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991.
双波长敏感的光致聚合物全息存储材料 总被引:9,自引:4,他引:9
介绍了一种以聚乙烯醇为粘结剂,丙烯酰胺和亚甲基双丙烯酰胺作为单体,赤藓红和亚甲基蓝作为光引发剂,三乙醇胺作为共引发剂的光致聚合物材料。材料能同时对红光和绿光敏感,用红光和绿光分别对材料曝光,测得的两种衍射效率分别不低于30%,灵敏度不低于25cm^2/J。该材料对红光的最大响应空间频率为2274 lp/mm,相应的衍射效率为27.73%,响应范围为1600∽2800lp/mm;对绿光的最大响应空间频率为2350 lp/mm.相应的衍射效率为25、72%,响应范围为1700∽3000 lp/mm。在材料的同一点上进行红光和绿光的波长复用全息存储,当用红光或绿光再现时单幅图像清晰,信噪比高,两幅图像之间无任何干扰,该材料适合双波长全息存储。 相似文献
992.
Laboratory formation of four isomers of C5H2 molecule is reported and detection of the ring-chain isomer (isomer 1) of C5H2 in cosmic objects has been suggested. For identification of a molecule in cosmic objects, one of the required input data
is EinsteinA-coefficients (radiative transition probabilities) for the molecule. Here, we report EinsteinA-coefficients for electric dipole transitions in the ring-chain isomer of C5H2 among the rotational levels of the ground electronic and ground vibrational states up to 21 cm−1. 相似文献
993.
The influence of material and thickness on the subwavelength imaging performance of a negative dielectric constant slab is studied. Resonance in the plane-wave transfer function produces a high spatial frequency ripple that could be useful in fabricating periodic structures. A cost function based on the plane-wave transfer function provides a useful metric to evaluate the planar slab lens performance, and using this, the optimal slab dielectric constant can be determined. 相似文献
994.
This paper simulated the advection and diffusion behaviors of the moving magnetic fluid in the vessel in the high-gradient magnetic field using Navier–Stokes equations. The particles accumulation behavior and the streamlines and the contour of concentration are all affected by the susceptibility, intensity of magnetic field and its gradient, and the flow velocity and also by the difference in size of vessels. The typical accumulation behaves as a solid obstacle in the flow as result of the competing between magnetic and fluid drag forces, and gives rise to a rigidly bound core region followed by a wash away region near the vessel boundary under the condition of 10 mm vessel in width. While the vessel is near 1 mm in width, the magnetic force is exerted almost on the whole vessel area, the vortex is not seen, the wash away area disappears and the concentration changes in the whole vessel. The results of the analysis provide meaningful information on ferrofluid transport and stabilization for various magnetic drug targeting and the magnetic fluid sealing, and other use in industrial and medical fields. 相似文献
995.
996.
997.
Yuanyuan Li Jie Sun Li Wang Peng Zhan Zhishen Cao Zhenlin Wang 《Applied Physics A: Materials Science & Processing》2008,92(2):291-294
A sensor based on surface plasmon resonance (SPR) of plasmonic crystals fabricated via a colloidal-crystal-assisted templating
method is studied. Plasmonic crystals are prepared by depositing a thin gold (Au) layer onto a two-dimensional array of polystyrene
spheres self-assembled on a quartz substrate. The enhanced transmission as a result of the SPR of Au plasmonic crystals, which
are immersed in different ambient liquids, are measured and compared with that of polystyrene (PS) microsphere templates of
different sizes, both before and after removal of Au nanoprisms formed on the quartz substrate through pores among the spheres.
It is found that the measured sensitivities exhibit a linear dependence on the refractive index of the surrounding medium
and are linked to coupling effects between SPRs on the corrugated Au film and nanoislands. The feasibility of the SPR system
in molecular monolayer detection is further demonstrated through a formation of alkanethiolate self-assembled monolayers on
the Au film surface, which causes a 4 nm red-shift of the main SPR.
PACS 07.07.Df; 73.20.Mf; 78.66.-w; 81.16.Dn 相似文献
998.
An improved transmission line model to study the thermal effects in semiconductor laser diodes is reported in this paper.
The temperature effects in the laser characteristics are obtained by incorporating temperature dependent gain and carrier
density equations for the laser cavity. These primary factors are introduced in the regular transmission line laser model
to estimate the static and dynamic characteristics of an 1.3μm InGaAsP double heterostructure laser diode. The results show
good agreement with the experimental observation and solution of rate equations referred in the literature. The key feature
of this model is that it provides the laser spectra at various temperatures. Based on the model, time dependent evolution
of optical spectrum, temperature dependent optical output and frequency chirp are evaluated. Further the distribution of photon
and electron density within the cavity is also determined. 相似文献
999.
1000.
Jongho Shin Kyungsik Jang Ki-Soo Lim Ik-Bu Sohn Young-Chul Noh Jongmin Lee 《Applied Physics A: Materials Science & Processing》2008,93(4):1015-927
We report the spectroscopic properties of femtosecond laser-irradiated sodium-alumino-borate glass doped with silver and gold
ions. We precipitated gold and silver nanoparticles by laser irradiation and annealing at 400°C for 30 min. The irradiation
and annealing treatment produced different absorption and emission characteristics in Au3+ doped and Au3+, Ag+ codoped glasses, and the possible mechanisms of the observed results are discussed. The size of the nanoparticles was estimated
by TEM and absorption band analysis. 相似文献