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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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Thickness Dependent Behavior of Photoluminescence of Tris(8-hydroxyquinoline)Aluminum Film 被引量:1
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作者 徐以锋 张寒洁 +3 位作者 陈桥 李海洋 鲍世宁 何丕模 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期152-154,共3页
In situ thickness dependent photoluminescence (PL) measurements of tris(8-hydroxyquinoline) aluminum(Alq3) film were performed. At the beginning of Alq3 deposition on the glass substrate, the Alq3 emission showe... In situ thickness dependent photoluminescence (PL) measurements of tris(8-hydroxyquinoline) aluminum(Alq3) film were performed. At the beginning of Alq3 deposition on the glass substrate, the Alq3 emission showed a sharp red-shift. Further deposition of Alq3 resulted slight red-shift, and finally tended to saturated value. The total red-shift of about 12 nm was observed for the Alq3 film thickness range from 2 to 500 nm.This red-shift was attributed to the change from the 2D to 3D exciton state with increasing Alq3 film thickness. Meanwhile, the PL intensity of Alq3 emission increased continuously, and showed a rate change at the initial deposition of Alq3 due to non-rediative decay of excitons arised from the interaction between excitons and the substrate, and finally tended to saturation with the Alq3 thickness. 展开更多
关键词 Tris(8-hydroxyquinoline aluminum film PHOTOLUMINESCENCE RED-SHIFT
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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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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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Studies on synergistic solvent extraction of rare earth elements from nitrate medium by mixtures of 8-hydroxyquinoline with Cyanex 301 or Cyanex 302 被引量:14
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作者 田苗苗 贾琼 廖伍平 《Journal of Rare Earths》 SCIE EI CAS CSCD 2013年第6期604-608,共5页
Synergistic solvent extraction of rare earth elements (REEs) from nitrate medium was investigated with mixtures of 8-hydroxyquinoline (HQ) and acidic organophosphorus extractants, bis(2,4,4-trimethylpentyl) dith... Synergistic solvent extraction of rare earth elements (REEs) from nitrate medium was investigated with mixtures of 8-hydroxyquinoline (HQ) and acidic organophosphorus extractants, bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex 301) and bis(2,4,4-trimethylpentyl) monothiophosphinic acid (Cyanex 302). The extraction behavior of Cyanex 301/Cyanex 302 and their binary mixtures with HQ towards several lanthanoids (La, Nd, Sm, Tb, Ho, Tm) and yttrium (Y) was investigated. The separation ability of REEs was studied according to the various extraction effects. The extraction mechanisms for yttrium were studied with the methods of slope analysis and constant moles in the synergistic systems. The extracted compounds, the equilibrium constants, and thermodynamic functions were also determined. 展开更多
关键词 extraction rare earth elements 8-hydroxyquinoline Cyanex 301 Cyanex 302
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Thermochemical Study on Coordination Complex of Samarium with Salicylic Acid and 8-Hydroxyquinoline 被引量:2
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作者 Wei Deliang Li Qiangguo +5 位作者 Huang Yi Li Xu Ye Lijuan Xiao Shengxiong Yang Dejun Liu Yi 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第2期253-256,共4页
