Lipid droplet(LD) fluorescent imaging plays an important role in the detection of lipid-related diseases.Due to their poor photostability and low hydrophobicity of currently available LD imaging fluorophores,LD imagin...Lipid droplet(LD) fluorescent imaging plays an important role in the detection of lipid-related diseases.Due to their poor photostability and low hydrophobicity of currently available LD imaging fluorophores,LD imaging is limited by its short imaging period and low imaging contrast. Herein, we reasonably designed a highly lipophilic compound Cou-Flu with excellent photostability and excimer-monomer transition property. It exhibited weak excimer emission in cytoplasm, but strong monomer emission in LDs,enabling high contrast LD imaging and LD movement tracing in cells. Zebrafish imaging study demonstrated that Cou-Flu was also suitable for in vivo LD detection with excellent sensitivity. We anticipate that Cou-Flu could be widely applied to understand LD-related intracellular activities and even LD-related diseases in the future.展开更多
Many approaches have been explored to tune emission behaviors of organic luminogens.However,precise regulation of distances in dimers is seldom reported.Here,four pyrene derivatives are presented,and we precisely regu...Many approaches have been explored to tune emission behaviors of organic luminogens.However,precise regulation of distances in dimers is seldom reported.Here,four pyrene derivatives are presented,and we precisely regulate the distance between pyrene units of X2P.Its crystal manifests unusual deep-blue excimer emission at 424 nm,while the crystal of X1P with only one pyrene unit for each molecule gives sky-blue emission with a maximum emission peak at 475 nm.展开更多
In this work, the influence of discharge modes on the excimer XeCl emission (308 nm) has been studied by adding helium gas into the xenon and chlorine mixture. It is found that the transition from filament discharge t...In this work, the influence of discharge modes on the excimer XeCl emission (308 nm) has been studied by adding helium gas into the xenon and chlorine mixture. It is found that the transition from filament discharge to glow /filament - combined discharge leads to the decrease in excimer emission. We are the first one to use a flowing water film as an outer transparent electrode, and achieve a higher UV intensity, compared with the case by using a metal mesh as the outer electrode. The influence of the gas temperature both in the reactor Tg and in a discharge channel Tc on the excimer emission has been analyzed preliminarily. Finally, it has been expected that the replacement of chlorine gas Cl2 by another chlorine gas may reduce the heat generated in the discharge processes and give rise to the excimer XeCl* radiation.展开更多
A new chiral bromobinaphthol-pyrene compound was developed to achieve a green circularly polarized luminescence(CPL)from its excimer with a dissymmetry factor(|glum|)value of 4.3×10^-3 and a high quantum yieldΦF...A new chiral bromobinaphthol-pyrene compound was developed to achieve a green circularly polarized luminescence(CPL)from its excimer with a dissymmetry factor(|glum|)value of 4.3×10^-3 and a high quantum yieldΦF,solid up to 55.9%,while no CPL signals could be observed for the blue luminescence from unimolecule.Meanwhile,reversal CPL signals can be observed from both concentrated solution and solid.展开更多
On account of the advantages of organic electroluminescent materials compared with their inorganic counterparts,the development of organic electroluminescent materials is one of the hot areas of the optoelectronic mat...On account of the advantages of organic electroluminescent materials compared with their inorganic counterparts,the development of organic electroluminescent materials is one of the hot areas of the optoelectronic materials.Fluorene and its derivatives,which have an aromatic biphenyl structure with a wide energy gap in the backbones and high luminescent efficiency,have drawn much attention of ma-terial chemists and device physicists.However,one drawback of fluorene-based electroluminescent blue materials is that there is an occurrence of long wavelength emission after annealing the films in air or after operating organic light-emitting diodes for a long time.To clarify the origin of this long wave-length emission,the scientists at home and abroad have put forward all kinds of correlative explana-tions.Among the scientists,some thought it was caused by excimer-related species,while some others claimed that it was caused by the fluorenone of photooxdized fluorene.The corresponding solutions to this problem have also been proposed and the problem has been partially resolved in some degree.The present review summarizes and analyzes the progress made on the origin of long wavelength emission in fluorene-based electroluminescent blue materials at home and abroad in the past few years.Some issues to be addressed and hotspots to be further investigated are also presented and discussed.展开更多
