最新刊期
卷 6 ， 期 4 ， 1985
- 摘要：Nine lectures en Franck-Condom aspects of multiphoron transitions were given at the Changchun Institute cf Physics，Academia Sinica, from 25 July to 5 August 1985.106|64|0更新时间：2020-08-11
- 摘要：A surface polariton is the electromagnetic wave localized at the surface of the medium coupled to an elementary excitation of a condensed medium. The detailed study of surface polariton gives information about optical properties of semiconductors. In this paper, the effect of lattice vibration on the dispersive properties of the coupled system of surface electromagnetic wave and exciton is studied. The dispersion relations of the coupled system are obtained.114|42|0更新时间：2020-08-11
- 摘要：Recently, there present many works to discuss the phase transition-like behaviour of the polaron in polar crystals. However, all these works didn't consider the incorporate effect of the temperature and electron-phonon Frohlich Coupling constant r. In this paper, starting from the Bogolyubov inequality for the free energy, we discuss this incorporate effect on the phase transition-like behaviour of the polaron.The Hamiltonian of a system consisting of the electrons and phonons is shown as (2.1) in the text. And assume that the Bogolyubov ineqality between the real free energy F(H) and the model free energy Fmod(H) also holds for the polaron. The Bogolyubov ineqality has the form (2.4) in the text. In this representation, H can be regarded as the sum of H0 and a perturbed term (H-H0). H0 is represented [by (2.8) which is called the model Hamiltonian. In the course of calculation, we introduce two unitary transformations U1 and U2. Then, applying these transformations to (2.4), we finally obtain the expression (2.27) from which the free energy can be determinded. Lagrange multiplier u in (2.27) has the meaning of the translation velocity of the polaron. The effective mass of the polaron and the mean numbers of phonons N in the cloud around the electron are, respectively, represented by (3.5) and (3.6). The expectation value of the polaron energy with respect to the ground state |0> at the different temperature is expressed by (3.4).123|57|0更新时间：2020-08-11
- 摘要：In this paper, we studied behaviors of the exciton near the interface by means of the unitary transformation method.Suppose a piece of polar crystal filled the space of z>0 and another piece of non-polar material contacted with it at z=0. Assume that the exciton might be rgarded as an interaction of a surface electron polaron with a hole polaron, and there was an interaction between the exciton and the phonons.122|56|0更新时间：2020-08-11
- 摘要：We have systematically studied the interaction between Ce3+ and Tb3+ ions in LaOBr: Ce3+, Tb3+. We have measured emission spectra of a series of samples with the model MPF-4 spectrometer.The excitation wavelength is 337nm.The emission spectra of LaOBr:Tb3+ consist of the 5D3-7FJ and 5D4-7FJ (J=0,1, 2,…, 6) transitions. The main characteristic lines in these two groups are 5D3-7FJ (415.9nm, 436.6nm) and 5D4-7FJ (485.4nm, 543.1nm) transitions. In the emission spectra of the LaOBr: Ce3+, Tb3+ there are not only the emission band of the Ce3+, but also the 5D3-7FJ and 5D4-7FJ transitions of the Tb3+ ion when xce≤3×10-4. But the emission intensity of the Tb3+ ion is about 15-25 times higher than that of the sample without Ce3+ ion.The emission spectra of the LaOBr:Ce3+,Tb3+ consist of the emission band of the Ce3+ ion and the emission lines of the Tb3+ ion, which is only 5D4-7FJ when xCe>3×10-3. The emission intensity of the Tb3+ ion (5D4-7FJ) increases with the increasing Ce3+ concentration.116|36|0更新时间：2020-08-11
- 摘要：There has been considerable interest in blue electroluminescence (EL) in ZnSe diodes recently[1-3]. In our earlier work,the attention was directed to the determination of the origin of the blue emission spectrum at room tem-peratature[4,5] and the improvement of the spatial distribution of blue EL in ZnSe MIS diodes[6].The study of the blue EL in ZnSe focused on bulk crystals by sublimation and other methods at high temperature.The as-grown ZnSe crystals usually contained a large number of intrinsic defects, and had high resistivity even if donor impurities had been dopped.So far,many papers reported on thin epitaxial films of ZnSe grown by MOCVD[7,8],MBE[9,10],LPE[11,12] and VPE[13-16],and high quality ZnSe epilayers were grown.However there were a few reports[17,18] on preparing blue EL in ZnSe MIS diodes using the ZnSe epilayers. In the present paper we first reported the blue EL at room temperature from the vapor phase epitaxial ZnSe grown on GaAs.101|60|0更新时间：2020-08-11
- 摘要：This paper is a continuation of the research on the luminescence of Eu2+ ions in MFX matrices and their systems, where M represents alkaline earth metal ions and X, nonfluorine halide ions. The emission spectra ard the relative emission intensities of Eu2+ ions in the systems BaFCl1-xIx and BaFCl1-xIx under the excitation of X-ray, cathode ray and ultra-violet light have been investigated. The change of the energy levels of excited 4f65d state of Eu2+ with the composition of these systems is discussed.102|20|0更新时间：2020-08-11
- 摘要：In this paper, the preparation method, and the luminescence properties of phosphors with formula M3La2(BO3)4:Eu3+ (M=Ca,Sr,Ba) are reported, and the relation between the spectra and the crystal structure is discussed.Samples were prepared by firing mixtures of MCO3, La2O3, Eu2O3 and H3BO3 at 700℃ for 4 hours and then at 1180℃ for 8 hours. It was necessary to grind the samples and mix them fully again between the two firing stages.99|33|0更新时间：2020-08-11
