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Fluorescence Enhancement of Polyamine Derivatives of 1,8-Naphthalimide with Transition Metal Ions
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作者 文国涛 朱满洲 +3 位作者 王卓 孟祥明 胡惠媛 郭庆祥 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第6期506-510,共5页
A series of fluorescent chemosensors 1-3 were synthesized to detect transition metal ions. At the room temperature, fluorescence intensities of these chemosensors in acetonitrile without transition metal ions were fou... A series of fluorescent chemosensors 1-3 were synthesized to detect transition metal ions. At the room temperature, fluorescence intensities of these chemosensors in acetonitrile without transition metal ions were found to be very weak, due to the process of the efficient intramolecular photoinduced electron transfer (PET). However, after addition of the transition metal ions, the chemoscnsor 1-3 exhibits obvious fluorescence enhancement. Moreover, the intensity of the fluorescence emission of chemosensors increases significantly in the presence of Zn^2+ and Cd^2+. The fluorescent chemosensors with different polyamine as receptors show diverse affinity abilities to the transition metal ions and signal the receptor-metal ion interaction by the intensity change of fluorescence emission. 展开更多
关键词 Transition metal ion 1 8-naphthalimide Photoinduced electron transfer Fluorescence enhancement Fluorescent chemosensor
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Fluorescent and thermal properties of siloxane-polyurethanes based on 1,8-naphthalimide 被引量:9
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作者 Yan Ma Qian-Yun Tang +2 位作者 Ji Zhu Li-Hong Wang Cheng Yao 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期680-686,共7页
A series of fluorescent siloxane-polyurethanes(HPMS-PUs) containing an amino-functionalized,1 8-naphthalimide,fluorescent monomer(AABD) as a chain extender were synthesized.The properties of the HPMS-PUs were inve... A series of fluorescent siloxane-polyurethanes(HPMS-PUs) containing an amino-functionalized,1 8-naphthalimide,fluorescent monomer(AABD) as a chain extender were synthesized.The properties of the HPMS-PUs were investigated by UV–vis and fluorescence spectroscopies,thermogravimetric analysis and thermal migration behavior.The maximum absorption and emission wavelengths of HPMS-PUs showed a red shift of about 4 nm and a blue shift of about 9 nm,respectively,compared to those of AABD.The Stokes shifts of AABD and HPMS-PU2 were 3514 and 2931 cm 1,respectively.The quantum yield of HPMS-PU2 was 0.79,which was six times higher than that of AABD.Concentration self-quenching was observed in both AABD and HPMS-PUs.The fluorescence of HPMS-PUs was quite stable with respect to both temperature and fluorescence quencher effects.The thermal stability of HPMS-PUs increased with AABD content.The fluorophore units in the HPMS-PUs did not readily migrate. 展开更多
关键词 Polysiloxane Polyurethane 1 8-naphthalimide Fluorescence Thermal properties
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New trends of molecular probes based on the fluorophore4-amino-1,8-naphthalimide 被引量:1
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作者 Lin Zhou Lijuan Xie +1 位作者 Chuanhao Liu Yi Xiao 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第10期1799-1808,共10页
