最新刊期
卷 31 ， 期 6 ， 2010
- 摘要：A new material group, DPVBi and Bphen, are presented to form electroplex with their efficient white emission in a p-i-n OLED. The experimental results bear out that the interfacial phenomenon between DPVBi and Bphen originates from electroplex but not exciplex. By introducing p-i-n structure, the white OLEDs exhibits relatively high peak luminance of 9 050 cd/m2, and power efficiency of 2.63 lm/W. Further more, the Commission Internationale De lEclairage coordinates of resulting emission varies gradually with increasing forward bias. Consequently, a consistent white color is obtained. It affords more opportunities in facilitating the fabrication process of white OLEDs.112|219|4更新时间：2020-08-12
- 摘要：A kind of two-sided symmetrical rectangular metal gratings used in OLED structures as electrode is proposed. The exciting, coupling and transmiting of Surface plasmon polaritons are similated and analyzed with Finite-difference Time-domain(FDTD) method. Particularly the relation of light-output efficiency and periods, the groove width, the grating height, the thickness of the metal film, the angel of incident light are analyzed, respectively. By optimizing this gratings parameters,its transmissivity can be 1.77 times of traditional metal electrode.Providing technical and theoretic support to the desigh of high efficiency light out-coupling devices based on surface plasmon polaritons.关键词：light-output efficiency;metal grating;finite difference time domain(FDTD);surface plasmon polaritons(SPPs)125|229|4更新时间：2020-08-12
- 摘要：Structural characterization of the luminescent material Ca2GeO4:Tb3+ was carried out with X-ray powder diffraction analysis. The VUV luminescence property of the green emitting phosphor Ca2GeO4:Tb3+ was studied in details. When absorption at 172 nm, the phosphor shows bright green emission at 549 nm due to the 5D4 →7F5 magnetic dipole transition, the optimum Tb3+ doping concentration is x=0.05. The absorption intensity at 147 nm and 172 nm is almost 1.5 and 1.7 times of that at 218 nm, respectively. It is worthy to point out that the intense excitation at 147 nm and 172 nm in UVU region makes it undoubtedly convenient to apply in PDP, because the wavelength of excitation source in PDP is mainly at 147 nm and 172 nm. In addition, the Al3+ co-doping enhances the green emission from Ca2GeO4:Tb3+ by about 2 times under VUV excitation. The excellent luminescence properties make it possible as a good candidate for the PDP application.关键词：germanate;VUV;luminescence120|81|0更新时间：2020-08-12
- 摘要：Er3+-doped (B2O3)y(ZnO)1-x-y(P2O5)x glass with excellent optical properties was prepared. The glass was proved to have the high stability by the investigation of the durability in boiling water. The spectral characters of the glass at about 1.5 μm changed a lot with the doped contents of both Er3+ and B2O3. Comparing with Er3+-doped zinc phosphate glass systems, the glass prepared in our laboratory exhibits a larger quenching concentration and a much broader emission band at 1.54 μm.关键词：near-infrared photoluminescence;Er3+ doping;phosphate glass104|56|0更新时间：2020-08-12
- 摘要：Er3+/Yb3+ co-doped phosphate glass-ceramics have been fabricated and characterized,the formation of Er(PO3)3 and Yb(PO3)3 nanocrystals were studied using X-ray diffraction. The intensity parameters,the spontaneous radiative transition probabilities,the branching ratios,and the radiative lifetimes of Er3+ in glass ceramics were calculated based on the Judd-Ofelt theory.For Er3+ 4I13/2→4I15/2 transition,lifetime is 8.625 8 ms.Strength parameters are Ω2=6.33×10-20 cm2, Ω4=1.41×10-20 cm2, Ω6=1.09×10-20 cm2.According to McCumber theory,we calculated the stimulated emission cross section,the number is 3.6×10-21 cm2.We also studied the fluorescence properties of crystals, and the crystal has been pumped up in laser under the green fluorescence conversion.116|129|1更新时间：2020-08-12
