Light conversion agents Eul-xLx（TTA）3Phen (L denotes (La3+, Gd3+, Y3+)) complexes were prepared, and the influence of doping ions on fluorescence properties was investigated by elementary analysis, FTIR and fluoresc...Light conversion agents Eul-xLx（TTA）3Phen (L denotes (La3+, Gd3+, Y3+)) complexes were prepared, and the influence of doping ions on fluorescence properties was investigated by elementary analysis, FTIR and fluorescent spectra. The results show that FTIR spectra of Eul-xLx（TTA）3Phen complex system are identical with that of EuTTA3Phen, which indicates that the complexes (Eul-xLx（TTA）3Phen) are similar in structure to （Eu （TTA）3Phen.） For the above doping elements, co-fluorescence enhancement has the following order: Gd3+>Y3+>La3+, and the optimum mole fractions of doping elements are 0.4, 0.2 and 0.5 respectively for Gd3+, Y3+, La3+. Among all the complexes, Eu0.6Gd0.4（TTA）3Phen complex has the strongest fluorescent intensity. Applying Eu0.6Gd0.4（TTA）3Phen complex to plastic and printing inks, bright red fluorescence plastic and printing inks are obtained when the content of europium reaches 0.1%（mass fraction）.展开更多
Energy transfers in two kinds of peripheral light-harvesting complexes （LH2） of Rhodobacter sphaeroides （RS） 601 are studied by using femtosecond pump^probe spectroscopy with tunable laser wavelength at room tempe...Energy transfers in two kinds of peripheral light-harvesting complexes （LH2） of Rhodobacter sphaeroides （RS） 601 are studied by using femtosecond pump^probe spectroscopy with tunable laser wavelength at room temperature. These two complexes are native LH2 （RS601） and green carotenoid mutated LH2 （GM309）. The obtained results demonstrate that, compared with spheroidenes with ten conjugated double bonds in native RS601, carotenoid in GM309 containing neurosporenes with nine conjugated double bonds can lead to a reduction in energy transfer rate in the B800-to-B850 band and the disturbance in the energy relaxation processes within the excitonic B850 band.展开更多
We present a digital micromirror device（DMD） based superpixel method for focusing light through scattering media by modulating the complex field of incident light. Firstly, we numerically and experimentally investig...We present a digital micromirror device（DMD） based superpixel method for focusing light through scattering media by modulating the complex field of incident light. Firstly, we numerically and experimentally investigate focusing light through a scattering sample using the superpixel methods with different target complex fields.Then, single-point and multiple-point focusing experiments are performed using this superpixel-based complex modulation method. In our experiment, up to 71.5% relative enhancement is realized. The use of the DMDbased superpixel method for the control of the complex field of incident light opens an avenue to improve the enhancement of focusing light through scattering media.展开更多
Energy transfer processes between two aggregates in a coupled chromophoric-pigment （protein） system are studied via the standard master equation approach. Each pigment of the two aggregates is modeled as a two-level...Energy transfer processes between two aggregates in a coupled chromophoric-pigment （protein） system are studied via the standard master equation approach. Each pigment of the two aggregates is modeled as a two-level system. The excitation energy is assumed to be transferred from the donor aggregate to the acceptor aggregate. The model can be used to theoretically simulate many aspects of light-harvesting complexes （LHCs）. By applying the real bio-parameters of photosynthesis, we numerically investigate the efficiency of energy transfer （EET） between the two aggregates in terms of some factors, e.g., the initial coherence of the donor aggregate, the coupling strengthes between the two aggregates and between different pigments, and the effects of noise from the environment. Our results provide evidence for that the actual numbers of pigments in the chromophoric tings of LHCs should be the optimum parameters for a high EET. We also give a detailed analysis of the effects of noise on the EET.展开更多
Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes （OLEDs） were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red an...Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes （OLEDs） were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red and white-phosphorescent OLEDs based on Pt complexes are presented in terms of efficiency and color quality.展开更多
Lanthanum and nitrogen co-doped SrTiO3 was synthesized using polymerized complex method with Ti(OC3H7)4, SrCl2·6H2O and La(NO3)3·6H2O as starting materials followed by calcinations in NH3. Ethylene glycol an...Lanthanum and nitrogen co-doped SrTiO3 was synthesized using polymerized complex method with Ti(OC3H7)4, SrCl2·6H2O and La(NO3)3·6H2O as starting materials followed by calcinations in NH3. Ethylene glycol and anhydrous citric acid were used as the precursors of synthesis. The samples were characterized using XRD, TEM, DRS, BET, EDX and XPS. The cubic-perovskite type of La/N co-doped SrTiO3 nanoparticle could be successfully synthesized. The photocatalytic activity of SrTiO3 for DeNOx ability in visible light region (λ > 510 nm) could be improved by co-doping of La3+ and N3_. The high visible light photocatalytic activity of this substance was caused by a narrow band gap energy that enables to absorb visible light.展开更多
