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THE PHOTOPOLYMERIZATION KINETICS OF PHOTOSENSITIZED ACRYLAMIDE SYSTEM INDUCED BY He-Ne LASER

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Chinese Journal of Polymer Science 1991年第1期9卷 24-30页

作者：冯敏辉梁兆熙陈用烈 Institute of Polymer Science Zhongshan University

The kinetics of the photopolymerization of sensitized acrylamide (AM) system induced by He-Ne laser has been investigated. Using methylene blue (MB)-triethanolamine (TEOA) as the photosensitive system, the photopolymerization followed a nonsteady-state kinetic scheme in the initial period of polymerization (the monomer conversion C%C%>2%). Accirding to the steady-state hypothesis, the mechanism of photopolymerization was proposed. The deduced kinetic equation of the photopolymerization of AM is in good coincidence with the experimental results.

关键词： He-Ne Laser Photopolymerization Photosensitive system quantum yield

Quantitative assessment of rhodamine spectra

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Chinese Chemical Letters 2021年第2期32卷 943-946页

作者： Wei Zhou Xiangning Fang Qinglong Qiao Wenchao Jiang Yue Zhang Zhaochao Xu CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical Physics.Chinese Academy of SciencesDalian 116023China Zhang Dayu School of Chemistry Dalian University of TechnologyDalian U6012China

With the development of single-molecule detection and super-resolution fluorescence imaging,rhodamine dyes gain new *** the modification of the N-substituents a nd the replacement of the oxygen atom in xanthene,the wavelength and brightness can be effectively ***,the spectra of rhodamine,especially due to the balance between ring-closed non-fluorescent lactone and ring-opened fluorescent zwitterion/cation,are sensitive to interference from various environmental facto rs,In this way,the spectral data of various rhodamines repo rted by different re search groups under different test conditions lacked comparability,sometimes even lacked *** order to meet the requirements for the accuracy and uniformity of spectral data in the research of single molecule imaging and dye structure-fluorescence relationship study,we have tested the spectra of fifteen rhodamine dyes that cover the visible and near-infrared regions under exactly the same *** studying the dependence of the spectra on dye concentrations,it was confirmed that 1 μmol/L was ideal fo r detection less from the interference of dye molecule *** provide compre hensive and reliable spectral data of these fifteen dyes,which are expected to be used as references for future *** the direct comparison of different rhodamine spectra would help to understand the structure-fluorescence relationship of rhodamines.

关键词： Rhodamine Quantitative assessment Absorption Emission quantum yield

Photosynthetic activity and antioxidative response of seagrass Thalassia hemprichii to trace metal stress

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Acta Oceanologica Sinica 2012年第3期31卷 98-108页

作者： LI Lei HUANG Xiaoping Devajit Borthakur NI Hui State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Graduate University of Chinese Academy of Sciences Beijing 100049China Tropical Marine Biological Research Station in Hainan Chinese Academy of SciencesSanya 572200China The Science and Technology Library of Guangdong Province Guangzhou 510070China Tocklai Experimental Station Tea Research AssociationJorhatAssam 785008India Foreign Language Department Heze UniversityHeze 274000China

This study concerned the accumulation of trace metals in tissues of seagrass ( Thalassia hemprichii) exposed to various concentrations of Zn2+,Cd2+,Pb2+ and Cu2+ for 10 d,and the effect of excessive metals on quantum yield (△F/F′m),photosynthetic pigments and antioxidative enzymes like superoxide dismutase (SOD),guaiacol peroxidase (POD) were also *** was the most highly accumulated ***,high metals levels led to a remarkable breakdown of photosynthetic ***,△F/F′m,chlorophyll and carotenoid were significantly low during prolonged Cu ***,△F/F′m was more severely depressed by Cu and Zn than Pb and ***,*** had positive response by increasing the activity of SOD and *** results indicate that *** is the most sensitive to Cu,and the antioxidative protection mechanisms of *** are more efficiently activated to avoid damage of Zn,Cd and Pb stress. Finally,due to the high Cd-accumulation and strong Cd-tolerance capacity,*** can be used for phytoremediation in Cd-contaminated areas.

