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luminescence Studies on Interaction of an Isoquinoline Alkaloid with Calf Thymus DNA in Aqueous Medium and on Solid Substrate

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Chemical Research in Chinese Universities 2012年第4期28卷 614-619页

作者： LI Jun-fenl SHI Wen-tao HAN Xiu-ying DONG Chuan CHOI Martin M.F. School of Chemistry and Chemical Engineering Research Center of Environmental Science and Engineering Shanxi UniversityTaiyuan 030006P.R.China Department of Chemistry Hong Kong Baptist UniversityHong KongP.R.China

The interaction of calf thymus DNA（ctDNA） with berberine（Ber） was systematically investigated via UV-Vis,fluorescence and phosphorescence spectroscopies in aqueous solution and on solid *** very weak fluorescence intensity of Ber at 525 nm in aqueous solution can be greatly enhanced by *** UV-Vis spectrum shows that Ber could bind with DNA by *** addition,strong fluorescence of Ber alone could be observed on filter paper substrate and can be quenched by ctDNA effectively,and the increase of fluorescence polarization of Ber on the filter paper implies the intercalation *** emits phosphorescence at 619 nm in the presence of thallium（I） *** lifetime of Ber increased from 38.4 ms to 43.4 ms with the increase of *** increase of lifetime is possibly attributed to the increase of rigidity of Ber after its intercalating into the ctDNA base *** explanation is also augmented by the anionic quenching *** behaves as a typical intercalating agent into *** intrinsic binding constant between Ber and ctDNA is（1.84±0.12）×10^4 L/mol and n=0.16.

关键词： Berberine Calf thymus DNA UV-Vis spectroscopy luminescence Interaction

luminescence anti-counterfeiting:From elementary to advanced

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Aggregate 2021年第1期2卷 20-34页

作者： Xiaowei Yu Hongyue Zhang Jihong Yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchunP.R.China International Center of Future Science Jilin UniversityChangchunP.R.China

luminescence anti-counterfeiting derives from the easily changeable luminescence behaviors of luminescence materials under the regulation of various external stimuli(such as excitation light,chemical reagent,heat,and mechanical force,etc.)and luminescence lifetime,which plays an important role in preventing forgery of currency,artworks,and product *** to the numbers of changes of anti-counterfeiting labels under various regulation conditions,luminescence anti-counterfeiting can be classified into three levels from elementary to advanced:single-level anti-counterfeiting,double-level anti-counterfeiting,and multilevel *** this review,the recent achievements in luminescence anti-counterfeiting are summarized,and the regulation of various factors to anti-counterfeiting labels is ***,existing problems,future challenges,and possible development directions are proposed in order to realize facile,quick,low-cost,environmentally friendly,and difficult-to-replicate advanced luminescence anti-counterfeiting.

关键词： anti-counterfeiting down conversion external stimuli lifetime luminescence up conversion

luminescence enhancement from Si-based materials by introducing a photonic crystal double-heterostructure slot waveguide microcavity

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Optoelectronics Letters 2011年第4期7卷 266-268页

作者：王玥吴远大张家顺安俊明胡雄伟 Optoelectronics Research and Development Center Institute of SemiconductorsChinese Academy of Sciences Optoelectronics Research and Development Center Institute of Semi conductorsChinese Academy of Sciences

We demonstrate a novel SOI-based photonic crystal（PC） double-heterostructure slot waveguide microcavity constructed by cascading three PC slot waveguides with different slot widths,and simulate the luminescence enhancement of sol-gel Er-doped SiO2 filled in the microcavity by finite-difference time-domain（FDTD） *** calculated results indicate that a unique sharp resonant peak dominates in the spectrum at the expected telecommunication wavelength of 1.5509 mm,with very high normalized peak intensity of ~*** electromagnetic field of the resonant mode exhibits the strongest in the microcavity,and decays rapidly to zero along both sides,which means that the resonant mode field is well confined in the *** simulation results fully verify the enhancement of luminescence by PC double-heterostructure slot waveguide microcavity theoretically,which is a promising way to realize the high-efficiency luminescence of Si-based materials.

关键词： Electromagnetic fields Finite difference time domain method luminescence Photonic crystals Silicon compounds Time domain analysis Waveguides

luminescence of Nanosized Supramolecular Material of Mesoporous Molecular Sieve and Samarium (Ⅲ) Complex

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Chemical Research in Chinese Universities 2003年第4期19卷 504-507页

作者： YIN Wei ZHANG Mai-sheng School of Chemistry and Chemical Engineering Sun Yat-sen(Zhongshan)UniversityGuangzhou 510275P.R.China

