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Copper-substituted P3-type Na_(0.54)Mn_(0.64)Fe_(_(0.1)6)Mg_(0.1)Cu_(0.1)O_(2) cathode material for sodium-ion batteries with enhanced anionic redox reversibility
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作者 Zhe Mei Xun-Lu Li +10 位作者 Cui Ma Jie Zeng Chong-Yu Du Rui-Jie Luo Xuan Xu Zhe Qian Zi-Ting Zhou Ya Zhang Qian Cheng Yao-Guo Fang Yong-Ning Zhou 《Rare Metals》 2025年第5期2986-2996,共11页
P3-type manganese-iron-based cathodes with high specific capacity and abundant resource have attracted considerable attention for sodium-ion batteries.However,the long-term cycle stability of P3-type cathodes is still... P3-type manganese-iron-based cathodes with high specific capacity and abundant resource have attracted considerable attention for sodium-ion batteries.However,the long-term cycle stability of P3-type cathodes is still not satisfactory.In this work,we design a new quaternary manganese-iron-based cathode material(P3-Na_(0.54)Mn_(0.64)Fe_(_(0.1)6)Mg_(0.1)Cu_(0.1)O_(2))by Cu substitution.The strong covalent Cu-O bonds improve the structural stability and the reversibility of O redox during charge and discharge processes.Cu substitution also mitigates the structure change with less unit cell volume variation,and improves the Na-ion transport kinetics effectively.As a result,NMFMC delivers much improved cycling stability and rate capability compared with NMFM.It reveals that the charge compensation of NMFMC is mainly contributed by Mn^(3+/4+),Fe^(3+/3.5+)and O_(2-/-)during the charge and discharge processes,and Cu substitution can also enhance the activity and reversibility of Fe redox.This strategy provides a new pathway toward improving the stability and O redox reversibility of P3-type cathode materials for sodium-ion batteries. 展开更多
关键词 Sodium-ion batteries Cathode materials Cu substitution Anionic redox reversibility
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猫杯状病毒感染性克隆的构建及拯救病毒的鉴定
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作者 朱雪敏 李鑫基 +7 位作者 华炯钢 陈柳 叶伟成 张传亮 朱寅初 付媛 张存 云涛 《中国兽医科学》 北大核心 2026年第1期20-26,共7页
旨在建立猫杯状病毒(FCV)反向遗传系统,以探究FCV的致病机制,为后续疫苗研发提供科学依据。以FCV HZ2024株为对象,构建DNA-launched感染性克隆系统。FCV全基因组的4个片段被依次插入pAY-CHS重组质粒后转染F81细胞并传代鉴定。结果显示,F... 旨在建立猫杯状病毒(FCV)反向遗传系统,以探究FCV的致病机制,为后续疫苗研发提供科学依据。以FCV HZ2024株为对象,构建DNA-launched感染性克隆系统。FCV全基因组的4个片段被依次插入pAY-CHS重组质粒后转染F81细胞并传代鉴定。结果显示,FCV HZ2024基因片段扩增后插入DNA-launched系统质粒,成功构建DNA-launched系统拯救病毒rFCV HZ2024-RE,转染细胞24 h后出现细胞病变效应,病毒滴度稳定在10^(7)~10^(8T)CID_(50)/m L。间接免疫荧光检测证实VP1蛋白抗原表位完全保留,重组病毒的衣壳蛋白成功表达。且重组病毒与亲本毒株的复制动力学高度相似,蚀斑形态无显著差异。Eco R V酶切及测序验证表明,突变位点(C7183T、A7186C)被精准引入且稳定遗传。总之,构建的DNA-launched系统实现了FCV高效拯救与精准遗传。 展开更多
关键词 猫杯状病毒 感染性克隆 反向遗传学 病毒拯救
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考虑动态裂缝扩展的致密油藏不稳定注水方法
