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China Foundry 2025年

作者： Wen-tong Liu Yi-dong wu Lei Gao Jing-yang Chen cheng-bo Xiao Xi-dong Hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The size and shape effect(SSE) of components has become a critical issue for mechanical properties, application reliability, and processing. In this study, the creep rupture life(CRL) of components with different wall thicknesses and positions in a combustion chamber casing simulator made of K439B superalloy was investigated. The intrinsic mechanisms of the SSE were explored from the dendrite structure, volume fraction and size of the γ' phase, and element segregation, etc. It is shown that this casting exhibits a strong SSE of creep rupture life, characterized by a significant difference in the CRL values up to 60% with the variation of wall thickness and position in the casing. In terms of casting technology, the influence of SSE on CRL is actually determined by the cooling rate. The SSE on the creep rupture life originates from the dendrite structure(such as the secondary dendrite arm spacing), volume fraction size of the γ' phase in the dendrite trunk, and elements segregation rate. This work may have implications for the design and application of engineering components with large sizes and complex structures.

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考虑热力学非平衡效应的高马赫数超燃冲压发动机湍流燃烧数值研究

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实验流体力学 2025年第1期39卷 30-37页

作者：冯海金台吴坤浙江大学航空航天学院杭州310027 中国科学院力学研究所北京100190

高超声速飞行过程中,随着马赫数升高,边界层内温度快速上升,分子振动能、电子能被激发,气体分子发生离解甚至电离,使得量热完全气体假设失效。针对高温热化学非平衡气体,采用热力学平衡模型及Park的双温度非平衡模型对飞行马赫数Ma=12... 详细信息

高超声速飞行过程中,随着马赫数升高,边界层内温度快速上升,分子振动能、电子能被激发,气体分子发生离解甚至电离,使得量热完全气体假设失效。针对高温热化学非平衡气体,采用热力学平衡模型及Park的双温度非平衡模型对飞行马赫数Ma=12条件下的超燃冲压发动机进行了数值模拟。研究结果表明:与平衡态计算结果相比,非平衡效应使得波系位置前移,激波间峰值压力升高,对冷场的影响更加明显;非平衡态平动温度场与平衡态差别不大,热力学非平衡效应使平动温度Ttr略微升高;非平衡态燃烧室出口截面燃烧效率更低,热力学非平衡效应会降低反应程度。

关键词：高超声速热力学非平衡超燃冲压发动机波系结构燃烧效率数值模拟

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-wu Zhong CAS Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of TechnologyHefei 230009China State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsWuhan UniversityWuhan 430072China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cost and long-term *** are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices,artificial photosynthesis,photocatalysis,biodiagnostics,and therapeutics,*** review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes,including photoactive Zr,V,Cr,Mo,and W complexes,Mn complexes and hybrids,Fe,Co,Ni,and Cu complexes,and Zn and Cd complexes and hybrids.A particular focus is given on the molecular design,modulation of photophysical and photochemical properties,and applications of the representative and lately-developed nonprecious metal *** addition,a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

Pancreatic stent improves the success rate of needle-knife papillotomy in patients with difficult biliary cannulation

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World Journal of Gastroenterology 2025年第1期31卷 58-67页

作者： Mu-Hsien Lee cheng-Hui Lin Chi-Huan wu Yung-Kuan Tsou Kai-Feng Sung Sheng-Fu Wang Nai-Jen Liu Department of Gastroenterology and Hepatology Chang Gung Memorial Hospital and Chang Gung University College of MedicineTaoyuan 33305Taiwan School of Medicine Chang Gung UniversityTaoyuan 33305Taiwan

