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The Prevalence and Clinical Significance of the Centromere Protein-F-Like Immunofluorescence Staining Pattern in a Large ANA-positive Cohort
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作者 SU Zhenzhen ZHANG Feng +7 位作者 ZHANG Lijing HAYISAER YEERKEN YANG Bin HU Jing WANG Li GAO Xuedan ZHANG Junlong HUANG Zhuochun 《四川大学学报(医学版)》 北大核心 2026年第2期473-481,共9页
Objective To investigate the prevalence and clinical significance of the centromere protein-F-like(CENP-F-like)immunofluorescence staining pattern in a large patient cohort and through literature review.Methods We ret... Objective To investigate the prevalence and clinical significance of the centromere protein-F-like(CENP-F-like)immunofluorescence staining pattern in a large patient cohort and through literature review.Methods We retrospectively analyzed antinuclear antibody(ANA)immunofluorescence assay results from 191274 patients at West China Hospital of Sichuan University between March 2018 and November 2020.Specific immunological markers were tested in sera with CENP-F-like patterns.Additionally,a narrative review of seven relevant studies was performed for comparison.Results In Southwest China,ANA positivity was found in 32.09%of patients,with the CENP-F-like pattern detected in 0.015%of all cases and 0.05%of ANA-positive individuals.The CENP-F-like pattern appeared predominantly at titers≥1∶320,most often in isolation(68.97%),but also mixed with cytoplasmic speckled patterns.Patients with cancers accounted for the highest proportion(31.03%),including solid tumors and hematologic malignancies.Metastasis was observed in patients with solid tumors,while graft-versus-host disease(GVHD)occurred in those with hematologic malignancies post-transplantation.Autoimmune diseases(AIDs)were diagnosed in 20.69%of cases,all showing disease-specific autoantibodies.These findings were broadly consistent with previous reports and suggest a possible association between the CENP-F-like pattern and malignancies.Conclusion The CENP-F-like pattern is rare in ANA tests but may be associated with clinically important conditions,particularly cancers and AIDs.The occurrence of metastasis and GVHD in patients with this pattern highlights its potential clinical relevance,and concurrent autoantibodies may assist in diagnosing AIDs. 展开更多
关键词 Antibodies antinuclear Fluorescent antibody technique indirect Clinical relevance NEOPLASMS Autoimmune diseases
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Bipyridine-bridged Φ-shaped cyclo[8]thiophene[2]pyrrole: Synthesis and fluorescence properties
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作者 Yue Li Qianyu Ding +7 位作者 Wansheng Liu Yimeng Sun Liyao Liu Ye Zou Yutao Cui Jia Zhu Chongan Di Daoben Zhu 《Chinese Chemical Letters》 2026年第2期512-516,共5页
Cyclo[n]Thiophenes(CnTs)are a distinctive class of π-conjugated macrocyclic molecules that have attracted growing attention owing to their structural aesthetics and organic electronic characteristics.However,the deve... Cyclo[n]Thiophenes(CnTs)are a distinctive class of π-conjugated macrocyclic molecules that have attracted growing attention owing to their structural aesthetics and organic electronic characteristics.However,the development of CnTs has been largely impeded by inefficient synthetic route.In this work,we employ a bridge strategy using bipyridine as bridge to link two quaterthiophene units resulting in Φ-shaped bicyclosystem.This strain-retaining approach improves the synthesis efficiency of the macrocycles.Two new macrocyclic molecules,(4T-2hexyl-2Me)_(2)-DPBP and(4T-2hexyl)_(2)-DPBP,were successfully synthesized in total yield 17%and 16%,respectively.Single-crystal structure of(4T-2hexyl-2Me)_(2)-DPBP reveals that the bipyridine bridge is orthogonally strapped by two quaterthiophene units.Notably,both compounds exhibit aggregation-induced emission enhancement(AIEE)behavior-an unprecedented feature among CnT-based macrocycles.Theoretical calculations reveal that this AIE phenomenon originates from the restriction of intramolecular motion(RIM)in the aggregated state,which suppresses the non-radiative decay channels.These results demonstrate a generalized strategy for the synthesis of functionalπ-conjugated macrocyclic molecules based fluorescent materials. 展开更多