- 摘要：Co-precipitation together with spray dry processing was introduced to prepare YAG:Ce3+ precursor first time. YAG:Ce3+ phosphor could be obtained after heat-treating, milling and further acid and alkali washing. Effects of spray suspension concentration, heat treatment temperature and the acid and alkali washing on particle morphology, type of crystal phase and photoluminescence (PL) intensity of the powder were investigated. The precursor particles appeared nearly spherical balls with fragments in the surface, smooth or rugged ones when the concentration of spray suspension was 0.2, 0.4 and 0.6 mol/L, respectively. YAG phase could be obtained by heat-treating the smooth spherical precursor at 1 100 ℃ for 4 h. The PL intensity of the powder raised with heat-treating temperature increased up to 1 550 ℃. Agglomerate-free YAG:Ce3+ phosphor with good preferences could be obtained by acid and alkali washing which could remove scraps adhering on particles and break aggregates between them.关键词：co-precipitation;spray;acid and alkali wash;white LED;yttrium aluminum garnet135|100|2更新时间：2020-08-12
- 摘要：Energy up- and down-conversions are two efficient methods to resolve spectral mismatch. This paper reports down-conversions in solar cells based GaAs. The energy is transfered from Tm3+ 1I6→1G4 749 nm (13 356 cm-1) transition to Er3+ 4I9/2→4I15/2, 796 nm (12 563 cm-1) by the cross relaxations, under excitation of Tm3+ 3H6→1I6, 294 nm (34 364 cm-1), where the 1G4 level is used as an intermediate state. Then a high energy ultraviolet photon 294 nm can be cut into a near infrared 796nm photon and a blue 476 nm photon. Energy transfer efficiency and quantum cutting efficiency were estimated with experimental data. The spectral mismatch can be improved by the quantum cutting to enhance the conversion efficiency of solar cells.关键词：down-conversion;cross relaxation;solar cell;ion-couple107|122|1更新时间：2020-08-12
- 摘要：A series of Er3+ /Eu3+ co-doped, Yb3+ /Er3+ /Eu3+ co-doped borosilicate glasses have been prepared by high-temperature solid-phase melting. Under 978 nm semiconductor laser excitation, the up-conversion emission spectra of the samples were measured, and up-conversion mechanism was analyzed. The emission intensities of Eu3+ ions at 595 nm and 692 nm were enhanced with increasing concentration of Er3+ , Yb3+ , respectively. And emission intensity at 692 nm is stronger than that at 595 nm. The cooperation up-conversion and the energy transfer between Yb3+ and Eu3+, Er3+ and Eu3+ lead to a strong up-conversion emission of trivalent europium ions.127|49|0更新时间：2020-08-12
- 摘要：In this work,Y(PV)O4:Eu3+ phosphors were coated with Y(OH)3 by the coprecipitation process. The surface morphology and the crystal structure were characterized by SEM and XRD, respectively. The results indicated that the surface of Y(PV)O4:Eu3+ phosphors are evenly coated by Y(OH)3 and the crystal structure of the coated Y(PV)O4:Eu3+ phosphors remains the same with the uncoated samples,i.e. after surface treatment,the luminance centre of Eu3+ does not shift,the emission is still at about 620 nm. The color coordinates of Y(PV)O4:Eu3+ are x=0.660,y=0.340, so it can meet the requirement of PDP. The emitting spectra of Y(PV)O4:Eu3+ phosphor particles coated with Y(OH)3 and without coating were investigated under 308 nm excitation. The results demonstrated that the initial luminance of coated Y(PV)O4:Eu3+ phosphors is higher than the uncoated samples. This method is simple,convenient and economical as compared with other methods.关键词：Y(PV)O4：Eu3+;coprecipitation;phosphor;PDP108|92|1更新时间：2020-08-12
- 摘要：The research on Plasma display panel (PDP) phosphors has gained much attention. The green PDP phosphor is an important component due to its highest brightness in three-color-based phosphors. Existing and developing green-emitting phosphors include Mn-activated silicates and aluminates, and Tb-activated phosphates and borates systems. Mn-activated silicates and aluminates have high quantum efficiency and excellent color coordinate, but low stability to vacuum ultraviolet (VUV) radiation and long decay time. Tb-activated phosphates and borates have suitable decay time and high stability to VUV radiation, but low brightness and color purity. This work investigates the luminescent performance of single BaAl12O19:Mn2+, YPO4:Tb3+, and especially their blends. The result indicates that the blends of BaAl12O19:Mn2+ and YPO4:Tb3+ can effectively combine their respective advantages to improve the overall luminescent performance of green-emitting phosphors for PDP application.关键词：rare earth;green-emitting phosphors;PDP111|96|1更新时间：2020-08-12