BACKGROUND Needle-knife precut papillotomy(NKP)is typically performed ***,it remains unclear whether pancreatic stent(PS)placement can improve the outcomes of *** To explore whether PS placement improves the success rate of NKP in patients with difficult biliary *** This single-center retrospective study included 190 patients who underwent NKP between January 2017 and December 2021 after failed conventional biliary *** cases with incidental pancreatic duct cannulation during conventional biliary cannulation,the decision for pre-NKP PS placement was made at the endoscopist's *** primary outcome was the difference in the NKP success rate between patients with and without PS placement;the secondary outcome was the adverse event *** Among the 190 participants,82 received pre-NKP PS(PS-NKP group)whereas 108 did not[freehand or freehand NKP(FH-NKP)group].Post-NKP selective biliary cannulation was successful in 167(87.9%)patients,and the PS-NKP had a significantly higher success rate than the FH-NKP group(93.9%vs 83.3%,P=0.027).The overall adverse event rates were 7.3%and 11.1%in the PS-NKP and FH-NKP groups,respectively(P=0.493).A periampullary diverticulum(PAD)and significant intraoperative bleeding during NKP were independently associated with NKP failure;however,a pre-NKP PS was the only predictor of NKP *** the 44 participants with PADs,the PS-NKP group had a non-significantly higher NKP success rate than the FH-NKP group(87.5%and 65%,respectively;P=0.076).CONCLUSION PS significantly improved the success rate of NKP in patients with difficult biliary cannulation.

关键词： Difficult biliary cannulation Endoscopic retrograde cholangiopancreatography Needle-knife papillotomy Pancreatic stent Selective biliary cannulation

Predictors of Successful Radiofrequency Ablation of Benign Thyroid Nodules: A Single Centre Analysis

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International Journal of Clinical Medicine 2025年第1期16卷 16-28页

作者： Waswa Edgar Jiangyuan cheng Esraa Atef Saad Mwale Paul wu Meng Department of General and Interventional Ultrasound Zhongnan Hospital of Wuhan University Wuhan China

Objective: To assess the predictors of successful inactivation of benign thyroid nodules using radiofrequency ablation (RFA) and the hormonal responses thereafter. Methods: A retrospective study conducted at Zhongnan Hospital of wuhan University (January 2022 to January 2024) analysed thyroid tumor characteristics using B-mode ultrasound, colour Doppler imaging, and CEUS post-RFA. Thyroid hormone levels were also assessed before RFA and at 1, 3, and 6 months after the procedure. Results: The study involved 72 patients with benign thyroid nodules, comprising 13 males and 59 females, with a mean age of 45.8 ± 12.1 years. Complete inactivation was achieved in 70.8% of nodules, while 29.2% showed partial inactivation. Nodules with complete inactivation exhibited more calcification (p = 0.040), whereas those with partial inactivation demonstrated higher vascularity (p Conclusion: In conclusion, this study found that therapeutic RFA effectively achieves high rates of complete inactivation in benign thyroid nodules, with the degree of inactivation mainly influenced by nodule vascularity and calcifications.

关键词： Predictors Radiofrequency Ablation Benign Thyroid Nodules

Microstructure Evolution and Mechanism of Strength Development of Fly Ash Paste

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 152-163页

作者： MA Shuzhao wu Shunchuan HUANG Mingqing cheng Haiyong JIANG Guanzhao NIU Yonghui LIU Zemin SUN Wei Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Zijin School of Ge-ology and Mining Fuzhou UniversityFuzhou 350108China

Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash *** conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the *** mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were *** results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased *** the content exceeded 4%,the rate of increase in strength *** on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping *** activation effect was poor for long-term strength after 28 *** CaO content did not significantly affect the degree of activation *** maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the *** activators also corroded the surface of the fly ash particles,resulting in a pozzolanic *** active substances in fly ash were released efficiently,and hydration was *** pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.