The solutions of rare earth complexes Sm(Phen) 2(TTA)(Bipy)(NO 3) 3 and Sm(L) x (TTA) 4-x (NO 3) 3 [L=Phen (1,10-phenanthroline) or Bipy(2,2′-bipyridine), x =4, 3, 2, 1, 0; TTA is 2-thenoyltrifluoacetone] in EtOH(1×10 -3 mol/L) were prepared. The coefficients of antenna effect are 31 5, 18 2 and 5 6 for Phen, Bipy and TTA, respectively, when the electron configuration of the excited state of the samarium atom in the complexes is 4 D 1/2 . The fluorescent intensity and the lifetime of the supramolecular encapsulation products of (CH 3) 3Si-MCM-41 and Sm 3+ complexes are stronger and longer than those of the encapsulation products of MCM-41 and Sm 3+ complexes respectively. The results show that the host with lipophilic channels is more favourable to the fluorescence of the rare earth complexes than the hydrophilic mesoporous molecular sieve. The fluorescent intensity of (CH 3) 3Si-MCM-41-Sm(Phen) 3(TTA)(NO 3) 3 is the strongest \{among\} the encapsulation series of Sm 3+ complexes, which is assumed to result from the greatly reduction of SiO-H vibration relaxation in host (CH 3) 3Si-MCM-41 and the presence of the discrete strong luminescent centres of the guest molecules associated with the nanosized material′s structure. The luminescent decay halftime of the supramolecular materials is much shorter than that of the powder of the samarium complexes. The result shows that the ligand transferring energy from the triplet state to the singlet state of Sm 3+ ( T 1→S , intersystem crossing) becomes higher. The fluorescent experimental results indicate that the interaction between the host and the guest influences the luminescent properties of the nanostructured supramolecular materials.

关键词： MCM-41(CH _(3)) _(3)Si-MCM-41 Supramolecular system luminescence Exponential decay

Size Effects on the luminescence Properties of Polymer Nanowires

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Chinese Journal of Polymer Science 2014年第2期32卷 130-136页

作者：孙秀玉 Xiang-lan Liu Fa-qiang Xu Li Xue Ying-zhi Cheng School of Chemical Engineering Shandong University of Technology Key Laboratory of Material Physics Institute of Solid State Physics Chinese Academy of Sciences National Synchrotron Radiation Laboratory University of Science and Technology of China

Poly（3-（2-methoxyphenyl）thiophene）（PMP-Th） nanowires were fabricated using porous anodic alumina （PAA） as template through electrochemical polymerization by cyclic voltammetry. The control on the size of nanowires was confirmed by electron microscopy. The results indicated that the luminescence spectra of PMP-Th nanowires in PAA nanochannels were blue-shifted and emission intensity was enhanced compared to the emission of the PMP-Th film. Moreover, the luminescent spectra of PMP-Th nanowires were size dependent, which may result from the change in the degree of confinement of nanowires in PAA. F6rster energy transfer from PAA to PMP-Th molecules is considered to be responsible for the enhancement of luminescence from PMP-Th nanowires in PAA. The results show that the emission properties of polymers with nanostructures can be tuned by controlling their size.

关键词： Polythiophene Nanowires luminescence Blue-shift.

(Zn,Ca) Solid-Solution Behavior and Its Effect on luminescence Properties in Ca_(1-x)Zn_xTiO_3∶0.002Pr^(3+) Phosphors

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Journal of Rare Earths 2005年第6期23卷 662-667页

作者：洪樟连张朋越王民权 Department of Material Science and Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory of Silicon Materials Zhejiang University Hangzhou 310027 China Department

Nominal composition of Ca1-xZnxTiO3 ： 0. 002Pr^3 ＋（x = 0. 000 - 0. 200） phosphors were prepared by conventional solid reaction route. XRD and PL measurements were used to investigate the solid-solution structure and luminescence properties of Zn-doped Ca1-xZnxTiO3：0.002Pr^3＋ phosphors. The effect of solid-solution structure formed by substitution between Ca^2 ＋ and Zn^2＋ ions on the luminescent properties was analyzed. The results reveal that, with the increase of Zn substitution content below 0.010, lattice parameters and the intensity of excitation peak at both 260 and 330 nm as well as the corresponding 610 nm emission intensity are monotonously decreased quickly in a similar tendency. Also, the evolution of luminescence intensity and crystal cell parameters against Zn doping concentration are in good agreement. Above results are closely related with the structure change within Ca1- xZnxTiO3：0.002Pr^3＋ solid-solution phase formed by the Zn ions substitution for the Ca sites. Present study reveals that the solid-solution structure formed by substitution between Ca^2＋ and Zn^2＋ ions has significant effect on the luminescence properties of single phase Ca1-xZnxTiO3：0.002Pr^3＋ phosphors.