The coordination complex Sm(C_(7)H_(5)O_(2))_(2)·(C_(9)H_(6)NO),synthesized from the reaction of samarium chloride sixhydrate with salicylic acid and 8-hydroxyquinoline,was characterized with IR,elemental analysi... The coordination complex Sm(C_(7)H_(5)O_(2))_(2)·(C_(9)H_(6)NO),synthesized from the reaction of samarium chloride sixhydrate with salicylic acid and 8-hydroxyquinoline,was characterized with IR,elemental analysis,molar conductance,and thermogravimatric analysis.The standard molar enthalpies of solution of[SmCl_(3)·6H_(2)O(s)],[2C_(7)H_(6)O_(3)(s)],[C_(9)H_(7)NO(s)]and[Sm(C_(7)H_(5)O_(3))_(2)·(C_(9)H_(6)NO)(s)]in the calorimetric solvent were determined with the solution-reaction isoperibol calorimeter at 298.15 K to be△sHm^-[SmC_(l3)·6H_(2)O(s),298.15 K]=-103.98±0.04 kJ·mol^(-1),△sHm^-[2 C_(7)H_(6)O_(3)(s),298.15 K]=16.35±0.14 kJ·mol^(-1),△sHm^-[C_(9)H_(7)NO(s),298.15 K]=-6.11±0.08 kJ·mol^(-1)and△sHm^-[Sm(C7H5O3)2·(C9H6NO)(s),298.15 K]=-130.08±0.04 kJ·mol^-1,respectively.The enthalpy was determined to be△rHm^-=89.59±0.18 kJ·mol^-1 for the reaction SmCl3·6H2O(s)+2C7H6O3(s)+C9H7NO(s)=Sm(C7H5O3)2·(C9H6NO)(s)+3HCl(g)+6H2O(l).According to the above results and the data given in literature and through Hess'law,the standard molar enthalpy of formation of Sin(C7H5O3)2·(C9H7NO)(s)was estimated to be△rHm^-[Sm(C7H5O3)2·(C9H6NO)(s),298.15 K]=-2055.9±3.03 kJ·mol^-1. 展开更多
关键词 samarium complex salicylic acid 8-hydroxyquinoline standard molar enthalpies of formation rare earths
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Mitigating phytotoxicity of tetracycline by metal-free 8-hydroxyquinoline functionalized carbon nitride photocatalyst 被引量:1
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作者 Toshali Bhoyar Devthade Vidyasagar Suresh S.Umare 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第3期37-46,共10页
Photooxidative removal of pharmaceuticals and organic dyes is an effective way to eliminate growing micropollutants. However, photooxidation often results in byproducts as secondary hazardous substances such as phytot... Photooxidative removal of pharmaceuticals and organic dyes is an effective way to eliminate growing micropollutants. However, photooxidation often results in byproducts as secondary hazardous substances such as phytotoxins. Herein, we found that photooxidation of common antibiotic tetracycline hydrochloride(TCH) over a metal-free 8-hydroxyquinoline(8-HQ) functionalized carbon nitride(CN) photocatalyst significantly reduces the TCH phytotoxic effect. The phytotoxicity test of photocatalytic treated TCH-solution evaluated towards seed growth of Cicer arietinum plant model endowed natural root and shoot growth.This study highlights the conceptual insights in designing of metal-free photocatalyst for environmental remediation. 展开更多
关键词 Carbon nitride 8-hydroxyquinoline Tetracycline hydrochloride PHOTOCATALYST PHYTOTOXICITY Cicer arietinum
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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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Crystal Structure and Characterization of a Binuclear Cd(Ⅱ) Quaternary Coordination Complex [Cd_2(phen)_2Q_2(BP)]_n(phen=1,10-Phenanthroline,BP = Biphenyl-4,4'-dicarboxylic acid,Q=8-Hydroxyquinoline Anion) 被引量:1
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作者 王家军 崔运成 +3 位作者 高广刚 王仁章 刘博 王小美 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第9期1149-1152,共4页
The structure of a binuclear cadmium(Ⅱ) quaternary complex, [Cd2(phen)2- Q2(BP)]n 1 (phen = 1,10-phenanthroline, BP = biphenyl-4,4′-dicarboxylic acid, Q = 8-hydroxy- quinoline-anion), has been determined by ... The structure of a binuclear cadmium(Ⅱ) quaternary complex, [Cd2(phen)2- Q2(BP)]n 1 (phen = 1,10-phenanthroline, BP = biphenyl-4,4′-dicarboxylic acid, Q = 8-hydroxy- quinoline-anion), has been determined by X-ray crystallography and characterized by elemental analysis, IR spectrum and thermogravimetric analysis. It crystallizes in the monoclinic system, space group P21/n with a = 13.1906(18), b = 10.9623(15), c = 16.947(2)A, β = 111.3430(10)°, V = 2282.5(5)A^3, Z = 4, Mr = 556.85, Dc = 1.620 g/cm^3, F(000) = 1116,μ= 0.994 mm^-1 and S = 1.056. In the structure, 1D chains are connected via biphenyl-4,4′-dicarboxylic acid, 8-hydroxy quinoline anion and binuclear cadmium atoms into an infinite 1-D molecular chain architecture. Via aryl ring π-π stacking interactions a supramolecular structure is formed in 1. 展开更多