Compounds with visible-light-induced photoluminescence are particularly attractive in acting as the emitting components of light-emitting diodes and fluorescent probes for biological applications. A new complex [Zn(NC...Compounds with visible-light-induced photoluminescence are particularly attractive in acting as the emitting components of light-emitting diodes and fluorescent probes for biological applications. A new complex [Zn(NCS)_3(MQ)](MQ^+ = N-methyl-4,4?-bipyridinium) with an isolated molecular structure has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and solid-state photoluminescent determination. Crystal data: C_(14)H_(11)N_5S_3Zn, M_r = 410.83, monoclinic, space group P2_1/c, a = 8.809(5), b = 13.138(7), c = 15.580(9) ?, b = 104.433(10)°, V = 1746.2(17) ?~3, Z = 4, D–c = 1.563 g×cm^3, μ = 1.769 mm^(–1), F(000) = 832, the final R = 0.0376 and wR = 0.1243 for 2850 observed reflections with I > 2s(I). In the crystal structure, the zinc atom is tetrahedrally coordinated by one MQ+ ligand and three NCS– groups to yield a tetrahedral configuration. The bond length of Zn–NMQ is clearly shorter than those found in reported Zn(Ⅱ) complexes of 4,4?-bipy. The isolated units are joined by C–H···S interactions to generate a 2D hydrogen-bonding network. This compound displays visible light-induced photoluminescence, which originates from both intraligand charge-transfer of the MQ+ ligand and NCS~–→MQ^+ charge-transfer according to a density of states(DOS) calculation. Moreover, its emission band shows a clear blue shift compared with those of halide compounds.展开更多
Recently,much attention has been paid to the lanthanide luminescent materials based on the visiblelight sensitization for their potential applications in the fields of bio-imaging and optical devices.In this work,the ...Recently,much attention has been paid to the lanthanide luminescent materials based on the visiblelight sensitization for their potential applications in the fields of bio-imaging and optical devices.In this work,the lanthanide complexes have been covalently bonded to the ordered mesoporous titania（OMT） matrix,and the resulting titania-based hybrid ordered mesoporous materials（named as LnDBOMT,Ln = Eu,Sm,Yb,Nd） were characterized by using Fourier-transform infrared（FT-IR） spectroscopy,small-angle X-ray powder diffraction（SAXD）,N2 adsorption-desorption isotherms,transmission electron microscopy（TEM）,fluorescence spectroscopy,and thermogravimetric analysis.Generally,exciting with visible light is advantageous over UV excitation.Of importance here is that,under excitation with visible light,the LnDB-OMT all show characteristic visible（Eu3＋,Sm3＋） as well as nearinfrared（Sm3＋,Yb3＋,Nd3＋） luminescence of the corresponding Ln3＋ ions（multicolor emission covered from 500 to 1400 nm spectral region）,which is attributed to the energy transfer from the ligands to the Ln3＋ ions via an antenna effect.展开更多
A series of isostructural d/f molecular compounds Zn（H2L）Ln（NO3）3·CH3OH（Ln = Dy（1）, Tb（2） and Sm（3）） were synthesized by the introduction of a designed multifunctional ligand N,N？,N？？,N？？？-tetra...A series of isostructural d/f molecular compounds Zn（H2L）Ln（NO3）3·CH3OH（Ln = Dy（1）, Tb（2） and Sm（3）） were synthesized by the introduction of a designed multifunctional ligand N,N？,N？？,N？？？-tetra（2-hydroxy-3-methoxy-5-methylbenzyl）-1,4,7,10-tetraazacyclododecan（H4L = C（44）H（60）N4O8）. In the isostructural molecules, each crystallographically independent Zn2＋ and Ln3＋ centers are connected by two phenolic oxygen atoms. For the six-coordinate Zn-（2＋） ion, the coordination geometry can be viewed as a regular bicapped square pyramid. While for the ten-coordinate Ln-（3＋） ion, if each O,O？-chelated nitrate ligand is seen as a single coordination site, the coordination geometry can be viewed as a distorted pentagonal bipyramid. The fluorescent spectra show that compounds 2 and 3 exhibited characteristic sharp emissions of Tb-（3＋） and Sm-（3＋）, respectively, while compound 1 was found to be a single-component white-light-emitting complex in the solid state. Thermal stabilities of the three compounds were investigated by using thermal gravimetric analysis. In addition, the thermal decomposition of compound 1 was confirmed by temperature-dependent powder X-ray diffraction technique.展开更多
文摘Light conversion agents Eul-xLx（TTA）3Phen (L denotes (La3+, Gd3+, Y3+)) complexes were prepared, and the influence of doping ions on fluorescence properties was investigated by elementary analysis, FTIR and fluorescent spectra. The results show that FTIR spectra of Eul-xLx（TTA）3Phen complex system are identical with that of EuTTA3Phen, which indicates that the complexes (Eul-xLx（TTA）3Phen) are similar in structure to （Eu （TTA）3Phen.） For the above doping elements, co-fluorescence enhancement has the following order: Gd3+>Y3+>La3+, and the optimum mole fractions of doping elements are 0.4, 0.2 and 0.5 respectively for Gd3+, Y3+, La3+. Among all the complexes, Eu0.6Gd0.4（TTA）3Phen complex has the strongest fluorescent intensity. Applying Eu0.6Gd0.4（TTA）3Phen complex to plastic and printing inks, bright red fluorescence plastic and printing inks are obtained when the content of europium reaches 0.1%（mass fraction）.