- 摘要：The absorption spectra of crystals CsI:Tl contain 310 nm (4.0 eV), 270 nm (4.6 eV) and 245 nm (5.1 eV) three characteristic features within the region 230~320 nm at the room temperature. The same PL spectra are observed under the excitations of the three UV lights 310,270,245 nm. These PL spectra are similar to the radioluminescence (RL) under the X-ray excitations from tungsten (W) target tube. Both PL and RL are composed of luminescence at 3.10, 2.55, 2.25, 2.10 eV using Gauss deconvolution program. However, the 2.10 eV component in RL is stronger than that in PL while the 2.55 eV component is weaker. Such changes are caused from the radiation defects Tl+Va+ and Tl0Va+ created by X-ray irradiations, which lead to increasing Tl2+-STE and its emission (2.10 eV) accompanied by its self-absorption (2.55 eV) in CsI:Tl. The results show that X-ray induces the radiation defects more easily than UV light, which might affect luminescence features of the crystal.关键词：scintillant crystal;thallium doped cesium iodide;radiation defect;radioluminescence204|168|1更新时间：2020-08-12
- 摘要：We have investigated the excitation-intensity-dependent optical properties of CdSe/ZnSe self-assembled quantum dots (QDs) at different temperature. When excitation intensity (I) is varied by three orders of magnitude, the photoluminescence (PL) morphology and peak positions appear to be independent on excitation intensity.The nonlinear coefficient k obtained by a relation of L∝Ik in the temperature ranges of 21~300 K shows regularity which is described in three temperature regions:k is close to 1, when the temperature is below 120 K, it slightly decreases with increasing temperature in ranges of 120~200 K and it rapidly decreases from 0.946 to 0.870 with the temperature in the ranges of 200~300 K. Taking the temperature dependence of PL into account, we have confirmed that the bound excitonic recombination is a dominant recombination mechanism below 120 K. The nonlinear coefficient k monotonously decreases in the temperature ranges of 120~300 K, which is attributed to increasing transition from free-to-bound (FB) exciton with increasing temperature. Furthermore, the temperature dependence of integrated PL intensity reveals that defects and dislocations in the material provide nonradiative channels to quench the luminescence.关键词：nonlinear coefficient;photoluminescence;self-assembled quantum dots104|66|1更新时间：2020-08-12
- 摘要：The electron structures and optical properties of the wurtzite Cd1-xMgxSe systems are calculated by the first-principles ultra-soft pseudo-potential plane wave approach based on the density functional theory. The obtained results indicate that the top of valence band is fundamentally determined by the Se4p electrons and nearly unchanged; the bottom of conduction band is determined by Se4s electrons and Cd5s electrons and it is removed to higher energy direction with the increase of Mg concentration, thus the band gap is broadened. The peaks in the imaginary part of dielectric function and the peaks in the real part of refractive index are found to have blue-shifts as Mg concentration increases. Our results are agreement with the experimental results.关键词：Cd1-xMgxSe;electron structure;optical properties;first-principles105|105|3更新时间：2020-08-12
- 摘要：ZnO:Ga (GZO) transparent conductive thin film was deposited on p-GaN acting as the current spreading layer, but it leads to a large contact barrier because of the formation of Schottky contact. However, ohmic contact is of great importance to powered LED. In order to decrease the contact barrier, HCl and NaOH treatment of the p-GaN surface and annealing were employed in this work. The effects of different chemical treatment and annealing on p-GaN/GZO contact property were studied. It is obvious that solutions of alkaline treatment of p-GaN surface can decrease the interfacial barrier, which led to ohmic contact, and the barrier can be lightly increased by annealing.112|148|2更新时间：2020-08-12
- 摘要：ZnO-based heterojunction light-emitting diodes have been fabricated on p-type GaAs substrate by plasma-assisted molecular beam expitaxy. An electron-blocking MgO layer between thin ZnO film and p-GaAs substrate plays a key role in improving performance of the diodes. Comparing with the n-ZnO/p-GaAs heterojunction, the ZnO/MgO/p-GaAs heterojunction shows a typical diode characteristic with a forward threshold voltage of 3 V. Electroluminescence measurement indicates that the ZnO/MgO/p-GaAs heterojunction has a visible emission band attributed to the defect-related recombination in the ZnO layer and an ultraviolet emission peak.关键词：ZnO;molecular beam epitaxy;electroluminescence;light-emitting diode130|566|1更新时间：2020-08-12