关键词： Thalassia hemprichii metal stress photosynthetic pigments quantum yield antioxidant enzymes

Ultrafast Excited State Dynamics of Biliverdin Dimethyl Ester Coordinate with Zinc Ions

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Chinese Journal of Chemical Physics 2020年第1期33卷 69-74,I0030-I0033页

作者： Zhuang Chen Yang-yi Liu Xiao-xiao He Jin-quan Chen State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

As one of the biological endogenous pigments,biliverdin(BV)and its dimethyl ester(BVE)have extremely weak uorescence in solution with quantum yield less than 0.01%.However,the situation reverses with the addition of zinc *** strength for uorescence of BVE-Zn^2+ complex is greatly enhanced and uorescence quantum yield can increase to5%.Herein,we studied ultrafast excited state dynamics of BVE-Zn^2+ complex in ethanol,npropanol,and DMSO solutions in order to reveal the mechanism of uorescence quantum yield *** results show that BVE can form a stable coordination complex with zinc with 1:1 stoichiometry in *** is structurally and energetically more stable in the *** picosecond time-resolve uorescence and femtosecond transient absorption spectroscopy,we show that smaller non-radiative rate constant of BVE-Zn^2+ complex in DMSO is the key to increasing its uorescence quantum yield and the excited state decay mechanism is also *** results provide valuable information about the uorescence property change after BVE binding to metal ions and may provide a guidance for the study of phytochromes or other uorescence proteins in which BV/BVE acts as chromophores.

关键词： Biliverdin Zinc Fluorescence quantum yield Femtosecond transient absorption Excited state dynamics

Low Temperature Epitaxial Growth of Semiconductors Using Synchrotron Radiation as a Light Source

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材料科学与工程学报 2000年第Z2期20卷 811-816页

作者： Qixin GUO Department of Electrical and Electronic Engineering Faculty of Science and EngineeringSaga University Saga 840-8502 Japan

Results of our recent experiments relating to the synchrotron radiation (SR) excited growth of Ⅱ-V compounds using metalorganic sources are described. We discuss mainly the growth characteristics of films in addition to the characterization of the deposited films. ZnTe epitaxial layer without carbon and oxygen contamination is attainable even at room temperature using SR as a light source. The quantum yield for forming ZnTe molecules was estimated to be higher than 3%. Through these experiments, we propose that the SR-excited growth is a powerful technique for a novel low temperature growth of compounds.

关键词： Light Source Synchrotron Radiation growth characteristics synchrotron radiation room temperature low temperature quantum yield light source

Syntheses, Structures and Luminescent Properties of Eu-and Tb-MOFs with 3,5-Pyridinedicarboxylate and 1,2-Benzenedicarboxylate

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Syntheses, Structures and Luminescent Properties of Eu-and T...

河南省化学会2020年学术年会

作者：王世超朱孟斌王军萍杨凡刘瞻梁彩莲李会王宏胜许昌学院化工与材料学院

Two lanthanide-based MOFs (Ln-MOFs) were synthesized by reaction of Eu(III) or Tb(III)perchlorates with two dicarboxylates of 3,5-pdc and 1,2-bdc (3,5-Hpdc=3,5-pyridinedicarboxylic acid;1,2-Hbdc=1,2-benzenedicarboxylic acid) by hydrothermal *** chemical formulas of the two complexes were[Eu(3,5-pdc)(1,2-bdc)(HO)] (1)and{[Tb(3,5-pdc)(1,2-bdc) (HO)]·2HO} (2).IR spectra and element analyses were tested to characterize the two *** crystal structures were determined by X-ray single crystal *** 1 was 3D porous network structure but MOF 2 was 2D layered *** two MOFs both emitted the characteristic fluorescence of Eu(III) or Tb(III) ion with the excitations of *** lifetimes of excited states for Eu(III)(D) and Tb(III)(D) were0.31 and 0.82 *** absolute quantum yields (Ф) of MOF 1 and 2 were also tested and theФ(1)(λ=320 nm) andФ (2)(λ=296 nm) were 15%and 48%,respectively.

