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摘要：Three kinds of transparent resins were prepared by three different synthesis methods. Sample 1 is transparent resins formed by RE(MA)₃ salt polymerizing,Sample 2 is transparent resins containing rare earth(RE) complexes by doping method,and Sample 3 is transparent resins containing rare earth complexes by in situ compo-site method. The transparent resins were characterized by TGA,impact energy,UV-Vis,FT-IR ,¹H-NMR and fluorescence spectra. The fluorescence data indicated that the optical resins display intense and narrow-band emission,highly visible transparency,and good mechanics performance in Sample 2 and Sample 3. The photoluminescence intensity enhanced and lifetitne is raised in doping or in situ method after introducing RE complexes into copolymer system,by comparing with RE complexes powder. The fluorescence data revealed that the fluorescence intensity of Sample 3,which synthesized by in situ method,is the strongest among the three samples. It was revealed that the in situ synthesis method,as a novel method,can be quickly and simply employed to synthesize transparent optical resins. Comparing with the resins by doping method,these composite resins possess better luminescent property at the same RE concentration.  

摘要：LED is one of the green light sources in the 21st century, and it has broad prospects in the illumination. In recent years, there have been more and more LED lamps, and designing appropriate LED lamps become very important. The power of a single LED is very small, but lighting requires the uniform flux and illuminance in a certain region, so it is necessary to use LED arrays for increasing the brightness and luminous area, improving the uniformity of illuminance. This paper calculated illuminance of the LED arrays at first, and then according to known functions, the LED arrays were simulated and analyzed. The distribution characteristics of the different LED arrays were obtained by comparing the characteristics of two kinds of LED arrays. Finally, the law of arrays suiting lamps was shown, which will be able to provide the accurate reference for designing LED lamps.  

摘要：In this paper, the absorption property of the left-handed material (LHM) rectangular waveguide was studied by use of the perturbation method, and other novel properties were revealed. Due to the restriction of the dispersion equations, the LHM waveguide can not support the fundamental modes, and its absorption property is quite different from that of RHM (right-handed material) rectangular waveguide. It was shown that E^y₁₁ mode's attenuation coefficient changes from large to small as the length to width ratio (a/b) grows, while the result is reverse in RHM rectangular waveguide. In addition, when different modes are propagating in the same LHM waveguide there is an absorption peak for every mode, and in a small neighborhood of this peak, an attenuation trough can be found. In this case, higher-order modes possess larger attenuation coefficient than lower-order modes. But, when different modes are propagating in the RHM waveguide the attenuation curves are changing vibrantly and approach the core attenuation coefficient with the increasing of the width b. Otherwise, higher-order modes possess smaller attenuation coefficients than lower-order modes in RHM waveguide.  

摘要：The differential cross-section (DCS) for electron Raman scattering (ERS) in a semiconductor spherical quantum dots was presented. The process of ERS neglects the phonon-assisted transcription and the electron states were confined with GaAs or CdS quantum dot system. Single parabolic conduction and valence bands were assumed. The contribution caused by electron and hole was contrasted separately. The selection rules for the process were also studied. Singularities in the spectra are interpreted for various quantum sizes and different incident photon energies.  

摘要：The excitons in the spherical semiconductor core-shell quantum dots embedded in an insulator matrix were studied theoretically in a simplified model within the framework of effective mass approximation by using the variational approach. The calculations for the values of the wave functions as functions of coordinate, and the critical potential as functions of the ratio of shell width to core radius were performed numerically, respectively. It was found that there exists a critical potential for a given ratio of the shell width to core radius, when the potential decreases cross this critical value the exciton transforms from a type- Ⅱ exciton into a type- Ⅰ exciton. For a given potential, there exists a critical ratio of the shell width to core radius, when this ratio decreases cross this critical value the exciton transforms from a type- Ⅱ exciton into a type- Ⅰ exciton. The essential features were clarified, which may serve as a starting point for the analysis of excitons in real materials.  