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作者 黄博 程妮 +5 位作者 夏晨丹 魏梦园 汪洋 谭洪超 程时清 蔡玎宁 《断块油气田》 北大核心 2026年第1期139-146,共8页
由于致密油藏储层物性差,开发过程中油井产量低、递减快,采用注水补充能量开发,含水率上升快,稳油控水难度大。文中针对某长8段致密油藏水驱后部分油井水淹、稳产难度大等问题,建立了致密油藏复杂缝网多尺度非线性渗流模型。大量模拟计... 由于致密油藏储层物性差,开发过程中油井产量低、递减快,采用注水补充能量开发,含水率上升快,稳油控水难度大。文中针对某长8段致密油藏水驱后部分油井水淹、稳产难度大等问题,建立了致密油藏复杂缝网多尺度非线性渗流模型。大量模拟计算发现:注水诱导裂缝从注水井附近开始向外扩展,延伸过程中向天然裂缝偏转,然后沟通天然裂缝,最后沟通生产井,导致裂缝水窜。注入压力、注入量、最大主应力方向等影响诱导裂缝的规模及延伸长度,引入动态裂缝面积比的概念评价因裂缝扩展而增大的水驱波及程度。建立了动态裂缝扩展数值模拟方法,应用于致密油藏不稳定注水方法论证,对比分析了正反阶梯注水、周期注水、水平井同井分段注水等不稳定水驱的开发指标。结果表明:某长8段致密油藏可采用井排距为260 m×120 m的菱形反九点注采井网。反阶梯注水效果较好,建议初期注入压力适度大于裂缝开启压力,油井降低产液量或关井,当诱导裂缝接近油井时,注入压力要小于裂缝开启压力;同时,推荐长注短停的注水工作制度和水平井同井分段注采方案。 展开更多
关键词 致密油藏 动态裂缝 数值模拟 不稳定注水 反阶梯注水
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基于一阶速度-应力方程的起伏地表VTI介质逆时偏移
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作者 张凯 郭林杰 +3 位作者 李振春 丁易 李壮 蒋忠 《石油物探》 北大核心 2026年第1期77-87,共11页
随着油气勘探开发的深入,目标探区呈现复杂地表和复杂构造的双复杂特征,鉴于地表高程变化大和研究重点聚焦于小尺度勘探目标的因素,具有垂直对称轴的横向各向同性(VTI)介质被广泛应用于复杂地质构造的叠前偏移成像中,这些因素都会改变... 随着油气勘探开发的深入,目标探区呈现复杂地表和复杂构造的双复杂特征,鉴于地表高程变化大和研究重点聚焦于小尺度勘探目标的因素,具有垂直对称轴的横向各向同性(VTI)介质被广泛应用于复杂地质构造的叠前偏移成像中,这些因素都会改变波的传播性质,使得成像方法难以满足高精度成像的需求。为了精确模拟VTI介质的起伏地表下的波场传播特征,将流体力学中的正交贴体网格引入起伏地表下VTI介质的网格剖分中,发展了一套基于起伏地表VTI介质的全交错有限差分模拟算法。并基于正演模拟算法,改进了起伏地表问题下的逆时偏移成像方法。数值模拟结果表明,所发展的模拟方法可以正确模拟起伏地表下VTI介质中的波场传播,并在此基础上进行高精度的RTM成像,成像结果相比于各向同性假设或者规则网格假设下的RTM,更准确地反映了反射面所在的位置,降低了起伏地表对成像结果的影响。 展开更多
关键词 贴体网格 起伏地表 VTI介质逆时偏移 伪声波方程
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中国原地浸出采铀发展史——第三部分:技术进步,创新发展
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作者 王海峰 《有色金属(冶炼部分)》 北大核心 2026年第1期160-173,共14页
地浸采铀技术从无到有已完全成熟,并进入创新发展阶段。但在几十年的地浸采铀试验和生产中科技人员发现,中国矿山钻孔抽注液量和浸出液铀浓度普遍偏低、人均劳动生产率有待提高以及矿山经济效果不理想。为解决这些问题,探寻地浸采铀新... 地浸采铀技术从无到有已完全成熟,并进入创新发展阶段。但在几十年的地浸采铀试验和生产中科技人员发现,中国矿山钻孔抽注液量和浸出液铀浓度普遍偏低、人均劳动生产率有待提高以及矿山经济效果不理想。为解决这些问题,探寻地浸采铀新工艺、新方法和开创企业发展生机,他们在钻孔施工、成井和洗井工艺、地下浸出方法、水冶工艺、环境保护和污染控制等方面提出并践行一个又一个新思路、新技术。正是这种执着奋进,敢想敢干的精神,完善了中国地浸采铀工艺,推动了地浸采铀的技术进步。实践证明,新技术的追求永无止境,而“技术进步,创新发展”永远是地浸采铀的命脉。 展开更多
关键词 反渗透 淋萃流程 探采结合 分布式
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基于系统反向泄漏的高阻隔性薄膜透气性测试模型与特性
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作者 刘孝锋 苏志从 +2 位作者 胡宝法 庄加福 褚若波 《包装工程》 北大核心 2026年第1期31-37,共7页
目的为提高塑料薄膜和薄片等食药品软包装材料氧气阻隔性的检测精度,简化实际的透气性测试而提高测试效益。方法把系统反向泄漏和气体渗透视为分子流状态,根据气量守恒和流阻不变性,建立具有外层辅助密封室和反向泄漏的高阻隔性软包装... 目的为提高塑料薄膜和薄片等食药品软包装材料氧气阻隔性的检测精度,简化实际的透气性测试而提高测试效益。方法把系统反向泄漏和气体渗透视为分子流状态,根据气量守恒和流阻不变性,建立具有外层辅助密封室和反向泄漏的高阻隔性软包装材料透气性测试数学模型,得出透气性测试系统内、外层密封室压强和漏率变化特性,给出反向泄漏测试系统等效测试时间表达式。结果具有外层辅助密封室的透气性测试系统等效测试时间远大于24h,透气性测试相对误差约为1.35%。结论具有外层辅助密封室的透气性测试装置测试,其测试结果与忽略系统泄漏的理想测试结果比较,误差可忽略,无需进行系统泄漏测量和测试校正,准确测出氧气阻隔性。为高阻隔性薄膜透气性高精高效测试提供理论依据。 展开更多
关键词 系统反向泄漏 氧气阻隔性 分子流状态 透气性测试 等效测试时间
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从轻罪“治罪”到轻罪“治理”:定罪免刑的体系化建构
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作者 李翔 周家琳 《山东大学学报(哲学社会科学版)》 北大核心 2026年第1期191-202,共12页