- 摘要：The growth of multilayer GaSb(quantum dots)/GaAs and their luminescence property have been studied. The results show that the number of layer seems no obvious effect on the density of quantum dots. However, increasing the number of layer leads to the size of quantum dots becoming larger. Furthermore, the quantum dots accumulate as the number of QD layers reaches to a certain degree and some holes are formed in the location of the quantum dot accumulated,as the thickness of quantum dots increases there will be some holes just on the locations the quantum dots gathered. The results suggest that relatedness effect exists between each quantum layer and the GaAs covering layer can not grow well at the location of the accumulated GaSb quantum dots.As a result, the GaSb quantum dots become accumulate easier and evaporate easier in the following GaSb quantum dots grown, which will lead to the forming of the hole.The PL spectra of GaSb (quantum dots)/GaAs shows a broad photoluminescence peak of quantum dots,due to the broad distribution of the size of the quantum dots.关键词：LP-MOCVD;GaSb quantum dots;PL spectrum;relatedness effects121|130|0更新时间：2020-08-12
- 摘要：Temperature-dependent photoluminescence (PL) of InGaN/GaN multiple quantum wells (MQWs) is studied. Three samples have different percentage composition of In: 10%, 14% and 17%. With increasing temperature, we can observe "S-shaped" behavior of the peak energy for all three samples. Because the second temperature turn of the "S-shaped" curves are different for each samples, and the blueshift energy of 10 meV in our samples is less than the energy shift result from QCSE, the S-shape is unrelated with QCSE. By using multi-channel Arrhenius plot formula, the samples' activation energies are calculated, which stand for the level of localized In-cluster. And it is found that both the activation energies and the second temperature turn of the "S-shaped" curves increase with increasing the content of indium for three samples. This phenomenon can be demonstrated by the reason that the sample which containing much In has lager activation energy, the photo-carriers need much thermal energy to get out of the local potential minima induced by In-cluster. These results further illustrate that the emission of InGaN/GaN multiple quantum wells is due to the radiative recombination of excitons localized in potential minima induced by In-cluster.关键词：In cluster;InGaN;temperature-dependent PL;activation energy151|114|3更新时间：2020-08-12
- 摘要：The Schrdinger equations of electron and hole and Poisson equations are solved self-consistently to obtain the ground-state energies on the basis of the numerical computation of ordinary differential equations. The built-in electric field induced by spontaneous and piezoelectric polarization, the screening effect due to the free electron-hole gas and the applied external electric field are considered. For example, a typical GaN/AlxGa1-xN wurtzite nitride strained quantum well is taken to calculate the eigen energies of electron and hole as well as the corresponding eigen-wavefunctions. The results show that the built-in electric field is offset by the electric field applied along the same direction as the growth of quantum well. The bending degree of the well structure is slightly reduced. The electron or hole wave function then moves along or away from the electric field direction to the center of the well leading to the increase of wave peak value and decrease of tunneling probability. It is also found that in a fixed external electric field case, the ground-state energy levels of electron and hole in the quantum well significantly decrease with increasing the well width and prominently increase as the Al component increases. That is to say, the external electric field certainly weakens the built-in electric field and the quantum confinement has a significant impact on the electronic (hole) ground-state energy.关键词：time-independent Schrdinger equation;screening of electron-hole gas;built-in electric field;eigen-state111|316|1更新时间：2020-08-12