关键词 PHEN 8-hydroxyquinoline cadmium(Ⅱ) complex single-crystal structure TG
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Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline 被引量:1
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作者 张倩 乌东北 包伯荣 《Journal of Shanghai University(English Edition)》 CAS 2009年第1期72-75,共4页
The synergistic extraction of Pr^3+ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono- 2-ethylhexyl ester (P507, HL) and 8-Hydroxyquinoline (HQ) in heptane was investigated. The effect o... The synergistic extraction of Pr^3+ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono- 2-ethylhexyl ester (P507, HL) and 8-Hydroxyquinoline (HQ) in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr^3+ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration oil extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr^3+. 展开更多
关键词 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester 8-hydroxyquinoline (HQ) synergistic extraction praseodymium
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沸石基咪唑盐框架8纳米材料的活性氧双向调控:从肿瘤治疗、抗菌到细胞保护
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作者 王菘芃 刘玉三 +4 位作者 于焕英 高晓丽 徐英江 张晓明 刘敏 《中国组织工程研究》 北大核心 2026年第8期2033-2043,共11页
背景:沸石基咪唑盐框架8及其衍生物凭借优异的药物控释能力在组织工程领域展现出广泛的应用潜力。目的:综述沸石基咪唑盐框架8及其改性材料在活性氧生成与清除中的作用机制,探讨它们在抗肿瘤、抗菌及组织保护领域的应用潜力,分析未来发... 背景:沸石基咪唑盐框架8及其衍生物凭借优异的药物控释能力在组织工程领域展现出广泛的应用潜力。目的:综述沸石基咪唑盐框架8及其改性材料在活性氧生成与清除中的作用机制,探讨它们在抗肿瘤、抗菌及组织保护领域的应用潜力,分析未来发展方向与挑战。方法:由第一作者通过中国知网、PubMed等数据库检索2000-2024年相关文献,中文检索关键词为“沸石基咪唑盐框架8,活性氧,抗菌,抗肿瘤,活性氧吸收,活性氧平衡,组织修复”,英文检索关键词为“ZIF-8,ROS,antibacterial,antitumor,ROS absorption,Balance of ROS,Tissue regeneration”,最终筛选69篇高质量文献进行综述分析。结果与结论:通过调控沸石基咪唑盐框架8及其改性材料的带隙结构、优化电子转移效率可显著提升光生载流子的分离与迁移效率,从而增强催化反应性能,提高活性氧的产生效率,实现更高效、更具靶向性的抗肿瘤及抗菌作用;同时,采用抗氧化酶系统或表面改性技术构建的活性氧清除装置,能够精准平衡多余活性氧,实现对细胞的有效保护。这种基于带隙调控与电子转移优化的双向调控机制,为动态管理活性氧生成与清除提供了重要策略,在抗肿瘤、抗菌及组织保护等领域展现出广阔的应用前景。 展开更多
关键词 沸石基咪唑盐框架8 活性氧 活性氧调控 抗肿瘤 抗菌 组织工程
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Corrosion Inhibition Synergism between Lanthanum(Ⅲ) Ion and 8-Hydroxyquinoline for Zinc in Hydrochloric Acid 被引量:6
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作者 木冠南 唐丽斌 李学铭 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期502-506,共5页
The effects of La 3+ ion and chelate reagent 8 hydroxyquinoline on the corrosion rate of zinc in hydrochloric acid were investigated by using weight loss method and electrochemical method. It is found that in a ... The effects of La 3+ ion and chelate reagent 8 hydroxyquinoline on the corrosion rate of zinc in hydrochloric acid were investigated by using weight loss method and electrochemical method. It is found that in a specific concentration range of La 3+ ion and 8 hydroxyquinoline, the obvious corrosion inhibition synergism is obtained. The mechanism of corrosion inhibition synergism was discussed on basis of adsorption theory. 展开更多
关键词 rare earths 8 hydroxyquinoline corrosion inhibition synergism ZINC hydrochloric acid
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TD-DFT Study on the Electronic Spectrum Properties of 2,7′-(Ethylene)-bis-8-hydroxyquinoline and Its Derivatives 被引量:1
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作者 李志锋 朱元成 +1 位作者 袁焜 康敬万 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期63-69,共7页
