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951.
952.
A.?A.?MakovetskiiEmail author Yu.?S.?Milyavskii L.?M.?Averina A.?A.?Zamyatin 《Journal of Applied Spectroscopy》2004,71(6):916-921
The curing kinetics of films produced from compositions based on UV-curable oligourethaneacrylates is investigated using, as a source of radiation, an individual spectral line separated by a monochromator from the radiation of a DRT-400 mercury tubular lamp. It has been established that in the region of spectral sensitivity of the composition, the curing time of the film is inversely proportional to the intensity of volumetric absorption of the radiation-source photons by the initiator at the lower surface of the film under study. Individual contributions of some of the lines to the process of composition curing by using the integral spectrum of the radiation source have been evaluated. The spectral-kinetic results obtained were confirmed when using the compositions under study as protective coatings of optical quartz fibers.Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 71, No. 6, pp. 836–840, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
953.
In this paper two new architectures for optical image verification are proposed. Both architectures are based on conventional joint transform correlators (JTCs) adopting a Fourier hologram and can significantly improve the recovered image quality. First, an input phase-only function is Fourier transformed and then interferes with a reference wave that is diffracted from a plane wave incident on another random phase mask. Second, two phase-only functions are placed at the two input sides of a beamsplitter such that the interference pattern of their Fourier transforms can be detected. To obtain a predefined target image in the output plane, one of the input phase functions is iteratively retrieved by the use of the projection onto constraint sets algorithm. Simulation results show that the less mean squared error and better image quality are obtained for both the binary and grayscale images. 相似文献
954.
RONG Jian & MA Zhongyu . China Institute of Atomic Energy Beijing China . Center of Nuclear Theoretical Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lan-zhou China . Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Correspondence should be addressed to Rong Jian 《中国科学G辑(英文版)》2004,47(2):189-198
There is growing evidence to suggest that the binding energy of nucleon in nuclear matter comes from a cancellation between large Lorentz scalar and vector potentials[1,2]. The relativistic approach has been of a great success in describing not only the ground state properties of stable nuclei, but also those of exotic nuclei. In the relativistic frame, the spin-orbit coupling can be deduced automatically, which is usually given by hand in the non-relativistic approach. The relativistic method… 相似文献
955.
Yusuke Arai Tetsuji Yano Shuichi Shibata 《Journal of Sol-Gel Science and Technology》2004,32(1-3):189-194
Microspheres of refractive index of nD > 2.0 have been investigated. The organic-inorganic hybrid microspheres of nD = 1.72 were prepared by the vibrating orifice technique using titanium-tetra-n-butoxide (TTBu) and diphenyldimethoxysilane (DPhDMS). For lasing demonstration, Eu3+-doped microspheres were prepared using europium (III) thenoyltrifluoroacetonate [Eu(TTFA)3] as the dopant. The particles have good spherical shape, smooth surface and high optical transparency. The diameters of the particles could be controlled to within 0.1 m. Subsequent heating of the microspheres at 550°C under oxygen atmosphere resulted in an increase in the refractive index up to nD = 2.6 with retention of the spherical shape. Resonant emission was confirmed from Eu3 +-doped microspheres after heating at 400–550°C, by pumping with the 514.5 nm line of a CW- Ar+laser. 相似文献
956.
Jong Kyu Kim 《Journal of fluorine chemistry》2004,125(3):369-375
Various fluorinated/chlorinated polymers were synthesized and characterized by FT-IR and NMR. Also, theoretical optic loss of the POF were investigated and proposed for the purpose of finding a definite rule of the optic loss.From the computation of the results, the modified equation was theoretically deduced, and the optic loss of each prepared polymer was measured and compared with the calculated optical loss of polymers. Also, it was found that the optic loss from the modified equation fitted well with the experimental data. 相似文献
957.
In the geometric optics approximation, we predict the effect of additional twisting of spinning particle trajectories in an absorbing medium. The effect is determined by the particle polarization (chirality) and the curvature of the particle trajectory. Using our results, we quantitatively estimate the deviation from the mirror reflection law for ultracold neutrons. 相似文献
958.
Haiyan Chen Jizhi Dai Yongzhi Liu 《International Journal of Infrared and Millimeter Waves》2004,25(12):1791-1798
IR integrated photonic amplifiers at 1.55m operation will have good foreground in optical phasedarray radars for splitters and signal processing. The saturation gain characteristics of IR integrated photonic waveguide amplifiers (taken Er3+Yb3+ co-doped phosphate glass waveguide amplifiers as an example) are studied theoretically. For the homemade laser glass materials the calculated saturation intensities are 2.22kw /cm2 for signal and 10.15kw/cm2 for pump. The effects of absorption saturation of signal and pump lights on the gain of amplifiers are discussed. 相似文献
959.
Xin?YangEmail author Mali?Gong Lei?Huang Ping?Yan Haitao?Zhang 《Optical and Quantum Electronics》2004,36(12):1079-1088
In this paper, the authors investigate the performance of recently presented run-length limited (4, 18) code for high density optical storage systems. The construction of the code is described simply. The code has code rate R = 1/3 and density ratio (DR) = 1.67. The bit error rate (BER) performance for decision feedback equalizer (DFE) and partial response maximum likelihood (PRML) detector are simulated, considering signal-to-noise ratio (SNR) and optical channel jitter. The result shows that the performance of the code is acceptable. The encoder and decoder of the code are implemented by complex programmable logic device (CPLD) chip and the hardware resources required for encoder and decoder arelow. 相似文献
960.
The electro-optic (E-O) properties of the slab polymer waveguide induced by electric poling have been studied experimentally. The thin film waveguide was prepared by a synthesized polymer polypelargonamide and poled by applying voltage between the electrodes. I–V curves and E-O characteristics of the polymer films were in-situ measured during poling. In order to evaluate the molecular dipole orientation under the poling field, the absorption spectra of this film was observed by FTIR. The E-O performance of the polymer slab film was also estimated by the Mach–Zehnder interferometer. 相似文献