- 摘要：We analyze the thermal characteristics of 1 W GaN-LED as function of input power. Based on the transient thermal measurement, the relationship of junction-ambient thermal resistance and input power is discussed. The thermal resistance and the thermal capacitance in the heat flow path can be captured by the diffe-rential structure function and cumulative structure function, offering reliable evidence for thermal management. The devices exhibit a decrease of effective thermal resistance from 14.3 K/W to 12.5 K/W when the input current increases from 100 mA to 500 mA at the heatsink temperature of 25 ℃. However the effective thermal resistance gradually decrease from 12.5 K/W to 12.3 K/W with the input current from 500 mA to 800 mA. On the other hand, when the input current increases from 900 mA to 1 650 mA, the change trend is completely opposite, while the device exhibits an increase of effective thermal resistance from 14.7 K/W to 15.4 K/W. With the same devices, the different trends of thermal resistance go with different current regions. All packaged LEDs can be simplified to the model composed of an ideal diode and a series resistance.关键词：light emitting diode;structure function;series resistance;power effect103|150|2更新时间：2020-08-12
- 摘要：The feasibility of spectral tunable LED-based light source was verified. The source is capable of producing any spectral distribution. According to the measured LED spectral distribution, an asymmetric Gaussian function model was proposed to fit the individual LED spectral distribution. A variety of different LEDs with different peak wavelengths were utilized to synthesize the required spectral distribution. In theory, the least square fitting for any spectrum is realized. The experimental results of synthesis of typical spectral distribution are satisfactory. Finally, based on the analysis of experimental data, this paper put forward some points for the engineering practice.关键词：LED;spectral distribution;spectral synthesis;non-negative least squares solution166|198|15更新时间：2020-08-12
- 摘要：A numerical model of the thin composite disk side-pumped by ring laser-diode arrays (LDA) is set up. LDA fast axis is upright to disk face and is compressed. Under considering the influence of temperature correlation of the thermal conductivity of the material and heat transfer coefficient between air and medium, based on the thermal conduction equations, the pump distribution and the transient distributions of temperature in the thin disk are calculated by a finite element analysis method. The influence disciplinarian of the number of LDA, the pump distance, the light divergence angle and the absorption coefficient of thin disk on pump distribution and absorption efficiency of thin disk are analyzed. The influence disciplinarian of the pump power, heat transfer coefficient, cooling fluid temperature and time on transient distributions of temperature in the thin disk are discussed. The theoretical results accord with interrelated experiment and provide theoretical reference for the design of solid laser pumped by LDA and experimental analysis.关键词：composite thin disk laser;laser-diode arrays (LDA) side-pumping;pump distribution;transient temperature distribution;finite element method106|194|0更新时间：2020-08-12
- 摘要：Large area aligned identical silicon nanowires array were prepared on mono-crystalline n-Si(100) wafers by the metal catalyzed chemical etching method under normal conditions(room temperature,1.01×105 Pa). The morphologies of prepared samples and reflection spectrum are analyzed, the diameter of SiNWs is 10~50 nm,after etching time of 15, 30 and 60 min the length of SiNWs is 9,17,34 μm, respectively. The reflection spectrua show that the obtained SiNW arrays could drastically suppress the optical reflection over a wide spectral bandwidth ranging of 300~1 000 nm, the reflectance is about 2.4%.The mechanism of antireflectivity and difference among the samples are analyzed.关键词：metal catalyzed chemical etching;silicon nanowire arrays;antireflection105|148|2更新时间：2020-08-12
