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Molecular composition of water soluble fraction of petroleum products and crude oils:Insights into groundwater contamination potential and environmental forensics
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作者 Wang Yu Yuruo Wan +3 位作者 wei zhou Jiayi An Liting Tian Jie Ma 《Journal of Environmental Sciences》 2026年第1期437-444,共8页
Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.Th... Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.The aim of this study was to assess impact of 15 diverse oils on groundwater quality and environmental forensics based on oil-water equilibrium experiments.Our results indicate that contamination of groundwater by gasoline and naphtha is primarily attributed to volatile hydrocarbons,while pollution from diesel,kerosene,and crude oil is predominantly from non-hydrocarbons.Rapid determination of the extent of non-hydrocarbon pollution in WSFs was achieved through a new quantitative index.Gasoline and naphtha exhibited the highest groundwater contamination potential while kerosene and light crude oils were also likely to cause groundwater contamina-tion.Although volatile hydrocarbons in the WSFs of diesel and jet fuel do not easily exceed current regulatory standards,unregulated non-hydrocarbons may pose a more severe contamination risk to groundwater.Notably,the presence of significant benzene and toluene,hydrogenation and alkylation products(e.g.,C4-C5 alkylben-zenes,alkylindenes,alkyltetralins,and dihydro-indenes),cycloalkanes in WSFs can effectively be utilized for preliminary source identification of light distillates,middle distillates,and crude oils,respectively. 展开更多
关键词 Petroleum hydrocarbons Water soluble fraction Contaminated sites Groundwater contamination Source identification
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Pulsed Dynamic Water Electrolysis:Mass Transfer Enhancement,Microenvironment Regulation,and Hydrogen Production Optimization
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作者 Xuewei Zhang wei zhou +7 位作者 Xiaoxiao Meng Yuming Huang Yang Yu Haiqian Zhao Lijie Wang Fei Sun Jihui Gao Guangbo Zhao 《Nano-Micro Letters》 2026年第3期807-859,共53页
Pulsed dynamic electrolysis(PDE),driven by renewable energy,has emerged as an innovative electrocatalytic conversion method,demonstrating significant potential in addressing global energy challenges and promoting sust... Pulsed dynamic electrolysis(PDE),driven by renewable energy,has emerged as an innovative electrocatalytic conversion method,demonstrating significant potential in addressing global energy challenges and promoting sustainable development.Despite significant progress in various electrochemical systems,the regulatory mechanisms of PDE in energy and mass transfer and the lifespan extension of electrolysis systems,particularly in water electrolysis(WE)for hydrogen production,remain insufficiently explored.Therefore,there is an urgent need for a deeper understanding of the unique contributions of PDE in mass transfer enhancement,microenvironment regulation,and hydrogen production optimization,aiming to achieve low-energy consumption,high catalytic activity,and long-term stability in the generation of target products.Here,this review critically examines the microenvironmental effects of PDE on energy and mass transfer,the electrode degradation mechanisms in the lifespan extension of electrolysis systems,and the key factors in enhancing WE for hydrogen production,providing a comprehensive summary of current research progress.The review focuses on the complex regulatory mechanisms of frequency,duty cycle,amplitude,and other factors in hydrogen evolution reaction(HER)performance within PDE strategies,revealing the interrelationships among them.Finally,the potential future directions and challenges for transitioning from laboratory studies to industrial applications are proposed. 展开更多
关键词 Pulsed dynamic electrolysis Water electrolysis Energy and mass transfer MICROENVIRONMENT System stability
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Experimental and numerical investigation of Weibullian behavior of grain crushing strength 被引量:10
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作者 Quanshui Huang wei zhou +2 位作者 Gang Ma Tang-Tat Ng Kun Xu 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第2期401-411,共11页