摘要：The study of the rare earth complexes has been an active research area, which may be attributed to the specific spectroscopic and magnetic properties of rare earth ions and the abundance of rare earth elements in our country. Amide-type ligands which are flexible in structure and have 'terminal-group effects', will shield the encapsulated rare earth ion from interaction with the surroundings effectively, and thus achieve strong luminescent properties. Aiming at good fluorescent rare earth complexes, a new diamide ligand 1,4-bis benzene (L) and its Sm(Ⅲ), Eu(Ⅲ) and Tb(Ⅲ) complexes were synthesized for the first time. The analytical data indicated that the three rare earth complexes conform to a 1 : 1 metal-to-ligand stoichiometries Ln(NO₃)₃·L. The IR spectra show that the three complexes have similar IR spectra, of which the characteristic bands have similar shifts, suggesting that they have a similar coordination structure. The fluorescence properties of the ligand and its rare earth complexes were investigated in detail on Hitachi F-4500 spectrophotometer. The results indicated that the Sm, Eu and Tb complexes exhibit the characteristic emissions of Sm³⁺, Eu³⁺ and Tb³⁺, respectively. The fluorescence of the ligand and Sm, Eu complex is weak and the Eu³⁺ is not in a centro-symmetric coordination site. The Tb complex shows strong fluorescence, which could demonstrate the ligand L is a good organic chelator for Tb³⁺.  

摘要：Vertical cavity surface emitting lasers (VCSEL's) are widely used in optical communication due to their single-longitudinal-mode operation, circular output beams, suitability for monolithic two-dimensional (2-D) integration, and compatibility with on-wafer probe testing. In recent years high power output has been realized by increasing the size of the emission window or by high densely integrating VCSEL array. Accom- panying the increase of the output power, the performances such as temperature stability, conversion efficiency, and mode distribution are often deteriorated by the non-uniform distribution of carriers across the active region and the self-heating inside the device.Self-heating results in considerable differences between the operating performances under continuous wave and pulsed operation. Thermal roll-over of the output power with current is observed under continuous wave, which limits on the further increase of lasing power.A theoretical model based on laser rate equation is presented to simulate the output performance of high power VCSEL. In this simulation, thermal offset current is introduced to compensate the threshold current between room temperature and operating current. Thermal characteristics parameter is obtained from the depen-dence of the output power on the current at different temperature. Other parameters are extracted using the method of Gao et al. The dependence of P and I at certain ambient temperature was calculated according to the model parameters, and it shows a good consistent between the theoretical and the experimental results in the temperature range from room temperature to 100 ℃. In addition, the relationship between temperature and current indicates sever temperature increase in the active region.  

摘要：A simple and sensitive sequential injection procedure coupled with chemiluminescence detection was developed for the determination of formaldehyde in air, which was based on the chemiluminescence reaction of formaldehyde, gallic acid and hydrogen peroxide in an alkaline media. The experimental parameters affecting the analytical sensitivity were optimized. Under the optimized condition, the chemiluminescence intensity changes linearly with the concentration of formaldehyde over the range of 1.0×10^-7~2.0×10^-3 mol/L, with a correlation coefficient of 0.999 3. The relative standard deviations of the method for 1.0×10^-6 mol/L formaldehyde was 2.1% (n=11). The detection limit was 5.0×10^-8 mol/L and sample throughput was 140 samples per hour. Good recoveries were obtained for spiked samples, and the results achieved were in good agreement with the certified values for standard reference material. The proposed method has several merits including sensitivity, automation, simplicity, less reagent consumption and waste generation and has been applied for the measurement of formaldehyde content in air.  

摘要：In order to optimize the Al composition of the barrier in GaN-based quantum cascade laser, we made a self-consistent calculation to the Schrdinger and Poisson equations of one period of barrier in QCL. The band structure and the electron envelope function were obtained. The relation between dipole matrix element and Al composition of the barrier was illuminated. The results showed that the dipole matrix element is the largest for the optimized Al composition to be 0.15.  

