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Csp^(2)-H functionalization as an efficient catalytic route to carbazoles
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作者 Giulia Brufani Edoardo Bazzica +2 位作者 Yanlong Gu Francesco Mauriello Luigi Vaccaro 《Chinese Chemical Letters》 2026年第1期39-56,共18页
Given the broad applicability of carbazole structural moieties in materials science and medicinal chemistry,significant efforts have been devoted to developing efficient synthetic catalytic methodologies to access thi... Given the broad applicability of carbazole structural moieties in materials science and medicinal chemistry,significant efforts have been devoted to developing efficient synthetic catalytic methodologies to access this valuable scaffold.Catalyzed direct Csp^(2)-H functionalization provides an effective and costefficient approach to synthesizing carbazoles from simple and readily available starting materials,ensuring a promising path characterized by excellent atom and step economy.This review highlights the substantial progress made in the last 10 years in advancing catalytic Csp^(2)-H functionalization techniques for synthesizing carbazoles. 展开更多
关键词 C-H functionalization CARBAZOLES Synthetic methodologies CATALYSIS
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Self-Activating Integrated Carbon-Based Air Cathodes With In Situ Oxygen Functionalization for Durable and High-Performance Metal-Air Batteries
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作者 Funing Bian Yuexi Chen +3 位作者 Hongfei Zhang Junfang Cheng Shulin Gao Sujuan Hu 《Carbon Energy》 2026年第1期176-186,共11页
Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal ... Carbon-based air cathodes offer low cost,high electrical conductivity,and structural tunability.However,they suffer from limited catalytic activity and inefficient gas transport,and they typically rely on noble metal additives or complex multilayer configurations.To tackle these issues,this study devised a self-activated integrated carbon-based air cathode.By integrating in situ catalytic site construction with structural optimization,the strategy not only induces the formation of oxygen functional groups(─C─OH,─C═O,─COOH),hierarchical pores,and uniformly distributed active sites,but also establishes a favorable electronic and mass-transport environment.Furthermore,the roll-pressing-based integrated design streamlines electrode construction,reinforces interfacial bonding,and significantly enhances mechanical stability.Density functional theory(DFT)calculations show that oxygen functional groups initiate hydrogen bonding interaction and promote charge enrichment,which improves the activity of the cathode and facilitates intermediate adsorption/desorption in oxygen reduction and evolution reactions processes.As a result,the integrated air cathode-based rechargeable zinc-air batteries(RZABs)achieve a high specific capacity of 811 mAh g^(-1).It also performs well in quasi-solid-state RZABs and silicon-air batteries systems across a wide temperature range,demonstrating strong adaptability and application potential.This study provides a scalable and cost-effective design strategy for high-performance carbon-based air cathodes,offering new insights into advancing durable and practical metal-air energy systems. 展开更多
关键词 integrated air cathode metal-air batteries ORR/OER oxygen functional group engineering SELF-ACTIVATION
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Recent Advances toward Electro- and Electrophotochemical 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)-Catalyzed C—H/C—F Bonds Functionalization 被引量:1
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作者 Yongmei Li Liangbo Sun +1 位作者 Kun Xu Chengchu Zeng 《有机化学》 北大核心 2025年第2期668-676,共9页