The Weibullian behavior of single grain crushing strength was investigated experimentally and numerically with the aim of enhancing the understanding of rock grain breakage.The morphologies of pebble grains were obtai... The Weibullian behavior of single grain crushing strength was investigated experimentally and numerically with the aim of enhancing the understanding of rock grain breakage.The morphologies of pebble grains were obtained using white light 3D laser scanning and image processing.A grain shape library was constructed for grain shape analysis with different shape descriptors.The use of the shape library and grain stability analysis is discussed for a suggested procedure to rotate a grain to its most stable configuration.Single grain crushing tests were performed for 30 pebbles to obtain force-displacement curves and fracture patterns.Each grain was compressed diametrically between flat platens.As expected,the values of the stress at bulk fracture follow a Weibull distribution.A procedure for generating crushable agglomerates with realistic particle shapes was demonstrated,which was accomplished in the discrete element modeling(DEM)of the single grain crushing test.The work presented here is novel in that both the heterogeneous micro-structures and randomly distributed flaws are considered.The DEM results demonstrate that the proposed modeling approach and calibrated parameters are reliable and can reflect the crushing behavior of rock pebbles.Finally,three parametric studies were presented evaluating the effects of micro-crack density,micro-crack disorder,and grain morphology on the Weibullian behavior of the crushing strength,none of which has previously been thoroughly considered.These three studies provide a deeper insight into the origin of the Weibullian behavior of single grain crushing strength. 展开更多
关键词 Rock grain Grain crushing test Discrete element modeling 3D scanning technique Grain stability Weibullian behavior
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基于复合域多尺度分解的红外偏振图像融合方法 被引量:2
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作者 陈广秋 魏洲 +1 位作者 段锦 黄丹丹 《吉林大学学报(理学版)》 北大核心 2025年第2期479-491,共13页
针对目前红外偏振融合图像质量差、偏振信息缺失、目标纹理细节不够等问题,提出一种基于复合域多尺度分解的红外偏振图像融合方法.首先,在空间域内利用引导滤波器对源图像进行二尺度分解,得到细节层和基础层,在频域内利用非下采样剪切... 针对目前红外偏振融合图像质量差、偏振信息缺失、目标纹理细节不够等问题,提出一种基于复合域多尺度分解的红外偏振图像融合方法.首先,在空间域内利用引导滤波器对源图像进行二尺度分解,得到细节层和基础层,在频域内利用非下采样剪切波变换对基础层图像进行多尺度多方向分解,得到低频子带图像和高频子带图像;其次,对高频子带采用主成分分析-自适应脉冲耦合神经网络融合规则,对低频子带采用改进的卷积稀疏表示进行系数合并,细节层融合采用基于像素相似度的局部能量加权和选择性融合规则;最后,在复合域内利用逆变换重构出融合图像.实验结果表明,该方法在主观视觉性能和8个客观评价指标上均优于其他对比融合方法,说明该方法在红外偏振图像融合中具有较多优势,能有效提高融合图像的质量. 展开更多
关键词 红外偏振图像融合 非下采样剪切波变换 自适应脉冲耦合神经网络 卷积稀疏表示
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基于多尺度特征的渐进式红外偏振图像融合方法
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作者 陈广秋 魏洲 +1 位作者 段锦 黄丹丹 《湖南大学学报(自然科学版)》 北大核心 2025年第12期164-175,共12页
在复杂环境下,传统的红外探测方法具有较大的局限性,需要将偏振技术与红外技术融合.针对现有的卷积神经网络方法多尺度信息提取能力不足和融合子网融合不充分的问题,为了改善红外偏振融合图像质量,提高红外成像技术在复杂背景下的目标... 在复杂环境下,传统的红外探测方法具有较大的局限性,需要将偏振技术与红外技术融合.针对现有的卷积神经网络方法多尺度信息提取能力不足和融合子网融合不充分的问题,为了改善红外偏振融合图像质量,提高红外成像技术在复杂背景下的目标识别能力,本文提出了一种基于多尺度特征的渐进式红外偏振图像融合方法(progressive infrared polarization image fusion method based on multi-scale features, PIPFuse).首先,特征提取部分采用语义提取模块和多尺度密集块,用来提取语义增强的多尺度深度特征;其次,为了减少信息丢失和增强显著信息,融合子网采用渐进式差异信息增强融合模块进行特征融合;最后,通过解码融合特征得到最终的融合图像.与9种经典图像融合方法比较,该方法在6项评价指标上均优于其他对比融合方法,且主观视觉上目标纹理更加清晰,对比度更高. 展开更多
关键词 红外成像 多尺度特征 渐进策略 图像融合 卷积神经网络
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海水直接电解制氢体系阴极碱垢的形成机制及抑制策略
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作者 袁骏舒 周伟 +3 位作者 于洋 王星星 黄玉明 孟晓晓 《化学进展》 北大核心 2025年第8期1142-1155,共14页
氢能是未来能源的理想载体,传统的化石燃料重整制氢方式不能从根本上解决碳排放问题,海水直接电解制氢是未来极具发展前景的新型制氢方式。相比于传统基于纯水的电解制氢技术,天然海水在成分上更复杂,电解过程中发生的副反应更多,对电... 氢能是未来能源的理想载体,传统的化石燃料重整制氢方式不能从根本上解决碳排放问题,海水直接电解制氢是未来极具发展前景的新型制氢方式。相比于传统基于纯水的电解制氢技术,天然海水在成分上更复杂,电解过程中发生的副反应更多,对电极材料、电解槽结构设计等提出了更高要求。阳极析氯反应(CER)及阴极钙镁离子沉淀反应是海水直接电解技术面临的两大挑战。近年来已有大量文献报道CER的发生机理及抑制方法。相比之下,针对阴极钙镁离子沉积问题的机制及抑制策略讨论较少。在实际电解制氢过程中,阴极表面因钙镁离子沉积导致的电极传质阻力增大、电解效率降低等问题需重点关注。为此,本文从电极表面钙镁离子沉淀的形成机制出发,介绍了直接电解海水制氢的基本原理、面临的挑战,并对近年来针对阴极无机沉淀的抑制策略的研究进行了总结。最后,本文对未来海水直接电解制氢的研究方向进行了展望。 展开更多
关键词 海水电解 氢能 阴极 阻垢策略
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洗护用品包装设计中的视觉性表达方法与应用研究 被引量:1
