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Modification of single molecule fluorescence using external fields

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Frontiers of physics 2017年第5期12卷 11-25页

作者： Rui-Yun Chen guo-feng zhang Cheng-Bin Qin Yan Gao Lian-Tuan Xiao Suo-Tang Jia State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser Spectroscopy Shanxi University Taiyuan 030006 China Collaborative Innovation Center of Extreme Optics S hanxi University Taiyuan 030006 China

Controlling and manipulating the fluorescence of single fluorophores is of great interest in recent years for its potential uses in improving the performance of molecular photonics and molecular electronics, such as in organic light-emitting devices, single photon sources, organic field-effect transistors, and probes or sensors based on single molecules. This review shows how the fluorescence emission of single organic molecules can be modified using local electromagnetic fields of metallic nanostructures and electric-field-induced electron transfer. Electric-field-induced fluorescence modulation, hysteresis, and the achievement of fluorescence switch are discussed in detail.

关键词： single molecules fluorescence modification external fields

Synthesis of Fluorene-Bridged Arylene Vinylene Fluorophores： Effects of End-Capping Groups on the Optical Properties, Aggregation Induced Emission

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Chinese Journal of Chemistry 2015年第8期33卷 939-947页

作者： guo-feng zhang Tao Chen Ze-Qiang Chen Matthew P. Aldred Xianggao Meng Ming-Qiang Zhu Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan Hubei 430074 China Department of Chemistry Durham University South Road Durham DH1 3LE UK Key Laboratory of Pesticide and Chemical Biology of Ministry of Education College of Chemistry Central China Normal University Wuhan Hubei 430079 China

We have synthesized a series of fluorene-based fluorophores, in which a central fluorene core has been modified with different peripheral arylene vinylene substituents that are able to activate aggregation-induced emission （AIE） characteristics. 9,9-Dioctylfluorene doubly end-capped at the 2,7-positions with triphenylethene groups, such as 4-（2,2-diphenylvinyl）phenyl （F1-（2,2）-HTPE） and 4-（1,2-dipbenylvinyl）phenyl （F1-（1,2）-HTPE） were synthesized and compared to the tetraphenylethene analogue （F1-TPE）. Both FI-（2,2）-HTPE and F1-（1,2）-HTPE glow with a deep blue fluorescence in THF solution with emission maxima （λem） of 426 and 403 nm, respectively. The λem slightly red-shifts in the solid-state to 458 nm for F 1-（2,2）-HTPE and 437 nm for F 1-（1,2）-HTPE. The fluorescence quantum yields （ΦF） of F1-（2,2）-HTPE （ΦF=35.1%） and FI-（1,2）-HTPE （ΦF=26.2%） were found to be higher in solution compared to the near quenching of F 1-TPE （ΦF = 0.1%）. Consequently, this results in weaker AIE-stability of F1-（2,2）-HTPE （αAIE= 1.5） and F1-（1,2）-HTPE （αAIE=1.9） compared to F1-TPE （αAIE=125）, suggesting that four phenyl groups are necessary for efficient AIE-activity of these fluorene bridged arylene vinylene type materials In addition, decreasing the steric hindrance around the arylene vinylene moiety by removal of a phenyl ring is an- other method to decrease the AIE characteristics, in a similar manner to the commonly known ＂phenyl-locking＂. Non-polar triphenylethenes are poorer AlE materials than their tetraphenylethene analogues. Replacing the hydro- gen atom of F1-（2,2）-HTPE with a cyano group affords fluorene end-capped with 2,3,3-triphenylacrylonitrile （F1-TPAN）, which boosts the AIE-effect to αAIE=90.5 and red-shifts the solid-state emission （λem=528 nm） with near quenching in THF solution （ΦF= 0.12%）. X-ray crystallographic analysis of F1-TPAN indicates that the intro- duction of cyano groups can not only diminish the intramolecular steric hindrance in comparison of F1-TPE, but