摘要：Recently, lanthanide-based nanocrystals have showed great potential to be used as luminescent materials, considering their attractive optical and chemical features such as low toxicity, large effective Stokes shift and photochemical degradation. In this paper, we developed a simple method to prepare PEI coated CeF₃ : Tb³⁺ nanocomposites in aqueous solution. The samples were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectra. The results show that all the prepared nanocrystals are hexagonal shaped with an average size at around 10 nm and can also be used for covalently bonding to biomolecules.The products exhibit excellent green fluorescence under UV excitation. Further, the photoluminescence intensity is increased with the increasing doping concentration of the Tb³⁺ and reached a maximum at approximately 20%.  

摘要：In this article, a new thiocyanate sensor NNN based on naphthalimide was conveniently synthesized using a simple method, and all the reactions were taken at room temperature. The determination process can be taken out in water and has no interference by any other anions. NNN has large Stocks shift about 100~140 nm in different solvent, and high quantum yield about 0.6 in polar solvent. With the addition of SCN^-, the absorption peak of NNN at 417 nm decreases, at the same time a new absorption peak appears at 347 nm, when the concentration of SCN^- is up to 1 mmol/L, the peak at 417 nm is disappeared. The absorption wavelength has a blue-shift of 60 nm, the colour of the solution changes from yellow to colorless. This obvious difference in colour is easy to observe by naked eyes. The ratio of two peak values on absorption spectra is linearly related to the concentration of the SCN^- in a large range (20 μmol/L ~0.8 mmol/L), this result makes the quantitative analysis of SCN^- realizable. The fluorescence of NNN is quenched by the SCN^-, the fluorescence quantum yield decreases from 0.33 to 0.02, there is no other anions to interference the detection.  

摘要：For doing the best to improve the ratio of the transformation from electronic power to luminous energy and efficiency of heat dissipation for the luminous board of the high power bright white LED street lamp, the method to extend area of LED chip was adopted and don't decrease LED's external quantum efficiency when LED chip was designed and made. The technology of optimizing was adopted for increasing luminous quantity, and let LED chip's heat distribute on the LED chips surface averagely and make LED chip work in stable status. The integrated technology was analyzed to enhance efficiency of geting light and assure the quality of white bright emission by LED device and heat dissipation of LED device. The best technology, which was adopted to array matrix of LED chips of luminous board with high power bright white LED for street lamp, is COB (chip on board) technology, and according to the technology result,the thermal resistance of the packaging solution for high power bright white LED chip was analyzed by Finite Element Analysis Software.The technology of COB makes LED devices temperature easyly to be controlled below 120 ℃ when it is electrified, and it is easier for COB to compatible with external cooling devices. The optimum distance of the LED chips of the luminous board with high power bright white LED for street lamp was figured out by the formula to make bright to be best normalized. The best optimum driving scheme for high power white bright LED street lamp was defined, that LED street lamp must be drived by constant current and the brightness of the street lamp was regulated by the PWM technology at last.  

摘要：Well-crystalline ZnO nanorods were synthesized by employing zinc acetate dihydrate and hydrazine hydrate as reactants without using any surfactant. The phase structure, morphology and optical properties of the product were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM) and room-temperature photoluminescence (PL) spectrum. The results demonstrated that the well-dispersed wurtzite ZnO nanorods have an average diameter of 120 nm. The ZnO nanorods prepared by this simple solution method have a strong emission peak at 386 nm with a full-width at half maximum of 18 nm, and a wide emission band in the visible range. Without using any surfactant, microreactors for the nucleation and growth of ZnO nanorods were supplied by adjusting the ratio of the mixed solvents.  

摘要：In all-optical networks, distributed algorithms for attack localization was analyzed, and an all-optical network simulation platform was constructed for attack localization and resumption. For a single point of attack, the experiment showed that the distributed algorithm for attack localization can find the source of attacks, which is caused by "rampant attacks" of the transparency of the optical network. On the basis of this, automatic protection switching and loopback are restored quickly.  