2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) is a stoichiometric oxidant that is frequently used in traditional organic synthesis. Recently, the rapid development of organic electrochemistry has led to new advancem... 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) is a stoichiometric oxidant that is frequently used in traditional organic synthesis. Recently, the rapid development of organic electrochemistry has led to new advancements in DDQ-catalyzed C—H bonds functionalization. Moreover, the challenging C—H functionalization of electron-deficient arenes has been achieved through the merger of electrochemical DDQ catalysis and photoirradiation. In addition, the synthetic utility of electrophotochemical DDQ catalysis was further demonstrated by the nucleophilic aromatic substitution (SNAr) reaction of unactivated aryl fluorides. The recent developments in electro- and electrophotochemical DDQ-catalyzed C—H/C—F func- tionalizations with attention to their strategies and mechanistic insights are summarized. It is hoped that this not only deepens the understanding of this field, but also helps relevant researchers expand the application scope of DDQ catalysis. 展开更多
关键词 2 3-dichloro-5 6-dicyano-1 4-benzoquinone(DDQ) electrocatalysis organic electrosynthesis electrophotocatalysis C-H functionalization C-F functionalization
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Visible-Light-Mediated O-H Functionalization Reactions of Alkenyl Alcohols with Diazo Compounds
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作者 Xie Haochi Qin Yongkang +6 位作者 Yang Ting Li Hujin Sun Jiajia Qian Mingcheng Zhao Shuai Hou Ya'nan Chen Xin 《有机化学》 北大核心 2025年第8期3004-3016,共13页
Visible-light-mediated O-H functionalization reactions of alcohols with diazo compounds have been fully developed in recent years.However,alkenyl and acetylenic alcohols were rarely examined in these reactions due to ... Visible-light-mediated O-H functionalization reactions of alcohols with diazo compounds have been fully developed in recent years.However,alkenyl and acetylenic alcohols were rarely examined in these reactions due to the inevitable side reactions involving cycloaddition.Herein,the visible-light-mediated O-H functionalization reactions of alkenyl alcohols with diazo compounds were developed.This process competed favorably with the cycloaddition reaction.A series of multifunctional ethers were provided in low to high yields with aryldiazoacetates or 3-diazooxindoles.Biologically relevant spirooxindole-fused oxacycle could be easily accessed from the O-H functionalization product of alkenyl alcohol and 3-diazooxindole. 展开更多
关键词 VISIBLE-LIGHT O-H functionalization alkenyl alcohol diazo compound spirooxindole-fused oxacycle
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Transition Metal-Catalyzed Asymmetric Migratory Allylic C—H Functionalization of Remote Dienes
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作者 Jingming Zhang Zhitao He 《有机化学》 北大核心 2025年第2期592-601,共10页
Asymmetric allylic C—H functionalization is a valuable and challenging research area. Different from the conventional direct allylic C—H cleavage strategy, transition metal-catalyzed migratory allylic substitution o... Asymmetric allylic C—H functionalization is a valuable and challenging research area. Different from the conventional direct allylic C—H cleavage strategy, transition metal-catalyzed migratory allylic substitution of remote dienes has emerged as a new route to achieve allylic C—H functionalization enantioselectively. This review provides a detailed summary of the development and advance of this strategy, introduces the related mechanistic processes, and discusses the area based on the types of catalysts and products. 展开更多
关键词 remote dienes metal walking migratory allylic substitution allylic C-H bond functionalization asymmetric synthesis
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Application of Functional Group Migration Strategies in Photodriven Difunctionalization of Unsaturated Hydrocarbons
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作者 He Chonglong Zhou Youkang +1 位作者 Duan Xinhua Liu Le 《有机化学》 北大核心 2025年第5期1478-1508,共31页