- 摘要：In this paper, oleic modified LaF3:Er,Yb nanoparticle (NP) is prepared by micro-emulsion method. This NP has a excellent solubility in organic solvent and NPs doping concentration can reach as high as 50%. Observed by TEMs photograph, most of NPs diameter is about 6~10 nm; there is hexagonal LaF3 structure in the materials by X-ray diffraction pattern; NP shows potential high gain bandwidth because full width at half maximum (FWHM) is 79 nm which is bigger than inorganic matrix erbium doped waveguide amplifier (EDWA); 100 μs lifetime of the 4I13/2 energy level is also measured. At last, a planar waveguide is fabricated by semiconductor process, a relative gain of 3.2 dB can be got in a 1.9 cm length sample with 1 mW signal power. The relationship between gain and nanopaticle diameter is also analyzed.关键词：LaF3：Er;Yb nanoparticle;waveguide amplifier;relative gain;lifetime108|53|1更新时间：2020-08-12
- 摘要：DBD(Dielectric-Barrier Discharges)-PECVD (Plasma Enhanced Chemical Vapor Deposition) was used to prepare porous nanoparticle silicon-based film from SiH4/Ar/H2 at pressure of 0.5 MPa. Pulsed negative bias voltage was introduced to modulate the process and character of the films. The optical emission spectrum and Fourier transform infrared spectrum were used to study the deposition process. The dissociation of SiH4 was indicated form specific spectrum of SiH*(A2Δ→X2Π 0-0) at 412 nm. When the pulsed duty cycle changed from 0.162 to 0.864, the stretch vibration band of Si—O—Si at 1 070 cm-1 and the bending vibration band of Si—O—Si at 800 cm-1 increased. At the same time, the bending vibration band of Si—H at 930 cm-1 decreased. More Si—O—Si structure was formed as the increase of the duty cycle.关键词：porous silicon-based nanoparticle film;optical emission spectrum;Fourier infrared spectrum;duty circle;dielectric barrier discharge plasma120|137|0更新时间：2020-08-12
- 摘要：Rare earth metal complexes have special characteristics, such as extremely narrow emission bands and high internal quantum efficiencies, which are suitable to be used as the emission materials. Eu(Ⅲ) complexes are a kind of good red luminescence materials and Tb(Ⅲ) complexes are a kind of good green luminescence materials. During the past decade, many ternary rare earth complexes have been reported, but quaternary rare earth complexes are seldom reported. In this article, eight quaternary complexes of Eu(Ⅲ) and Tb(Ш) have been synthesized with benzoic acid(BA), p-phthalic acid(p-PA), o(m,p)-methylbenzoic acid as the first ligand and the neutral phenanthroline as the second ligand. They were characte-rized by EDTA titration, elemental analysis and IR methods. Their compositions were: Eu2(p-PA)(BA)4-(phen)2·2H2O, Eu2(p-PA)(o-MBA)4(phen)2·2H2O, Eu2(p-PA)(m-MBA)4(phen)2·2H2O, Eu2(p-PA)(p-MBA)4(phen)2 ·H2O, Tb2(p-PA)(BA)4(phen)2·2H2O, Tb2(p-PA)(o-MBA)4(phen)2· 2H2O, Tb2(p-PA)(m-MBA)4(phen)2·2H2O and Tb2(p-PA)(p-MBA)4(phen)2·H2O, respectively. In these complexes, the metal ions were bonded to the oxygen atoms of carboxylate and the nitrogen atoms of phen. The excitation and luminescence spectra of the complexes were carried out at room temperature. Four kinds of Eu(Ⅲ) complexes emit intense red fluorescence under ultraviolet excitation. The intensity order of the strongest emission peak 5D0 →7F2(614 nm) for these Eu(Ⅲ) complexes were: Eu2(p-PA)(BA)4-(phen)2·2H2O＞Eu2(p-PA)(o-MBA)4(phen)2·2H2O>Eu2(p-PA)(p-MBA)4(phen)2·H2O＞Eu2(p-PA)(m-MBA)4(phen)2·2H2O. Four kinds of Tb(Ⅲ) complexes emit intense green fluorescence under ultraviolet light. The intensity order of the strongest emission peak 5D4→7F5 (545 nm) for these Tb(Ⅲ) complexes is: Tb2(p-PA)(p-MBA)4(phen)2·H2O＞Tb2(p-PA)(o-MBA)4(phen)2·2H2O＞Tb2(p-PA)(BA)4(phen)2·2H2O＞Tb2(p-PA)(m-MBA)4(phen)2·2H2O.关键词：europium;terbium;quaternary complex;fluorescence spectra101|88|0更新时间：2020-08-12
- 摘要：The complexes of rare earth ion (Tb3+, Eu3+) with acetic acid and ammonium acetate ligand have been synthesized. The transparent photoluminescent polyacrylamide materials were prepared by aqueous polymerization with acrylamide monomer. Their fluorescent properties were studied. Both complex and polymer display strong characteristic emission of Tb3+ ion or Eu3+ ion. The decay curves of Tb3+ ions 5D4→7F5 emission show that there are two fluorescent lifetimes of Tb3+ ion 5D4→7F5 emission in both complex and polymer. The polymer has longer apparent fluorescent lifetime but lower quantum efficiency than corresponding complex.关键词：rare earth complex;polyacrylamide;fluorescent lifetime;photoluminescence109|171|1更新时间：2020-08-12