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作者 周玮 李钢 《日用化学工业(中英文)》 北大核心 2025年第7期928-936,共9页
随着商品市场的日益繁荣和消费者需求的多样化,传统单一的包装形式已难以满足市场需求。本文旨在通过产品视觉性表达的分析视角,提出洗护用品包装设计的新思路和方法,以提升产品的市场竞争力,满足消费者对于审美与实用功能的双重追求。... 随着商品市场的日益繁荣和消费者需求的多样化,传统单一的包装形式已难以满足市场需求。本文旨在通过产品视觉性表达的分析视角,提出洗护用品包装设计的新思路和方法,以提升产品的市场竞争力,满足消费者对于审美与实用功能的双重追求。首先,本文基于对视觉性表达的概述,探讨了其对洗护用品包装设计的重要价值;然后,分析了洗护用品包装的视觉性表达设计原则;其次,通过对洗护品牌包装设计的现存问题分析,指出洗护用品包装视觉性表达设计存在创意同质化、忽视文化元素、视觉元素堆砌、忽视用户体验等问题;最后,有针对性地提出了强化创意独特性、融入文化元素、注重整体协调性、增强互动参与等产品包装视觉性表达设计的优化策略,以期为洗护用品包装设计提供新的理论支持和实践指导。 展开更多
关键词 视觉性表达 洗护用品 包装设计 品牌塑造 优化策略
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Exploring DeepSeek:A Survey on Advances,Applications,Challenges and Future Directions 被引量:6
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作者 Zehang Deng Wanlun Ma +4 位作者 Qing-Long Han wei zhou Xiaogang Zhu Sheng Wen Yang Xiang 《IEEE/CAA Journal of Automatica Sinica》 2025年第5期872-893,共22页
The rapid advancement of large models has led to the development of increasingly sophisticated models capable of generating diverse,personalized,and high-quality content.Among these,DeepSeek has emerged as a pivotal o... The rapid advancement of large models has led to the development of increasingly sophisticated models capable of generating diverse,personalized,and high-quality content.Among these,DeepSeek has emerged as a pivotal open-source initiative,demonstrating high performance at significantly lower computation costs compared to closed-source counterparts.This survey provides a comprehensive overview of the DeepSeek family of models,including DeepSeek-V3 and DeepSeek-R1,covering their core innovations in architecture,system pipeline,algorithm,and infrastructure.We explore their practical applications across various domains,such as healthcare,finance,and education,highlighting their impact on both industry and society.Further-more,we examine potential security,privacy,and ethical concerns arising from the widespread deployment of these models,emphasizing the need for responsible AI development.Finally,we outline future research directions to enhance the performance,safety,and scalability of DeepSeek models,aiming to foster further advancements in the open-source large model community. 展开更多
关键词 DeepSeek large language model large multimodal model
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融合UBD理论的C语言课程探究式单元教学设计
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作者 张君茹 周伟 谭振江 《计算机教育》 2025年第11期182-187,共6页
为提升高校C语言课程教学质量,解决传统教学中重记忆轻思维、学生实践能力薄弱等问题,提出融合UBD理论的探究式教学框架,以C语言循环单元为例,逆向设计教学过程,从确定预期结果、确定合适评估证据、设计学习体验3方面介绍教学设计,最后... 为提升高校C语言课程教学质量,解决传统教学中重记忆轻思维、学生实践能力薄弱等问题,提出融合UBD理论的探究式教学框架,以C语言循环单元为例,逆向设计教学过程,从确定预期结果、确定合适评估证据、设计学习体验3方面介绍教学设计,最后说明教学成效。该教学框架旨在助力高校一线教师精准锚定教学目标,提高教学效率,为完善高等教育跨学科教学设计提供全新思路。 展开更多
关键词 UBD理论 单元教学设计 探究式教学 C语言
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High-entropy materials for solid oxide cells:Synthesis,applications,and prospects 被引量:2
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作者 Ming Xiao Zuoqing Liu +8 位作者 Haosong Di Yuesheng Bai Guangming Yang Dmitry A.Medvedev Zhixin Luo wei Wang wei zhou Ran Ran Zongping Shao 《Journal of Energy Chemistry》 2025年第5期268-296,共29页
As global energy demand increases and environmental standards tighten,the development of efficient,eco-friendly energy conversion and storage technologies becomes crucial.Solid oxide cells(SOCs)show great promise beca... As global energy demand increases and environmental standards tighten,the development of efficient,eco-friendly energy conversion and storage technologies becomes crucial.Solid oxide cells(SOCs)show great promise because of their high energy conversion efficiency and wide range of applications.Highentropy materials(HEMs),a novel class of materials comprising several principal elements,have attracted significant interest within the materials science and energy sectors.Their distinctive structural features and adaptable functional properties offer immense potential for innovation across various applications.This review systematically covers the basic concepts,crystal structures,element selection,and major synthesis strategies of HEMs,and explores in detail the specific applications of these materials in SOCs,including its potential as air electrodes,fuel electrodes,electrolytes,and interconnects(including barrier coatings).By analyzing existing studies,this review reveals the significant advantages of HEMs in enhancing the performance,anti-poisoning,and stability of SOCs;highlights the key areas and challenges for future research;and looks into possible future directions. 展开更多
