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991.
A new organic compound of bis-glycine maleate was synthesized in the alkaline medium of 10% ammonium hydroxide solution. The bulk single crystals of Bis-Glycine Maleate (BGM) have been grown by slow cooling method. The grown crystals were characterized by employing single crystal and powder X-ray diffraction, Fourier transform infrared, optical absorption spectral studies and thermo gravimetric analysis. The microhardness studies confirmed that the BGM has a fairly high Vicker’s hardness number value (41 kg mm−2) in comparison to other organic NLO crystals. Second harmonic generation efficiency of the crystal measured by Kurtz–Perry powder method using Nd:YAG laser is found to be comparable to that of potassium dihydrogen phosphate (KDP). Frequency dependent dielectric studies were carried out along the major growth axis. 相似文献
992.
Xue-Chao Liu Zhi-Zhan Chen Bo-Yuan Chen Er-Wei Shi Da-Qian Liao 《Journal of Crystal Growth》2010,312(20):2871-2875
The Ga-doped and (Ga, Co)-codoped ZnO films were grown on quartz glass substrate by inductively coupled plasma enhanced physical vapor deposition. The effect of Co doping and oxygen pressure on the structural, optical, electrical and magnetic properties of the as-grown films was investigated. The structural characterization revealed that high-quality films were grown with wurtzite structure and c-axis preferred crystalline orientation. The surface morphology was affected by Co doping and oxygen pressure. Room-temperature ferromagnetism was observed in (Ga, Co)-codoped ZnO films. We found that the optical and electrical properties were degraded with Co doping. The Ga-doped ZnO films had an average transmittance of above 88% in the visible wavelength, while (Ga, Co)-codoped ZnO showed a lower average transmittance (∼65%) due to the d-d transitions of Co2+. The resistivity and Hall mobility of (Ga, Co)-doped ZnO samples were lower than those of Ga-doped ZnO films when grown at the same oxygen pressure. 相似文献
993.
994.
995.
Conjugatedpolymerswithlargethird-orderopticalnonlinearityhavebeedfocusedfortheirpromisingpotentialsforadvancedmaterialsapplications'.Recently,investigationsoftransitionmetalwithorganicligandsystemshavebeengreatlyintensifiedduetothedelectronsincorporatedintheconjugatedsystem,whichareexpectedtoellhancethehyperpolarizability.Phenylacetyleneandthemetalphenylacetylidesplayimportantrolesinformationofuniquecoordinatedc-lusters',butitseamsthatthestudyofmetalphenylacetylides,particularlyofthesilverphen… 相似文献
996.
分析得到了横向电场分量和磁场分量所满足的耦合方程,对于介质折射率的不连续处,采用严格的边界条件来处理。基于全矢量模型,使用有限差分法编写了复模式的求解器,并将其应用于Bragg光纤的模式求解和分析。绘制出了Bragg光纤模式谱图,分类分析了在无限包层情况下Bragg光纤模式的基本特性。 相似文献
997.
C. Fitzpatrick E. Lewis A. Al-Shamma’a I. Pandithas J. Cullen J. Lucas 《Optical Review》2001,8(6):459-462
Low-pressure mercury lamps are commonly used for germicidal applications such as water and wastewater sterilisation. The germicidal
effect is due to the emission of light at 254 nm, which leads to the destruction of most waterborne bacteria. The Microwave
plasma ultraviolet lamp (MPUVL) is a new technology for generating a high intensity ultraviolet (UV) light. A Fluorescent
optical fiber based sensor is presented which is used for monitoring the output of a high power microwave UV light source
and its control. This sensor is a fiber which has had its cladding removed and been coated with a phosphor doped polymer.
This paper was originally presented at the 2001 International Conference (2nd Joint OSJ-SPIE Conference) on Optical Engineering
for Sensing and Nanotechnology, ICOSN 2001 which was held June 6–8, 2001 at the Pacifico-Yokohama Conference Center, Yokohama,
Japan. 相似文献
998.
介绍了测量不确定度的评定方法及其在基准试剂纯度、干涉滤光片波长标准物质、锌合金成分标准物质中的应用实例。 相似文献
999.
H. El-Ghandoor Ibraheem Nasser M. A. Abd-El Rahman R. Hassan 《Optics & Laser Technology》2000,32(4):281
A new technique (El-Ghandoor et al., Opt. Laser Technol. 31(7) (1999) 481–488) has been applied to study the shape of transverse interference fringes, instead of multiple beam Fizeau fringes (Marhic, Stein, Appl. Phys. Lett. 35 (1975) 1678–1682), from a GRIN optical fiber. In this technique, a laser light sheet is used to illuminate and pass directly through the optical fiber. Theoretical expressions are derived for the optical path differences of three groups of interference beams. The first one passes through the cladding, the core, and then the cladding once again; the second passes through the cladding only, and the third passes through the surrounding air. Theoretical expressions for the shape of transverse interference fringes formed across isotropic non-absorbing optical fibers are also calculated. 相似文献
1000.
The wave equation of light beam propagation was written in the form of an axial-coordinate-dependent Schrdinger equation, and the expectation value of a dynamical variable, the trial function of variational approach and the ABCD law were discussed by use of quantum mechanics approach. In view of the evolution equations of expectation values of dynamical variables in the framework of quantum mechanics, the definition of a potential function representing the beam propagation stability and its universal formula with the quality factor, the universal formula of beam width and curvature radius for a paraxial beam and cylindrically symmetric non-paraxial beam, the general formula of second derivative of beam width with respect to the axial coordinate of beam for a paraxial beam, and the general criteria of the conservation of beam quality factor and the existence of a potential well of a potential function for a paraxial beam, were given or derived, respectively. Starting with the same trial function, the comparative research of our formulation with variational approach was done, which gave some further insight into the physical nature of a beam propagation parameters. The ABCD law of non-paraxial beam was discussed in terms of the definition of the non-paraxial expectation value of a dynamical variable for the first time. The applications to the media of constant second derivative of beam width with respect to the axial coordinate of a beam, square law media and the media of constant refractive index in the momentum representation were discussed, respectively. 相似文献