4-Amino-1,8-naphthalimide(ANI) represents a valuable fluorophore from which a large number of probes have been derived in order to meet the requirements from the fields of biological sensing and imaging. In this revie... 4-Amino-1,8-naphthalimide(ANI) represents a valuable fluorophore from which a large number of probes have been derived in order to meet the requirements from the fields of biological sensing and imaging. In this review, the major progresses of ANI-based fluorescent probes in the past decade have been highlighted and categorized into three trends. The future development of ANI probes is also expected. This review provides a great deal of references and illuminating comments which will be helpful for the researchers designing and using fluorescent probes. 展开更多
关键词 4-Amino-1 8-naphthalimide TWO-PHOTON SUBCELLULAR ORGANELLE ENZYME Hybrid
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Theoretical Study on the Electronic Structures and Spectral Properties of 1,8-Naphthalimide Derivatives
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作者 王艳 高慧 +2 位作者 杨平 聂光华 宋新建 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期813-820,共8页
The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-... The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-(2-tert-butylphenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide(2), and 4-[2,4-di(tert-butyl)]phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(3), are investigated by density functional theory(DFT) and time-dependent density functional theory(TD-DFT) calculations in conjunction with polarizable continuum models(PCMs). Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311+G(d,p) method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311+G(d,p) level. We find that the gap between the highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results. 展开更多
关键词 1 8-naphthalimide derivatives density functional theory frontier molecular orbital absorption spectrum emission spectrum
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A Novel Naked-Eye and Dual-Channel Responsive Fluorescent Probe for Cu2+ Based on 3,4-Disubstituted-1,8-naphthalimide
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作者 李辉 郝志云 +1 位作者 盂欣 朱以常 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期235-239,I0002,共6页
A new 3,4-disubstituted-l,8-naphthalimide derivative H1 was designed and synthesized as a selective fluorescent probe for Cu2+ over miscellaneous metM ions in aqueous media. Upon mixing with Cup-+ in CH3OH:H2O (1... A new 3,4-disubstituted-l,8-naphthalimide derivative H1 was designed and synthesized as a selective fluorescent probe for Cu2+ over miscellaneous metM ions in aqueous media. Upon mixing with Cup-+ in CH3OH:H2O (1:1, volume ratio), the increase of fluorescence intensity and a bathochromic shift of absorbance of H1 could be observed with a notable color response (changing from yellow to pink), htrthermore, Cu2+ coordinates to the probe H1 and a 1:1 metal-ligand complex was formed. 展开更多
关键词 1 8-naphthalimide Copper(II) FLUORESCENCE
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The remarkable effect of amino hydrogen on membrane permeability and organelle staining of 1,8-naphthalimide dyes