基金Project supported by the National Natural Science Foundation of China （Grant No 10274013）.
文摘Energy transfers in two kinds of peripheral light-harvesting complexes （LH2） of Rhodobacter sphaeroides （RS） 601 are studied by using femtosecond pump^probe spectroscopy with tunable laser wavelength at room temperature. These two complexes are native LH2 （RS601） and green carotenoid mutated LH2 （GM309）. The obtained results demonstrate that, compared with spheroidenes with ten conjugated double bonds in native RS601, carotenoid in GM309 containing neurosporenes with nine conjugated double bonds can lead to a reduction in energy transfer rate in the B800-to-B850 band and the disturbance in the energy relaxation processes within the excitonic B850 band.
基金the National Natural Science Foundation of China，the National Basic Research Program，the Strategic Priority Research Program of Chinese Academy of Sciences
基金Supported by the Natural Science Foundation of Beijing under Grant Nos 2162033 and 7182091the National Natural Science Foundation of China under Grant No 21627813
文摘We present a digital micromirror device（DMD） based superpixel method for focusing light through scattering media by modulating the complex field of incident light. Firstly, we numerically and experimentally investigate focusing light through a scattering sample using the superpixel methods with different target complex fields.Then, single-point and multiple-point focusing experiments are performed using this superpixel-based complex modulation method. In our experiment, up to 71.5% relative enhancement is realized. The use of the DMDbased superpixel method for the control of the complex field of incident light opens an avenue to improve the enhancement of focusing light through scattering media.
基金Financial supports from the Natural Science Foundation of Shandong Province(Y2000B09)Shandong Provincial Science and Technology Program(03C05)are gratefully acknowledged
基金Project supported by the National Natural Science Foundation of China(Grant No.11174233)the National Basic Research Program of China(Grant No.2011CB311807)
文摘Energy transfer processes between two aggregates in a coupled chromophoric-pigment （protein） system are studied via the standard master equation approach. Each pigment of the two aggregates is modeled as a two-level system. The excitation energy is assumed to be transferred from the donor aggregate to the acceptor aggregate. The model can be used to theoretically simulate many aspects of light-harvesting complexes （LHCs）. By applying the real bio-parameters of photosynthesis, we numerically investigate the efficiency of energy transfer （EET） between the two aggregates in terms of some factors, e.g., the initial coherence of the donor aggregate, the coupling strengthes between the two aggregates and between different pigments, and the effects of noise from the environment. Our results provide evidence for that the actual numbers of pigments in the chromophoric tings of LHCs should be the optimum parameters for a high EET. We also give a detailed analysis of the effects of noise on the EET.
基金supported by the Development Foundation for Electronic and Information Industry(2010),the Science and Technology Commission of Shanghai Municipality(Grant No.10DZ1140502)the Mechatronics Engineering Innovation Group Project from Shanghai Education Commissionthe Key Laboratory of Advanced Display and System Applications(Shanghai University),Ministry of Education,China(Grant No.P201004)
文摘Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes （OLEDs） were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red and white-phosphorescent OLEDs based on Pt complexes are presented in terms of efficiency and color quality.
文摘Lanthanum and nitrogen co-doped SrTiO3 was synthesized using polymerized complex method with Ti(OC3H7)4, SrCl2·6H2O and La(NO3)3·6H2O as starting materials followed by calcinations in NH3. Ethylene glycol and anhydrous citric acid were used as the precursors of synthesis. The samples were characterized using XRD, TEM, DRS, BET, EDX and XPS. The cubic-perovskite type of La/N co-doped SrTiO3 nanoparticle could be successfully synthesized. The photocatalytic activity of SrTiO3 for DeNOx ability in visible light region (λ > 510 nm) could be improved by co-doping of La3+ and N3_. The high visible light photocatalytic activity of this substance was caused by a narrow band gap energy that enables to absorb visible light.
