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991.
光学系统时间畸变和色时间滞后的研究 总被引:1,自引:1,他引:0
本文对皮秒和飞秒技术中瞬态现象测量系统所用的特殊光学系统校正时间畸变和压缩色时间滞后的问题进行了讨论。实验证明用该方法设计研制的光学系统校正效果显着。 相似文献
992.
IntroductionTheincreasingnecessity0fpharmacologicalresearchforchiraldrugshasrenderedchiralseparationanactiveareaincaPillaryelectroph0resis(CE)today.Variousmodes0fCE,includingcaPillaryzoneelectroph0resis(CZE),micellarelectrokineticchromatography(MEKC),caPillarygelelectrophoresis(CGE)andcapillaryisotachophoresis(CITP),havebeenappliedforthispurp0se',amongwhichCZEisthemostpopularoneforitshighefficiency,lowexpenseandeaseofoperation.Forsuccessfulchiralseparati0ninCZE,theselectortypeisofcr… 相似文献
993.
文中用R矩阵传播子方法计算了He-HCN超精细碰撞跃迁截面和速率常数,给出了新的理论计算结果,并讨论了势函数长程部分对结果的影响 相似文献
994.
995.
Raman and infrared spectra have been recorded for trimethylarsenic dichloride, dibromide and their deuterated analogs and vibrational assignments were made for the skeletal modes of these compounds. The spectra of the dichloride and its deuterated analog were interpreted in terms of a trigonal bipyramidal structure, D3h symmetry, whereas the spectra of the dibromides were interpreted using the ionic model, [(CH3)3AsBr]+Br−, having C3v symmetry. Using a generalized valence force potential field, normal coordinate analyses data were obtained for the dichloride and the dibromide. Included in this data are potential energy distributions for a set of symmetry coordinates. The force fields obtained for the dichloride and dibromide were used to calculate frequencies for the corresponding deuterated compounds. The discrepancies between the observed and calculated frequencies for the deuterated compounds are discussed in terms of the assumptions made. 相似文献
996.
Y.?Xue G.?Wang H.-F.?Zhang J.-Y.?GaoEmail author 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,33(1):123-127
We propose a novel scheme for light amplification and gain equalization by
quantum interference. We find that the laser amplification can be observed at
three specific probe frequencies in a four-level system. Furthermore, we
show that three gain peaks can be combined into one to obtain
gain equalization. 相似文献
997.
R.?Long T.?Rom W.?H?nsel T. W.?H?nsch J.?ReichelEmail author 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,35(1):125-133
We describe a chip-based magnetic conveyor that transports
ultracold atoms with high positioning accuracy over long distances,
into an interaction region which is well separated from the
magneto-optical trap and gives good optical access to the atoms. The
conveyor can work in two different modes, with or without external
bias field. The transport potential is generated by a two-layer
conductor pattern, enabling a significantly smoother transport than
our earlier single-layer conveyor. This is confirmed by numerical
field calculations, using an optimization procedure that minimizes
shape deformations as well as deviations from the linear transport
path. We experimentally demonstrate the use of this conveyor in the
mode with external bias field, transporting a cloud of cold atoms
over a linear distance of 6 cm and a total distance of 24 cm. We
also describe an on-chip quadrupole trap that can be rotated by
π/2. This trap is used to remove design constraints on the
orientation of the laser beams in the surface magneto-optical trap.
The long-distance conveyor is a versatile tool for experiments with
trapped cold atoms, and can achieve sub-micrometric positioning
precision. Possible applications of this tool are discussed. 相似文献
998.
Implementation of a multiple round quantum dense coding using nuclear magnetic resonance 总被引:1,自引:0,他引:1
Zhang?Jingfu?Email author Xie?Jingyi Wang?Chuan Deng?Zhiwei Lu?Zhiheng Long?Guilu 《中国科学G辑(英文版)》2005,48(6):706-715
~~Implementation of a multiple round quantum dense coding using nuclear magnetic resonance1. Bennett, C. H., Wiesner, S. J., Communication via one- and two-particle operators on Einstein-Podolsky-Rosen states, Phys. Rev. Lett., 1992, 69(20): 2881-2884.
2. Mattle, K., Weinfurter, H., Kwiat, P. G. et al., Dense coding in experimental quantum communication, Phys. Rev. Lett., 1996, 76(25): 4656-4659.
3. Fang, X. M., Zhu, X. W., Feng, M. et al., Experimental implementation of dens… 相似文献
999.
[structure: see text] The de novo synthesis of the C9 and C27 sugar subunits (2) and (3), respectively, of the potent antitumor agent, apoptolidin, has been accomplished. A titanium tetrachloride-mediated asymmetric anti glycolate aldol addition was utilized to establish the 4' and 5' stereogenic centers of each of the three monosaccharides. Elaboration of the aldol adducts efficiently provided the three sugar units. A beta-selective glycosidation completed the construction of the C27 disaccharide. 相似文献
1000.
Let n be a positive integer and P=diag(−In−κ,Iκ,−In−κ,Iκ) for some integer κ∈[0,n]. In this paper, we prove that for any convex compact smooth hypersurface Σ in R2n with n?2 there always exists at least one closed characteristic on Σ which possesses at least 2n−4κ Floquet multipliers on the unit circle of the complex plane, provided Σ is P-symmetric, i.e., x∈Σ implies Px∈Σ. 相似文献