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作者 Zhifeng Li Qinglong Qiao +6 位作者 Ning Xu Kai An Wenchao Jiang Yi Tao Pengjun Bao Yinchan Zhang Zhaochao Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第2期347-351,共5页
Membrane permeability and intracellular diffusion of fluorescent probes determine staining selectivity of intracellular substructures.However,the relationship between the molecular structure of fluorescent probes and ... Membrane permeability and intracellular diffusion of fluorescent probes determine staining selectivity of intracellular substructures.However,the relationship between the molecular structure of fluorescent probes and their membrane permeability and intracellular distribution is poorly understood.In this paper,we reported a series of 1,8-naphthalimide dyes and carried out cell imaging experiments,and found that the presence of amino hydrogen in these dyes played a crucial role in their cell membrane permeability and intracellular distribution.The secondary amino group containing compounds 1-4 show excellent membrane permeability and strong fluorescence in living cells.While the tertiary amine containing dyes 5 and 6 can hardly permeate the cell membrane though they show extremely similar structure with compounds 2-4.Compound 1 can selectively image lipid droplets by selecting the wavelength of excitation light.With the specificity for lysosomes,2 and 4 have been used in long-term time-lapses imaging of lysosomal dynamics and tracking the process of lysosome-lysosome interaction,fusion and movement.The effect of hydrogen-containing amino substituent on the cell membrane permeability of fluorescent molecules is promising for the development of better biocompatible probes. 展开更多
关键词 Amino hydrogen 1 8-naphthalimide Cell permeability Lipid droplet LYSOSOME
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Design of a 1,8-naphthalimide-based OFF-ON type bioorthogonal reagent for fluorescent imaging in live cells
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作者 Zhuzhou Shao Chun Zhang +6 位作者 Xiaohua Zhu Yajun Wang Wenyuan Xu Yu Chen Xiaoming Wang Hailiang Zhu Yong Liang 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第12期2169-2172,共4页
A novel 1,8-naphthalimide-based OFF-ON type fluorogenic sydnone(Naph-Syd) is designed as bioorthogonal probe for imaging.Sydnone moiety efficiently quenches the native fluorescence of 1,8-naphthalimide,which can be re... A novel 1,8-naphthalimide-based OFF-ON type fluorogenic sydnone(Naph-Syd) is designed as bioorthogonal probe for imaging.Sydnone moiety efficiently quenches the native fluorescence of 1,8-naphthalimide,which can be restored with the enhancement of about 300-fold,after reacting with strained cyclooctynes to form pyrazole products(Naph-Pyr).The second-order rate constant of this bioorthogonal cycloaddition can be up to 2.5 L mol^-1s^-1,which benefits imaging of biomolecules at low concentrations in cellular environment. 展开更多
关键词 Bioorthogonal cycloaddition 1 8-naphthalimide Photophysical property Sydnone Turn-on fluorescence
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Synthesis,Crystal Structure and Fluorescence Property of N-n-butyl-4-[di(bromoethyl)]amino-1,8-naphthalimide
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作者 叶非 王志强 +2 位作者 李萍 李关羽 付颖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第5期738-744,共7页