Difunctionalization of unsaturated hydrocarbons is a pivotal synthetic strategy enabling the conversion of alkenes and alkynes into high value-added compounds.It allows for the introduction of two functional groups in... Difunctionalization of unsaturated hydrocarbons is a pivotal synthetic strategy enabling the conversion of alkenes and alkynes into high value-added compounds.It allows for the introduction of two functional groups into the unsaturated bond in a single step,facilitating the efficient construction of complex molecular architectures,which has been widely utilized in material chemistry,pharmaceutical and fine chemical synthesis.Recently,significant progress has been made via free radical-mediated difunctionalization due to the extensive application of photocatalysis.However,highly selective difunc-tionalization reactions still remain challenging.The research progress of selective difunctionalization of unsaturated hydro-carbons using a free radical addition/functional group migration strategy over the past decade is summarized,and synthetic strategies and key reaction steps are systematically elaborated. 展开更多
关键词 visible-light-driven unsaturated hydrocarbon functional group migration difunctionalization
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Recent Progress in the Dehydroxylative Functionalizations of Alcohols
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作者 Jiao Yanyan Wang Feige +1 位作者 Xiao Jian An Xiaode 《有机化学》 北大核心 2025年第10期3587-3612,共26页
As naturally abundant and readily available starting materials,alcohols are frequently employed as synthetic building blocks in organic synthesis.The hydroxyl group,which serves as the characteristic functional group ... As naturally abundant and readily available starting materials,alcohols are frequently employed as synthetic building blocks in organic synthesis.The hydroxyl group,which serves as the characteristic functional group of alcohols,is the primary reactive site for these compounds.Consequently,dehydroxylative functionalization reaction is one of the representative transformations of alcohols and has demonstrated significant potential in constructing new chemical bonds.Over the past decade,this research field has received continuous and extensive attention.This review comprehensively summarizes the recent advances in the dehydroxylative functionalization of alcohols,discussing on the reaction methodologies and mechanisms for constructing carbon-heteroatom and carbon-carbon bonds from alcohols. 展开更多
关键词 ALCOHOLS dehydroxylative functionalizations dehydroxylative coupling
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Nicotinic Acid Activated Cp_(2)TiCl_(2) for Synergistic Catalysis of C-H Functionalization to Synthesize 2-(N-substituted amino)-1,4-Naphthoquinones
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作者 WANG Yunyun MA Caixia WANG Tao 《分子催化(中英文)》 北大核心 2025年第5期472-482,I0005,共12页
Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strateg... Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strategy for the functionalization and conversion of C-H bonds of 1,4-naphthoquinones into C-N bonds,providing an effective route to synthesize 2-(N-substituted amino)-1,4-naphthoquinone with high yield under mild conditions.Additionally,the synergistic catalytic mechanism was investigated by 1H NMR titration experiments and LC-MS analysis,with experimental results sufficiently and consistently supporting the proposed mechanism of the catalytic cycle. 展开更多
关键词 C-H functionalization 2-(N-substituted amino)-1 4-naphthoquinone Cp_(2)TiCl_(2) synergistic catalysis
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Recent Advancements in Biochar Functionalization from Crop Residues for a Green Future
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作者 Omojola Awogbemi Daramy Vandi Von Kallon Ramesh CRay 《Journal of Renewable Materials》 2025年第11期2191-2233,共43页