关键词 Solid oxide cells High-entropy materials Air electrodes Fuel electrodes Electrolytes Interconnects
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The Security of Using Large Language Models:A Survey With Emphasis on ChatGPT 被引量:2
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作者 wei zhou Xiaogang Zhu +4 位作者 Qing-Long Han Lin Li Xiao Chen Sheng Wen Yang Xiang 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期1-26,共26页
ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential sec... ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential security risks that need to be carefully evaluated and addressed. In this survey, we provide an overview of the current state of research on security of using ChatGPT, with aspects of bias, disinformation, ethics, misuse,attacks and privacy. We review and discuss the literature on these topics and highlight open research questions and future directions.Through this survey, we aim to contribute to the academic discourse on AI security, enriching the understanding of potential risks and mitigations. We anticipate that this survey will be valuable for various stakeholders involved in AI development and usage, including AI researchers, developers, policy makers, and end-users. 展开更多
关键词 Artificial intelligence(AI) ChatGPT large language models(LLMs) SECURITY
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When Software Security Meets Large Language Models:A Survey 被引量:2
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作者 Xiaogang Zhu wei zhou +3 位作者 Qing-Long Han Wanlun Ma Sheng Wen Yang Xiang 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期317-334,共18页
Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, ... Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, software testing and analysis are two of the critical methods, which significantly benefit from the advancements in deep learning technologies. Due to the successful use of deep learning in software security, recently,researchers have explored the potential of using large language models(LLMs) in this area. In this paper, we systematically review the results focusing on LLMs in software security. We analyze the topics of fuzzing, unit test, program repair, bug reproduction, data-driven bug detection, and bug triage. We deconstruct these techniques into several stages and analyze how LLMs can be used in the stages. We also discuss the future directions of using LLMs in software security, including the future directions for the existing use of LLMs and extensions from conventional deep learning research. 展开更多
关键词 Large language models(LLMs) software analysis software security software testing
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Strengthening Biomedical Big Data Management and Unleashing the Value of Data Elements 被引量:1
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作者 wei zhou Jing-Chen Zhang De-Pei Liu 《Chinese Medical Sciences Journal》 2025年第1期1-2,I0001,共3页
On October 18,2017,the 19th National Congress Report called for the implementation of the Healthy China Strategy.The development of biomedical data plays a pivotal role in advancing this strategy.Since the 18th Nation... On October 18,2017,the 19th National Congress Report called for the implementation of the Healthy China Strategy.The development of biomedical data plays a pivotal role in advancing this strategy.Since the 18th National Congress of the Communist Party of China,China has vigorously promoted the integration and implementation of the Healthy China and Digital China strategies.The National Health Commission has prioritized the development of health and medical big data,issuing policies to promote standardized applica-tions and foster innovation in"Internet+Healthcare."Biomedical data has significantly contributed to preci-sion medicine,personalized health management,drug development,disease diagnosis,public health monitor-ing,and epidemic prediction capabilities. 展开更多