基金supported by the National Natural Science Foundation of China(21221001,and 21471149)Key Research Program of Frontier Science,CAS(QYZDJ-SSW-SLH028)
文摘Compounds with visible-light-induced photoluminescence are particularly attractive in acting as the emitting components of light-emitting diodes and fluorescent probes for biological applications. A new complex [Zn(NCS)_3(MQ)](MQ^+ = N-methyl-4,4?-bipyridinium) with an isolated molecular structure has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and solid-state photoluminescent determination. Crystal data: C_(14)H_(11)N_5S_3Zn, M_r = 410.83, monoclinic, space group P2_1/c, a = 8.809(5), b = 13.138(7), c = 15.580(9) ?, b = 104.433(10)°, V = 1746.2(17) ?~3, Z = 4, D–c = 1.563 g×cm^3, μ = 1.769 mm^(–1), F(000) = 832, the final R = 0.0376 and wR = 0.1243 for 2850 observed reflections with I > 2s(I). In the crystal structure, the zinc atom is tetrahedrally coordinated by one MQ+ ligand and three NCS– groups to yield a tetrahedral configuration. The bond length of Zn–NMQ is clearly shorter than those found in reported Zn(Ⅱ) complexes of 4,4?-bipy. The isolated units are joined by C–H···S interactions to generate a 2D hydrogen-bonding network. This compound displays visible light-induced photoluminescence, which originates from both intraligand charge-transfer of the MQ+ ligand and NCS~–→MQ^+ charge-transfer according to a density of states(DOS) calculation. Moreover, its emission band shows a clear blue shift compared with those of halide compounds.
基金Project supported by the National Natural Science Foundation of China(21571125,21471144)National Key R&D Program of China(2016YFE0114800)the project from State Key Laboratory of Rare Earth Resource Utilization(RERU2016013)
文摘Recently,much attention has been paid to the lanthanide luminescent materials based on the visiblelight sensitization for their potential applications in the fields of bio-imaging and optical devices.In this work,the lanthanide complexes have been covalently bonded to the ordered mesoporous titania（OMT） matrix,and the resulting titania-based hybrid ordered mesoporous materials（named as LnDBOMT,Ln = Eu,Sm,Yb,Nd） were characterized by using Fourier-transform infrared（FT-IR） spectroscopy,small-angle X-ray powder diffraction（SAXD）,N2 adsorption-desorption isotherms,transmission electron microscopy（TEM）,fluorescence spectroscopy,and thermogravimetric analysis.Generally,exciting with visible light is advantageous over UV excitation.Of importance here is that,under excitation with visible light,the LnDB-OMT all show characteristic visible（Eu3＋,Sm3＋） as well as nearinfrared（Sm3＋,Yb3＋,Nd3＋） luminescence of the corresponding Ln3＋ ions（multicolor emission covered from 500 to 1400 nm spectral region）,which is attributed to the energy transfer from the ligands to the Ln3＋ ions via an antenna effect.
基金supported by the Natural Science Foundation of China(No.21171165,21201165 and 91122015)
文摘A series of isostructural d/f molecular compounds Zn（H2L）Ln（NO3）3·CH3OH（Ln = Dy（1）, Tb（2） and Sm（3）） were synthesized by the introduction of a designed multifunctional ligand N,N？,N？？,N？？？-tetra（2-hydroxy-3-methoxy-5-methylbenzyl）-1,4,7,10-tetraazacyclododecan（H4L = C（44）H（60）N4O8）. In the isostructural molecules, each crystallographically independent Zn2＋ and Ln3＋ centers are connected by two phenolic oxygen atoms. For the six-coordinate Zn-（2＋） ion, the coordination geometry can be viewed as a regular bicapped square pyramid. While for the ten-coordinate Ln-（3＋） ion, if each O,O？-chelated nitrate ligand is seen as a single coordination site, the coordination geometry can be viewed as a distorted pentagonal bipyramid. The fluorescent spectra show that compounds 2 and 3 exhibited characteristic sharp emissions of Tb-（3＋） and Sm-（3＋）, respectively, while compound 1 was found to be a single-component white-light-emitting complex in the solid state. Thermal stabilities of the three compounds were investigated by using thermal gravimetric analysis. In addition, the thermal decomposition of compound 1 was confirmed by temperature-dependent powder X-ray diffraction technique.