- 摘要：Nine doped europium benzene-1,3,5-tricarboxylate complexes have been synthesized and characterized. Elemental analysis, rare earth coordination titration, IR spectra, UV absorption spectra and TG-DTA were used to characterized these complexes. The studies of the fluorescence spectra and lifetimes of the nine complexes show obviously difference. Compared with binary complex of EuL·6H2O(1), the ternary complex EuLL'1.5·2H2O exhibits stronger luminescence intensity. This result indicates that the fluorescence intensities of the complexes depend on ligands. In the binary complex the ligand (btc) transfers some energy to Eu3+, but in ternary complexes both the ligands (btc and phen) transfer more energy. The fluorescence peak positions of the other seven are similar to (1) and (2), but the luminescence intensities of these complexes are obviously different. The positions of Eu3+ emission peak of the complexes do not change, indicating that the introduction of doped rare earth ions or transition-metal ions does not influence the energy level of Eu3+ in the complexes. The dinuclear complexes, which contain the metal ions Y3+, La3+, Zn2+ and Cd2+ without unsa-turated d-layer or f-layer electrons, display sensitization and strengthening to fluorescence properties of those complexes, respectively. Therefore, the energy absorption by organic ligands will not be consumed by the d-d or f-f transfer. In this manner, Eu3+ absorbs much more energy through intramolecular energy transfer and luminous intensity is enhanced. Gd3+ has inert half-full 4f7 electronic configuration, so the luminous intensity of (5) is also strong and similar with (3) and (4). Complexes (8) and (9), containing Mn2+ and Ni2+, respectively, exhibit fluorescence quenching, which is caused by the unsaturated d-layer electrons consuming the energy in the form of radiative transition.130|100|1更新时间：2020-08-12
- 摘要：In this paper, imidazo phenanthroline(IP) and 2-diphenylamine carbonyl benzoic (HDPAB) were synthesized. Then HDPAB was used as the first ligand and IP as the secondary ligand, a new ternary organic terbium complex Tb(DPAB)3IP was prepared. In the same condition, with the same first ligand, Tb(DPAB)3phen was prepared where phen as the second ligand. The structures and compositions of the ligands and ternary complexes were confirmed by elemental analysis, IR spectra and UV spectra, the fluorescence properties of the two terbium complexes were also studied. Elemental analysis demonstrated that the compositions of the ternary complexes were Tb(DPAB)3IP and Tb(DPAB)3phen. IR spectra indicated that rare earth Tb3+ ion coordinated with six oxygen atoms of three benzoic acid ligands and two nitrogen atoms of the second ligand. UV spectra showed that the main absorption was from HDPAB in the ternary complex.Fluorescence spectra demonstrated that two kinds of ternary organic terbium complexes could emit characteristic fluorescence of rare earth Tb3+ and the second ligand IP had stronger conjugation system. With the excitation of ultraviolet, the energy absorbed by the ligands in the complexes could be transfered to the rare earth Tb3+ ion,so they could emit characteristic fluorescence and the fluorescence intensity of Tb(DPAB)3IP was obviously higher than that of Tb(DPAB)3phen. Thus the appropriate secondary ligand of imidazo Phenanthroline (IP) obviously enhanced the fluorescent intensity of terbium complex. So, the new ternary organic terbium complex of Tb(DPAB)3IP is an excellent green-emitting material.关键词：terbium;synthesized;ternary complex;luminescence106|81|2更新时间：2020-08-12
- 摘要：Supramolecular system has received great attention in the fields of catalytic, magnetic, liquid crystal materials, and bio-organic chemistry in recent years. They are composed of monomeric units through non-covalent intermolecular interactions including intermolecular hydrogen bond and π-π stacking interaction. The result is that the energy of the molecular system is greatly reduced and the molecular structure becomes more stable, which leads to the emergence of new properties of the optics, electricity, magnetic, and biological activity. Till now, many supramolecular polymers with one-dimensional chain, two-dimensional layer or three-dimensional open framework structures have been reported. In this work, a 3-D supramolecular compound (C20O2H14)(C12N2H8) (BP1) was synthesized and characterized by elemental analysis, IR, 1H NMR and single-crystal X-ray diffraction. In the crystal structure, multiform hydrogen bonds and π-π stacking interactions lead to a 3-D supramolecular compound. At room temperature in DMSO solution,the compound has purple fluorescent emission at 373 nm, when excited at excitation wavelength of 342 nm. Fluorescent emission of the compounds originates from π*→π transitions in molecular. The crystal belongs to triclinic, space group P1 with a=1.087 8(2) nm, b=1.125 2(2) nm, c=1.168 0(2) nm,α=97.89(3)°, β=110.91(3)°, γ=109.62(3)°,V=1.203 2(4) nm3. Z=2, R1=0.053 1, wR2=0.163 4, GOF is 1.034.