关键词 health medical big dataissuing drug development precision medicine disease diagnosis development biomedical data personalized health management standardized app biomedical big data
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Sulfonatoproxylated cucurbit[7]urils as highly water-soluble and biocompatible excipients for solubilizing poorly soluble drugs and improving the bioavailability of indomethacin 被引量:1
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作者 Pei-Pei Liu Jia-Bin Xing +7 位作者 Yue-Yang Liu Ke Feng Hui Wang Dan-wei Zhang wei zhou Gang Zhao Jiaheng Zhang Zhan-Ting Li 《Chinese Chemical Letters》 2025年第9期350-354,共5页
The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of mol... The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of molecular vips.However,its moderate water solubility limits broader application.Here we report the synthesis of three CB[7]derivatives M1-M3 by modifying an average of 4.2,5.5,and 5.9 sulfonatopropoxy groups onto their"equator"carbons.Compared to CB[7],their water-solubility increased by at least 26.6-,23.6-,and 19.2-fold,respectively,while the maximum tolerated doses(MTD)of M1 and M2 improved by 2.5-and 2.3-fold.Phase solubility diagram studies demonstrate that M1 and M2 significantly enhance the water-solubility of eighteen poorly soluble drugs.In vivo experiments in rat complete Freund's arthritis reveal that M1 not only improves the anti-inflammatory efficacy of indomethacin by up to 52%,but also substantially reduces its side effect of gastric ulcer. 展开更多
关键词 uril SOLUBILIZATION EXCIPIENT Host-vip chemistry Molecular container INDOMETHACIN
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Evaluation of two algorithms measuring homologous recombination deficiency status in prognostic assessment for treatment-naive non-small cell lung cancer 被引量:1
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作者 Yidan Ma Jingyu Huang +13 位作者 Lei He Jun Du Longteng Liu Xiaoguang Li Peng Jiao Xiaonan Wu wei zhou Xiaomao Xu Li Yang Jing Di Changbin Zhu Lin Li Dongge Liu Zheng Wang 《Chinese Journal of Cancer Research》 2025年第3期352-364,共13页
Objective:Patients with homologous recombination deficiency(HRD)demonstrate distinct clinicopathological and prognostic features.However,standardised and clinically validated HRD detection methodologies specifically t... Objective:Patients with homologous recombination deficiency(HRD)demonstrate distinct clinicopathological and prognostic features.However,standardised and clinically validated HRD detection methodologies specifically tailored for non-small cell lung cancer(NSCLC)have yet to be established.Further research is needed to clarify the precise role and clinical implications of HRD in NSCLC.Methods:A cohort of 580 treatment-naive NSCLC patients was retrospectively enrolled.Comprehensive genomic profiling(CGP)was performed for all patients,and HRD status was evaluated using two genomic scar score(GSS)-based algorithms:a machine learning-based GSS(ML-GSS)and a continuous linear regression-based GSS(CLR-GSS).To assess the diagnostic performance(sensitivity and specificity)of the ML-GSS and CLR-GSS algorithms for HRD detection,immunohistochemical(IHC)staining was conducted for two HRD-related biomarkers:Schlafen 11(SLFN11)and RAD51.Survival analysis,including progression-free survival(PFS),along with multivariable Cox proportional hazards models,was performed to compare the prognostic value of the two HRD algorithms.Results:Among all patients,146(25.2%)and 46(7.9%)were classified as HRD-positive(HRD+)by ML-GSS and CLR-GSS,respectively.Using SLFN11 IHC expression as the reference standard,comparative analysis demonstrated that ML-GSS exhibited significantly higher sensitivity but lower specificity than CLR-GSS.This trend was consistently observed in RAD51 staining analysis.Compared to HRD-negative(HRD-)patients,MLGSS-defined HRD+cases displayed distinct clinicopathological and genomic features,including a higher prevalence of homologous recombination(HR)-related genes mutations,BRCA1/2 mutations,TP53 mutations,elevated tumor mutation burden(TMB),and increased copy number variations(CNVs).In contrast,CLR-GSSdefined HRD+patients were only enriched for BRCA1/2 mutations,TP53 mutations,and elevated