摘要：Considering the growing importance of energy saving and environmental friendliness, solid-state lighting is emerging as a highly competent field and a possible alternative to existing lighting technologies. Recently, a blue LED combining with a yellow emitting YAG ∶ Ce phosphor was used mostly to make white-lighting LED, however, as the high synthesis temperature of YAG phosphor, poor color quality due to the serious scarcity of red light, a novel phosphor is rather needed. An Eu-activated silicate-based phosphor for WLED was prepared by solid-state reaction (SSR) under reductive atmosphere. The morphology of the phosphor powder was observed by means of scanning electronic microscope. The excitation and emission spectra were measured by F-4500 spectrometer using a Xe-lamp as an excitation source. And the encapsulation cha-racteristics of silicate-based phosphor were comparatively studied with that of YAG phosphor. The results showed that the as-synthesized silicate-based phosphor has homogenous particle size of about 15 μm and broad excitation band. When the as-synthesized phosphor and YAG were encapsulated to blue LED chips with diffe-rent emission wavelength, the chromaticity coordinate, color-rendering index and luminous efficiency fluctuated a little; especially the luminous efficiency only fluctuated about 5% in comparison with YAG. However, when YAG phosphor was encapsulated to blue LED chip with emission wavelength longer than 462.5 nm, its luminous efficiency decrease remarkably due to its narrow excitation spectra. The comparison results of relative emission spectra of silicate and YAG LED indicated silicate phosphor is more suitable for the encapsulation of warm white LED than YAG phosphor. And the results of particle size showed silicate phosphor have potential application for high power LED. The aging performance of silicate phosphor is better than that of YAG phosphor. In conclusion, the as-synthesized silicate-based phosphor is a novel phosphor for white LED, having a broad excitation band and excellent chemistry performance, especially well matched with blue-light-emitting LED chips with different emission wavelengths.  

摘要：The study on measuring system of LED characteristics based on the high-level image programming language(LabVIEW) was described in this disquisition. The measuring system was designed based on removable guideway, multi-testing locations and computer control, making the comprehensive LED-light-source pro-perties including electrical,photometric and colorimetric characteristics be measured automatically and conti-nuously. This measuring system displays some remarkable merits, such as synthesis,automatization,intergration,continuity and on-line and is further able to improve the efficiency of testing,reliability and accuracy of testing data, results, solving the shortcomings of traditional test methods,such as scattered, low efficiency and high-test errors. The study also introduced design principles of the self-developed system software and elaborated on how to realize the function including the collection of test data, calculation, analysis treatment, etc based on LabVIEW in this measuring system with emphasis. Interrelated experiment data is also attached for demonstrated farther for measuring system.  

摘要：The electronic and optical properties of blende phase ZnS systems doped with 3d transition metal ions were studied by the first-principles method based on density functional theory. The density of state, band structure, and absorption coefficient were calculated. The obtained results indicated that the bottom of the valence band and the conduction band of all the doped systems shift to the low-energy area compared with that of pure ZnS, and the band gap reduces. The dopings of Fe, Mn, Cr, and V are the n-type dopings, and the doping of Cu, Ni, Co are the p-type doping. Absorption edges of all the doped systems shift obviously to the infrared region; there is strong absorption in the green light distinct for all the systems. Furthermore, there is strong absorption in the far ultraviolet region for V and Cr doped systems. Our results are in agreement with experiments.  

摘要：An exploration by a parametric X-ray radiation,channeling radiation and crystalline Undulator radiation as a new light source has given rise to extensive attention. The particle motion must be stable in order to obtain these sources. But, because the radiation damp,the vibration of lattice,the electron multi-scattering and non-linearity of interaction potential of a particle with crystal,the instabilities by the dechanneling,birfucation and chaos exists in the system,thus the reflaction,the diffraction,the focus and the spectral distribution of these radiations will be effected.The effects of the stabilities by a bifurcationc of the rotated periodic orbit is regarded specifically in the paper. In the classical mechanics frame and the dipole approximation the particle motion equation is reduced to the generalized pendulum equation with a dampping,a force terms and the constant moment by the sine-squared potential.The solution of the equation and the period of the particle motion for a non-pertubated system are expressed exactly by means of Jacobian elliptic function and the 1-st kind elliptic integral.Melnikov function of the rotated periodic orbit is constructed,and also bifurcation of the system is analyzed by the method.It was shown that the critical condition of the system entered in a birfurcation is related to its parameters, provided regulating a parameters of the system,the birfurcation (an instability) can be avoided in principle.Thus, the effective export of the coherent,channeling radiation and crystalline undulator radiation can be assured furtherlly.  