轻罪扩张虽然具有合理性,但也存在伴生风险。纾解轻罪扩张伴生风险,需要体系化构建定罪免刑制度。定罪免刑的正当性依据来源于两方面:其一,有罪可以不罚的原因是,如果被犯罪行为所破坏的社会关系能够借助其他手段得以恢复,意味着行为缺... 轻罪扩张虽然具有合理性,但也存在伴生风险。纾解轻罪扩张伴生风险,需要体系化构建定罪免刑制度。定罪免刑的正当性依据来源于两方面:其一,有罪可以不罚的原因是,如果被犯罪行为所破坏的社会关系能够借助其他手段得以恢复,意味着行为缺乏需罚性,裁判规范的全部启动不是必需的。其二,不罚也需要定罪的原因是,对行为规范效力的恢复,可以不依赖于刑罚的启动,但是不能脱离定罪宣告。对轻罪犯罪人适用定罪免刑,并不意味着同时必然免除行政责任的承担。此时,需要构建起专属于轻罪案件审判阶段的行刑反向衔接机制。为了避免定罪宣告成为一种“前科刑”,需要对定罪附随后果进行区分设计。应废除针对微罪的所有报应性附随后果,并对微罪犯罪人的被遗忘权进行特殊保护,以构建完整的犯罪记录封存制度。 展开更多
关键词 定罪免刑 轻罪治理 行刑反向衔接 犯罪记录封存
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基于因子与聚类分析的多囊卵巢综合征中医证候分布规律研究
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作者 戴金芳 俞康 +3 位作者 李温珏 卢君 钟素琴 梁瑞宁 《中医药信息》 2026年第2期53-59,共7页
目的基于多中心大样本数据解析多囊卵巢综合征(PCOS)中医证候分布规律,构建病机分型框架,为临床精准辨证提供依据。方法采用多中心横断面研究设计,纳入7家三甲医院936例PCOS患者,通过文献挖掘和德尔菲法专家咨询制定标准化中医证候问卷... 目的基于多中心大样本数据解析多囊卵巢综合征(PCOS)中医证候分布规律,构建病机分型框架,为临床精准辨证提供依据。方法采用多中心横断面研究设计,纳入7家三甲医院936例PCOS患者,通过文献挖掘和德尔菲法专家咨询制定标准化中医证候问卷,运用频数分析提取核心症状,因子分析明确证候要素,K-均值聚类归纳核心证型。结果高频症状以腰膝酸软、肌肤油腻、情绪抑郁善叹息、痤疮为主;病位证素以肾、肺/大肠、冲脉为核心,病性证素以湿热、血瘀、阴虚为关键;聚类分析确定五大证型:肾阴虚湿热证、脾虚痰湿证、气滞血瘀证、湿热瘀阻证、肾阳虚痰湿证,覆盖97.86%病例。结论本研究确立了PCOS以肾阴虚湿热、脾虚痰湿、气滞血瘀、湿热瘀阻、肾阳虚痰湿证为主的五大核心证型,为证型规范化提供了数据支撑,同时,病位证素“冲脉”“肺/大肠”在PCOS病机中的重要性需予以重视。 展开更多
关键词 多囊卵巢综合征 中医证候 病机 冲脉逆盛 因子分析 聚类分析
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逆向代际经济支持对家庭人力资本投资的影响
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作者 穆怀中 魏仕弼 王延辉 《沈阳师范大学学报(社会科学版)》 2026年第1期47-55,共9页
基于2022年中国家庭追踪调查(CFPS)数据资料,实证分析了祖辈逆向代际经济支持对家庭教育支出的影响及作用机制。研究发现:逆向代际经济支持显著促进了家庭教育支出,父母教育期望在逆向代际经济支持影响家庭教育支出过程中起中介作用,逆... 基于2022年中国家庭追踪调查(CFPS)数据资料,实证分析了祖辈逆向代际经济支持对家庭教育支出的影响及作用机制。研究发现:逆向代际经济支持显著促进了家庭教育支出,父母教育期望在逆向代际经济支持影响家庭教育支出过程中起中介作用,逆向代际经济支持对家庭教育支出的促进作用在城乡和不同收入水平的家庭之间存在异质性。加大对基础教育的政策支持力度、提高农村地区和低收入家庭的收入水平,有助于增强家庭人力资本投资。同时,还需要解决由于信息鸿沟等原因导致的父母教育期望不足问题。 展开更多
关键词 逆向代际经济支持 父母教育期望 家庭人力资本投资
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行刑反向衔接若干疑难问题与破解
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作者 翁武耀 张雨乔 《河南社会科学》 北大核心 2026年第1期75-86,共12页
实践中,行刑非法证据排除规则存在不合理差异、行政处罚追责期限的计算方式不明确、裁量情节的适用范围过窄等问题,导致行刑反向衔接制度在证据转化审查、追责期限计算、裁量情节适用等方面存在较大争议和困惑。在刑事证据转化为行政证... 实践中,行刑非法证据排除规则存在不合理差异、行政处罚追责期限的计算方式不明确、裁量情节的适用范围过窄等问题,导致行刑反向衔接制度在证据转化审查、追责期限计算、裁量情节适用等方面存在较大争议和困惑。在刑事证据转化为行政证据时,有必要依据行政非法证据排除规则审查证据合法性,同时通过完善刑事非法实物证据排除规则消除行刑非法证据规则的不合理差异,避免刑事程序中可采取的证据在行政程序中被排除的矛盾。在计算行政处罚追责期限时,“发现违法行为”的主体应为有权追责的国家机关,包括司法机关,应以启动调查、取证或立案程序为“发现违法行为”的依据,无需引入追责期限的中断或中止制度。在适用裁量情节时,应扩大行政法律中规定的法定裁量情节范围,增设酌定减免处罚条款,允许在特殊情况下基于个案正义减免行政处罚。对于同一裁量情节的重复适用,原则上应禁止,但在出现“行刑倒挂”的情形下,可例外地允许重复适用裁量情节,以实现过罚相当。 展开更多
关键词 行刑反向衔接 证据合法性审查 行政处罚追责期限 裁量情节 税收法治
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Regulation of dendrite and axon growth and arborization by CD40L-reverse signaling:Interrelationships among JNK,PKC,and ERK1/2 signaling pathways
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作者 Paulina Carriba 《Neural Regeneration Research》 2026年第3期1116-1117,共2页
