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991.
Let s : S2 → G(2, 5) be a linearly full totally unramified pseudo-holomorphic curve with constant Gaussian curvature K in a complex Grassmann manifold G(2, 5). It is prove that K is either 1 4 1 or 4/5 if s is non-±holomorphic. Furthermore, K = 1/3 if and only if s is totally real. We also prove that the Gaussian curvature K is either 1 or -4/3 if s is a non-degenerate holomorphic curve under some conditions. 相似文献
992.
Giovanni Gilardi Sanshui Xiao Romeo Beccherelli Antonio d’Alessandro N. Asger Mortensen 《Photonics and Nanostructures》2012,10(1):177-182
We numerically demonstrate near-zero transmission of light through two-dimensional arrays of isolated gold rings. The analysis of the device as an optofluidic sensor is presented to demonstrate the tuning of the device in relation to variations of volume and refractive index of an isotropic fluid positioned over the structure. We also evaluate the performance of the device with respect to geometrical parameters of the rings. 相似文献
993.
994.
Ocean internal waves interpreted as oscillation travelling waves in consideration of ocean dissipation 下载免费PDF全文
Most studies of the synthetic aperture radar remote sensing of ocean internal waves are based on the solitary wave solutions of the Korteweg-de Vries (KdV) equation, and the dissipative term in the KdV equation is not taken into account. However, the dissipative term is very important, both in the synthetic aperture radar images and in ocean models. In this paper, the traveling-wave structure to characterize the ocean internal wave phenomenon is modeled, the results of numerical experiments are advanced, and a theoretical hypothesis of the traveling wave to retrieve the ocean internal wave parameters in the synthetic aperture radar images is introduced. 相似文献
995.
Polarization-dependent linear absorption, second-harmonic generation (SHG) and 3rd-order nonlinearities of wellaligned ZnO nanorod arrays have been investigated with ps pulses. The depressed spectral width and the enhanced intensity of reflective SHG along the long axis of ZnO nanorods were observed by using p-polarized pulses, which is explained by the optical confinements. The nonlinear absorption coefficient measured with s-polarization reached the maximum 4.0×10^4cm/GW at the wavelength -750nm, which revealed a large two-photon resonance absorption attributed to the quantum confined exciton when the polarization is vertical to the long axis of ZnO nanorod. 相似文献
996.
997.
Pu Zhou Zilun Chen Xiaolin Wang Xiao Li Zejin Liu Xiaojun Xu Jing Hou Zongfu Jiang 《中国光学快报(英文版)》2008,6(7)
We demonstrate a scalable architecture for coherent combining of pulsed fiber lasers.A new method for generating synchronous pulsed fiber lasers by direct phase modulation is proposed and investigated.It is shown that phase modulated mutually coupled laser array can be a steady synchronous pulsed fiber laser source.The synchronous pulsed fiber lasers are coherently combined with an invariable phase difference of π in adjacent lasers.Neither active phase control nor polarization control is taken in our experiment. 相似文献
998.
372-mJ long pulse pyrotechnically pumped laser 总被引:2,自引:0,他引:2
A pyrotechnically pumped Nd glass laser is demonstrated by the use of pyrotechnic flashlamps composed of several chemical materials arranged in a stable plane concave resonator cavity. The flashlamp was made of chemical mixture with oxidant, fuel, and binder. The emission spectrum of pyrotechnic flame covered most of the absorption bands of Nda+ in phosphate glass. Under 4.56-g chemical mixture pumping, long pulse output power of about 5.5 W was achieved. 相似文献
999.
ZhiHu Yang Ying Cui XiMeng Chen ZhangYong Song JianXiong Shao FangFang Ruan HongQiang Zhang Juan Du YuWen Liu ZhiMing Gao XiaoAn Zhang KeXin Zhu DeYang Yu XiaoHong Cai 《中国科学G辑(英文版)》2008,51(10):1463-1469
The X-ray spectra of Nb surface induced by Ar
q+ (q = 16,17) ions with the energy range from 10 to 20 keV/q were studied by the optical spectrum technology. The experimental
results indicate that the multi-electron excitation occurred as a highly charged Ar16+ ion was neutralized below the metal surface. The K shell electron of Ar16+ was excited and then de-excited cascadly to emit K X-ray. The intensity of the X-ray emitted from K shell of the hollow Ar
atom decreased with the increase of projectile kinetic energy. The intensity of the X-ray emitted from L shell of the target
atom Nb increased with the increase of projectile kinetic energy. The X-ray yield of Ar17+ is three magnitude orders larger than that of Ar16+.
Supported by the National Natural Science Foundation of China (Grant Nos.10774149 and 10405025) 相似文献
1000.
论中国海洋砂矿床类型 总被引:1,自引:0,他引:1
阮汀 《宁波大学学报(理工版)》1988,(2)
本文总结了作者二十多年砂矿工作的经验,搜集了国内近三百处海洋砂矿床(点)五十余种矿床类型划分的资料,比照国外同类型矿床,结合我国矿床特征,提出了新的海洋砂矿分类原则,矿床工业类型、成因-形态类型、成矿时代类型和保存类型等的划分系统,以及今后的找矿方向。 相似文献