关键词 Macrocycles OLIGOTHIOPHENES CNTS fluorescence AIEE
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Clinical applications of indocyanine green fluorescence for the treatment of hepatocellular carcinoma
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作者 Gaetano Piccolo Matteo Barabino +2 位作者 Laura Benuzzi Giampaolo Formisano Paolo Pietro Bianchi 《World Journal of Gastrointestinal Oncology》 2026年第1期20-27,共8页
Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves ... Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves targeting superficial tumors in patients with macronodular cirrhosis and an irregular liver surface.In a minimally invasive setting,the lack of tactile feedback on the hepatic surface makes detecting subcapsular HCC with ultrasound alone challenging.ICG fusion images can mimic the tactile feedback of the hand and act as an ultrasound booster.ICG fluorescence can be used to evaluate tumor residues after minimally invasive thermal ablation.ICG fluorescence imaging can also be used to identify the grade of HCC early on and evaluate the microinvasive component. 展开更多
关键词 Indocyanine green fluorescence Hepatocellular carcinoma Minimally invasive liver resection Laparoscopic thermal ablation fluorescence patterns Tumour characteristics
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Structural phase transition and quasi-layered active-ion distribution suppress concentration quenching in Tb^(3+)-activated KBi(MoO_(4))_(2)
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作者 Mengyu Zhang Shujing Pan +4 位作者 Haitang Hu Wenzhi Su Yong Zou Shoujun Ding Qingli Zhang 《Chinese Physics B》 2026年第1期295-304,共10页
Conventional Tb^(3+)-doped phosphors typically suffer from concentration quenching once the doping level exceeds a critical threshold.Consequently,the development of Tb^(3+)phosphors with intrinsic resistance to conce... Conventional Tb^(3+)-doped phosphors typically suffer from concentration quenching once the doping level exceeds a critical threshold.Consequently,the development of Tb^(3+)phosphors with intrinsic resistance to concentration quenching has become a key research focus.In this work,we successfully synthesized KBi(MoO_(4))_(2):x Tb^(3+)(x=0-100 at%)(denoted as KBM:x Tb^(3+))phosphors via a high-temperature solid-state reaction.Remarkably,no concentration quenching was observed across the entire doping range.This anti-quenching behavior originates from the large Tb^(3+)-Tb^(3+)interionic distance(>5Å)inherent to the quasi-layered crystal structure,which effectively suppresses multipole-interaction-mediated energy migration.At full Tb^(3+)substitution(x=100 at%),the material undergoes a structural phase transition from the monoclinic KBM phase to the triclinicα-KTb(MoO_(4))_(2)(α-KTM)phase.Theα-KTM phosphor exhibits excellent thermal stability(activation energy=0.6129 eV)and a single-exponential decay profile,whereas KBM:x Tb^(3+)(x<100%)display double-exponential decay behaviors,attributed to dual energy transfer pathways.These findings provide new insights into the luminescence mechanisms of high-concentration rare-earth-doped systems and offer guidance for designing nextgeneration anti-quenching phosphors. 展开更多
关键词 Tb^(3+)doping layered crystal structure anti-concentration quenching structural phase transition
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Highly sensitive and multi-response Zn-MOF fluorescence sensor: Design, synthesis, and detection of 4-nitrophenol, Cu^(2+), and pyrimethanil
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作者 LIU Fan CHEN Xiaoli +4 位作者 REN Jing LEI Yantao CUI Huali YANG Hua WANG Jijiang 《无机化学学报》 北大核心 2026年第4期872-882,共11页
Based on 4'-(1H-tetrazol-5-yl)-[1,1'-biphenyl]-2,4,6-tricarboxylic acid(H_(4)bta)ligand,zinc metal-organic framework(Zn-MOF):{[Zn_(2)(bta)(bpy)_(2)(H_(2)O)]·1.5H_(2)O}_(n)(bpy=2,2'-bipyridine)was desi... Based on 4'-(1H-tetrazol-5-yl)-[1,1'-biphenyl]-2,4,6-tricarboxylic acid(H_(4)bta)ligand,zinc metal-organic framework(Zn-MOF):{[Zn_(2)(bta)(bpy)_(2)(H_(2)O)]·1.5H_(2)O}_(n)(bpy=2,2'-bipyridine)was designed and synthesized by hydrothermal method.Its structure was characterized by elemental analysis,IR spectra,X-ray single crystal diffraction,etc.The asymmetric unit of Zn-MOF contains two crystallographically independent Zn^(2+)ions.Through the connection of Zn^(2+)ions via H_(4)bta,a 1D double-layer network structure is formed.Adjacent double-layer networks further form a 2D supramolecular network through hydrogen bonding.Notably,Zn-MOF exhibited excellent fluorescence properties and could efficiently and sensitively detect various water pollutants:4-nitrophenol(4-NP),Cu^(2+),and pyrimethanil(Pth).Additionally,the mechanism of fluorescence sensing was investigated.CCDC:2432230. 展开更多