关键词： Photoluminescence quantum yield fluorescence lifetime

Plasmon Hot Electron Injection Induces Singlet Oxygen Generation by Au/MoS2 Hybrid with Enhanced In Vivo Photodynamic Therapy

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Plasmon Hot Electron Injection Induces Singlet Oxygen Genera...

中国化学会第十三届全国分析化学年会

作者： Muhammad Rizwan Younis Chen Wang Qian Wen Zhang Ruibing An De-Ju Ye Xing-Hua Xia State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering Nanjing University Department of Physical Chemistry School of Science China Pharmaceutical University

Recently,plasmonic metal/semiconductor hybrid nanostructures (NSs) have emerged as a potential nano-photosensitizers (NPSs) to generate reactive oxygen species (ROSs)especially singlet oxygen (O) via type I ***,their practical clinical applications are limited due to low O generation quantum ***,we develop plasmonic Au/MoS hybrid based NPS for the first time and demonstrate indepth investigation of O generation ***,Au/MoS hybrid were prepared by electrostatic interaction and characterize by DLS,TEM and ***,O generation was confirmed by different O indicators especially O phosphorescent signal at 1270 nm,indicating a high O quantum yield compared to previously reported hybrid NPSs and thus shows excellent therapeutic performance both in vitro and in *** last,O generation mechanism studies confirm that Au/MoS undergo type 1 pathway to generate *** conclusion,our study will pave the way for the development of other hybrid NPSs with high O quantum yield with enhanced photodynamic therapy.

关键词： Nano-photosensitizer singlet oxygen quantum yield photodynamic therapy

The interchange between hybrid Mn(Ⅱ) chloride perovskite single crystals

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The interchange between hybrid Mn(Ⅱ) chloride perovskite si...

第三届新型太阳能电池学术研讨会

作者： Dianxing Ju Yangyang Dang Xutang Tao State Key Laboratory of Crystal Materials Shandong University Key Laboratory of Functional Crystal Materials and Device (Shandong University Ministry of Education)

Organic-inorganic hybrid single crystals demonstrate special challenges and opportunities with respect to potential applications in many optoelectronic fields,as well as for the observation of interesting physical ***,two kinds of hybrid Mn(Ⅱ) chloride perovskite single crystals were grown by slow evaporation method from different aqueous and hydrochloric acid solution with stoichiometric mixture of N(CH)Cl and MnCl·4HO at room *** crystal structures exhibit the orthorhombic(CH)NMnCl with space group Pnma and hexagonal(CH)NMnCl with space group P63/m by X-ray single-crystal diffraction analysis,respectively,as is shown in Figure ***,(CH)NMnCl and(CH)NMnCl are reversible via different condition in ambient ***,both single-crystals display intense green and red luminescence with quantum yield of 86.11% and 87.59% under UV wavelength excitation,which is ascribed to the different coordination environment of Mn.

关键词： hybrid Mn(Ⅱ) chloride perovskite single crystal quantum yield

O(3P0,1,2,1D2) yield ratio measurement in VUV photodissociation of O2

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O(3P0,1,2,1D2) yield ratio measurement in VUV photodissociat...

第十五届全国化学动力学会议

作者：刘凯 Yih Chung Chang Konstantinos S.Kalogerakis Tom G.Slanger Bing Zhang William M.Jackson Cheuk Yiu Ng Department of Chemistry University of California State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of Sciences Physical Sciences Division SRI International

The quantum yield of a VUV-induced photodissociation is defined as the ratio of the number of dissociative fragment created to the number of photons absorbed. Neutral photodissociation cross sections often remain significant for several electron volts above the ionization threshold and may be composed of contributions from both direct and indirect processes. We developed a method to measure the yield ratios of O atoms in different spin-orbital state, using VUV-VUV pump-probe lasers and the time-sliced velocity-map-imaging photoion(VMI-PI) method. Combining the quantum dissociation cross section data[1], we calculated the quantum yield for O P, P, P, D and S in VUV photodissociation of O(HП, v’=2) is 0.24(2), 0.31(2), 0.26(2), 0.38(2), 0, respectively.

关键词： superexcited oxygen quantum yield VUV photodissociation