The structures of 2,7'-(ethylene)-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet... The structures of 2,7'-(ethylene)-bis-8-hydroxyquinoline and its derivatives were optimized at the ground states using ab initio HF and B3LYP methods. At the same time, the molecular structures of the first singlet excited state for 2,7'-(ethylene)-bis-8-hydroxyqulnoline and its derivatives were optimized by CIS/6-31G(d). The absorption and emission spectra based on the above structures were obtained by the time-dependent density functional theory (TD-DFT) by the B3LYP method with the 6-31G(d) basis set. The calculated results of luminescence originate from the electronic transition from the hydroxphenol ring of 8-hydroxyquinoline A to the pyridine ring of 8-hydroxyquinoline B. Their luminescence wave bands can be tuned by different substituents on the ligand of 8-hydroxyquinoline. 展开更多
关键词 8-hydroxyquinolinolinato derivative electron spectrum excited state TD-DFT
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Bipolar resistive switching based on bis(8-hydroxyquinoline) cadmium complex:Mechanism and non-volatile memory application
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作者 王颖 杨汀 +3 位作者 谢吉鹏 吕文理 范国莹 刘肃 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期467-472,共6页
Stable and persistent bipolar resistive switching was observed in an organic diode with the structure of indium-tin oxide (ITO)/bis(8-hydroxyquinoline) cadmium (Cdq2)/Al. Aggregate formation and electric field d... Stable and persistent bipolar resistive switching was observed in an organic diode with the structure of indium-tin oxide (ITO)/bis(8-hydroxyquinoline) cadmium (Cdq2)/Al. Aggregate formation and electric field driven trapping and detrapping of charge carriers in the aggregate states that lie in the energy gap of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the organic molecule were proposed as the mechanism of the observed bipolar resistive switching, and this was solidly supported by the results of AFM investigations. Repeatedly set, read, and reset measurements demonstrated that the device is potentially applicable in non-volatile memories. 展开更多
关键词 resistive switching MEMORY AGGREGATION bis(8-hydroxyquinoline cadmium
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Synthesis and Structural Characterization of [Co(Q)_2(H_2O)_2](Q=8-Hydroxyquinoline Ion)
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作者 胡长文 王春秀 +3 位作者 李晖 牛学丽 潘万龙 龚云 《Journal of Beijing Institute of Technology》 EI CAS 2006年第2期221-224,共4页
The single crystal of bi(8-hydroxyquinoline) bihydrated cobalt (Ⅱ) complex, [ Co(Q)2 (H2O2 ] (Q = 8-hydroxyquinoline ion), has been synthesized by general method and structurally characterized by single crys... The single crystal of bi(8-hydroxyquinoline) bihydrated cobalt (Ⅱ) complex, [ Co(Q)2 (H2O2 ] (Q = 8-hydroxyquinoline ion), has been synthesized by general method and structurally characterized by single crystal X-ray diffraction. Crystal data: C18H16CoN2O4, monoclinic, C2/c, α = 1.336 2(4) nm, b = 0.941 2(3) nm, c = 1.354 3(4) nm, β= 109.672(4)°, Z = 4. In the complex, Co( Ⅱ ) ion is six-coordinated, forming a distorted octahedron. H-bonding and π-π stacking interaction play a significant role to form and stabilize the three-dimensional structure. 展开更多
关键词 crystal structure π-π stacking hydrogen bonding Co( complex 8-hydroxyquinoline
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Theoretical Studies on the Ground State and Excited State of 2,7′- (Ethylene)-bis-8-hydroxyquinoline
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作者 Hui-xue Li Su-juan Pan +1 位作者 Xiao-feng Wang Tai Xiao 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第3期263-269,共7页