Increased human and industrial activities have exacerbated the release of toxic materials and acute envi-ronmental pollution in recent times.Biochar,a carbon-rich material produced from biomass,is gaining momentum as ... Increased human and industrial activities have exacerbated the release of toxic materials and acute envi-ronmental pollution in recent times.Biochar,a carbon-rich material produced from biomass,is gaining momentum as a versatile material for attaining a sustainable environment.The study reviews the application of functionalized biochar for energy storage,environmental remediation,catalysis,and sustainable agriculture,aiming to achieve a greener future.Thedeployment of crop residues as a renewable feedstock for biochar,and their properties,compositions,modification,and functionalization techniques are also discussed.Additionally,the avenues for applying functionalized biochar to achieve a greener future,future trends and innovations,challenges,and future research directions are highlighted.Despite the limitations of scalability,ecotoxicological risks,logistical issues,lack of characterization protocols,high production costs,poor social acceptance,and inadequate policy and regulatory frameworks,functionalized biochar offers a better surface area,improved porosity,enhanced functional groups,and higher recoverability,leading to improved performance,adsorption capacity,biodegradability,and applications in specialized fields.Future research should prioritize standardization,scalability,cost reduction strategies,expansion of application areas,integration of emerging tools such as artificial intelligence and predictive modeling,and the development of policy and regulatory frameworks,ensuring that biochar’s full potential is harnessed effectively to support a low-carbon,resource-efficient future and global sustainability goals. 展开更多
关键词 functionalization techniques BIOCHAR crop residues adsorption capacity green future energy storage
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Pd/Cu-cocatalyzed multi-site functionalization of in-situ generated alkenes toward carbazole-based aggregation-induced emission luminogens
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作者 Meiqi Zhang Xueyuan Yan +8 位作者 Zheng Liu Hongyuan Bai Hongwei Ma Genping Huang Bo Zhang Dezhu Xu Wenjia Han Li Han Tenglong Guo 《Chinese Journal of Catalysis》 2025年第2期176-184,共9页
In contrast to the predominant mono or difunctionalization of alkenes,the multi-site functionalization of alkenes involving the synergistic formation of more than two new C–C or C–X bonds is much challenging,especia... In contrast to the predominant mono or difunctionalization of alkenes,the multi-site functionalization of alkenes involving the synergistic formation of more than two new C–C or C–X bonds is much challenging,especially for developing new reaction pathway to afford the functional heterocycle compounds with aggregation-induced emission(AIE)property has been rarely reported.In present work,the multi-site functionalization of in situ generated alkenes with indoles has been developed for the synthesis of diversely functionalized carbazoles through the synergistic construction of multiple C–C bonds and C=O bond.A proposed reaction sequence involving C–H alkenylation/radical oxygen atom transfer/Diels-Alder cycloaddition/dehydrogenative aromatization was supported by experiments and density functional theory calculations.Further derivative carbazole-linked-quinoxaline skeletons represent a class of AIEgens with acceptor-donor-acceptor configuration,which generated the desired twisted intramolecular charge transfer(TICT)AIE properties and could be used as fluorescent probes for detecting the micrometer-sized phase separation of polymer blends.The protocol provides a concise route for the synthesis and application of carbazole-based AIE luminogens. 展开更多
关键词 Multi-site functionalization CARBAZOLES Aggregation-induced emission luminogens Radical oxygen atom transfer Microphase separation
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Recent advances in directing group assisted transition metal catalyzed para-selective C-H functionalization
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作者 Wei-Bin Li Xiao-Chao Huang +2 位作者 Pei Liu Jie Kong Guo-Ping Yang 《Chinese Chemical Letters》 2025年第6期68-77,共10页