关键词 4'-(1H-tetrazol-5-yl)-[1 1'-biphenyl]-2 4 6-tricarboxylic acid crystal structure fluorescence sensing
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In vivo second near-infrared fluorescence and ratiometric photoacoustic dual-modality imaging of glutathione
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作者 Yu Zhang Shan Lei +7 位作者 Yuantao Pan Chao Zhao Qiang Liu Yumeng Wu Yurong Liu Meng Li Peng Huang Jing Lin 《Chinese Chemical Letters》 2026年第2期303-307,共5页
The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we develope... The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we developed in vivo second near-infrared(NIR-II)window fluorescence(FL)and ratiometric photoacoustic(RPA)dual-modality imaging of GSH using a GSH-activatable probe(LET-14).LET-14 was synthesized based on a rhodamine hybrid xanthene skeleton with a FL shielding 2,4-dinitrobenzene sulfonyl group that can be specifically cleaved by GSH,thus resulting in a markedly bathochromic-shift absorption,a 6.5-fold increase in NIR-II FL intensity(FL_(920))and a 13-fold increase in RPA signal(PA_(880)/PA_(705))in vitro.Intriguingly,LET-14 exhibits good selectivity and sensitivity for NIR-II FL and RPA dual-modality imaging of GSH in 4T1 tumor-bearing mouse model.Our findings develop an in vivo detection tool of GSH,which has great potential in the field of cancer diagnosis. 展开更多
关键词 GLUTATHIONE In vivo Second near-infrared dye fluorescence imaging Ratiometric photoacoustic imaging
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Mapping vegetation phenology and its response to climate change in Southwest China using solar-induced chlorophyll fluorescence
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作者 TANG Feng GE Zhongxi +5 位作者 TANG Bohui FANG Liuyang ZHANG Zhen FAN Dong CHEN Junyi ZHU Xinming 《Journal of Mountain Science》 2026年第1期97-117,共21页
Accurate phenological information is essential for measuring ecosystem dynamics and carbon uptake.Southwest China is one of the country's largest terrestrial carbon sink regions and plays a crucial role in carbon ... Accurate phenological information is essential for measuring ecosystem dynamics and carbon uptake.Southwest China is one of the country's largest terrestrial carbon sink regions and plays a crucial role in carbon peaking and neutrality.However,its complex terrain,fragile ecosystem,and variable climate challenge carbon sink stability.Vegetation phenology significantly impacts carbon absorption and release,making accurate phenological data essential for understanding carbon sequestration dynamics.The widespread distribution of evergreen forests and their weak seasonal variation in canopy introduce significant uncertainties in extracting phenology using traditional remote sensing information in this region.These limitations can lead to inaccurate assessments of carbon sink dynamics.Therefore,precise phenology extraction and analysis are vital for improving ecosystem dynamics and the carbon cycle in Southwest China.Firstly,we employed different ways to evaluate the ability of solar-induced chlorophyll fluorescence(SIF)and traditional remote sensing information to extract phenology.Secondly,based on SIF,we analyzed the spatial and temporal changes in the start of the growing season(SOS),the end of the growing season(EOS),and the length of the growing season(LOS)from 2001 to 2020.Finally,we systematically analyzed the response of SOS and EOS to five preseason climatic factors.The results showed that(1)SIF outperformed traditional remote sensing information in extracting phenology.(2)Vegetation phenology exhibited significant spatial heterogeneity.Moreover,SOS,EOS,and LOS showed trends of advancement,delay,and extension both overall and across all vegetation types.(3)Precipitation was the main factor influencing SOS,while surface downward solar radiation and mean temperature were the main factors affecting EOS,and the phenology of different vegetation types showed a great difference in response to preseason climate factors.These findings improve our understanding of vegetation phenology and its dynamics over Southwest China. 展开更多