The halogen as a kind of alkylating reagent is used to introduce new group to realize the fluorescence sensors efficient of metal ion detection. The substituent at C-4 position was double bromine, which defined that t... The halogen as a kind of alkylating reagent is used to introduce new group to realize the fluorescence sensors efficient of metal ion detection. The substituent at C-4 position was double bromine, which defined that the halogen as an alkylating reagent should be further researched and detected for Hg2+. Therefore, the N-n-butyl-4-[di(bromoethyl)]amino-1,8-naphthalimide has been synthesized to detect some metal ions. The title compound has been prepared via substitute reaction and was characterized by IR, 1H NMR, 13 C NMR, and MS. It crystallizes in triclinic, space group P1 with a = 9.0071(18), b = 9.804(2), c = 13.073(3)A, α = 73.17(3), β = 71.73(3), γ = 62.95(3)°, Z = 2, V = 961.5(3) A3, Dc = 1.666 g/cm3, F(000) = 484, μ(Mo Kα) = 4.232 mm-1, R = 0.0429 and w R = 0.1004. The presence of intermolecular hydrogen bonds as well as π-π stacking interaction led to the stability of the compound. The fluorescence intensity was obviously lower than that of other ions when Hg2+ was added with the concentration of 1 × 10^-5 mol·L-1. 展开更多
关键词 N-n-butyl-4-[di(bromoethyl)]amino-1 8-naphthalimide SYNTHESIS single crystal fluorescence
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Comparative Studies on Two 1,8-Naphthalimide Derivatives with Experimental and Theoretical Methods 被引量:1
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作者 赵朴素 景龙 +3 位作者 李玉峰 朱园 王静 建芳芳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期676-686,共11页
Two 1,8-naphthalimide derivatives of 7H-benzimidazo[2,1,-a]benz[de] isoquino- lin-7-one(1) and 4-bromo-7H-benzimidazo[2,1,-a]benz[de]isoquinolin-7-one(2) have been synthesized and characterized by elemental analys... Two 1,8-naphthalimide derivatives of 7H-benzimidazo[2,1,-a]benz[de] isoquino- lin-7-one(1) and 4-bromo-7H-benzimidazo[2,1,-a]benz[de]isoquinolin-7-one(2) have been synthesized and characterized by elemental analysis, IR, 1H NMR, UV-Vis and fluorescence spectra. For the two compounds, density functional theory(DFT) calculations of the structures and natural population atomic charge analysis have been performed at the B3LYP/6-311G** level of theory. Based on Onsager reaction filed model and by using TD-DFT method at the B3LYP/6-311G** level, electron spectra of 1 and 2 with solvent effect in CHCl3 solvent have been predicted, which are in agreement with the experimental ones. Comparative studies on 1 and 2 indicate that introducing an electron-withdrawing group of Br into the 4-position of naphthalene ring in 2 does not significantly make the molecular geometry of 2 different from that of 1, but evidently changes the atomic charge redistribution, moves the positive-negative charges center and then changes the dipole moment in 2. Additionally, for compound 2, the existence of Br atom has also influenced the peak intensity and peak locations in both electron and fluorescence spectra. 展开更多
关键词 1 8-naphthalimids DFT calculation atomic charge distribution electronic spectra fluorescence spectra
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Selective and Sensitive Fluorescent Chemosensors for Cu2+ Ion Based upon Bis-1,8-naphthalimide Dyads 被引量:1
