by PPARγ inhibitors, and the rescue effect was the greatest when disulfidptosis and ferroptosis inhibitors coexisted. We confirmed that the disulfidptosis phenotype indeed existed. Mechanistically, through qPCR and Western blotting, we observed that the inhibition of PPARγ resulted in the upregulation of heme oxygenase 1 (HMOX1), thereby promoting ferroptosis, while solute carrier family 7 member 11 (SLC7A11) was also upregulated to promote disulfidptosis in OSCC. Finally, a flow cytometry analysis of flight and multiplex immunohistochemical staining was used to characterize the immune status of PPARγ antagonist-treated OSCC tissues in a mouse tongue orthotopic transplantation tumor model, and the results showed that the inhibition of PPARγ led to ferroptosis and disulfidptosis, promoted the aggregation of cDCs and CD8+ T cells, and inhibited the progression of OSCC. Overall, our findings reveal that PPARγ plays a key role in regulating cell death in OSCC and that targeting PPARγ may be a potential therapeutic approach for OSCC. [ABSTRACT FROM AUTHOR]

Developing polymers with high electrical conductivity (σ) after n‐doping is a great challenge for the advance of the field of organic thermoelectrics (OTEs). Herein, we report a series of thiazole imide‐based n‐type polymers by gradually increasing selenophene content in polymeric backbone. Thanks to the strong intramolecular noncovalent N⋅⋅⋅S interaction and enhanced intermolecular Se⋅⋅⋅Se interaction, with the increase of selenophene content, the polymers show gradually lowered LUMOs, more planar backbone, and improved film crystallinity versus the selenophene‐free analogue. Consequently, polymer PDTzSI−Se with the highest selenophene content achieves a champion σ of 164.0 S cm−1 and a power factor of 49.0 μW m−1 K−2 in the series when applied in OTEs after n‐doping. The σ value is the highest one for n‐type donor‐acceptor OTE materials reported to date. Our work indicates that selenophene substitution is a powerful strategy for developing high‐performance n‐type OTE materials and selenophene incorporated thiazole imides offer an excellent platform in enabling n‐type polymers with high backbone coplanarity, deep‐lying LUMO and enhanced mobility/conductivity. [ABSTRACT FROM AUTHOR]

Dopant‐free hole transport layers (HTLs) play a crucial role in achieving high‐efficiency and stable perovskite solar cells (PSCs). However, only a limited number of these HTLs have demonstrated power conversion efficiencies (PCEs) surpassing 21%. Herein, the design and synthesis of two polymeric HTLs with a novel DA'D–A backbone are presented. The incorporation of two A units (benzothiazole and imide functionalized aromatics) in the polymer imparts a rigid backbone, high mobility, appropriate film morphology, excellent thermal stability, and a deeper highest occupied molecular orbital energy level, crucial for achieving a more suitable energy‐level alignment between HTL and perovskite layer. Notably, the champion PSC based on our HTLs exhibits a remarkable PCE of 22.02% with minimal hysteresis and excellent thermal stability, surpassing the performance of devices based on the benchmark polymeric HTL PTAA under identical conditions. These findings underscore the immense potential of our DA'D‐A backbone strategy in developing high‐performance dopant‐free polymer HTLs for enhancing the PCE of PSCs. [ABSTRACT FROM AUTHOR]

Based on the actual geological survey data and current national standard for drinking natural mineral water, this paper rechecks and counts the explored and evaluated drinking natural mineral water resources and their development and utilization of the urban belt in Anhui section of the Yangtze River. In combination of the mineral water resource endowment, economic and social development, and ecological environment protection needs, the study analyzed the main problems in the development and utilization of mineral water and put forward the countermeasures. The allowable mining capacity of the existing mineral water wells (springs) of the Anhui urban belt along of the Yangtze River is 17 540.45 m³/d, and the actual extracted amount is 1 306.39 m³/d, which only accounts for 7.45% of the allowable mining capacity. Besides the problems such as idle and insufficient resources, high-quality but low utilization, and inadequate protection, deep-seated constraints such as inadequate understanding on the chemical composition sources and mechanisms of mineral water, obscure conditions for sustainable utilization, and unreasonable resource reserves estimation are also widely ignored. In the future, the exploration and evaluation of mineral water should attach great importance to the comprehensive analysis of water chemistry and environmental isotopes, conduct in-depth research on water-rock interaction and sustainable resource utilization conditions, and correctly select resource reserve estimation methods based on hydrogeological conditions, providing a solid foundation for development and utilization. At the same time, we should scientifically plan the layout of mineral water exploration and development, and focus on the exploration and development of carbonated mineral water in Tianchang area and mineral water in Dabie Mountain, so as to boost industrial restructuring and rural revitalization. [ABSTRACT FROM AUTHOR]

A common dilemma with deep-learning-based solar power forecasting models is their heavy dependence on a large amount of training data. Few-Shot Solar Power Forecasting (FSSPF) has been investigated in this paper, which aims to obtain accurate forecasting models with limited training data. Integrating Transfer Learning and Meta-Learning, approaches of Feature Transfer and Rapid Adaptation (FTRA), have been proposed for FSSPF. Specifically, the adopted model will be divided into Transferable learner and Adaptive learner. Using massive training data from source solar plants, Transferable learner and Adaptive learner will be pre-trained through a Transfer Learning and Meta-Learning algorithm, respectively. Ultimately, the parameters of the Adaptive learner will undergo fine-tuning using the limited training data obtained directly from the target solar plant. Three open solar power forecasting datasets (GEFCom2014) were utilized to conduct 24-h-ahead FSSPF experiments. The results illustrate that the proposed FTRA is able to outperform other FSSPF approaches, under various amounts of training data as well as different deep-learning models. Notably, with only 10-day training data, the proposed FTRA can achieve an RMSR of 8.42%, which will be lower than the 0.5% achieved by the state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

Polymerized small molecule acceptors have recently greatly facilitated the development of all‐polymer solar cells (All‐PSCs) with respect to the power conversion efficiencies (PCEs). However, high‐performance and low‐cost polymer donors for All‐PSCs are still lacking, limiting further large‐scale manufacturing of All‐PSCs. Herein, this work designs and synthesizes a new thiophene derivative, FETVT, featuring vinyl‐bridged fluorine and ester‐substituted monothiophene. Incorporation of FETVT into a polymer yields a high‐performance polythiophene derivative PFETVT‐T, which exhibits deep‐lying HOMO level, suitable solution pre‐aggregation ability, finely‐tuned polymer crystallinity, and appropriate thermodynamic miscibility with the polymer acceptor L15. As a result, binary based on PFETVT‐T achieves a record PCE of 11.81% with agood stability, representing a breakthrough for polythiophenes and their derivatives‐based All‐PSCs, which is also significantly higher than that (1.92%) of All‐PSCs based on its isomerized analog. Remarkably, PFETVT‐T achieves an impressive PCE exceeding 16% via the implementation of a ternary blend design. These findings offer a hopeful pathway toward attaining high‐performance, stable, and cost‐effective PSCs. [ABSTRACT FROM AUTHOR]