关键词 Carbon stability Mountain area Vegetation phenology Evergreen vegetation Solar induced chlorophyll fluorescence
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A review on solar-induced chlorophyll fluorescence of vegetation and its ecological process modeling
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作者 Jian Qin Zhuoying Deng +3 位作者 Shaoqiang Wang Jinghua Chen Pin Fu Chuobo Huang 《Ecological Frontiers》 2026年第1期55-67,共13页
Accurately assessing the carbon sequestration capacity of forests is crucial for mitigating climate change.Traditional methods for estimating Gross Primary Productivity(GPP)of vegetation involve significant uncertaint... Accurately assessing the carbon sequestration capacity of forests is crucial for mitigating climate change.Traditional methods for estimating Gross Primary Productivity(GPP)of vegetation involve significant uncertainties.As a novel remote sensing approach,Solar-Induced chlorophyll Fluorescence(SIF)is directly related to photosynthesis and has demonstrated strong correlations with GPP across various ecosystems,climate zones,and spatial scales.Current GPP estimation methods based on SIF include Light Use Efficiency(LUE)models,the SCOPE process models,and the latest mechanistic light response(MLR)models.Future research should focus on improving the mechanistic understanding of SIF-related processes and promoting the integration of multi-source remote sensing data with SIF-based modeling to enhance the accuracy and universality of GPP estimation. 展开更多
关键词 Solar-induced chlorophyll fluorescence Process models PHOTOSYNTHESIS Gross primary productivity FLUX Remote sensing Terrestrial ecosystems
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Theoretical study on the thermally activated delayed fluorescence,and efficiency roll‑off characteristics of a series of blue and blue‑green Ir(Ⅲ)complexes
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作者 QIN Zhengkun BAO Lixin +4 位作者 ZHANG Yunkai CUI Lin WANG Jinyu WANG Yuhao SONG Mingxing 《无机化学学报》 北大核心 2026年第2期365-374,共10页
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc... A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine. 展开更多
关键词 organic light‑emitting diodes Ir(Ⅲ)complex time‑dependent density functional theory thermal activation delayed fluorescence property efficiency roll‑off effect
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From Algorithm to Expert:RLHF-Guided Vision-Language Model for 3D-EEM Fluorescence Spectroscopy Matching
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作者 Chenglong Lu Jiehui Li +5 位作者 Tonglin Chen Changhua Zhou Yixin Fan Xinlin Ren Ziyi Ju Wei Wang 《Computers, Materials & Continua》 2026年第5期1883-1900,共18页
Existing methods for tracing water pollution sources typically integrate three-dimensional excitationemission matrix(3D-EEM)fluorescence spectroscopy with similarity-based matching algorithms.However,these approaches ... Existing methods for tracing water pollution sources typically integrate three-dimensional excitationemission matrix(3D-EEM)fluorescence spectroscopy with similarity-based matching algorithms.However,these approaches exhibit high error rates in borderline cases and necessitate expert manual review,which limits scalability and introduces inconsistencies between algorithmic outputs and expert judgment.To address these limitations,we propose a large vision-language model(VLM)designed as an“expert agent”to automatically refine similarity scores,ensuring alignment with expert decisions and overcoming key application bottlenecks.The model consists of two core components:(1)rule-based similarity calculation module generate initial spectral similarity scores,and(2)pre-trained large vision-language model fine-tuned via supervised learning and reinforcement learning with human feedback(RLHF)to emulate expert assessments.To facilitate training and evaluation,we introduce two expert-annotated datasets,Spec1k and SpecReason,which capture both quantitative corrections and qualitative reasoning patterns,allowing the model to emulate expert decision-making processes.Experimental results demonstrate that our method achieves 81.45%source attribution accuracy,38.24%higher than rule-based and machine learning baselines.Real-world deployment further validates its effectiveness. 展开更多