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作者 Dai,Huiling Xu,Hui 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第2期267-272,共6页
A series of new fluorescent chemosensors 5a--5e, composed of two aminonaphthalimide fluorophores and 2,6-bis((N-aminoalkyl)aminocarboxy)pyridines, were prepared, characterized, and their fluorescent properties to-... A series of new fluorescent chemosensors 5a--5e, composed of two aminonaphthalimide fluorophores and 2,6-bis((N-aminoalkyl)aminocarboxy)pyridines, were prepared, characterized, and their fluorescent properties to- wards heavy and transition metal (HTM) ions were investigated. Chemosensors 5e--Se exhibited high selectivity and sensitivity for Cu2+ ion over other HTM ions with fluorescent quenching (green to colourless). It clearly demonstrated that the length of the linkers (diamines) between the aminonaphthalimides and 2,6-dicarboxypyridine of 5a--Se was very important for their sensitivity and selectivity for Cu2~ ion over other HTM ions. 展开更多
关键词 fluorescence sensors 1 8-naphthalimide metal ion SELECTIVITY
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A New Fluorescent Chemosensor for Metal Ions Based upon 1,8-Naphthalimide and 8-Hydroxyquinoline
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作者 徐晖 曾习文 代会苓 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第10期2165-2168,共4页
A new fluorescent chemosensor based upon 1,8-naphthalimide and 8-hydroxyquinoline was synthesized, and its fluorescent properties in the presence of different metal cations (Hg^2+, Ag^+, Zn^2+, Fe^2+, Cd^2+, Pb^... A new fluorescent chemosensor based upon 1,8-naphthalimide and 8-hydroxyquinoline was synthesized, and its fluorescent properties in the presence of different metal cations (Hg^2+, Ag^+, Zn^2+, Fe^2+, Cd^2+, Pb^2+, Ca^2+, Cu^2+, Mg^2+, and Ba^2+) were investigated. It displayed fluorescence quenching with some heavy and transition metal (HTM) ions, and the quenching strongly depended on the nature of HTM ions. 展开更多
关键词 FLUORESCENCE SENSORS 1 8-naphthalimide 8-HYDROXYQUINOLINE metal ion
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基于Ru(dpp)_(3)Cl_(2)@ZIF-8-PDMS的光氧传感膜构建及其细胞氧微环境监测
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作者 郭婷 林海锋 +1 位作者 李红花 林玲 《分析测试学报》 北大核心 2026年第1期12-20,共9页
针对现有氧检测技术普遍存在的灵敏度不足与响应迟缓问题,该研究通过溶剂热法成功制备Ru(dpp)_(3)Cl_(2)(三(4,7-二苯基-1,10-菲咯啉)二氯化钌(Ⅱ))@ZIF-8(沸石咪唑酯骨架-8)复合纳米颗粒,并将其均匀分散于聚二甲基硅氧烷(PDMS)基体内,... 针对现有氧检测技术普遍存在的灵敏度不足与响应迟缓问题,该研究通过溶剂热法成功制备Ru(dpp)_(3)Cl_(2)(三(4,7-二苯基-1,10-菲咯啉)二氯化钌(Ⅱ))@ZIF-8(沸石咪唑酯骨架-8)复合纳米颗粒,并将其均匀分散于聚二甲基硅氧烷(PDMS)基体内,构建出新型Ru(dpp)_(3)Cl_(2)@ZIF-8-PDMS复合光氧传感膜。得益于ZIF-8的限域效应及多孔结构特性,所开发传感膜的探针荧光漂白率降低42%,氧响应灵敏度较纯PDMS膜提升2.3倍。经优化后,该传感系统成功实现了对HeLa细胞培养体系溶解氧梯度的动态实时监测,为生命科学领域的氧微环境研究提供了新型检测工具。 展开更多
关键词 氧传感器 荧光猝灭 细胞代谢 ZIF-8
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血清IL-8、LPS表达水平与重症急性胰腺炎患者短期预后的关系
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作者 成赋斌 吴文进 《中外医学研究》 2026年第1期25-28,共4页
目的:探讨血清白细胞介素-8(IL-8)、内毒素(LPS)表达水平与重症急性胰腺炎(SAP)患者短期预后的关系,为临床早期评估患者病情及预后提供新的参考指标。方法:选取2022年1月—2025年1月于武警广东总队医院就诊的120例SAP患者为研究对象,根... 目的:探讨血清白细胞介素-8(IL-8)、内毒素(LPS)表达水平与重症急性胰腺炎(SAP)患者短期预后的关系,为临床早期评估患者病情及预后提供新的参考指标。方法:选取2022年1月—2025年1月于武警广东总队医院就诊的120例SAP患者为研究对象,根据患者短期预后情况分为预后良好组(n=98)和预后不良组(n=22),检测两组血清IL-8、LPS表达水平,分析其与患者短期预后的相关性。结果:预后不良组血清IL-8、LPS表达水平均高于预后良好组,差异有统计学意义(P<0.05)。血清IL-8、LPS表达水平均为SAP患者短期预后的独立危险因素,ROC曲线分析显示其对患者短期预后具有一定的预测价值。结论:血清IL-8、LPS表达水平与SAP患者短期预后密切相关,联合检测可为早期评估患者预后提供重要依据,为制定个性化治疗方案提供参考。 展开更多