关键词： paste filling fly ash activator unconfined compressive strength microstructure hydration simulation

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横向联邦学习:研究现状、系统应用与挑战

计算机学报 2025年第1期48卷 35-67页

作者：吴文泰吴应良林伟伟左文明暨南大学信息科学技术学院广州510632 华南理工大学电子商务系广州510006 华南理工大学计算机科学与工程学院广州510006 人工智能与数字经济广东省实验室(广州) 广州510335

随着数据和算力向网络边缘下沉,人工智能应用的研发愈加依赖隐私敏感的用户数据。在这一趋势的推动下,联邦学习因其强调隐私保护的特性而逐渐成为一个广泛应用的分布式机器学习框架。作为联邦学习的原始范式,横向联邦学习(Horizontal Fe... 详细信息

随着数据和算力向网络边缘下沉,人工智能应用的研发愈加依赖隐私敏感的用户数据。在这一趋势的推动下,联邦学习因其强调隐私保护的特性而逐渐成为一个广泛应用的分布式机器学习框架。作为联邦学习的原始范式,横向联邦学习(Horizontal Federated Learning,HFL)具有扩展能力强和使用场景广泛等特点,因此是近年来该领域的研究重心,同时在产业界相关需求的驱动下有着十分广泛的应用前景。横向联邦学习的研究涉及机器学习、分布式系统、无线通信和信息安全等多个学术领域,从研究动机到技术方法都呈现多样化,但现有文献未能展现相关研究现状的全貌。此外,横向联邦学习相关技术的发展催化出了一系列开源系统框架、公开数据集以及多种场景下的应用,对进一步研究与实践都具有参考价值。为此,本文对横向联邦学习的研究现状和系统应用进行综合性调研:首先,对相关文献按照研究目标和技术角度进行全面地分类梳理,从多领域视角分析了各分支的研究现状;其次,从应用实践的视角,对比分析了面向横向联邦学习的主流系统框架与代码库、描述了数据准备方法以及典型的应用场景。在此基础上,阐明了横向联邦学习算法研究和系统应用面临的6个关键挑战,为如何缩小相关研究与系统实践之间的鸿沟提供了新的参考。

关键词：横向联邦学习数据隐私分布式系统机器学习人工神经网络

Discovery of primary lung cancer following resection of rectal cancer lung metastasis:A case report

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World Journal of Clinical Oncology 2025年第2期16卷 173-179页

作者： Fei-Yan Zhou Fang-Hua Song Zhen-Hao cheng Sen wu Department of Oncology II Xinhua HospitalDalian UniversityDalian 116000Liaoning ProvinceChina

BACKGROUND Colorectal cancer(CRC)ranks high among the most common types of malignant *** primary cause of cancer-related mortality is metastasis,with lung metastases accounting for 32.9%of all cases of metastatic CRC(MCRC).However,cases of MCRC in the lungs,which present concurrently with primary peripheral lung adenocarcinoma,are exceptionally *** SUMMARY This report describes the case of a 52-year-old female patient who,following a colonoscopy,was diagnosed with moderately differentiated adenocarcinoma based on rectal mucosal biopsy findings.A preoperative chest computed tomography scan revealed a ground-glass nodule in the right lung and a small nodule(approximately 0.6 cm in diameter)in the extramural basal segment of the left lower lobe,which suggested multiple lung metastases from rectal *** treatment and follow-up led to a diagnosis of rectal cancer with left lung metastasis and peripheral adenocarcinoma of the lower lobe of the right *** This case report describes the therapeutic journey of a patient with lung metastasis from rectal cancer in addition to primary peripheral adenocarcinoma,thus underscoring the critical roles of multidisciplinary collaboration,personalized treatment strategies,and comprehensive patient rehabilitation guidance.

关键词： Rectal cancer Metastatic lung cancer Peripheral lung adenocarcinoma Double primary cancer Case report

磷酸铁锂离子电池热失控产物爆炸下限预测方法

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爆炸与冲击 2025年第2期45卷 126-136页

作者：袁帅台枫钱新明程东浩中国民航科学技术研究院北京101399 北京理工大学爆炸科学与安全防护全国重点实验室北京100081 北京市民航安全分析及预防工程技术研究中心北京100028

