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fluorescence.correlation spectroscopy in laser gradient field

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Chinese Science Bulletin 2001年第19期46卷 1589-1592页

作者： Fanbo Meng Bo Chen Yao Ding Hui Ma Lei Jin Dieyan Chen Tsing Hua Univ Dept Phys Mol & Nano Sci Lab Beijing 100084 Peoples R China

fluorescence.correlation spectroscopy (FCS) is capable of probing dynamic processes in living biological systems. From photon fluctuation of fluorescing particles which diffuse through a small detection volume, FCS reveals information on the concentration and the structure of the particles, as well as information on microscopic environment. In this note, we study the radiation forces experienced by Rayleigh particles in a laser field in details, and analyze the effects of gradient field on FCS measurements.

关键词： fluorescence correlation spectroscopy gradient field Brownian motion two-photon fluorescence.

THE CHARACTERISTIC fluorescence.OF THE SERUM OF CANCER PATIENTS

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Chinese Science Bulletin 1989年第2期34卷 166-170页

作者：孟继武侯尚公徐叙瑢马焕璞王德盛祖淑清房长茂 Changchun Institute of Physics Acadmia Sinica The People's Hospital of Jilin Province Changchun

Ⅰ. INTRODUCTIONThe purpose of this note is to find a correlation of cancer with patient’s serum fluorescence. This idea is based upon the fact that anomalous molecules in cancer cells may enter into human tissue and... 详细信息

关键词： cancer serum fluorescence.

PREPARATION AND CHARACTERIZATION OF SHISH-KEBAB TYPE LIQUID CRYSTALLINE POLY(p-PHENYLENEVINYLENE)

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Chinese Journal of Polymer Science 2006年第4期24卷 353-361页

作者： Kazuo Akagi 郑世军 Institute of Materials Science University of Tsukuba Tsukuba 305-8573Japan College of the Material Science and Engineering Zhengzhou University Zhengzhou 450052 China

Novel shish-kebab type liquid crystalline poly（p-phenylenevinylene） derivatives were synthesized by Stille coupling reaction from 2,5-bis[（4-n-alkoxyl）benzoyloxy]1,4-dibromobenzene （monomer l） and 1,2-bis（tributylstannyl） ethylene （monomer 2）. The polymers with alkoxy groups are soluble in common organic solvents and exhibit blue fluorescence. Both the cast film and the annealed film have large red-shifts in fluorescence.spectra and show yellow fluorescence. The polymers with CN and NO2 groups show poor solubility and green fluorescence. All the polymers possess liquid crystalline smectic phases. The melting point （Tm） of the polymers decreases when the length of the alkoxy tails of the mesogenic units increases. The polymers are easily aligned under a magnetic field of 10 Tesla. It is found that the conjugated backbone and LC side chain are aligned perpendicular and parallel to the magnetic field, respectively. The polymers show optical dichroism in fluorescence.spectra, suggesting that they are available for advance materials with linear optical polarization.

关键词： Liquid crystalline conjugated polymers Poly(p-phenylenevinylene) Shish-kebab Linearly polarized dichroism fluorescence.

Detennination of trace uranium in environment by laser induced fluorescence.method

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Journal of Environmental Sciences 1994年第1期6卷 93-98页

作者： Wu Jinhai, Yuan Zhengan, Li Jinquan, Zhang Chuanzuo, Ren Lihua(Institutc of Radiation Medicine Shanghai 200032, China)

he analytical technique of trace uranium has been developed rapidly since Robbins firstreported the laser uranium analyzer in 1978. Because of the complicated operation and experimentalprocedure of the normal spectrophotometer, neutron activation and solid fluorescence. they havebeen replaced gradually by the laser induced fluoresccncc mcthod. According to high sensitivity andIow detection limit of the fluoreseenee, it can determine the trace uranium. The uranium content inthe lake water, underground water and rain etc. can be measured directly without pretreatment. Therange of the method for determining uranium is from 005 ppb to 20 ppb, and the detection limitis 0.05 ppb.

关键词： laser analysis environmental uranium fluorescence.

SYNTHESIS OF CHIRAL CONJUGATED POLYBINAPHTHYLS BY SONOGASHIRA REACTION

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Chinese Journal of Polymer Science 2006年第3期24卷 273-279页

作者：成义祥 Ling-wu Chen Xiao-wei Zou Jin-feng Song College of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

Chiral polymers P-1 and P-2 were synthesized by the polymerization of （R）-3,3＇-diiodo-2,2＇-bisbutoxy-1,1＇- binaphthyl （M- 1 ） with 2,5-di（4-ethynylphenyl）- 1,3,4-oxadiazole （M-3） and （R）-3,3＇-diethylnyl-2,2＇-bisbutoxy- 1,1 ＇-binaphthyl （M-2） with 1,2-di（4-bromophenyl）acetylene （M-4） under Sonogashira reaction, respectively. Both monomers and polymers were analyzed by NMR, MS, FT-IR, UV-Vis spectroscopy, DSC-TGA, fluorescence.spectroscopy, GPC and CD spectroscopy. CD spectra of P-1 and P-2 are similar due to the same chiral center units and main chain structure. The long wavelengths CD effect of P-1 and P-2 can be regarded as the more extended conjugated structure and a highly rigid backbone in the polymer chain. Polymers have strong blue fluorescence.due to the efficient energy migration from the extended n-electronic structure of the polymers to the chiral binaphthyl core and are expected to provide understanding of the relationship between molecular structure and fluorescent property of the chiral polymers.