关键词 Vision-language model reinforcement learning with human feedback pollution source tracing 3D fluorescence spectroscopy
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Elastomer Doping Strategy for High-efficiency Stretchable Thermally Activated Delayed Fluorescence Polymer Organic Light-emitting Diodes
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作者 Zhao Yang Wen-Kang Shi +9 位作者 Zhi-Hao Shao Zi-Han Xiong Yi-Fan Li Ming-Liang Zhu Wei Wen Cheng Li Long-Bin Ren Zhi-Yuan Zhao Yun-Long Guo Yun-Qi Liu 《Chinese Journal of Polymer Science》 2026年第4期970-979,I0010,共11页
The increasing demand for flexible displays and wearable electronics has driven extensive efforts to develop stretchable organic lightemitting diodes(OLEDs).A critical challenge in this field is the creation of emissi... The increasing demand for flexible displays and wearable electronics has driven extensive efforts to develop stretchable organic lightemitting diodes(OLEDs).A critical challenge in this field is the creation of emissive layers that combine high efficiency with mechanical robustness.Thermally activated delayed fluorescence(TADF)materials have attracted significant attention as third-generation emitters capable of achieving 100%internal quantum efficiency;however,their application in stretchable OLEDs has been limited.In this study,we propose an elastomer doping strategy.Polyurethane(PU)is incorporated into TADF polymers to improve their mechanical flexibility while maintaining a high luminescent efficiency.The resulting composite films exhibited excellent TADF characteristics and remarkable stretchability(75%).OLEDs fabricated from these materials achieved a maximum external quantum efficiency(EQE)of 14.26%and a peak luminance of 73570 cd·m^(-2),with the PUdoped devices showing a significantly suppressed efficiency roll-off.Additionally,a fully stretchable OLED architecture was designed and operated under tensile strain to maintain stable electroluminescent performance.These results demonstrate that elastomer doping is an effective strategy for balancing the mechanical compliance with optoelectronic performance,offering a promising pathway for the development of high-performance stretchable OLEDs for flexible electronics. 展开更多
关键词 Thermally activated delayed fluorescence(TADF) Elastomer doping Stretchable OLEDs Polyurethane(PU) Flexible electronics
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Damage mechanism of Si_(3)N_(4)-bonded SiC bricks in sloped zone of dry quenching coke ovens under N_(2)-CO_(2)-CO-H_(2)-O_(2) atmosphere
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作者 Jian-Lei Cao Ding Chen +5 位作者 Wen-Jie Yuan Ao Huang Lv-Ping Fu Yong-Shun Zou Hua-Zhi Gu Tu Long 《Journal of Iron and Steel Research International》 2026年第1期125-132,共8页
The Si_(3)N_(4)-bonded silicon carbide(SiC)bricks in the sloped zone of dry quenching coke ovens support the weight of upper refractory materials and equipment.These bricks endure frequent temperature fluctuations and... The Si_(3)N_(4)-bonded silicon carbide(SiC)bricks in the sloped zone of dry quenching coke ovens support the weight of upper refractory materials and equipment.These bricks endure frequent temperature fluctuations and intense abrasion from coke dust,demanding extremely high performance.After three years of service,an analysis of the Si_(3)N_(4)-bonded SiC bricks revealed that oxidation,which reduces thermal shock resistance,is the primary cause of degradation.In the unused Si_(3)N_(4)-bonded SiC bricks,short columnar β-Si_(3)N_(4) forms an interwoven network around SiC particles and contains a small amount of plate-like Si_(2)N_(2)O.Under the complex N_(2)(84.42 vol.%)-CO_(2)(10.44 vol.%)-CO(4.43 vol.%)-H_(2)(0.56 vol.%)-O_(2)(0.15 vol.%)atmosphere in the dry quenching coke oven,O_(2)(0.15 vol.%)exhibits a stronger oxidizing effect than CO_(2)(10.44 vol.%)and CO(4.43 vol.%),making it the primary oxidizing agent.The short columnarβ-Si_(3)N_(4) is more susceptible to oxidation than the particulate SiC.Based on thermodynamic and kinetic analyses,the chemical stability of the phases in Si_(3)N_(4)-bonded SiC bricks ranks from strongest to weakest as follows:Si_(2)N_(2)O,SiC,Si_(3)N_(4).Future development of Si_(2)N_(2)O-bonded SiC bricks could improve the longevity of refractory materials in the sloped zone of dry quenching coke ovens. 展开更多