2,7′-(Ethylene)-bis-8-hydroxyquinoline was optimized with DFT/B3LYP and ab initio HF methods, so ion- ization potential and electron affinity could be determined. Absorption spectrum was calculated by ZINDO and TD-... 2,7′-(Ethylene)-bis-8-hydroxyquinoline was optimized with DFT/B3LYP and ab initio HF methods, so ion- ization potential and electron affinity could be determined. Absorption spectrum was calculated by ZINDO and TD-DFT. CIS method was used to calculate the S1 excited states of the compound and afterwards the emission spectrum was computed. When the solvent effect was taken into account, the computed results show encouraging agreement with known experimental data. The results of analyzing the relationship between the energies and absorption spectra indicate that the ability to transporting electrons is strengthened compared with 8-hydroxyquinoline and that absorption and emission spectra are red-shifted. The intramoleeular reor- ganization energy of tris(2,7′-(ethylene)-bis-8-hydroxyquinoline)-aluminum implies its electron transporting property is worse than tris(8-hydroxyquinoline)-aluminum. The predicted maximum emission wavelength is red-shifted compared with tris(8-hydroxyquinoline)-aluminum. 展开更多
关键词 2 7′(Ethylene)-bis-8-hydroxyquinoline Absorption spectrum Emission spectrum Densityfunctional theory
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A Hydrogen Bond Stabilized 3D Network Built from Pyrazine-2,3,5,6-tetracarboxylic Acid and 8-Hydroxyquinoline
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作者 徐峰 魏振宏 +2 位作者 黄祥雷 梅应轩 蔡琥 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第12期1845-1850,共6页
8-Hydroxyquinoline salt of pyrazine-2,3,5,6-tetracarboxylic acid [HQ]2[H2pztc]· 2H2O (1) was prepared and characterized by single-crystal X-ray diffraction, NMR, IR, TGA, elemental analysis and fluorescent meas... 8-Hydroxyquinoline salt of pyrazine-2,3,5,6-tetracarboxylic acid [HQ]2[H2pztc]· 2H2O (1) was prepared and characterized by single-crystal X-ray diffraction, NMR, IR, TGA, elemental analysis and fluorescent measurements. Compound 1 crystallizes in orthorhombic, space group Pbcn with a = 9.953(3), b = 15.966(3), c = 16.081(5) A, V = 2555.5(13) A3, Z = 4, μ = 0.122 mm^-1, Dc = 1.514 Mg/m3, T= 296(2) K, C26H22N4O12, Mr = 582.48, F(000) = 1208, S = 1.006, R = 0.0448 and wR = 0.1149. Compound 1 has a three-dimensional (3D) network, in which pyra- zine-2,3,5,6-tetracarboxylic acids build up two-dimensional (2D) sheets and 8-hydroxyquinoline cations and water molecules act as pillars to connect the 2D sheets into an extended 3D network through strong intermolecular hydrogen bonding and π…π stacking interactions. Especially, a very short O-H…O hydrogen bond (O…O 2.470(2) A) between two neighboring [H2pztc] anions was observed. 展开更多
关键词 pyrazine-2 3 5 6-tetracarboxylic acid 8-hydroxyquinoline hydrogen bond
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基于改进YOLOv8的葡萄叶病害检测轻量化算法研究
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作者 杨增锟 姜宏 章翔峰 《农机化研究》 北大核心 2026年第4期181-188,共8页
针对葡萄叶病害识别算法中精度与检测速度难以平衡的问题,提出一种基于改进YOLOv8的轻量化检测算法YOLO-UCES。首先,YOLO-UCES引入通用倒置卷积融合模块(C2f_UIB),替换原模型的C2f模块,通过多分支特征处理与轻量化卷积操作实现高效的特... 针对葡萄叶病害识别算法中精度与检测速度难以平衡的问题,提出一种基于改进YOLOv8的轻量化检测算法YOLO-UCES。首先,YOLO-UCES引入通用倒置卷积融合模块(C2f_UIB),替换原模型的C2f模块,通过多分支特征处理与轻量化卷积操作实现高效的特征提取与融合,增强对小目标的检测能力;其次,算法采用高效跨尺度特征融合网络结构(CCFM),替换原颈部网络,进行跨通道信息整合,促进多尺度融合;再次,在主干网络中增加高效多头注意力机制(EMA),降低计算复杂度的同时实现全局特征的建模和显著性增强,进一步增强对目标的检测能力;最后,替换原模型的检测头为融合自注意力机制的探头(Detect_SA),在保持高效计算的同时实现空间信息的有效保留与特征增强。试验结果表明:YOLO-UCES模型的准确率达到92.0%,平均精度达到93.1%。模型参数量和浮点数计算量分别降低至1.34×10^(6)和4.1 G,检测速度提升至84 f/s。与原YOLOv8模型相比,改进后的模型在准确率上提高2.6个百分点,平均精度提升0.9个百分点,参数量和计算量分别降低55.5%和49.4%,检测速度提高7 f/s。综上所述,YOLO-UCES能够很好地解决检测精度与检测速度难以平衡的问题。 展开更多
关键词 葡萄叶病害 目标检测 轻量化 YOLOv8
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