摘要：In recent years, with the development of semiconductor growth technology, people have producedsome kinds of quantum dots. The novel optoelectronic properties and the transport characteristics of quantum dots will be a widely applied prospect.The interaction of of the electrons with longitudinal-optical(LO) phonons in quantum dot have attracted more physicists because of the electronic properties of particular importance.The more physicists have studied the polaron in quantum dots by a lot of method. The properties of bound polaron in a parabolic quantum dot have been discussed using the linear combination operator and the unitary transformation method by the present authors. However, using Huybrechts method, the properties of the excited state of polaron in a quantum dot has not been investigated so far. In this paper, the ground-state energy, the first excited-state-energy,the transition energy from first excited -state to ground-state and transition frequency were derived by using the Huybrechts method. Two limiting cases were discussed. Firstly, we investigated the transition energy and the transition frequency of the weak-coupling polaron in a semiconductor quantum dot.The numerical results showed that the transition energy and the transition frequency increases with decreasing the effective confinement length.Secondly, we investigated the transition energy and the transition frequency of the strong-coupling polaron in a semiconductor quantum dot. The numerical results showed that the transition energy and the transition frequency increases with decreasing the effective confinement length of quantum dot .The transition energy and the transition frequency of weak- and strong-coupling polaron in a semiconductor quantum dot decreases with increasing the electron-phonon coupling strength.  

摘要：Semiconductor structures with quantum confinement have shown interesting behavior. In recent years, the physical properties of quantum heterostructures composed of the group-III nitrides semiconductors with wide-band-gaps, such as AlN, GaN and InN, as well as their ternary compounds, have been widely stu-died arising from their promising application in short-wavelength electroluminescence devices.The high pressure, high electric-field, intense magnetic-field become the powerful tools to explore the property of material. Some authors investigated the effects of electric field and hydrostatic pressure on donor binding energies in a GaAs quantum dot. Some authors calculated the ground-state binding energies for a hydrogenic impurity in a spherical quantum dot within a uniform magnetic field. How ever, However,few studies focused interface effect and hydrostatic pressure on zinc-blende nitride quantum dots. As the periodicity of the host semiconductor is lost, or when the impurity potential varies too rapidly over an effective Bohr radius the effective mass approximation is not reliable.In the present work, a modified variational method within the simplified coherent potential approximate was adopted to investigate the impurity state binding energies of GaN/Ga_1-xAl_</em>xN infinite barrier spherical shape quantum dot by using a triangular potential to approximate the interface potential. Considering the hydrostatic pressure and a position dependent mass, the relations among the impurity binding energies, the hydrostatic pressure, quantum dot radius and the electron areal density were calculated. The result indicated that the binding energies of impurity state nearly linearly increase with pressure. It also showed that the influence of conductive band bending and the position dependent effective mass should not be neglected. As the quantum dot radius is smaller, the binding energies are not affected by conductive band bending. With the increasing of the quantum dot size, the binding energies increase gradually with it. For a given hydrostatic pressure and Al component, the electron areal density n_s strengthens the band bending of the interface to increase the binding energy.  

摘要：The effect of the electron-phonon interaction on the quadratic electro-optic effect(QEOE) and electro-absorption process (EA) was investigated theoretically for electrons confined in a core-shell quantum dot. The interactions of electrons with different phonon modes in the core-shell system, including the confined longitudinal optical (LO) and the interface optical (IO) phonon modes, were investigated. We carried out a detailed calculation of quadratic electro-optic effects(QEOE)and electro-absorption process(EA) on a ZnS/CdSe core-shell quantum dot as a function of pump photon energy with different incident photon energy and under different quantum dot size. The results revealed that the polaron effects are quite important especially around the peak value of the third-order susceptibility.  