关键词： Ca1-xZnxTiO3 : Pr3+ solid solution luminescence perovskite structure rare earths

Stepwise Crystalline Structural Transformation in 0D Hybrid Antimony Halides with Triplet Turn-on and Color-Adjustable luminescence Switching

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Research 2023年第4期2023卷 485-497页

作者： Jian-Qiang Zhao Yue-Yu Ma Xue-Jie Zhao Yu-Jia Gao Zi-Yan Xu Pan-Chao Xiao Cheng-Yang Yue Xiao-Wu Lei School of Chemistry Chemical Engineer and MaterialsJining UniversityQufuShandong 273155P.R.China

Intelligent stimuli-responsive fluorescence materials are extremely pivotal for fabricating luminescent turn-on switching in solid-state photonic integration technology,but it remains a challenging objective for typical 3-dimensional(3D)perovskite ***,by fine-tuning the accumulation modes of metal halide components to dynamically control the carrier characteristics,a novel triple-mode photoluminescence(PL)switching was realized in 0D metal halide through stepwise single-crystal to single-crystal(SC-SC)***,a family of 0D hybrid antimony halides was designed to exhibit three distinct types of PL performance including nonluminescent[Ph_(3)EtP]_(2)Sb_(2)Cl_(8)(1),yellowemissive[Ph3EtP]2SbCl5·EtOH(2),and red-emissive[Ph_(3)EtP]_(2)SbCl_(5)(3).Upon stimulus of ethanol,1 was successfully converted to 2 through SC-SC transformation with enhanced PL quantum yield from~0%to 91.50%acting as“turn-on”luminescent ***,reversible SC-SC and luminescence transformation between 2 and 3 can be also achieved in the ethanol impregnation-heating process as luminescence vapochromism *** a consequence,a new triple-model turn-on and coloradjustable luminescent switching of off-onI-onII was realized in 0D hybrid ***,wide advanced applications were also achieved in anti-counterfeiting,information security,and optical logic *** novel photon engineering strategy is expected to deepen the understanding of dynamic PL switching mechanism and guide development of new smart luminescence materials in cutting-edge optical switchable device.

关键词： luminescence halide Transformation

Optical,thermal and luminescence properties of La2O3-Ga2O3-ZrO2 glasses co-doped with Tm3+/Yb3+prepared by containerless technique

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Journal of Rare Earths 2022年第11期40卷 1706-1714,I0002页

作者： Jiansheng Xie Minghui Zhang Yanzhuo Wang Rongting Guo Ying Shi Xiuhong Pan Xuechao Liu Kun Chen Meibo Tang Feng Wu Zhihong Zhang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Wuhan Institute of TechnologyWuhan 430205China College of Chemical and Biological Engineering Guilin University of TechnologyGuangxi Key Laboratory of Electrochemical and Magneto-chemical Functional MaterialsGuilin 541004China AECC-Chengdu Chengdu 610500China

Bulk LaO-GaO-ZrO(LGZ)glass and Tm/Ybco-doped LGZ glasses were synthesized successfully using containerless *** spectra result reveals that the matrix sample possesses the low maximum phonon energy of~642 *** glasses show good compatibility between large Abbe numbers(>31)and high refractive indices(n>1.93).Moreover,transmittance measurements reflect that the glasses have high infrared transmittance of-81.9%,small OHabsorption coefficient and long mid-infrared cut-off wavelengths(-7.5μm).The surface morphology of host glass was characterized by scanning electron microscopy(SEM)micrograph and energy dispersive spectroscopy(EDS)tests reflect that the doped compositions are distributed into the matrix glass *** results of thermal analysis show that the glasses have good thermal properties(T>769℃).Excited by 980 am laser,an intense 1810 am fluorescence is obtained originating from the transition:~3 E→~3 Hof Tmion,accompanied by upconversion *** can be observed that 1810 nm fluorescence has the highest intensity at 1 mol%YbOand owns broad full width at half-maximum(>245 nm),the luminescence intensity of~3 F→~3 Htransition increases with rising temperature from 300 to 550 ***,the value of energy transfer efficiency shows that Ybcan transfer energy to *** fitting the attenuation curves,the lifetimes of 1810 and 474 nm emission can be acquired.

关键词： Containerless technique Lanthanum gallate glass Thermal analysis luminescence Rare earth ions

Structure and luminescence of Ca_2Si_5N_8:Eu^(2+) phosphor for warm white light-emitting diodes

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Chinese Physics B 2009年第8期18卷 3555-3562页

作者：魏小丹蔡丽艳鲁法春陈小龙陈学元刘泉林 School of Materials Science & Engineering and State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

We have synthesized Ca2Si5N8：Eu^2＋ phosphor through a solid-state reaction and investigated its structural and luminescent properties. Our Rietveld refinement of the crystal structure of Ca1.9Eu0.1Si5N8 reveals that Eu atoms substituting for Ca atoms occupy two crystallographic positions. Between 10 K and 300 K, Ca2Si5N8：Eu^2＋ phosphor shows a broad red emission band centred at -1.97 eV-2.01 eV. The gravity centre of the excitation band is located at 3.0 eV 3.31 eV. The centroid shift of the 5d levels of Eu^2＋ is determined to be -1.17 eV, and the red-shift of the lowest absorption band to be - 0.54 eV due to the crystal field splitting. We have analysed the temperature dependence of PL by using a configuration coordinate model. The Huang-Rhys parameter S = 6.0, the phonon energy hv = 52 meV, and the Stokes shift △S = 0.57 eV are obtained. The emission intensity maximum occurring at -200 K can be explained by a trapping effect. Both photoluminescence （PL） emission intensity and decay time decrease with temperature increasing beyond 200 K due to the non-radiative process.

关键词： luminescence structure nitride europium white light-emitting diode (LED)