The influence of the iodine vapour pressure on the mechanisms of XeI^＊ formation is investigated in Xe/I2 mixture by dielectric barrier discharge. The iodine vapour pressure is measured as a function of the ultraviol...The influence of the iodine vapour pressure on the mechanisms of XeI^＊ formation is investigated in Xe/I2 mixture by dielectric barrier discharge. The iodine vapour pressure is measured as a function of the ultraviolet （UV） intensity of XeI^＊ emission at 253 nm, and found that the UV intensity reaches a maximum at 0.9 Torr of iodine at a xenon pressure of 300 Torr, then decreases slowly with the iodine pressure larger than 0.9 Torr. The discharge mode transforms from a hybrid discharge at a xenon pressure of 760 Torr with 1.0 Torr of iodine to a diffuse mode at 10 Torr of iodine. These results are quite different from those of other rare-gas halogen excimers and indicate a different mechanism of XeI^＊ formation from those of other rare-gas halogen excimers.展开更多
Two piezochromic fluorescent compounds are prepared by introducing thiomethyl substituents to the peripheralpositions of two related cyano oligo(p-phenylene vinylenes) (CN-OPV). The new derivatives, namely, 1,4-bis[2-...Two piezochromic fluorescent compounds are prepared by introducing thiomethyl substituents to the peripheralpositions of two related cyano oligo(p-phenylene vinylenes) (CN-OPV). The new derivatives, namely, 1,4-bis[2-cyano-2(4-thiomethylphenyl)ethenyl]benzene (TOPV1) and 1,4-bis(1-cyano-2-(4-thiomethylphenyl)ethenyl) benzene (TOPV2), are characterized by NMR, powder X-ray diffraction data (XRD) and differential scanning calorimetric (DSC) data. UV-Vis and fluorescence spectra are also measured. TOPV1 with the cyano groups farther away from the central aromatic ring is photoluminescent, and on application of pressure exhibits a more obvious color change and higher Stokes shift than those measured for TOPV2. We also observe piezochromic aggregation-induced emission (PAIE) for TOPV2, but TOPV1 does not exhibit any PAIE.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21725505,22074016 and 81821001)。
文摘Lipid droplet(LD) fluorescent imaging plays an important role in the detection of lipid-related diseases.Due to their poor photostability and low hydrophobicity of currently available LD imaging fluorophores,LD imaging is limited by its short imaging period and low imaging contrast. Herein, we reasonably designed a highly lipophilic compound Cou-Flu with excellent photostability and excimer-monomer transition property. It exhibited weak excimer emission in cytoplasm, but strong monomer emission in LDs,enabling high contrast LD imaging and LD movement tracing in cells. Zebrafish imaging study demonstrated that Cou-Flu was also suitable for in vivo LD detection with excellent sensitivity. We anticipate that Cou-Flu could be widely applied to understand LD-related intracellular activities and even LD-related diseases in the future.
基金The authors are grateful to the National Science Foundation of China(nos.21734007 and 51973162)Hubei Province(no.2017CFA002)for financial support.
文摘Many approaches have been explored to tune emission behaviors of organic luminogens.However,precise regulation of distances in dimers is seldom reported.Here,four pyrene derivatives are presented,and we precisely regulate the distance between pyrene units of X2P.Its crystal manifests unusual deep-blue excimer emission at 424 nm,while the crystal of X1P with only one pyrene unit for each molecule gives sky-blue emission with a maximum emission peak at 475 nm.
文摘In this work, the influence of discharge modes on the excimer XeCl emission (308 nm) has been studied by adding helium gas into the xenon and chlorine mixture. It is found that the transition from filament discharge to glow /filament - combined discharge leads to the decrease in excimer emission. We are the first one to use a flowing water film as an outer transparent electrode, and achieve a higher UV intensity, compared with the case by using a metal mesh as the outer electrode. The influence of the gas temperature both in the reactor Tg and in a discharge channel Tc on the excimer emission has been analyzed preliminarily. Finally, it has been expected that the replacement of chlorine gas Cl2 by another chlorine gas may reduce the heat generated in the discharge processes and give rise to the excimer XeCl* radiation.
