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91.
We present an all-fiber bidirectional passively mode-locked soliton laser with what we believe is a novel cavity configuration. Using a four-port circulator, we incorporate two different semiconductor saturable absorber mirrors (SESAMs) into the laser cavity, which enables bidirectional mode locking. The laser allows the generation of two independent countercirculating mode-locked pulse trains, each with an individual fundamental repetition rate that can be adjusted by varying the SESAM pigtail length. Two countercirculating pulse trains with repetition rates of 21.3 and 15.2 MHz are obtained simultaneously. By controlling the intracavity loss imposed on these two pulse trains, either one of the two pulse trains can be switched on or off. The bidirectional operation with other repetition rates is also demonstrated. 相似文献
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93.
A molecular dynamic method in conjunction with a statistic test has been utilized to model chiral recognition of a -phenylethylamine on heptakis (2,6-di-O-butyl-3-O-butyryl)-b -cyclodextrin in gas chromatography. The modelling data correlated with the chromatographic elution order, and indicated that the preferred site of a -phenylethylamine is the interior of cavity. 相似文献
94.
LI Ming LI Wei-Hua YANG Xing-Fan PAN Qing XIANG Dao HUANG Wen-Hui TANG Chuan-Xiang LIN Yu-Zheng 《中国物理C(英文版)》2010,34(2)
Magnetic bunch compressor is one of the key technologies on the path to next generation accelerator driven facilities. In this paper we report the design principles and the first experimental research of the bunch compressor developed at Chinese Academy of Engineering Physics (CAEP). The length of the bunch after compressor is found to be about 0.7 ps (rms) and the peak current exceeds 500 A when operated in the optimized condition. The sensitivity of the bunch length on the phase of the acceleration field and magnetic field of the bunch compressor was also measured and analyzed. 相似文献
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96.
De‐Qing Zhang Zhe‐Ming Wang Liang Ding Bin Zhang Wei Xu Dao‐Ben Zhu Chun‐Hua Yan 《中国化学》2001,19(10):966-975
New triphenylamine derivatives 1, 2, 3, and 4 were synthesized and characterized by IR, FAB‐MS, EPR and EA. All of them displayed similar absorption and fluorescence spectra except compound 1, for which a possible explanation was proposed. Quasi‐reversible oxidation waves at about 0.76 V (vs. SCE) and 1.1 V for nitronyl nitroxide and iminyl nitroxide respectively as well as irreversible one at about 1.5 V for triphenylamine group were detected with cyclic voltammetry for compounds 1, 2, 3 and 4. Crystal structures of 2 and 4 were determined by X‐ray diffraction analysis. Their crystal data are as follows: for 2: monoclinic, C2/c, a = 1.69914 (4), b = 1.37435(5), c = 1.24621(5) ran, β= 106.553(2)°, V = 2.7896(2) nm3 Z = 4; for 4: orthorhombic, Pbca, a = 1.95970(6), b = 1.33096(4), c = 4.84691(14) nm, V = 12.6421(7) nm3, Z = 8. Magnetic studies indicated that all of them showed antiferromagnetic properties in solid state, but with strong intermolecular spin‐spin coupling as indicated by the relatively large values of 6, in particular for 4 (θ = ?12 K). Possible spin‐spin interaction mechanism was suggested based on the crystal structures of 2 and 4. 相似文献
97.
用毛细管离子分析 (CIA)法 ,采用 10mmol·L- 1咪唑为背景电解质 ,4 0 %甲醇为选择性改性剂 ,在 pH 2 .5、分离电压为 2 5kV、柱温为 2 2℃的电泳条件下 ,采用间接紫外检测 (2 14nm ) ,在5min内测定了人发中铝 ,方法简便、快速、灵敏度高、重现性好、测定成本低 相似文献
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100.
Measuring the one-particle excitations of ultracold fermionic atoms by stimulated Raman spectroscopy
We propose a Raman spectroscopy technique which is able to probe the one-particle Green function, the Fermi surface, and the quasiparticles of a gas of strongly interacting ultracold atoms. We give quantitative examples of experimentally accessible spectra. The efficiency of the method is validated by means of simulated images for the case of a usual Fermi liquid as well as for more exotic states: specific signatures of, e.g., a d-wave pseudogap are clearly visible. 相似文献