TMB.Furthermore,ML-GSS-defined HRD+status was associated with significantly worse prognosis following first-line therapy compared to HRD-patients.Univariate and multivariable Cox analyses identified ML-GSS-defined HRD+and TP53 mutations as significant predictors and independent risk factors,respectively.No such associations were observed in the CLR-GSS-defined HRD+cohort.Conclusions:ML-GSS demonstrated superior performance to CLR-GSS in assessing chromosomal instability(CIN)and showed greater clinical utility.We recommend the ML-GSS algorithm as a robust and clinically validated tool for HRD/CIN evaluation in NSCLC.Furthermore,ML-GSS-defined HRD+status was identified as both a significant predictor and an independent risk factor. 展开更多
关键词 Non-small cell lung cancer homologous recombination deficiency methodology TP53 PROGNOSIS
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Misorientation and dislocation evolution in rapid residual stress relaxation by electropulsing 被引量:1
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作者 Ayan Bhowmik Jin Lee Tan +5 位作者 Yongjing Yang Aprilia Aprilia Nicholas Chia Paul Williams Martyn Jones wei zhou 《Journal of Materials Science & Technology》 2025年第6期292-299,共8页
This study investigates the effect of high current density electropulsing on the material in a rapid stress relaxation process.An AISI 1020 steel was shot-peened to induce surface compressive residual stresses in a co... This study investigates the effect of high current density electropulsing on the material in a rapid stress relaxation process.An AISI 1020 steel was shot-peened to induce surface compressive residual stresses in a controlled manner and subsequently electropulsed to investigate the changes in microstructure and defect configuration.AISI 1020 steel was chosen as it has a simple microstructure(plain ferritic)and composition with low alloying conditions.It is an appropriate material to study the effect of trans-mitting electric pulses on the microstructural defect evolution.A combination of electron-backscattered diffraction and transmission electron microscopy proved to be an effective tool in characterizing the post-electropulsing effects critically.By application of electropulsing,a reduction in the surface residual stress layer was noticed.Also,reductions in misorientation and dislocation density together with the disentan-glement of dislocations within the cold-worked layer were observed after electropulsing.Additionally,the annihilation of shot-peening-induced deformation bands beyond the residual layer depth was observed.These effects have been rationalised by taking into account the various possibilities of athermal effects of electropulsing. 展开更多
关键词 ELECTROPULSING Residual stress MISORIENTATION Dislocation annihilation TEM
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Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape 被引量:1
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作者 Xuewei Zhang wei zhou +13 位作者 Yuming Huang Liang Xie Tonghui Li Huimin Kang Lijie Wang Yang Yu Yani Ding Junfeng Li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao Meng Jihui Gao Guangbo Zhao 《Journal of Energy Chemistry》 2025年第1期201-214,共14页
The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for... The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for hydrogen production.Despite remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable obstacle.This impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles detachment.To address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis system.Compared to constant voltage electrolysis(hydrogen production rate:51.6 m L h^(-1),energy consumption:5.37 kWh Nm-^(3)H_(2)),this strategy(hydrogen production rate:66 m L h^(-1),energy consumption:3.83 kWh Nm-^(3)H_(2))increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic(PV)system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 V.The combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis(PDE)dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode surface.As such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport processes.This promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors. 展开更多
关键词 Water electrolysis Hydrogen production Pulsed dynamic electrolysis Proton exchange membrane water electrolysis Mass transport