关键词： aggregation-induced emission fluorene triphenylethene tetraphenylethene 2,3,3-triphenylacrylonitrile

Tracing the sources of nutrients through the Tsushima/Korea Strait

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Acta Oceanologica Sinica 2024年第6期43卷 142-152页

作者： Jing zhang Xinyu guo Lei Zhu Jianlong feng Liang Zhao Key Laboratory of Marine Resource Chemistry and Food Technology Ministry of EducationTianjin 300457China College of Marine and Environmental Science Tianjin University of Science and TechnologyTianjin 300457China Center for Marine Environmental Studies Ehime UniversityMatsuyama 790-8577Japan

The nutrients from the East China Sea(ECS) through the Tsushima/Korea Strait(TS) strongly impact the eco system of the Japan Sea(JS).The complex origins of the Tsushima Warm Current and the various nutrient sources in the ECS result in complex spatial-temporal variations in nutrients in the *** a physical-biological model with a tracking technique,we studied the effects of nutrient sources from the ECS on the *** all the nutrient sources,the Kuroshio has the highest nutrient concentrations in the *** maximum concentration occurs at the bottom,while those of rivers and atmospheric depo sition occur at the surface,and that of the Taiwan Strait occurs in the middle *** nutrient transport through the TS exhibits similar seasonal variations,as does the volume *** transport of nutrients from the Kuroshio accounts for more than 85% of the *** transport of nutrients from the Taiwan Strait is greater during autumn and *** transport of dissolved inorganic nitrogen(DIN) from both rivers and atmospheric deposition through the TS peak in *** transport cannot be equated with volume *** DIN in the less saline zone originates not only from rivers but also from atmospheric deposition and the *** transport of nutrients from the Taiwan Strait is not as significant as its volume transport in the TS.

关键词： dissolved inorganic nitrogen dissolved inorganic phosphate East China Sea Japan Sea nutrient transport

Achieving high-efficient photocatalytic persulfate-activated degradation of tetracycline via carbon dots modified MIL-101(Fe)octahedrons

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Chinese Journal of Chemical Engineering 2024年第2期66卷 298-309页

作者： Hao Yuan Xinhai Sun Shuai zhang Weilong Shi feng guo School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China

The synergistic reaction of photocatalysis and advanced oxidation is a valid strategy for the degradation of harmful antibiotic ***,carbon dots(CDs)modified MIL-101(Fe)octahedrons to form CDs/MIL-101(Fe)composite photocatalyst was synthesized for visible light-driven photocatalytic/persulfate(PS)-activated tetracycline(TC)*** electron spin resonance(ESR)spectra,scavenging experiment and electrochemical analysis were carried out to reveal that the high visible light-driven photocatalytic degradation activity of TC over CDs/MIL-101(Fe)photocatalysts is not only ascribed to the production of free active radicals in the CDs/MIL-101(Fe)/PS system(·OH,·SO_(4-),^(1)O_(2),h^(+)and·O_(2)^(-))but also attributed to the consumption of electrons caused by the PS,which can suppress the recombination of photo-generated carriers as well as strong light scattering and electron trapping effects of ***,the possible degradation pathways were proposed by analyzing intermediates via liquid chromatography-mass spectrometry *** research presents a rational design conception to construct a CDs/PS-based photocatalysis/advanced oxidation technology with high-efficient degradation activity for the remediation of organic antibiotic pollutant wastewater and for the improvement of carrier transport kinetics of photocatalysts.