为准确预测磷酸铁锂电池热失控产物的爆炸下限,在密闭压力容器内开展了磷酸铁锂电池热失控实验,结合热失控特性和气相色谱-质谱联用技术,计算了热失控产物气体组分,基于能量守恒方程和绝热火焰温度,建立了磷酸铁锂电池热失控产物爆炸下... 详细信息

为准确预测磷酸铁锂电池热失控产物的爆炸下限,在密闭压力容器内开展了磷酸铁锂电池热失控实验,结合热失控特性和气相色谱-质谱联用技术,计算了热失控产物气体组分,基于能量守恒方程和绝热火焰温度,建立了磷酸铁锂电池热失控产物爆炸下限的预测模型,并验证了绝热火焰温度法、Le Chatelier法和Jones法的准确性,考察了电解液蒸气对热失控产物爆炸下限的影响。结果表明,常温下采用Le Chatelier法计算得到的爆炸下限偏差最小,为1.14%;采用绝热火焰温度法计算结果偏差最大,为10.02%。在60%~100%荷电状态(state of charge, SOC)范围内,磷酸铁锂电池热失控气体的爆炸下限先升后降。当热失控产物考虑电解液蒸气时,60%SOC磷酸铁锂电池热失控产物爆炸下限仅为3.93%,较未考虑电解液蒸气热失控气体的爆炸下限降低了22.49%,这说明电解液蒸气提高了磷酸铁锂电池热失控产物的爆炸风险。

关键词：磷酸铁锂电池热失控产物爆炸下限 Le Chatelier定律绝热火焰温度

Evaluation of three lymph node staging systems for prognostic prediction in gastric cancer:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 334-348页

作者： Ming cheng Yang Yu Takehiro Watanabe Yutaro Yoshimoto Sanae Kaji Yukinori Yube Munehisa Kaneda Hajime Orita Shinji Mine You-Yong wu Tetsu Fukunaga Department of Upper Gastroenterological Surgery Juntendo University School of MedicineTokyo 113-8431Japan Department of Gastrointestinal Surgery The Second Affiliated Hospital of Soochow UniversitySuzhou 215004Jiangsu ProvinceChina Department of Gastrointestinal Surgery Peking University Cancer HospitalBeijing 100142China

BACKGROUND Lymph node status is a critical prognostic factor in gastric cancer(GC),but stage migration may occur in pathological lymph nodes(pN)*** address this,alternative staging systems such as the positive lymph node ratio(LNR)and log odds of positive lymph nodes(LODDS)were *** To assess the prognostic accuracy and stratification efficacy of three nodal staging systems in *** A systematic review identified 12 studies,from which hazard ratios(HRs)for overall survival(OS)were *** analyses,subgroup analyses,publication bias assessments,and quality evaluations were *** enhance comparability,data from studies with identical cutoff values for pN,LNR,and LODDS were *** stratification was then applied to generate Kaplan-Meier(KM)survival curves,assessing the stratification efficacy of three staging *** The HRs and 95%confidence intervals for pN,LNR,and LODDS were 2.16(1.72-2.73),2.05(1.65-2.55),and 3.15(2.15-4.37),respectively,confirming all three as independent prognostic risk factors for *** analysis of HRs demonstrated that LODDS had superior prognostic predictive power over LNR and *** curves for pN(N0,N1,N2,N3a,N3b),LNR(0.1/0.2/0.5),and LODDS(-1.5/-1.0/-0.5/0)revealed significant differences(P<0.001)among all prognostic *** differences and standard deviations in 60-month relative survival were 27.93%±0.29%,41.70%±0.30%,and 26.60%±0.28%for pN,LNR,and LODDS,*** All three staging systems are independent prognostic factors for *** demonstrated the highest specificity,making it especially useful for predicting outcomes,while pN was the most effective in homogeneous stratification,offering better patient *** findings highlight the complementary roles of LODDS and pN in enhancing prognostic accuracy and stratification.

关键词： Gastric cancer Prognostic predictor Overall survival Meta-analysis Pathological lymph nodes Positive lymph node ratio Log odds of positive lymph nodes