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A novel carrier interleaved PWM method for four-level nested neutralpoint-clamped inverters 被引量:1
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作者 wei zhou Jupeng Pang +3 位作者 Mingzhe Wu Chao Wang Kui Wang Yongdong Li 《iEnergy》 2025年第1期65-76,共12页
The four-level nested neutral-point-clamped(4L-NNPC)inverter is a competitive topology among the various medium-voltage multilevel converters,and its main issue is flying-capacitor voltage unbalance.In this article,a ... The four-level nested neutral-point-clamped(4L-NNPC)inverter is a competitive topology among the various medium-voltage multilevel converters,and its main issue is flying-capacitor voltage unbalance.In this article,a novel carrier-interleaved pulse width modulation(CIPWM)method that satisfies the volt-sec balance principle is proposed with an advanced carrier distribution rule.By adopting the proposed CIPWM method,the redundant switching states of 4L-NNPC inverters can be evenly distributed into the output PWM waveform in each carrier period,and natural flying-capacitor voltage balance can be achieved.Furthermore,an active balancing strategy is also proposed to eliminate the voltage unbalance caused by nonideal factors,which is realized by simply adjusting the duty cycle and with no need to adjust the redundant switching states for 4L-NNPC inverters.The simulation and experimental results verify the effectiveness of the proposed CIPWM method and the flying-capacitor voltage balancing strategy. 展开更多
关键词 Multilevel converters capacitor voltage balance pulse width modulation
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Masquelet technique using an allogeneic cortical bone graft for a large bone defect:A case report
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作者 Hai-Yang Zong Yu Liu +2 位作者 Xing Yin wei zhou Nan Li 《World Journal of Clinical Cases》 SCIE 2025年第5期36-43,共8页
BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of th... BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of the radius associated with a 9 cm bone defect,which was filled with a large allogeneic cortical bone graft from a bone bank.Complete bony union was achieved after 14 months of follow-up.Previous studies have used autogenous bone as the primary bone source for the Masquelet technique;in our case,the exclusive use of allografts is as successful as the use of autologous bone grafts.With the advent of bone banks,it is possible to obtain an unlimited amount of allograft,and the Masquelet technique may be further improved based on this new way of bone grafting.CASE SUMMARY In this study,we reported a case of repair of a long bone defect in a 40-year-old male patient,which was characterized by the utilization of allograft cortical bone combined with the Masquelet technique for the treatment of the patient's long bone defect in the forearm.The patient's results of functional recovery of the forearm were surprising,which further deepens the scope of application of Masquelet technique and helps to strengthen the efficacy of Masquelet technique in the treatment of long bones indeed.CONCLUSION Allograft cortical bone combined with the Masquelet technique provides a new method of treatment to large bone defect. 展开更多
关键词 OSTEOMYELITIS Bone defect Allogeneic cortical bone Masquelet technique Membrane induction technique Case report
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生态移民的环境影响研究——以广西移民迁入区为例(英文) 被引量:4
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作者 Ye-cui HU wei zhou Tao YUAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2018年第3期240-254,共15页
目的:生态移民在改善迁出区生态环境的同时,也改变了迁入区资源环境配置格局。客观评价大量生态移民涌入给迁入区造成的生态系统压力,对生态移民政策的可持续推进及新形式下解决脱贫和生态环境保护问题有重要意义。创新点:从微观农户尺... 目的:生态移民在改善迁出区生态环境的同时,也改变了迁入区资源环境配置格局。客观评价大量生态移民涌入给迁入区造成的生态系统压力,对生态移民政策的可持续推进及新形式下解决脱贫和生态环境保护问题有重要意义。创新点:从微观农户尺度,采用生产性生态足迹评价移民迁入区生态移民工程的生态环境影响。方法:1.基于参与式农户调查方法,获取移民迁入区移民和当地驻民的生态足迹账户、土地利用及农户家庭等基本信息;2.采用生产性生态足迹评价移民迁入区生态移民工程的生态环境影响;3.构建"STIRPAT"模型,分析移民迁入区生态环境变化的影响因素。结论:1.大规模移民的迁入对移民安置区的生态环境造成持续压力;2.人口规模扩大、荒草地开垦以及消费需求增长是造成移民迁入区生态环境压力的主要原因;3.合理测算移民迁入区人口承载力、促进农户生计转型和增加农户生计多样化可以有效缓解生态移民对生态环境的巨大压力。 展开更多
关键词 生态移民 生态足迹 移民迁入区 广西
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