关键词： Carbon dots MIL-101(Fe) Photocatalytic Persulfate activation Tetracycline degradation

Enhancing the peroxidase-like activity of MoS_(2)-based nanozymes by introducing attapulgite for antibacterial application and sensitive detection of glutathione

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Nano Research 2024年第8期17卷 7415-7426页

作者： feng feng Yihe zhang Xiao zhang Bin Mu Jiahe zhang Wenjie Qu Wangshu Tong Minmin Liang Qi An Zhanjun guo Lu Zhao Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Clay Mineral Applied Research of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Experimental Center of Advanced Materials School of Materials Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Nanozymes are next-generation of nanomaterials with enzyme-like *** particular,nanozymes with peroxidase(POD)-like activity have been utilized in various fields,including antibacterial,detection,degradation,***,their extensive applications were limited by their low catalytic activity ***,we have presented a composite nanozyme based on attapulgite(ATP)(Fe-ATP-MoS_(2)(FAM)),which exhibited enhanced POD-like activity(185.33 U·mg^(−1)),4.25 times higher than that of Fe-MoS_(2)(FM)(43.63 U·mg^(−1)).The density functional theory(DFT)calculations indicated that the addition of ATP increased the electron density of metal centers(Mo and Fe).More importantly,Michaelis–Menten kinetics revealed that the introduction of ATP significantly enhanced the binding affinities of substrates through the pores of ATP,forming a highly concentrated substrate microenvironment and thus promoting its POD-like ***,from molecular size and kinetic analysis,we proposed that the changes in substrate size before and after oxidation also significantly affected its Michaelis-constant(Km)***,we utilized FAM in the applications of highly effective antibacterial application and sensitive detection of glutathione(GSH).In conclusion,this work provides a novel approach for designing a highly efficient nanozyme based on natural mineral composites.

关键词： attapulgite peroxidase electron density affinity antibacterial

Study on the influence of curcumin on chemosensitivity of nephroblastoma cells

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Asian Pacific Journal of Tropical Medicine 2016年第8期9卷 779-782页

作者： Xiao-Yong Li Yuan-Yuan feng Wei Dan Deng Pan guo-feng zhang Xian-Liang Wang Guang-Jun Hou Department of Pediatric Surgery Children's Hospital of Zhengzhou Department of Paediatrics Children's Hospital of Zhengzhou Department of Paediatrics Maternal and Child Health Hospital of Tonglu County

Objective:To study the influence of curcumin on chemosensitivity of nephroblastoma ***:Human nephroblastoma cells line SK-NEP-1 was transplanted to the nude mice subcutaneously to establish the implantation tumor model of human nephroblastoma cells.A total of 30 tumor-bearing mice were divided into three groups of ten *** routine chemotherapy group was given vincristine(0.05 mg/mL·0.2 mL/d) and actinomycin D(15 ng/mL·0.2 mL/d) combined chemotherapy *** curcumin chemotherapy group was given the same combined chemotherapy regimens and curcumin(30 mg/kg/d) by intraperitoneal *** control group was given normal saline(NS) of the same volume by intraperitoneal *** administration would be kept for 4 weeks and 3 days a *** volumetric changes of every group were *** serum of every group in different time was collected and the VEGF content was detected by *** mice were cercrificed and the tumor tissues were stripped and weighed after 4 weeks’ *** tumor inhibition rate was *** cell proliferation activity and apoptosis rate were detected by MTT and flow cytometry *** data were statistically analyzed by SPSS ***:The tumor volume,serum VEGF content,tumor inhibition rate,cell proliferation activity and apoptosis rate of routine chemotherapy group and curcumin chemotherapy group had significant differences comparing with the control group(P<0.05) after 4-week’s *** cancer growth of curcumin chemotherapy group was obviously decreased and even tended to shrink comparing with routine chemotherapy group(χ2=15.732,P=0.007).The cell proliferation activity was significantly reduced and the apoptosis rate was significantly higher,(χ~2=9.427,P=0.012)which showing the effect of chemotherapy was ***:The chemosensitivity of nephroblastoma cells could be improved by curcumin,then the effect of preoperative adjuvant chemotherapy scheme would be enhanced,the gro

关键词： Nephroblastoma Transplanted tumor model Curcumin Chemosensitivity Vincristine

PHOTOSWITCHABLE NANOFLUOROPHORES FOR INNOVATIVE BIOIMAGING

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Journal of Innovative Optical Health Sciences 2011年第4期4卷 395-408页