- 摘要：The software design for multifunction,color-variable LED matrix display controlled by a single board computer is described. The software not only can be used in the multifuction color-variable display of the LED matrix,but also can be used in the powder EL, thin film EL and other matrix displays. Using the program depicted in this paper, it is able to display alphanumeric digit, graphs and lines with three colors of the red, green and yellow.The multifuction color-variable display device having 16×50 picture elements is controlled by a TP-801B single board computer. The element of the matrix panel consists of the double-color LEDs. With the aid of a suitable hardware interface circuit, the characters or graphs, which are to be displayed, are stored into the memory of the computer and the display is controlled by the dynamic scanning program. The display has advantages of low power dissipation, low cost, high level of integration and high stability. Especially, its color, display contents and operation mode can be controlled with great ease. It can be widely used in subway stations and airports as the place name and time display, and in gymnasium and stadiums as the score display. It can also serve as the display terminal of military command systems.According to the software design Z-80 assembler language was used to make the program. The program was debugged and optimized, and then was writted into the EPROM.All the desired results have been achieved.105|54|0更新时间：2020-08-11
- 摘要：Currently, methods of utilizing fluorescence in the diagnosis of cancers are roughly divided into two kinds: The method of fluorescence sensibilization and the method of direct observation of the inherent fluorescence. This paper reported the study of the electronic spectrum of the tissue homogenate of human stomach,and quantitatively investigated the center of luminescence. According to the observation of the inherent fluorescence, an early diagnosis of malignant tumors may be made preliminarily.The tissue homogenate of human stomach has a relatively strong photoabsorption in near ultraviolet and violet areas. The photoatosorption in violet area is the absorption of the purine compound in biologic tissues. It is evident that the electronic spectrum is influenced by the transition of the leading conjugated π electrons.It is obvious from the results of the experiment that utilizing ultraviolet light with different wave lengths to excite the gastric homogenate, roughly same integrated protein fluorescence emission peaks were obtained. Comparing this emission peak with that of the tryptophan (348nm), some displacement was found, and this is just the fluorescence characteristic of the protein B. Therefore, it is concluded that under the excitation of ultraviolet light, the photospectrum of aromatic compound is the chief characteristic of that of the gastric homogenate.From the result of the experiment, it is noticed that the emission in red area of the ultraviolet-excited gastric homogenate was basically originated from the transition of the ρ electrons of purine cyclic group of hemoglobin. It possesses distinct common characteristics with ths fluorescence spectrum of the human whole blood, hemoglobin and hematoporphyrin. Therefore, the photoemission of gastric homogenate in visible area was chiefly originated from the hemoglobin molecules of the tissues.Once the pathologic lesions developed in tissues, it will inevitably lead to changes in the molecular composition, molecular structure as well as physicochemical environment around the emission center, eausing changes in the state of emission center as a result of changes in inherent fluorescence. In the comparison of the spectrum of inherent fluorescence in normal tissue with that in cancer tissues, it is obvious that there is significant difference between the emission peak of the fluorescence of cancer tissues and that of the normal tissue homogenate.122|51|0更新时间：2020-08-11
- 摘要：The blockdiagram of the weak spectral measurement system developed in our group is shown in Fig.1. The luminescence of a sample is excited by a laser, and dispersed through a spectrometer to become spectral signal. The weak, spectral signals are first intensified by an image intensifier and then picked up by a TV camera to convert into video signal. The TV picture of the video signal corresponds to the spectral. The signal of each channal is integrated along the direction of spectrum fringe to increase signal-to-noise ratio. The data converted by A/D converter enter microcomputer system and are processed according to the reguirement of each operational function. Finally a CRT displays the spectral curve as well as the relative character comments. At the same time, a plotter can draw spectral curve and a printer can give all the data required by user. According to a laser power monitor, the microcomputer only collects the spectral data within the range of predetermined power, or classifies the spectral data with laser power. Spectral curves with different excitation density are then displayed.103|66|0更新时间：2020-08-11
- 摘要：This paper gives an outline of the results in the study of powder DCEL in our lab. The development of phosphor and device, and the advances in the investigation of DCEL mechanism are described, including the methods of preparation techniques for phosphor, copper-coating, ZnS raw material, binder, and forming process, the mechanism of DCEL, and so on.Some applications of powder DCEL are also described briefly.121|54|0更新时间：2020-08-11
- 摘要：This paper introduces briefly the properties of HgCdTe and the progress in its applications and preparation. The applications to infrared detector are emphasized. A comparison of various technology and methods for growth of HgCdTe crystal is given. The sliding liquid phase epitaxial (LPE) growth of HgCdTe thin film is described in detail.114|188|0更新时间：2020-08-11
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