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SPME/GC-MS分析冷水花的挥发性成分 总被引:2,自引:0,他引:2
利用固相微萃取/气相色谱-质谱(SPME/GC-MS)联用技术分析冷水花挥发性化学成分。共鉴定出61个化学成分,占总挥发性成分的98.42%。冷水花挥发性化学成分主要是1-甲基-5-甲烯基-8-(1-异丙基)-[s-(E,E)]-1,6-环癸二烯(20.03%),石竹烯(13.38%),1-萘胺(5.27%),愈创兰油烃(5.20%),N-(4-羟苯基)-丁酰胺(5.12%),α-法呢烯(4.73%),1-甲基-1-乙烯基-2,4-二丙烯基-环己烷(4.59%)等。 相似文献
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Using the vertical evaporation technique we fabricated saturable absorbers by transferring the double-wall carbon nanotubes
(DWCNT) onto a hydrophilic quartz substrate. The fast recovery time and the saturation intensity of the absorber were measured
to be 228 fs and 130 μJ/cm2, respectively, at 1060 nm. The modulation depth of the absorber was about 3.7%. Passive mode-locked Nd:GdVO4 laser was demonstrated. The continuous wave mode-locked pulses pulse duration is 5.6 ps and the largest average output power
is 1.2 W at the pump power of 9.5 W. To the best of our knowledge, this is the first demonstration of high power continuous
wave mode locking laser with DWCNT absorber. 相似文献
958.
Rui Zheng 《Journal of Molecular Spectroscopy》2011,265(2):102-105
The rovibrational spectrum of the N2-N2O van der Waals complex has been recorded in the N2O ν1 region (∼1285 cm−1) using a tunable diode laser spectrometer to probe a pulsed supersonic slit jet. The observed transitions together with the data observed previously in the N2O ν3 region are analyzed using a Watson S-reduced asymmetric rotor Hamiltonian. The rotational and centrifugal distortion constants for the ground and excited vibrational states are accurately determined. The band-origin of the spectrum is determined to be 1285.73964(14) cm−1. A restricted two-dimensional intermolecular potential energy surface for a planar structure of N2-N2O has been calculated at the CCSD(T) level of theory with the aug-cc-pVDZ basis sets and a set of mid-bond functions. With the intermolecular distance fixed at the ground state value R = 3.6926 Å, the potential has a global minimum with a well depth of 326.64 cm−1 at θN2 = 11.0° and θN2O = 84.3° and has a saddle point with a barrier height of 204.61 cm−1 at θN2 = 97.4° and θN2O = 92.2°, where θN2(θN2O) is the enclosed angle between the N-N axis (N-N-O axis) and the intermolecular axis. 相似文献
959.
Rui Zhang Mingzhong Li Jianjun Wang Wentao Duan Feng Wang Xiaoshi Peng Xiaolin Tian 《Optics & Laser Technology》2011,43(1):179-182
Imaging VISAR is an important diagnostic tool for a variety of shock-related phenomena in laser-driven experiments. To adapt to various types of shaped driven pulse, the imaging VISAR needs an illuminating light with good shaping capability. Here, a flexible laser probe system was experimentally studied. Being generated from a 1064-nm DFB laser, the continuous wave was modulated by a waveguide amplitude modulator driven by 10 GS/s arbitrary waveform generator. After being amplified by fiber amplifiers and Nd:YAG rod amplifiers, the signal pulse was frequency-converted to 532-nm green light by a thermally controlled LBO crystal with a final output energy larger than 10 mJ. Finally, the green light was coupled into a 1-mm core diameter, multimode fused silica optical fiber and propagated to the imaging VISAR. The probe laser could realize accurate pulse shaping with time resolution below 100 ps. Uniformity in intensity and capability of arbitrary pulse shaping provides great convenience for the analysis of experimental data. 相似文献
960.
In this paper, we firstly propose a new simple method to calculate entanglement swapping of χ-type entangled states, and then present a novel quantum steganography protocol with large payload. The new protocol adopts entanglement swapping to build up the hidden channel within quantum secure direct communication with χ-type entangled states for securely transmitting secret messages. Comparing with the previous quantum steganographies, the capacity of the hidden channel is much higher, which is increased to eight bits. Meanwhile, due to the quantum uncertainty theorem and the no-cloning theorem its imperceptibility is proved to be great in the analysis, and its security is also analyzed in detail, which is proved that intercept-resend attack, measurement-resend attack, ancilla attack, man-in-the-middle attack or even Dos(Denial of Service) attack couldn't threaten it. As a result, the protocol can be applied in various fields of quantum communication. 相似文献