最新刊期
卷 13 ， 期 3 ， 1992
- 摘要：The dissipative current waveform,brightness waveform and charge voltage characteristics of the TFEL device with MISIM structure have been measured by using a bridge circuit and Sawyer-Tower circuit,in which a sinusoidal voltage is used.It is observed that the positive half cycle waveform of the dissipative current and the negative one are asymmetry.The brightness waveform has the same property.124|66|1更新时间：2020-08-11
- 摘要：At present there is no literature about luminescence of exciton-exciton(Ex-Ex)interaction in ZnSxSo1-x,MIS diodes under forward-biased direct current excitation.This paper reports the first observation of two emission bands P and P2 at 77K with direct current density(J)from 20-50mA/mm2 in pure ZnSe and ZnS0.22Se0.78 MIS diodes which are attributed to the different Ex-Ex interaction.Samples for this study were grown by the sublimation method[6].ZnSe(x=0)and ZnS0.22Se0.78 single crystals were selected.The low resistivity crystals were obtained by annealing in molten zinc at 900-950℃ for 100h,and then ZnSe and ZnS0.22Se0.78MIS diodes were prepared fron these annealed crystals.97|35|0更新时间：2020-08-11
- 摘要：Na5 Eu(WO4)4 is a good stoichimetric host luminescent material.The light emission eomes from high concentration host ions Eu3+.The effects of hydropressure on fluorescence of Eu3+ in Na5 Eu(WO4)4 have been invistigated under 0-80kbar at room temperature using a diamond anvil high pressure microspeetroscopic system.According to crystal field theory,the crystal parameter formulars of energy levels of Eu3+(in approximatary D2d point group symmetary site)are determind and fit with the experimental data of energy levels under high pressure.Then the ratios of crystal parameter variation Bkq(kq=20、40、44、60 and 64)to pressure variation ΔP are calculated.100|51|2更新时间：2020-08-11
- 摘要：Na5 Eu(WO4)4 is a good stoichimetric host luminescent material.The light emission eomes from high concentration host ions Eu3+.The effects of hydropressure on fluorescence of Eu3+ in Na5 Eu(WO4)4 have been invistigated under 0-80kbar at room temperature using a diamond anvil high pressure microspeetroscopic system.According to crystal field theory,the crystal parameter formulars of energy levels of Eu3+(in approximatary D2d point group symmetary site)are determind and fit with the experimental data of energy levels under high pressure.Then the ratios of crystal parameter variation Bkq(kq=20、40、44、60 and 64)to pressure variation ΔP are calculated.101|48|0更新时间：2020-08-11
- 摘要：Angular Overlap Model(AOM)is applied to Eu3+:Ln2O2S(Ln=Lu,Y,Gd,La)crystal series while two sorts of ligand(oxygen and sulfur with distance R1 and R2)are considered.The results show that the cova-lency between central ion and ligands varies in the order Lu~Y>Gd>La,and for σ-bonding the covalency of Ln-O bonding is larger than that of Ln-S bonding.Our conclusions also indicate that at least both parameters eσ and ex must be considered in practical calculationsions for this crystal series.If we only consider parameter eσ,larger deviation will occur,compared to some other crystals,such as GdVO4,LuVO4 and YVO4 where parameter eσ is dominant.This gives us a hint that the value of each parameter depends on the structure and components of the studied crystal.118|40|0更新时间：2020-08-11
- 摘要：Cathodoluminescence spectra of a suit of natural fluorites from several main fluorite deposits of China were measured.The main lines in the spectra of all samples studied,except Mo-25,are due to Dy3+ and Sm3+ ions substituting for Ca2+.A few lines arising from Er3+,Pr3+ and Tb3+ are also observed.The relative intensities of spectral lines are closely related to the relative contents of individual rare earth ions in the sample.Group theory analysis shows that the local symmetry of Dy3+ in fluorite is lower than cubic and/or there may exist more than one Dy3+ environments.In the spectrum of Mo-25,only a broad band centered at 490 nm occurs in the visible region.This band is probably due to the 4T1gS(G)-6A1g(G)transition of Mn2+ ions.Because the crystal-field splitting parameter Dq of Mn2+ in fluorite is anomalously low,grean emission is observed,which is unusual for eightfold-coordinated Mn2+,139|71|4更新时间：2020-08-11