The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundan... The transition metal-catalyzed C–H activation have been considered as increasingly useful approach for installing new functional groups onto organic small molecules due to their high step-and atom-economy,the abundance of hydrocarbon compounds,and the potential for late-stage functionalization of complex organic molecules.The ortho-and meta-C-H activation and functionalization of aromatic compounds have been widely explored in recent years,however the distal para-C-H activation and functionalization has remained a significant challenge because of the difficulty in forming energetically favorable metallacyclic transition states.The utilization of appropriate directing groups or templates as well as the meticulous design of catalysts and ligands has proven to be effective in transition-metal-catalyzed remote para-C-H bonds activation and functionalization of aromatic compounds.This review aims to summarize the strategies for controlling para-selective C–H functionalization using the directing group,template engineering,and catalyst/ligand design under transition metals catalysis in recent years. 展开更多
关键词 C-H activation Transition metal catalysis SELECTIVITY Remote functionalization Directing group
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Two vicinal C(sp^(3))-F bonds functionalization of perfluoroalkyl halides (PFAHs)
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作者 Jun Jiang Hui Dai Tao Tu 《Chinese Chemical Letters》 2025年第7期4-5,共2页
Organofluorines play a crucial role in medicine,agrochemicals,and materials science.Adding fluorine to molecules creates structures with specific beneficial properties or tunes properties through interactions with the... Organofluorines play a crucial role in medicine,agrochemicals,and materials science.Adding fluorine to molecules creates structures with specific beneficial properties or tunes properties through interactions with their environment.Many popular pharmaceuticals and agrochemicals contain fluorine because it enhances hydrogen bonding at protein’s active sites. 展开更多
关键词 vicinal c sp f bonds materials science organofluorines medicine fluorine functionalization tunes properties agrochemicals enhances hydrogen bonding
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Depolymerization and Functionalization of Super Engineering Plastics
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作者 Boning Gu Rui Huang +1 位作者 Yinsong Zhao Xuefeng Jiang 《Chinese Journal of Polymer Science》 2025年第6期876-886,I0006,共12页
Chemical recycling/upcycling of plastics has emerged as one of the most promising strategies for the plastic circular economy,enabling the depolymerization and functionalization of plastics into valuable monomers and ... Chemical recycling/upcycling of plastics has emerged as one of the most promising strategies for the plastic circular economy,enabling the depolymerization and functionalization of plastics into valuable monomers and chemicals.However,studies on the depolymerization and functionalization of challenging super engineering plastics have remained in early stage and underexplored.In this review,we would like to discuss the representative accomplishments and mechanism insights on chemical protocols achieved in depolymerization of super engineering plastics,especially for poly(phenylene sulfide)(PPS),poly(aryl ether)s including poly(ether ether ketone)(PEEK),polysulfone(PSU),polyphenylsulfone(PPSU)and polyethersulfone(PES).We anticipate that this review will provide an overall perspective on the current status and future trends of this emerging field. 展开更多
关键词 Super engineering plastics Chemical recycling/upcycling DEPOLYMERIZATION functionalization
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Photoelectric synergy induced synchronous functionalization of graphene and its applications in water splitting and desalination
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作者 Limin Wang Feiyi Huang +9 位作者 Xinyi Liang Rajkumar Devasenathipathy Xiaotian Liu Qiulan Huang Zhongyun Yang Dujuan Huang Xinglan Peng Du-Hong Chen Youjun Fan Wei Chen 《Chinese Journal of Structural Chemistry》 2025年第2期25-33,共9页