基金the National Natural Science Foundation of China(NSFC,Nos.21788102,21722603 and 21871083)Shanghai Municipal Science and Technology Major Project(No.2018SHZDZX03)+2 种基金‘Shu Guang’Project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation(No.19SG26)the Innovation Program of Shanghai Municipal Education Commission(No.2017-01-07-00-02-E00010)the Fundamental Research Funds for the Central Universities。
文摘A new chiral bromobinaphthol-pyrene compound was developed to achieve a green circularly polarized luminescence(CPL)from its excimer with a dissymmetry factor(|glum|)value of 4.3×10^-3 and a high quantum yieldΦF,solid up to 55.9%,while no CPL signals could be observed for the blue luminescence from unimolecule.Meanwhile,reversal CPL signals can be observed from both concentrated solution and solid.
基金the National Natural Science Foundation of China(Grant Nos:90406021,20774043and20574012)Natural Science Foundation of Jiangsu College Council(Grant No:KJD150148)Scientific Research Foundation of Nanjing University of Posts and Telecommunications(Grant No:NY206069)
文摘On account of the advantages of organic electroluminescent materials compared with their inorganic counterparts,the development of organic electroluminescent materials is one of the hot areas of the optoelectronic materials.Fluorene and its derivatives,which have an aromatic biphenyl structure with a wide energy gap in the backbones and high luminescent efficiency,have drawn much attention of ma-terial chemists and device physicists.However,one drawback of fluorene-based electroluminescent blue materials is that there is an occurrence of long wavelength emission after annealing the films in air or after operating organic light-emitting diodes for a long time.To clarify the origin of this long wave-length emission,the scientists at home and abroad have put forward all kinds of correlative explana-tions.Among the scientists,some thought it was caused by excimer-related species,while some others claimed that it was caused by the fluorenone of photooxdized fluorene.The corresponding solutions to this problem have also been proposed and the problem has been partially resolved in some degree.The present review summarizes and analyzes the progress made on the origin of long wavelength emission in fluorene-based electroluminescent blue materials at home and abroad in the past few years.Some issues to be addressed and hotspots to be further investigated are also presented and discussed.
文摘The influence of the iodine vapour pressure on the mechanisms of XeI^＊ formation is investigated in Xe/I2 mixture by dielectric barrier discharge. The iodine vapour pressure is measured as a function of the ultraviolet （UV） intensity of XeI^＊ emission at 253 nm, and found that the UV intensity reaches a maximum at 0.9 Torr of iodine at a xenon pressure of 300 Torr, then decreases slowly with the iodine pressure larger than 0.9 Torr. The discharge mode transforms from a hybrid discharge at a xenon pressure of 760 Torr with 1.0 Torr of iodine to a diffuse mode at 10 Torr of iodine. These results are quite different from those of other rare-gas halogen excimers and indicate a different mechanism of XeI^＊ formation from those of other rare-gas halogen excimers.
文摘Two piezochromic fluorescent compounds are prepared by introducing thiomethyl substituents to the peripheralpositions of two related cyano oligo(p-phenylene vinylenes) (CN-OPV). The new derivatives, namely, 1,4-bis[2-cyano-2(4-thiomethylphenyl)ethenyl]benzene (TOPV1) and 1,4-bis(1-cyano-2-(4-thiomethylphenyl)ethenyl) benzene (TOPV2), are characterized by NMR, powder X-ray diffraction data (XRD) and differential scanning calorimetric (DSC) data. UV-Vis and fluorescence spectra are also measured. TOPV1 with the cyano groups farther away from the central aromatic ring is photoluminescent, and on application of pressure exhibits a more obvious color change and higher Stokes shift than those measured for TOPV2. We also observe piezochromic aggregation-induced emission (PAIE) for TOPV2, but TOPV1 does not exhibit any PAIE.