关键词：synthesis;supramolecular;crystal structure;fluorescent properties97|55|0更新时间：2020-08-12
- 摘要：Fluorimetric liquid method was used for the analysis of neodymium resulting from the formation of fluorescent complex among neodymium, alanine and imidazole, and the effects of various factors were discussed. The optimum reaction conditions of the complex are n(alanine):n( imidazole)= 5:1, pH=5.The optimum excitation light wavelength is 220 nm, the emission light wavelength 350 nm, the excitation slit 5 nm, and the emission slit 10 nm. On the basis of these conditions, neodymium(Ⅲ) can be determinated at a low detection limit of 0.5 μg/mL. Further, neodymium(Ⅲ) concentrations of neodymium oxide and neodymium ceramic product were determined using this method.关键词：neodymium(Ⅲ);alnine;imidazole;liquid of fluorimetry101|120|1更新时间：2020-08-12
- 摘要：Through the transmission matrix method, this research about defect mode of mirror symmetry of slowly varying quasi-periodic one-dimensional photonic crystal shows that: with the periodicity increases of the mirror symmetry slowly varying quasi-periodic one-dimensional photonic crystal, the width of photonic band gap broadening by degrees. After the introduction of defect, the defect mode appears; and along with the increase of defect layers thicknesses and its medium refractive index, the wavelength of this defect mode moves to the long-wave direction.关键词：mirror symmetry;slowly varying quasi-periodic structure;photonic crystals;defect mode;transfer matrix100|101|1更新时间：2020-08-12
- 摘要：According to the coupling differential equations of the Stokes and anti-Stokes, the pump wave is linearly polarized and aligned with the x-axis direction. The gain coefficients have been reduced for the Stokes and anti-Stokes which simultaneously act of stimulated Raman scattering and parametric amplification in the same x polarization. The gain changes with mismatch Δk2 and normalized distance z/L in dispersion-decreasing fiber are obtained. It is observed that gain coefficient changes with the mismatch Δk2 is symmetrical when non-linear coefficient γ=0, in normal dispersion regime and anomalous dispersion regime. The gain will arise a peak and then with the Δk2 and z/L increases gradually reduce in the anomalous dispersion regime when non-linear coefficient γ≠ 0. At the same time the feature about energy ratio of Stokes and anti-Stokes Eax/Esx reduced rapidly with increase of mismatch Δk2.关键词：stimulated raman scattering;parametric amplification;gain coefficient;coefficient mismatch;normalized distance109|171|1更新时间：2020-08-12
- 摘要：Dynamic model of delayed luminescence of spinach leaves was proposed based on the mechanism of delayed luminescence in biological system. Delayed luminescence of spinach leaves reduced with time according to double-exponential law,it showed that delayed luminescence of spinach leaves comes from fast and slow items of light-emitting elements. The characteristics of delayed luminescence could be accurately described by parameters such as initial photon number I(0),integrated intensity I(T) and decay time of delayed luminescence. Treated by solution of 10% H2O2, I(T) and I(0) decreased rapidly with treatment time, the changes of integrated intensity I(T) is proportional to changes of initial photon number I(0). Two decay times of the fast and slow items of light-emitting elements gradually decreased. The changes of I(T) and I(0) of delayed luminescence could represented decline in photosynthetic capacity and metabolic intensity of cell. The changes of decay times suggested that polypeptide D1 and D2 in PS Ⅱ of photosynthetic cells could be damaged by H2O2.关键词：delayed luminescence;dynamic model;spinach;H2O2 stress101|101|2更新时间：2020-08-12
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