Chemical functionalization of graphene is a topic of paramount importance to broaden its applications in chemistry,physics,and biological science but remains a great challenge due to its low chemical activity and poor... Chemical functionalization of graphene is a topic of paramount importance to broaden its applications in chemistry,physics,and biological science but remains a great challenge due to its low chemical activity and poor dispersion.Here,we report a strategy for the photosynergetic electrochemical functionalization of graphene(EFG).By using chloride ion(Cl^(-))as the intercalation anions and co-reactants,the electrogenerated radicals confined in the expanded graphite layers enable efficient radical addition reaction,thus grasping crystallineperfect EFG.We found that the ultraviolet irradiation and applied voltage have increased the surface/interface concentration of Cl,thus boosting the functionalization of graphene.Theoretical calculation and experimental results verified the oxygen evolution reaction(OER)on EFG has been improved by regulating the doping of chlorine atoms.In addition,the reduced interlayer distance and enhanced electrostatic repulsion near the basal plane endow the fabricated EFG-based membrane with high salt retention.This work highlights a method for the in situ functionalization of graphene and the subsequent applications in OER and water desalination. 展开更多
关键词 Synchronous functionalization of graphene PHOTOELECTROCHEMISTRY Confined spacing Radical addition reaction Water splitting and desalination
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Stabilized carbon radical-mediated three-component functionalization of amino acid/peptide derivatives
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作者 Shaofeng Gong Zi-Wei Deng +1 位作者 Chao Wu Wei-Min He 《Chinese Chemical Letters》 2025年第5期3-4,共2页
Amino acids are the building blocks of proteins and play vital roles in both biological systems and drug development.In recent years,increasing attention has been given to the functionalization of amino acid derivativ... Amino acids are the building blocks of proteins and play vital roles in both biological systems and drug development.In recent years,increasing attention has been given to the functionalization of amino acid derivatives.Since the introduction of therapeutic insulin in the early 20th century,the conjugation of drug molecules with amino acids and peptides has been pivotal in driving advancements in drug discovery and become an integral part of modern medical practice.Currently,over a hundred peptide-drug conjugates have received global approval and are widely used to treat diseases such as diabetes,cancer,chronic pain,and multiple sclerosis.Key technologies for conjugating peptides with bioactive molecules include antibody-drug conjugates(ADCs),peptide-drug conjugates(PDCs),and proteolysis targeting chimeras(PROTACs).Significant efforts have been dedicated to developing strategies for the modification of amino acids and peptides,with particular focus on site-selective C-H alkylation/arylation reactions.These reactions are crucial for synthesizing bioactive molecules,as they enable the precise introduction of functional groups at specific positions,thereby improving the pharmacological properties of the resulting compounds. 展开更多
关键词 stabilized carbon radical mediated functionalization three component reactions therapeutic insulin drug developmentin drug discovery amino acids conjugation drug molecules biological systems
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Constructive Strategy of Amine Functionalization on Cu−In−Zn−S With N→Cu Coordination for Efficacious Photocatalytic Hydrogen Evolution
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作者 Mengmeng Ma Runkang Lin +4 位作者 Kaige Huang Shizhong Yue Maohong Fan Zhijie Wang Shengchun Qu 《Carbon Energy》 2025年第10期162-173,共12页
Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bon... Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bonds using individual ethylenediamine(EDA)molecules.Our approach witnesses a remarkable photocatalytic hydrogen evolution(PHE)competence of 65.93 mmol g^(−1)h^(−1)driven by visible light,the highest value yielded by CIZS to date.X-ray absorption spectra of CIZS and density functional theory(DFT)calculations confirm the crucial amine N→Cu coordination after amine functionalization.The new emerging coordination via lone-pair electron donation profitably accesses the regulation of the coordination environment,electronic structures,and carrier behavior.Moreover,individual EDA molecule with two-terminal−NH2 group serves as a molecular bridge to hybrid CIZS and NiS_(x)cocatalyst via N→Cu and N→Ni coordination,favorably promoting efficient charge transport.This study provides advances in practical functionalizing photocatalysts. 展开更多
关键词 amine functionalization COORDINATION Cu−In−Zn−S molecular bridges photocatalytic hydrogen evolution
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基于障碍函数的PMSM阻尼可变性能增强滑模控制
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作者 杨荣荣 谭家昌 +3 位作者 张玲 黄华 张朋 王德义 《电机与控制学报》 北大核心 2026年第1期155-166,178,共13页
为了抑制抖振和增强永磁同步电机(PMSM)转速控制性能,提出一种基于障碍函数的永磁同步电机阻尼可变性能增强新型转速滑模控制方法。首先,设计一种非级联转速-电流一体化单环控制架构,该架构直接利用可测量转速和电流直接设计控制器,而... 为了抑制抖振和增强永磁同步电机(PMSM)转速控制性能,提出一种基于障碍函数的永磁同步电机阻尼可变性能增强新型转速滑模控制方法。首先,设计一种非级联转速-电流一体化单环控制架构,该架构直接利用可测量转速和电流直接设计控制器,而无需设计观测器估计角加速度。其次,引入障碍函数使sign切换函数的增益自适应调整,这不但极大削弱抖振,同时还解决电流无法自动受限的问题。此外,在滑模面设计中创新性地设计积分阻尼可变函数,有效地提升转速暂态控制性能。同时积分项使系统动态仅为滑动阶段,大大简化控制器和自适应律的设计复杂度。为了进一步增强鲁棒性,设计一种滤波扰动估计器对PMSM中的匹配和非匹配扰动同时进行估计并补偿。最后,通过实际实验对所提方法进行验证,实验结果表明该控制方法能够有效降低抖振和增强PMSM的转速控制性能。 展开更多
关键词 转速-电流一体化 障碍函数 自动受限 积分阻尼可变函数 滤波扰动估计器
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基于多尺度特征增强的航拍小目标检测算法 被引量:1
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作者 肖剑 何昕泽 +2 位作者 程鸿亮 杨小苑 胡欣 《浙江大学学报(工学版)》 北大核心 2026年第1期19-31,共13页
针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强... 针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强对小目标细粒度特征的捕获;基于PAN-FPN架构调整特征融合网络,增加对浅层特征的关注,同时引入多尺度卷积核增强对目标上下文信息的关注,以适应小目标检测场景;针对传统IoU灵活性、泛化性不强的问题,构建参数可调的Nin-IoU,通过引入可调参数,实现对IoU的针对性调整,以适应不同检测任务的需求;提出轻量化检测头,在增强多尺度特征信息交融的同时减少冗余信息的传递.结果表明,在VisDrone2019数据集上,所提算法以8.08×106的参数量实现了mAP0.5=50.3%的检测精度;相较于基准算法YOLOv8s,参数量降低了27.4%,精度提升了11.5个百分点.在DOTA与DIOR数据集上的实验结果表明,所提算法具有较强的泛化能力. 展开更多
关键词 目标检测 YOLOv8 无人机图像 特征融合 损失函数
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应用单组目标值法评价眼针带针康复对卒中后患者认知功能及运动功能康复效果的研究
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作者 王梅 邵妍 +8 位作者 赵曦彤 刘映洁 陈峣 马逍遥 陈斌 杨森 高晨 韩梅 王鹏琴 《中国针灸》 北大核心 2026年第2期161-167,共7页
目的:采用单组目标值法评价眼针带针康复疗法促进卒中后患者认知功能和运动功能康复的效果。方法:前瞻性连续收集卒中后接受眼针带针康复的患者102例(眼针带针康复组),患者接受基础药物治疗及眼针带针康复,眼针穴取双侧上焦区、下焦区... 目的:采用单组目标值法评价眼针带针康复疗法促进卒中后患者认知功能和运动功能康复的效果。方法:前瞻性连续收集卒中后接受眼针带针康复的患者102例(眼针带针康复组),患者接受基础药物治疗及眼针带针康复,眼针穴取双侧上焦区、下焦区、肝区、肾区,每日1次,治疗5 d后休息2 d,共治疗4周。分别于治疗前后及治疗结束后12周随访评价患者简易精神状态检查量表(MMSE)、蒙特利尔认知评估量表(Mo CA)、Fugl-Meyer评估量表(FMA)和改良Barthel指数(MBI)评分,并与传统针灸(针灸组)和常规康复(常规康复组)治疗效果的目标值进行比较,目标值来源于同类研究证据等级最高的Meta分析。结果:治疗前后各时点,眼针带针康复组患者MMSE、MoCA、FMA、MBI评分均存在时间效应(P<0.001,P<0.01),随时间延长评分分值逐渐升高。目标值法结果显示,在改善认知功能方面,治疗后,眼针带针康复组患者MMSE评分与针灸组目标值比较差异无统计学意义(P>0.05),MoCA评分低于针灸组目标值(P<0.01);随访时,眼针带针康复组患者MMSE评分高于针灸组目标值(P<0.01),Mo CA评分与针灸组目标值比较差异无统计学意义(P>0.05)。在改善运动功能方面,治疗后,眼针带针康复组患者FMA和MBI评分均低于针灸组目标值(P<0.001);随访时,眼针带针康复组患者FMA评分与针灸组目标值比较差异无统计学意义(P>0.05),MBI评分高于针灸组目标值(P<0.05)。治疗后和随访时,除治疗后FMA、MBI评分外,眼针带针康复组患者上述指标均优于常规康复组目标值(P<0.001)。结论:眼针带针康复治疗在改善卒中后认知功能和运动功能方面与传统针灸疗效相当,优于常规康复疗法。 展开更多
关键词 卒中 眼针带针康复 针灸 认知功能 运动功能 单组目标值法
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沙库巴曲缬沙坦治疗Ⅱ型心肾综合征患者的临床疗效及对血管内皮生长因子的影响
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作者 马兰 张志青 《河北医学》 2026年第2期341-347,共7页
目的:探讨沙库巴曲缬沙坦治疗Ⅱ型心肾综合征患者的临床疗效及对血管内皮生长因子的影响。方法:选择2024年4月至2025年2月收治的CRS-2患者144例,依据随机数字表法分为CG组、EG组,各组72例。CG均接受标准治疗,EG在标准治疗基础上加用沙... 目的:探讨沙库巴曲缬沙坦治疗Ⅱ型心肾综合征患者的临床疗效及对血管内皮生长因子的影响。方法:选择2024年4月至2025年2月收治的CRS-2患者144例,依据随机数字表法分为CG组、EG组,各组72例。CG均接受标准治疗,EG在标准治疗基础上加用沙库巴曲缬沙坦治疗。对比两组治疗前后心功能指标、动态心电图心率(AECG)、肾功能指标、血管内皮功能、肱动脉内血流介导的血管舒张功能(FMD)。结果:与CG组比较EG组治疗前后SDNN、SDANN、rMSSD及PNN50差值明显增高(P<0.05);与CG组比较EG组治疗前后LVFS、LVEF及E/A差值明显增高(P<0.05);与CG组比较EG组治疗前后eGFR差值明显增高,与CG组比较EG组治疗前后BUN及Scr差值明显降低(P<0.05);与CG组比较EG组治疗前后EDD功能及D1差值明显增高(P<0.05),但两组患者D0差值比较无明显差异(P>0.05);与CG组比较EG组治疗前后CGRP及NO差值明显增高,与CG组比较EG组治疗前后ET差值明显降低(P<0.05)。结论:沙库巴曲缬沙坦片通过多靶点调控机制,可同步优化CRS-2患者的心肾功能及血管内皮微环境,其疗效确切且安全性良好,为CRS-2的综合治疗提供了新的循证医学依据。 展开更多
关键词 Ⅱ型心肾综合征 沙库巴曲缬沙坦 心功能 肾功能 血管内皮功能
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