关键词 Dry quenching coke oven Si_(3)N_(4)-bonded SiC brick N_(2)-CO_(2)-CO-H_(2)-O_(2)atmosphere Oxidation Thermal shock resistance
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STUDY ON THE MECHANISM OF FLUORESCENCE QUENCHING OF NITROCOMPOUNDS FOR OXAZOLES *
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作者 齐欣 杨学茹 +3 位作者 刘东志 游得华 王淑丽 张文勤 《Transactions of Tianjin University》 EI CAS 1998年第1期54-57,共4页
The mechanism of nitrocompounds quenching of the fluorescence of 5, 5′ dipheny1 2, 2′ bisoxazole (POOP) and trans 1, 2 bis [2 (5 phenyloxazolyl)] ethene (POEOP) has been studied. It was found that the fluores... The mechanism of nitrocompounds quenching of the fluorescence of 5, 5′ dipheny1 2, 2′ bisoxazole (POOP) and trans 1, 2 bis [2 (5 phenyloxazolyl)] ethene (POEOP) has been studied. It was found that the fluorescence of oxazoles was quenched mainly by the absorption competition and radiationless energy transfer of nitrocompounds. The fluorescence quenching rate constants of nitrobenzene and nitromethane are 3.0×10 10 L·mol -1 ·s -1 and 1.5×10 8 L·mol -1 ·s -1 respectively for POEOP. This remarkable difference was explicated. 展开更多
关键词 fluorescence quenching nitrocompound OXAZOLES energy transfer absorption competition
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Aggregation-dependence of Optical Properties and Fluorescence Quenching of a Water-soluble Poly(phenylene ethynylene)
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作者 Ming Hui YU Hai Yang GAN +4 位作者 Fang HE Yan Li TANG Da Gui ZHENG Shu WANG Yu Liang LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第5期671-674,共4页
The solvent and surfactant-dependent aggregation behaviors of the anionic poly(phenylene ethynylene) were studied and used to tune optical properties and fluorescence quenching efficiency.
关键词 Conjugated polymers AGGREGATION optical properties fluorescence quenching.
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Ultrafast Fluorescence Quenching in LnFe(CN)_6·4H_2O
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作者 孟建新 戴德昌 +1 位作者 李润华 周建英 《中山大学学报论丛》 1997年第5期42-45,共4页
对LnFe(CN)6·4H2O(Ln=Eu,Tb)体系的吸收光谱和荧光光谱的研究表明,两配合物的中Eu3+和Tb3+离子的荧光发生强烈猝灭,即使是用高功率激光直接激发Eu3+的7F0→5D0跃迁也是如此,表明该体... 对LnFe(CN)6·4H2O(Ln=Eu,Tb)体系的吸收光谱和荧光光谱的研究表明,两配合物的中Eu3+和Tb3+离子的荧光发生强烈猝灭,即使是用高功率激光直接激发Eu3+的7F0→5D0跃迁也是如此,表明该体系中稀土离子的荧光寿命非常短,有可能满足室温超快相干控制的要求. 展开更多
关键词 LnFe(CN)6·4H2O 荧光猝灭 相干控制
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Fluorescence quenching method for the determination of catechol with gold nanoparticles and tyrosinase hybrid system 被引量:4
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作者 Martin M.F.Choi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期346-348,共3页
The determination method of catechol by fluorescence quenching was developed.The assay was based on the combination of the unique property of gold nanoparticles with tyrosinase enzymatic reaction.In the presence of ty... The determination method of catechol by fluorescence quenching was developed.The assay was based on the combination of the unique property of gold nanoparticles with tyrosinase enzymatic reaction.In the presence of tyrosinase,the fluorescence of gold nanoparticles was quenched by catechol which can be employed to detect catechol.Under the optimal conditions,a linear range 5.0×10^(-7)-1.0×10^(-3) mol L^(-1) and a detection limit 1.0×10^(-7) mol L^(-1) of catechol were obtained.o-Quinone intermediate produced... 展开更多
关键词 Gold nanoparticles TYROSINASE CATECHOL fluorescence quenching
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Fluorescence Quenching of a Novel Eu(Ⅲ) Coordination Compound for the Detection of Trace Amounts of Water: Synthesis, Structure and Photoluminescent Property 被引量:2
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作者 王秋华 吴叶文 宋莉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1341-1347,共7页