The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the cent... The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the central determinant of the functional properties of neurons and neural circuits.The topological and structural morphology of axons and dendrites defines and determines how synapses are conformed.The morphological diversity of axon and dendrite arborization governs the neuron’s inputs,synaptic integration,neuronal computation,signal transmission,and network circuitry,hence defining the particular connectivity and function of the different brain areas. 展开更多
关键词 CD L dendrite growth dendrite arborization nervous system neural architecturethe reverse signaling PKC JNK
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Potential and value of rescuing dying neurons
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作者 Wenting You Tos T.J.M.Berendschot +3 位作者 Birke J.Benedikter Carroll A.B.Webers Chris P.M.Reutelingsperger Theo G.M.F.Gorgels 《Neural Regeneration Research》 2026年第3期1013-1022,共10页
Unwarranted death of neurons is a major cause of neurodegenerative diseases.Since mature neurons are postmitotic and do not replicate,their death usually constitutes an irreversible step in pathology.A logical strateg... Unwarranted death of neurons is a major cause of neurodegenerative diseases.Since mature neurons are postmitotic and do not replicate,their death usually constitutes an irreversible step in pathology.A logical strategy to prevent neurodegeneration would then be to save all neurons that are still alive,i.e.protecting the ones that are still healthy as well as trying to rescue the ones that are damaged and in the process of dying.Regarding the latter,recent experiments have indicated that the possibility of reversing the cell death process and rescuing dying cells is more significant than previously anticipated.In many situations,the elimination of the cell death trigger alone enables dying cells to spontaneously repair their damage,recover,and survive.In this review,we explore the factors,which determine the fate of neurons engaged in the cell death process.A deeper insight into cell death mechanisms and the intrinsic capacity of cells to recover could pave the way for novel therapeutic approaches to neurodegenerative diseases. 展开更多
关键词 APOPTOSIS dying neurons neuronal recovery neurorescue reversible cell death process
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A Q-Learning Improved Particle Swarm Optimization for Aircraft Pulsating Assembly Line Scheduling Problem Considering Skilled Operator Allocation
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作者 Xiaoyu Wen Haohao Liu +6 位作者 Xinyu Zhang Haoqi Wang Yuyan Zhang Guoyong Ye Hongwen Xing Siren Liu Hao Li 《Computers, Materials & Continua》 2026年第1期1503-1529,共27页
Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in oper... Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in operator workloads and significantly increase the complexity of scheduling.To address this challenge,this study investigates the Aircraft Pulsating Assembly Line Scheduling Problem(APALSP)under skilled operator allocation,with the objective of minimizing assembly completion time.A mathematical model considering skilled operator allocation is developed,and a Q-Learning improved Particle Swarm Optimization algorithm(QLPSO)is proposed.In the algorithm design,a reverse scheduling strategy is adopted to effectively manage large-scale precedence constraints.Moreover,a reverse sequence encoding method is introduced to generate operation sequences,while a time decoding mechanism is employed to determine completion times.The problem is further reformulated as a Markov Decision Process(MDP)with explicitly defined state and action spaces.Within QLPSO,the Q-learning mechanism adaptively adjusts inertia weights and learning factors,thereby achieving a balance between exploration capability and convergence performance.To validate the effectiveness of the proposed approach,extensive computational experiments are conducted on benchmark instances of different scales,including small,medium,large,and ultra-large cases.The results demonstrate that QLPSO consistently delivers stable and high-quality solutions across all scenarios.In ultra-large-scale instances,it improves the best solution by 25.2%compared with the Genetic Algorithm(GA)and enhances the average solution by 16.9%over the Q-learning algorithm,showing clear advantages over the comparative methods.These findings not only confirm the effectiveness of the proposed algorithm but also provide valuable theoretical references and practical guidance for the intelligent scheduling optimization of aircraft pulsating assembly lines. 展开更多
关键词 Aircraft pulsating assembly lines skilled operator reinforcement learning PSO reverse scheduling
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A Reconfigurable Omnidirectional Triboelectric Whisker Sensor Array for Versatile Human–Machine–Environment Interaction
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作者 Weichen Wang Jiaqi Zhu +9 位作者 Hongfa Zhao Fei Yao Yuzhu Zhang Xiankuan Qian Mingrui Shu Zhigang Wu Minyi Xu Hongya Geng Wenbo Ding Juntian Qu 《Nano-Micro Letters》 2026年第3期121-140,共20页
Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations... Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations remain in unit-level reconfiguration,multiaxial force and motion sensing,and robust operation across dynamically changing or irregular surfaces.Herein,we develop a reconfigurable omnidirectional triboelectric whisker sensor array(RO-TWSA)comprising multiple sensing units that integrate a triboelectric whisker structure(TWS)with an untethered hydro-sealing vacuum sucker(UHSVS),enabling reversibly portable deployment and omnidirectional perception across diverse surfaces.Using a simple dual-triangular electrode layout paired with MXene/silicone nanocomposite dielectric layer,the sensor unit achieves precise omnidirectional force and motion sensing with a detection threshold as low as 0.024 N and an angular resolution of 5°,while the UHSVS provides reliable and reversible multi-surface anchoring for the sensor units by involving a newly designed hydrogel combining high mechanical robustness and superior water absorption.Extensive experiments demonstrate the effectiveness of RO-TWSA across various interactive scenarios,including teleoperation,tactile diagnostics,and robotic autonomous exploration.Overall,RO-TWSA presents a versatile and high-resolution tactile interface,offering new avenues for intelligent perception and interaction in complex real-world environments. 展开更多
关键词 Reconfigurable sensor array Interaction interface Tactile perception Omnidirectional sensor Reversible anchoring
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Outcomes of reverse vs anatomic total shoulder arthroplasty in glenohumeral osteoarthritis without rotator cuff deficiency:A metaanalysis
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作者 Clevio Desouza Isteyaque Siddique +1 位作者 Kishan Kushwaha Anoop Puri 《World Journal of Orthopedics》 2026年第1期164-177,共14页
BACKGROUND The optimal surgical approach for patients with primary glenohumeral osteoarthritis(GHOA)and an intact rotator cuff remains debated.While anatomic total shoulder arthroplasty(TSA)has traditionally been favo... BACKGROUND The optimal surgical approach for patients with primary glenohumeral osteoarthritis(GHOA)and an intact rotator cuff remains debated.While anatomic total shoulder arthroplasty(TSA)has traditionally been favoured,reverse TSA(RTSA)is increasingly utilized.AIM To systematically compare the outcomes of RTSA and TSA in this specific patient population.METHODS A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines.Retrospective comparative studies evaluating RTSA and TSA in patients with GHOA and intact rotator cuff were included.Key outcomes assessed included complication and reoperation rates,patient-reported outcome measures(PROMs),and range of motion.Risk of bias was assessed using the Risk of Bias in Non-randomized Studies of Interventions tool.RESULTS Twelve studies encompassing 1608 patients(580 RTSA,1028 TSA)met inclusion criteria.RTSA was associated with a lower reoperation rate compared to TSA[odds ratio=0.37;95%confidence interval(CI):0.14-0.94;P value=0.04],while no significant difference in overall complication rates was observed(odds ratio=0.47;95%CI:0.19-1.16;P value=0.10).RTSA patients showed superior outcomes in