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排序方式: 共有476条查询结果,搜索用时 15 毫秒
41.
Yusuke Iwasaki Masato Goto Keisuke Mochizuki Emi Terayama Rie Ito Koichi Saito Norihiro Sugino Tsunehisa Makino Hiroyuki Nakazawa 《Biomedical chromatography : BMC》2011,25(4):503-510
A selective and sensitive HILIC‐MS/MS method for the simultaneous quantification of nicotine and its metabolites in human maternal and cord sera was developed and validated. After solid‐phase extraction, LC separation was achieved on a hydrophilic interaction chromatography. The validated method is capable of selective identification as well as accurate and sensitive quantification. Analyte recovery ranged from 86.2 to 107.7% and intra‐ and inter‐day assay precision were less than 15% relative standard deviation. This sensitive HILIC‐MS/MS method can be used to determine nicotine and its metabolic profile in smokers. This validated method is useful for the determination of nicotine and its metabolites in human serum in future studies of the effects of nicotine exposure on neonatal outcome. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
42.
T. Makino 《Optical and Quantum Electronics》1993,25(7):473-481
The spectral linewidth of a partly gain-coupled MQW DFB laser with a quantum-well grating is analysed using the transfer-matrix method. The effective linewidth enhancement factor and the longitudinal spontaneous emission enhancement factor are calculated by newly derived analytical expressions in terms of the transfer matrix. 相似文献
43.
T. Idehara Y. Shimizu S. Makino K. Ichikawa T. Tatsukawa I. Ogawa G. F. Brand 《International Journal of Infrared and Millimeter Waves》1997,18(2):391-403
Amplitude modulation of gyrotron by a small modulation of the anode voltage is calculated using an energy transfer formula.
Experimental measurements using a submillimeter wave gyrotron are in good agreement. One hundred percent modulation of the
output at frequencies up to several hundred kilohertz has been achieved with anode modulation levels of only a few percent.
Numerical calculations lend further support to the experimental results. 相似文献
44.
T. Makino M. Inada K. Yoshida I. Umezu A. Sugimura 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1391-1393
We studied the structural and optical properties of silicon (Si) nanoparticles (np-Si) prepared by pulsed laser ablation (PLA) in hydrogen (H2) background gas. The mean diameter of the np-Si was estimated to be approximately 5 nm. The infrared absorption corresponding to Si-Hn (n=1,2,3) bonds was observed at around 2100 cm-1, and a Raman scattering peak corresponding to crystalline Si was observed at around 520 cm-1. These results indicate that nanoparticles are not an alloy of Si and hydrogen but Si nanocrystal covered by hydrogen or hydrogenated silicon. This means that surface passivated Si nanoparticles can be prepared by PLA in H2 gas. The band-gap energy of np-Si prepared in H2 gas (1.9 eV) was larger than that of np-Si prepared in He gas (1.6 eV) even though they are almost the same diameter. After decreasing the hydrogen content in np-Si by thermal annealing, the band-gap energy decreased, and reached the same energy level as np-Si prepared in He gas. Thus, the optical properties of np-Si were affected by the hydrogenation of the surface of np-Si. PACS 81.15.Fg; 61.46.+W; 78.67.Bf 相似文献
45.
Tatsuo Narikiyo Junichiro Sahashi Kazutomo Misao 《Nonlinear Analysis: Hybrid Systems》2008,2(2):231-241
In this paper a new control methodology for underactuated mechanical systems is proposed. The basic idea of this method is to combine passive velocity field control with decoupling vector field. In order that the underactuated mechanical systems can be stabilized at the desired position after settling on the desired velocity vector field, novel control strategies are proposed. Proposed control strategies are applied to the underactuated planar three-link manipulator and underactuated planar body. Simulations demonstrate the usefulness and effectiveness of the proposed control methodology. 相似文献
46.
Optical Review - Dynamics of water content in a biological tissue is an important information of a biological activity. However, although the conventional measurement method measures the total... 相似文献
47.
In recent years, the hole drilling method for determining residual stresses has been implemented with optical methods such
as holographic interferometry and ESPI to overcome certain limitations of the strain rosette version of hole drilling. Although
offering advantages, the interferometric methods require vibration isolation, a significant drawback to their use outside
of the laboratory. In this study, a 3D image correlation approach was used to measure micron-sized surface displacements caused
by the localized stress relief associated with hole drilling. Residual stresses were then found from the displacements using
non-dimensional relations previously derived by finite element analysis. A major advantage of image correlation is that it
does not require interferometric vibration isolation. Experiments were performed to check the ability of this new approach
for uniaxial and equi-biaxial states of stress. Stresses determined by the approach were in good agreement with computed values
and those determined by hole drilling using holographic interferometry. 相似文献
48.
Back Cover: CH Activation Generates Period‐Shortening Molecules That Target Cryptochrome in the Mammalian Circadian Clock (Angew. Chem. Int. Ed. 24/2015) 下载免费PDF全文
Tsuyoshi Oshima Dr. Iori Yamanaka Dr. Anupriya Kumar Dr. Junichiro Yamaguchi Dr. Taeko Nishiwaki‐Ohkawa Kei Muto Rika Kawamura Dr. Tsuyoshi Hirota Prof. Dr. Kazuhiro Yagita Prof. Dr. Stephan Irle Prof. Dr. Steve A. Kay Prof. Dr. Takashi Yoshimura Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2015,54(24):7200-7200
49.
50.
Melting characteristics of phase change material by natural convection heat transfer inside horizontal rectangular capsules are examined experimentally. The capsules are heated isothermally and three kinds of aspect ratios (qH/W=3, 1 and 1/3) are provided. Octadecane and ice are used, respectively, as the phase change material. A method of analysis applying the empirical correlations for natural convection heat transfer in a vertical or horizontal enclosure to the melting in the rectangular capsules is presented. The predicted results show good agreement with the experimental data. For the melting of octadecane and ice, it is found that the effect of aspect ratio on the melting process is not significant for the range ofB=1/3 to 3. 相似文献