A novel luminescent coordination compound Eu(TTA)3(DEDAF)(1, TTA = 1,1,1-trifluoro-3-(2-thenoyl)acetone, DEDAF = 9,9-diethyl-4,5-diazafluoren) has been synthesized and fully characterized by infrared spectrum,... A novel luminescent coordination compound Eu(TTA)3(DEDAF)(1, TTA = 1,1,1-trifluoro-3-(2-thenoyl)acetone, DEDAF = 9,9-diethyl-4,5-diazafluoren) has been synthesized and fully characterized by infrared spectrum, elemental analysis, UV-vis spectrum, etc. X-ray single-crystal diffraction analysis reveals that compound 1 shows a mononuclear structure with the europium atom in coordinating to one DAF and three TTA ligands. The mononuclear structure units are assembled into a 3-D polymer by hydrogen bonds and π-π interactions. Photoluminescent property of 1 was investigated in detail at room temperature. Complex 1 emits strong red luminescence. However, it could be quenched even by small amount of water. The fluorescence intensity at 614 nm decreases linearly with the water content increasing(vol% in acetonitrile) in the range of 0.025~0.2% under 278 nm excitation. Thermogravimetric analysis has also been studied, which demonstrates good thermal stability of 1. 展开更多
关键词 europium coordination compound 9 9-diethyl-4 5-diazafluoren photoluminescent property fluorescence quenching water detection
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Fluorescence Quenching of Anthracene by N,N-Diethylaniline and Phenothiazine in Triton X-100/n-C_(10)H_(21) OH/H_2O Microemulsion 被引量:1
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作者 GUO Xia XU Hui GUO Rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第4期484-488,共5页
The photo-induced electron transfer reactions of anthracene with N,N -diethylaniline(DEA) and phenothiazine(PTZ) occur in the membrane phase of a Triton X-100/ n -C 10 H 21 OH(1-decanol)/H 2O microemulsion. DEA and PT... The photo-induced electron transfer reactions of anthracene with N,N -diethylaniline(DEA) and phenothiazine(PTZ) occur in the membrane phase of a Triton X-100/ n -C 10 H 21 OH(1-decanol)/H 2O microemulsion. DEA and PTZ exist in the membrane phase of the microemulsion. Anthracene exists in the oil continuous phase of the W/O microemulsion and in the oil core and membrane phase of the O/W microemulsion. 展开更多
关键词 Electron transfer process fluorescence quenching Anthracene Phenothiazine N N -dieth\|ylaniline MICROEMULSION
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FLUORESCENCE AND ITS ENHANCEMENT OR QUENCHING OF Eu(TTA)_3 Phen LB FILMS 被引量:1
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作者 Ren Jie ZHANG Hong Guo LIU +2 位作者 Cheng Ru ZHANG Kong Zhang YANG (Institute of Colloid and Interface Chemistry, Shandong University, Jinan, 250100)Zhi Kun SI Gui Yun ZHU (Department of Chemistry, Shandong University, Jinan, 250100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第7期627-630,共4页
For the first time, LB films containing Eu(TTA)3Phen are obtained by using composite subphase. Eu(TTA)3Phen itself is dimcult to be transferred onto solid substrate.mixed or alternate LB films are prepared. Hydrogen b... For the first time, LB films containing Eu(TTA)3Phen are obtained by using composite subphase. Eu(TTA)3Phen itself is dimcult to be transferred onto solid substrate.mixed or alternate LB films are prepared. Hydrogen bonds form between Eu(TTA)3Phen and AA or TPP(-COOH). TOPO and SB have a fluorcscence enhanGement effect on Eu(TTA)3Phen. TPP(-COOH) and Fc have a fluorescence quenching effect on it. 展开更多
关键词 TTA fluorescence AND ITS ENHANCEMENT OR quenching OF Eu Phen LB FILMS LB ITS
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Determination of L-phenylalanine by cucurbit[7]uril sensitized fluorescence quenching method 被引量:3
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作者 Chang Feng Li Li Ming Du +1 位作者 Hao Wu Ying Xia Chang 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第7期851-854,共4页
The determination method of L-phenylalartine (LPA) by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril (CB [7]) with palmatine hydrochloride (PAL) reaction. In ... The determination method of L-phenylalartine (LPA) by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril (CB [7]) with palmatine hydrochloride (PAL) reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation (R.S.D) was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe. 展开更多
关键词 L-PHENYLALANINE Palmatine hydrochloride uril Fluorescent probe
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