- 摘要：The luminescence properties of Eu3+ and Dy3+,the influence of Bi3+ on the emission intensity of Dy3+,and the concentration and thermal quenching of Dy3+ in Ba2RV3O11(R=Y,Gd,La)are reported in this paper for the first time.The dependences of charge transfer band of V3O117-,the Red-to-Orange intensity ratio(R/O)of Eu3+ and the Yellow-to-Blue intensity ratio(Y/B)of Dy3+ on the rare earth ions R3+ were systematically investigated.Strong absorption band of V3O117- appears in the excitation spectra of Eu3+ or Dy3+,this means that V3O117- can sensitize Eu3+ or Dy3+(Figures 2 and 3).It is shown from the luminescence spectra of Eu3+ that Eu3+ ions occupy sites with deviation from inverse center in Ba2YV3O11 and Ba2GdV3O11,because the intensity of 5D0-7F2 transition of Eu3+ is stronger than that of 5D0-7F1 transition in these two mat ixes.However,Eu3+ ions occupy sites without inverse center in Ba2RV3O11,as the 5D0-7F0 transition of Eu3+ appears in the matrix(Fig.2)106|31|0更新时间：2020-08-11
- 摘要：In this paper,the investigation on brightness(B),efficiency(η),capacit-ivc currant(IC),loss current(IR)and dielectric loss angle tangent(tgδ)of DCEL devices operated under AC voltage is reported.The results indicate that the effective electric field(E),the width of the emission region and the distribution rate in voltage are frequency dependent.It is concluded that the IR-f dependence can be divided into two regions,In the region of about 0-1kHz,IR increases slowly with increasing frequency and tgδ-f dependence is in accordance with that of leak conduction current loss in dielectric.This means that the dominant part of IR in 0-1kHz region is leakege current.This region can be called leakege current region.In the region above 1 kHz,the increase of IR with raising frequency becomes quicker and tgδ-f dependence tends to be steady.This suggests that IR be dominanted by absorption current relative to polarization of dielectric.This region can be called absorption current region.In this region dielectric loss increases rapidly and luminescence efficiency is on the decrease.106|50|0更新时间：2020-08-11
- 摘要：Fluorescence spectra for 7,8 dihydroxy-4-methyl coumarin and its copolymers in solid state have been recorded,with and without pre-treatment.An emission at 420nm is observed in all the above specimens.This is interpreted on the basis of the attachment of groups in various positions in the monomer and the conversion of hydroxyl group into ester group during pilym:vization.The intensity is explained on the basis of various dibasic acid links.113|177|0更新时间：2020-08-11
- 摘要：Present paper covers a simple HWE apparatus and the technique to grow PbTe(111)single crystal film on BaF2(111)substrate by HWE,and the discussion of growing mechanism,104|110|2更新时间：2020-08-11
- 摘要：The study of chemiluminescence(CL)reaction of lucigenin-H2O2-ClO- system and the sensitization of acetone is reported.In basic medium,the ability of H2O2-ClO- is greater than that of H2O2 or ClO-.Thus,H2O2-ClO- can quickly oxidize lucigenin and the CL intensity is increased.Acetone can increase the speed of CL reaction of lucigenin-H2O2-ClO- system and enhance the CL efficiency of above CL reaction,therefore,can raise the CL intensity.The sensitized CL intensity is proportional to the concentration of ClO- in the range of 1.25×10-9g/ml-2-2.0×10-4/ml.Many foreign ions do not interfere with the determination of CLO-,Based on these results,we have developed a novel CL method for the determination of trace ClO-,The detection limit of the method is 0.25ng/ml.101|97|0更新时间：2020-08-11
- 摘要：A new luminol electrogenerated chemiluminescence flow system is described.In order to maintain the required pH condition for luminol chemiluminescence,H2O2 was reduced into OH- through a flow cell containing two micro Pt electrodes.Preliminary studies of the luminol chemilumines-cent mechanism were carried out and the electrogenerated chemiluminescence conditions were optimized.The system obviously had lower noise than that in mixing reaction system.The described system can be used as an indirect detector in liquid chrornatography.106|62|1更新时间：2020-08-11
- 摘要：Concanavalin A-induced chemiluminescence of the lymphocytes in sheep lung lymph was studied.The results indicate that determination of lymphocyte chemiluminescence has advantages of rapidity,simplicity and sensi-tivity and can be served as a method for determination of lymphocyte activity.The ideal determination system consisted of 1 ml of lymphocytic suspension(106-107 cells/ml),0.1 ml of Con-A solution(2mg/ml)and 50μl of luminol solution(10-3M).Polymorphonuclear leukocytes could enhance the chemiluminescence intensity of the system.So,purification of cells should not be ignored when the lymphocytes in peripheral blood were determined.Inhibition of the chemiluminescence by indomethacin suggested that the chemiluminescence of lymphocytes might related with the metabolism of arachidonic acid.95|56|1更新时间：2020-08-11
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