摘要：A kind of low-dimensional structure on SiGe alloy film can be formed by laser irradiation (75 W power and 1 064 nm wavelength) and high temperature oxidation, and the low-dimensional structure can emit intense photoluminescence (PL). A emission model of three-level system in the interface between SiO₂ and Ge crystal cluster is proposed for interpreting the PL peaks at 705 nm and 606 nm. The results in this article indicated that the band gap of Ge nanocrystals opens by quantum confinement. The emission energy increases with decreasing sizes, distributing the band PL spectra. A sharp PL emission takes place at 606 nm, which is independent of size. In this process, the photo-excitation occurs in germanium nanocrystal while the photo-emission occurs in oxide interface. It is demonstrated that population inversion between the top state of the valence band and the trap state in the nanocrystal-oxide interlayer is possible.  

摘要：Delayed luminescence(DL) of bioluminescence is the important content of optic-biology in biophysics. Since 1923, a lot of research has been carried out. In this paper,we choose the lotus leaf as the test materials to experiment. The curve of delayed luminescence with different treating time under different concentrations of NaCl,the changing curve of initial intensity of delayed luminescence with different treating time and the changing curve of attenuation parameters of delayed luminescence with different treating time were researched by BPCL instrument. The results indicated that, with the stress time increasing, the initial strength and attenuation parameters of DL with 0%,0.01% and 0.10％treatment firstly increased and then decreased; the initial strength and attenuation parameters of DL of 1.00% and 5.00％treatment decreased all along; the initial strength and attenuation parameters of DL of 10.00% and 20.00％treatment decreased to a low-level from the jump; on the whole, 0.10% NaCl treatment had the lowest effect on the initial strength and attenuation parameters of DL. The experiments showed that the DL can reflect the level of injury of salt stress on leaves. The conclusions of the biophysical methods for measuring the outside world impact of stress on the blades can provide a certain reference value.  

摘要：The UV-Vis absorption spectra, steady-state fluorescence spectra and the fluorescence decay curve of 4-(notro)-4'-(amido)-azobenzene (NAA) in chloroform solution were measured. The photoinduced color changing phenomena were investigated. The transition energies and the excited state lifetime were observed. It was found that the reaction of NAA photochemical Cis-tran-isomerization is not a first-order reaction, and it is very complex. The transition energies for trans-and cis-isomers are 255.6 kJ/mol and 240.2 kJ/mol. The excited state lifetimes for trans- and cis- isomers are 0.02 ns and 3.54 ns. And it is influenced by the content of trans- and cis- isomers and the interacting of NAA molecule to NAA molecule or to the solvent molecule.  

摘要：A series of luminosilicate glass samples doped with Eu²⁺ and Dy³⁺ were prepared under reducing atmosphere. The impacts of temperatures on luminescence performances of long-lasting afterglow glass were analyzed. The time-integrated intensities of afterglow in SrAl₂O₄ : Eu and SrAl₂O₄ : Eu,Dy long-lasting afterglow glasses were compared. Results showed the emission spectra have two broad bands peaked at 455 and 515 nm and the afterglow decay is in proportion to t^-0.8. The time-integrated intensity of afterglow increases at around the temperature of 150 K, and reaches the maximum at around 275 K. The hole traps originate from Dy³⁺ ions.  

摘要：Mg_xZn_1-xO films were deposited by metalorganic chemical vapor deposition (MOCVD) on sapphire substrate (1120). Optical properties were investigated at different Mg concentration. The photoluminescence decay curves of the films with different Mg contents at 77 K were carried out. It was found that exciton lifetimes of the films become longer with increasing Mg content. For a film with Mg concentration of 50%, the exciton lifetime is 872 ps.