University of California Los Angeles,Simple Shoulder Test,and Shoulder Pain and Disability Index scores;however,the differences did not exceed the minimal clinically important difference.TSA patients had significantly better external rotation(mean difference=-9.0°;95%CI:-13.21 to-5.02;P value<0.0001).No significant differences were found in other range of motion measures or satisfaction scores.The overall methodological quality of included studies was moderate to serious.CONCLUSION In patients with GHOA and an intact rotator cuff,RTSA may offer comparable or improved outcomes to TSA with lower reoperation rates and similar complication profiles.Functional outcomes favour RTSA in certain patientreported outcome measures,while TSA retains an advantage in external rotation.Surgical decision-making should remain individualized based on patient characteristics and functional demands. 展开更多
关键词 Reverse shoulder arthroplasty Total shoulder arthroplasty Glenohumeral osteoarthritis Intact rotator cuff Metaanalysis
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Enhanced Capacity Reversible Data Hiding Based on Pixel Value Ordering in Triple Stego Images
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作者 Kim Sao Nguyen Ngoc Dung Bui 《Computers, Materials & Continua》 2026年第1期1571-1586,共16页
Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi... Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi-stego images provides good image quality but often results in low embedding capability.To address these challenges,this paper proposes a high-capacity RDH scheme based on PVO that generates three stego images from a single cover image.The cover image is partitioned into non-overlapping blocks with pixels sorted in ascending order.Four secret bits are embedded into each block’s maximum pixel value,while three additional bits are embedded into the second-largest value when the pixel difference exceeds a predefined threshold.A similar embedding strategy is also applied to the minimum side of the block,including the second-smallest pixel value.This design enables each block to embed up to 14 bits of secret data.Experimental results demonstrate that the proposed method achieves significantly higher embedding capacity and improved visual quality compared to existing triple-stego RDH approaches,advancing the field of reversible steganography. 展开更多
关键词 RDH reversible data hiding PVO RDH base three stego images
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回火温度对1100 MPa级超高强钢组织与性能的影响
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作者 董敬文 王天琪 +3 位作者 弓硕 贾涓 柴希阳 罗小兵 《金属热处理》 北大核心 2026年第1期159-166,共8页