作者： MING-QIANG ZHU guo-feng zhang CHONG LI YA-JING LI MATTHEW PALDRED ALEXANDER D.Q.LI Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China Department of Chemistry Washington State University PullmanWA 99164USA

Photosensitive fluorescent probes have become powerful tools in chemical biology and molecular biophysics,which are used to investigate cellular processes with high temporal and spatial ***,photosensitive fluorescent probes,including photoactivatable,photoconvertible,and photoswitchable fluorophores,have been extensively developed during the past *** photoswitchable fluorophores have received much attention because they highlight cellular events *** minireview summarizes recent advances of using reversibly photoswitchable fluorophores and their applications in innovative *** fluorophores include photoswitchable fluorescent proteins,photoswitchable fluorescent organic molecules(dyes),and photoswitchable fluorescent *** strategies have been developed to synthesize photoswitchable fluorophores,including engineering combination proteins,chemical synthesis,polymerization,and *** we concentrate on polymer nanoparticles with optically switchable emission properties:either fluorescence on/offor dualalternating-color fluorescence *** essential mechanisms of fluorescence photoswitching enable different types of photoswitchable fluorophores to change emission intensity or wavelength(color)and thus validating the basis of the fluorescence on/offor dual-color photoswitching *** the possible applications of any fluorophores are to label biological targets,followed by specific *** newly developed photoswitchable fluorophores enable super-resolution fluorescence imaging because of their photosensitive ***,we summarize the important area regarding future research and development on photoswitchable fluorescent nanoparticles.

关键词： Fluorescent molecular switches polymer nanoparticles two-photon two-photon imaging spiropyran

Radial solution of the Logarithmic Laplacian system

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 114-124页

作者： zhang Li-hong NIE Xiao-feng WANG guo-tao Bashir Ahmad School of Mathematics and Computer Science Shanxi Normal UniversityLinfen 041004China Nonlinear Analysis and Applied Mathematics(NAAM)Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia.

The paper generalizes the direct method of moving planes to the Logarithmic Laplacian ***,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at ***,the radial symmetry of th... 详细信息

关键词： the Logarithmic Laplacian system radial symmetry the direct method of moving planes

Heteroepitaxial growth of Au@Pd core–shell nanocrystals with intrinsic chiral surfaces for enantiomeric recognition

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Rare Metals 2024年第1期43卷 225-235页

作者： feng-Xia Wu feng-Hua Li Xia-Li Lv Qi-Xian zhang guo-Bao Xu Wen-Xin Niu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000China University of Science and Technology of China Hefei 230026China School of Materials Science and Engineering Shanghai UniversityShanghai 200436China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314113China University of Chinese Academy of Sciences Beijing 100039China

Noble metal surfaces with intrinsic chirality serve as an ideal candidate for investigating enantioselective chemistry due to their superior chemical durability and high catalytic ***,significant advance has been made in synthesizing metal nanocrystals with intrinsic ***,the majority reports are limited to ***,through a heteroepitaxial growth strategy,the synthesis of metal nanocrystals with intrinsic chirality to palladium was extended for the first time and their application in enantioselective recognition was *** heteroepitaxial growth strategy allows for transferring the chirality of homochiral Au nanocrystals to Au@Pd core–shell *** employing the chiral Au@Pd nanocrystals as enantiomeric recognizing elements,a series of electrochemical sensors for chiral discrimination were *** optimal conditions,the peak potential between D-dihydroxyphenylalanine(D-DOPA)and L-dihydroxyphenylalanine(L-DOPA)is about 80 m V,and the peak current of D-DOPA is 2 times as much as that of L-DOPA,which enables the determination of the enantiomeric excess(EE,%)of ***,this report not only introduces a heteroepitaxial growth strategy to synthesize metal nanocrystals with intrinsic chirality,but also demonstrates the superior capability of integrating intrinsic chirality and catalytic properties into metal nanocrystals for chiral recognition.

关键词： Core–shell nanostructures Chirality transfer Electrochemical sensors Chiral recognition Chiroplasmonics