关键词 重症急性胰腺炎 白细胞介素-8 血清 内毒素 炎症因子
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Bifunctional fluorescent probes for hydrogen peroxide and diols based on a 1,8-naphthalimide fluorophore
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作者 SUN Wei MA Zhao +3 位作者 LI Jing LI WenHua DU LuPei LI MinYong 《Science China Chemistry》 SCIE EI CAS 2013年第10期1440-1445,共6页
This report discloses a series of naphthalimide-based bifunctional fluorescent probes for hydrogen peroxide and diols.As a result,these molecules not only demonstrated high turn-on fluorescent response and good select... This report discloses a series of naphthalimide-based bifunctional fluorescent probes for hydrogen peroxide and diols.As a result,these molecules not only demonstrated high turn-on fluorescent response and good selectivity towards hydrogen peroxide over other relevant reactive oxygen species,but also displayed different responses to diols.Therefore,these fluorescent probes could be served as sensitive,selective and practical chemosensors for both hydrogen peroxide and diols under physiologicallike conditions. 展开更多
关键词 1 8-naphthalimide bifunctional fluorescent probe hydrogen peroxide DIOLS
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基于YOLOv8-MI软枣猕猴桃小目标果实识别和定位方法
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作者 葛宜元 李奥 +3 位作者 孟庆祥 刘德江 梁秋艳 马浏轩 《农机化研究》 北大核心 2026年第4期249-257,共9页
软枣猕猴桃营养价值丰富,但由于果实小、分布密集且易受逆光影响等问题导致在自动化采摘过程中果实识别和定位精度低,严重影响采摘效率。为此,提出了一种基于YOLOv8网络结构的YOLOv8-MI软枣猕猴桃目标检测方法。对YOLOv8进行优化,主干... 软枣猕猴桃营养价值丰富,但由于果实小、分布密集且易受逆光影响等问题导致在自动化采摘过程中果实识别和定位精度低,严重影响采摘效率。为此,提出了一种基于YOLOv8网络结构的YOLOv8-MI软枣猕猴桃目标检测方法。对YOLOv8进行优化,主干网络中引入CBIM增强型空间金字塔池化模块,提升对软枣猕猴桃果实关键特征的提取能力;在颈部网络中使用Bi-FPN模块并增加小目标检测层,增强多尺度特征融合效果和小目标检测精度;在头部网络中引入MPDIoU-I损失函数动态调整学习速率,用以捕捉小目标的特征,提升果实在密集遮挡和逆光情况下的识别精度。优化结果表明:YOLOv8-MI的精确率、召回率、平均精度分别提高了8.60、7.50、6.86个百分点,模型权重仅增加了1.65 MB。在密集遮挡和逆光情况下,模型的精确率、召回率、平均精度分别提高了10.20、8.70、7.72个百分点。基于YOLOv8-MI的识别结果,运用SGBM-CL定位算法得出采摘点坐标,与人工标定数据对比,X、Y、Z方向的定位误差分别为9.09、5.98、6.10 mm,可以满足采摘精度需求。进一步对果实进行识别定位验证,系统总体识别成功率达88%,准确定位率达82%,具有较强的实用性与可靠性。 展开更多
关键词 软枣猕猴桃 小目标果实 识别定位 逆光补偿 密集遮挡 YOLOv8-MI
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基于改进YOLOv8小麦田间杂草检测方法研究
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作者 石琳 郭攀 刘志兵 《中国农机化学报》 北大核心 2026年第1期128-132,共5页
为实现智能化小麦田间杂草管理,提出一种基于改进YOLOv8小麦田间杂草检测方法。建立小麦田间杂草数据集进行模型训练、验证和测试,将C2f与全维动态卷积(ODConv)融合形成C2f—ODConv结构,以增强模型对杂草特征的提取能力;在检测头部分加... 为实现智能化小麦田间杂草管理,提出一种基于改进YOLOv8小麦田间杂草检测方法。建立小麦田间杂草数据集进行模型训练、验证和测试,将C2f与全维动态卷积(ODConv)融合形成C2f—ODConv结构,以增强模型对杂草特征的提取能力;在检测头部分加入3组SimAM注意力模块,提升模型对杂草特征的关注度;采用Inner—IoU损失函数优化模型的回归性能。结果表明,改进模型的精确率为77.48%,召回率为66.45%,平均精度均值为72.37%,相比于原YOLOv8模型分别提升3.66%、4.08%、3.15%,能够满足实际应用中对杂草检测精确度的要求。为小麦田间杂草智能检测提供技术支持,为精准农业和可持续杂草管理提供新思路。 展开更多
关键词 小麦 田间杂草 智能化除草 YOLOv8
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Studies on the Transition Metal Ion Induced Fluorescence Enhancement of 1,8-Naphthalimide Derivatives
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作者 文国涛 朱满洲 +3 位作者 王卓 孟祥明 胡惠媛 郭庆祥 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2006年第9期1230-1237,共8页