以控轧控冷(TMCP)+回火(T)工艺制备的低碳超高强钢为研究对象,采用扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、拉伸试验和冲击试验等方法,系统研究了回火温度(500、550和600℃)对1100 MPa级超高强钢微观组织、纳米相析出和力学性... 以控轧控冷(TMCP)+回火(T)工艺制备的低碳超高强钢为研究对象,采用扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、拉伸试验和冲击试验等方法,系统研究了回火温度(500、550和600℃)对1100 MPa级超高强钢微观组织、纳米相析出和力学性能的影响。结果表明,相较于TMCP态,500℃回火后,屈服强度和抗拉强度分别上升至1173 MPa和1276 MPa,-20℃和-84℃冲击吸收能量下降至107 J和55 J。随回火温度升高,屈服强度先增加后降低,抗拉强度逐渐降低,低温韧性逐渐增强。TMCP态试验钢的组织为板条马氏体,回火后组织为回火马氏体。500~600℃回火条件下,试验钢中形成细小的NiAl纳米相及逆转变奥氏体,纳米相的析出强化作用和逆转变奥氏体的增韧作用对强韧性匹配产生重要影响。在600℃回火条件下获得良好的强韧性匹配,其屈服强度为1160 MPa,抗拉强度为1212 MPa,-20℃和-84℃冲击吸收能量为199 J和194 J。 展开更多
关键词 超高强钢 逆转变奥氏体 NiAl析出相 强韧性
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Construction of MMC-CLCC Hybrid DC Transmission System and Its Power Flow Reversal Control Strategy
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作者 Yechun Xin Xinyuan Zhao +3 位作者 Dong Ding Shuyu Chen Chuanjie Wang Tuo Wang 《Energy Engineering》 2026年第1期460-474,共15页
To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hyb... To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process. 展开更多
关键词 Hybrid HVDC transmission modular multilevel converter(MMC) controllable line commutated converter(CLCC) online power flow reversal full-bridge and half-bridge submodules new energy through dc transmission system
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圆形网格抽样和逆近邻优化的密度峰值聚类算法
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作者 赵嘉 何超凡 +2 位作者 肖人彬 曹浩 樊棠怀 《工程科学学报》 北大核心 2026年第1期161-176,共16页
密度峰值聚类(DPC)算法是一种简单高效的聚类算法,因其可直观和快速发现数据集中的类簇而得到广泛关注.但DPC算法需计算所有样本间的欧氏距离,算法的时间复杂度较高;局部密度定义未考虑类簇间密度差异影响,易误选类簇中心;使用链式分配... 密度峰值聚类(DPC)算法是一种简单高效的聚类算法,因其可直观和快速发现数据集中的类簇而得到广泛关注.但DPC算法需计算所有样本间的欧氏距离,算法的时间复杂度较高;局部密度定义未考虑类簇间密度差异影响,易误选类簇中心;使用链式分配策略,易产生错误连带效应.因此,本文提出一种圆形网格抽样和逆近邻优化的密度峰值聚类算法.该算法采用圆形网格抽样得到代表以减少需要计算的样本数,降低算法计算的时间开销,并引入近似K近邻策略加强代表和初始样本的联系,减少抽样导致的聚类精度丢失;利用逆近邻优化局部密度定义策略,根据样本所处环境调节其局部密度的大小,准确找到密度峰值;通过共享逆近邻计算相似性,由相似性矩阵分配代表,避免样本分配策略产生的错误连带效应.设置了复杂形态合成数据集、真实数据集和较大规模数据集进行分组实验.实验结果表明,本文算法在复杂形态、真实及较大规模数据集上聚类优势显著,精度与效率较DPC算法及其他基于DPC的改进算法均有较大提升. 展开更多
关键词 密度峰值聚类 圆形网格抽样 近似K近邻 逆近邻 共享逆近邻
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印染反渗透浓水中碳酸钠的资源化回用技术研究
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作者 王锡惠 王海涛 +6 位作者 许以农 陈董根 刘鹏 陈东梅 任其成 李忠华 常娜 《无机盐工业》 北大核心 2026年第1期84-91,共8页
印染反渗透(RO)浓水具有有机物含量高、碱度大、盐分复杂的特征,其主要无机盐组分为硫酸钠(Na_(2)SO_(4))、碳酸钠(Na_(2)CO_(3))及碳酸氢钠(NaHCO_(3))的复合体系。针对现有硫酸钠回收技术成熟但高附加值碳酸钠资源化不足的现状,创新... 印染反渗透(RO)浓水具有有机物含量高、碱度大、盐分复杂的特征,其主要无机盐组分为硫酸钠(Na_(2)SO_(4))、碳酸钠(Na_(2)CO_(3))及碳酸氢钠(NaHCO_(3))的复合体系。针对现有硫酸钠回收技术成熟但高附加值碳酸钠资源化不足的现状,创新采用“超滤(UF)+臭氧高级氧化(AOP)+纳滤(NF)”集成工艺,重点突破复杂体系中碳酸钠的分离与回收。结果表明,“UF+AOP”预处理段对色度与COD的去除率分别达到98.87%和88.91%,有效保障纳滤系统的稳定运行;通过加酸调节pH将CO_(3)^(2-)转化为HCO_(3)^(-)后,NF系统在1.6 MPa的运行压力下对SO_(4)^(2-)的截留率为93.42%,对HCO_(3)^(-)的截留率为16.78%,再通过加碱回调pH将HCO_(3)^(-)转化为CO_(3)^(2-),实现Na_(2)SO_(4)与NaHCO_(3)分离。工艺验证表明,整套系统运行稳定可靠。该研究构建印染RO浓水中有价无机盐的选择性回收新方法,为纺织印染行业实现废水零排放与资源循环利用提供具有工程应用价值的解决方案,兼具显著的环境效益与经济效益。 展开更多
关键词 反渗透浓水 超滤 臭氧高级氧化 纳滤 碳酸钠
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