关键词： (R)-BINOL Chiral conjugated polymer Sonogashira reaction fluorescence.

SYNTHESIS OF CROSS-CONJUGATED(p-PHENYLENE)S-POLY(p-PHENYLENEVINYLENE)S HYBRIDS WITH LOW CONTENT OF STRUCTURAL DEFECTS

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Chinese Journal of Polymer Science 2007年第2期25卷 171-179页

作者： Shi-jun Zheng Qun Xu Shao-kui Cao College of the Material Science and Engineertng Zhengzhou University Zhengzhou 450052 China

The novel shish-kebab-type liquid crystalline cross-conjugated （p-phenylene）s-poly（p-phenylenevinylene）s hybrid was synthesized through Gilch polymerization. Their structures and properties were characterized by NMR, GPC, DSC, X-ray diffraction and polarizing optical microscope （POM）. ^1H-NMR investigation of the polymers indicates that the shish-kebab-structure has a strong ability to suppress the structural defects in the polymers. The polymers are enantiotropic liquid crystals. The melting point （Tm） of the polymers decreases when the length of the alkoxy tails of the mesogenic units increases. The mesophase was identified by X-ray diffraction method. They showed not only a smectic LC phase, but also a strong green fluorescence.in chloroform. The maximum absorption band of the ＂kebabs＂ of the two, 5-bis（4＇- alkoxyphenyl）benzene at 280 nm did not appear in absorption spectra of the polymers. The same phenomena were also observed in the fluorescence.spectra. These results imply that the polymers have formed a cross-conjugated uniform structure and achieved an extended n-conjugation polymer.

关键词： Gilch polymerization Conjugated polymer Liquid crystal Shish-kebab fluorescence.

Aggregation behavior of amphiphilic D-π-A molecules bearing recognition group

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Science China Chemistry 2000年第5期43卷 555-560页

作者：杨文胜姜月顺柴向东李铁津符连社张洪杰 Department of Chemistry Jilin University Changchun 130023 China Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Aggregation behavior of two amphiphilic D-π-A molecules bearing barbituric acid as both recogniton group and electron-drawing substituent , 5-(4-dodecyl oxybenzylidene)-(1H, 3H)-2,4,6-pyrimidine trione (PB12) and 5-(4-N,N-didodecyl aminobenzylidene)-(1H,3H)-2,4,6-pyrimidine trione (AB12) was studied by UV-visible, fluorescence. and surface voltaic spectroscopies (SPS). The experimental results indicate that PB12 tends to form J-aggregate and AB12 tends to form H-aggregate under increasing concentration. An intramolecular twisted charge transfer (TICT) emission around 500 nm is observed when J-aggregate is formed between PB12 molecules, and an excimer emission around 600 nm is observed when H-aggregate is formed between AB12 molecules.

关键词： D-π-A molecules molecular recognition J-aggregate H-aggregate fluorescence.

Study on Interaction of L-Tryptophan with p-Suffonatocalix[4]arene by Spectrofluorometry

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Chinese Chemical Letters 2006年第12期17卷 1592-1594页

作者： Wen Ye LI Ying Li WEI Wen Ting AN Shao Min SHUANG Man Shing WONG School of Chemistry and Chelmcal Engmeenng Shanxi University Taiyuan 030006 Department of Chemistry Hong Kong Baptist University Hong Kong

The interactions between L-tryptophan（L-Trp） and water-soluble p-sulfonatocalix[4]- arene （SCX4） were investigated by spectrofluorometry. The effect of pH was discussed. The interaction process was estimated from the thermodynamic viewpoint. The SCX4 was found to be able to adjust its conformation to fit the size of L-Trp, and the benzene of L-Trp penetrated into the hydrophobic cavity of SCX4. Meanwhile, the binding mechanism was further elucidated by IHNMR and molecular mechanics calculations.

关键词： L-Tryptophan p-sulfonatocalixarene fluorescence.

The Electron Transfer Reaction between ρ-Nitrobenzoates and β-N, N-Dimethylaminonaphthalene

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Chinese Chemical Letters 2003年第2期14卷 159-162页

作者： Yong Hui WANG Man Zhou ZHU Tao LIU Qing Xiang GUO Department of Chemistry University of Science and Technology of ChinaHefei 230026

A few of p-nitrobenzoates were synthesized, and the electron transfer of them with b-N, N-dimethylaminonaphthalene (DMAN) in methanol solution was studied. Steady-state fluore-scence results showed the cyclodextrin moiety in p-nitrobenzoyl-b-cyclodextrin would block the electron transfer pathway from DMAN compared with other electron acceptors, thus, reduced the electron transfer efficiency.

关键词： Electron transfer β-cyclodextrin naphthalene derivatives fluorescence.