Two fluorosensor systems have been designed and synthesized with their photophysical properties and fluorescence responses toward the transition metal ions studied. The fluorosensor was composed of 1,8-naphthalimide a... Two fluorosensor systems have been designed and synthesized with their photophysical properties and fluorescence responses toward the transition metal ions studied. The fluorosensor was composed of 1,8-naphthalimide and 4-chloro-1,8-naphthalimide as fluorophore respectively, an amino moiety as the receptor and a hydrocarbon chain as the spacer to link the fluorophore and receptor. Fluorescence intensity of these systems is very weak due to the process of the efficient intramolecular photoinduced electron transfer (PET) in the absence of metal ions. Titration of the transition metal ions can switch on the fluorescence immediately. The intensity of released fluorescence is even higher than the expected from the consideration of the PET in these systems. It may be rationalized that the receptor bound to transition metal ions and the solvation of the fluorophore by the water molecules from the hydrated transition metal salts, may significantly cause fluorescence enhancement. 展开更多
关键词 1 8-naphthalimide photoinduced electron transfer fluorescence enhancement fluorescent sensor
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基于改进YOLOv8的遥感影像变电站目标识别
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作者 刘润杰 许慧娜 +2 位作者 胡宇 王一 谢国钧 《郑州大学学报(工学版)》 北大核心 2026年第1期33-40,共8页
针对现有研究多集中于变电站局部结构检测而缺乏大区域快速发现与动态监测的问题,通过高分辨率卫星影像实现变电站的高效识别,提升电网安全隐患排查能力。首先构建了基于高分辨率光学卫星影像的变电站目标检测样本库;随后提出改进的YOL... 针对现有研究多集中于变电站局部结构检测而缺乏大区域快速发现与动态监测的问题,通过高分辨率卫星影像实现变电站的高效识别,提升电网安全隐患排查能力。首先构建了基于高分辨率光学卫星影像的变电站目标检测样本库;随后提出改进的YOLOv8算法,在骨干网络中嵌入SimAM轻量级注意力模块以增强细部特征聚焦能力,并将颈部结构替换为Efficient-RepGFPN,结合DySample动态上采样模块设计新型颈部结构GDFPN,以解决多层级特征语义错位问题。实验结果表明:改进方法优于主流检测算法,mAP 75和mAP 50-95分别提升至96.8%和87.1%,验证了其在变电站检测任务中的优越性。所提出的改进YOLOv8方法可有效支持大区域变电站的快速发现与动态监测,为电网安全管理提供了可靠的技术支撑。 展开更多
关键词 YOLOv8 遥感影像 目标检测 变电站 注意力机制
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基于改进YOLOv8的森林火灾检测方法研究
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作者 雷建云 田祚汉 +1 位作者 夏梦 雷瑞璠 《中南民族大学学报(自然科学版)》 2026年第1期97-105,共9页
针对森林火灾检测对实时性要求较高的问题,提出了一种基于改进YOLOv8的森林火灾检测方法 .在YOLOv8的基础上,采用轻量化特征提取网络EfficientNet优化YOLOv8原主干网络CSPDarknet53,以减少计算量并提高模型的收敛速度,进而提高火灾检测... 针对森林火灾检测对实时性要求较高的问题,提出了一种基于改进YOLOv8的森林火灾检测方法 .在YOLOv8的基础上,采用轻量化特征提取网络EfficientNet优化YOLOv8原主干网络CSPDarknet53,以减少计算量并提高模型的收敛速度,进而提高火灾检测速度.此外,融入了SENet注意力机制模块,以增强网络对火灾检测的准确性.使用α-IoU损失函数代替YOLOv8原始损失函数中的CIoU损失函数来计算定位损失,该函数能够自适应地调整IoU的阈值,更好地处理不同大小和形状的目标,同时提高模型对小目标的检测性能.结果表明:该方法的平均准确率(mA@0.5P)达到了87.2%,帧率(FPS)提升了17帧,显著提高了火灾检测的实时性. 展开更多
关键词 深度学习 YOLOv8模型 森林火灾检测 实时性
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血清分形趋化因子、S100钙结合蛋白A8与老年重症肺炎合并呼吸衰竭患者预后的关系
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作者 王莉 沈德栋 《中国临床医生杂志》 2026年第1期40-43,共4页
目的探讨血清分形趋化因子(FKN)、S100钙结合蛋白A8(S100A8)与老年重症肺炎(SP)合并呼吸衰竭患者预后的相关性。方法前瞻性选取2022年6月至2024年6月在中国医科大学附属盛京医院进行治疗的老年SP合并呼吸衰竭患者104例为研究对象,根据... 目的探讨血清分形趋化因子(FKN)、S100钙结合蛋白A8(S100A8)与老年重症肺炎(SP)合并呼吸衰竭患者预后的相关性。方法前瞻性选取2022年6月至2024年6月在中国医科大学附属盛京医院进行治疗的老年SP合并呼吸衰竭患者104例为研究对象,根据预后分为存活组(n=81)和死亡组(n=23)。酶联免疫吸附试验检测患者血清FKN、S100A8水平;利用Cox回归模型评估患者预后的影响因素;构建受试者操作特征(ROC)曲线评估预测患者预后准确性。结果死亡组急性生理学和慢性健康状况评价Ⅱ评分、血清C反应蛋白、降钙素原及血清FKN、S100A8水平均高于存活组(P<0.05),上述指标升高均是影响患者死亡的危险因素(P<0.05)。血清FKN、S100A8联合预测患者预后的曲线下面积优于二者单独检测(Z_(联合-FKN)=2.767,Z_(联合-S100A)=2.029,P<0.05)。结论老年SP合并呼吸衰竭患者血清FKN、S100A8表达水平上升,二者联合预测在患者预后方面具有更高的价值。 展开更多
关键词 重症肺炎 呼吸衰竭 分形趋化因子 S100钙结合蛋白A8 预后
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