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121.
Chih-Wei Chiang Subrata Kumar Das Huang-Shih Liao 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(2):197-203
We report the first inter-comparison of vertical profiles of aerosols and clouds derived from space (CALIPSO) and ground based lidar over Chung-Li, Taiwan. Results show that inter-comparison is closer in case of aerosols than clouds. The strength/shortcoming of the comparison has been also discussed. An iterative calculation to retrieve extinction-to-backscatter ratio (lidar ratio) by using sun-photometer and CALIPSO data is also documented. By using the mentioned method, a mean lidar ratio of 23.5±8.2 sr was found. The derived lidar ratios are lower than former studies. The possible reasons for the difference have been discussed in this paper. The discussed methodology will be helpful to reduce the uncertainty of optical parameters derived from lidar data especially near the surface where the atmosphere is inhomogeneous. 相似文献
122.
Electronic chirality near the Dirac point is a key property of graphene systems, which is revealed by the spectral intensity patterns as measured by angle-resolved photoemission spectroscopy under various polarization conditions. Specifically, the strongly modulated circular patterns for monolayer (bilayer) graphene rotate by ±90° (±45°) in changing from linearly to circularly polarized light; these angles are directly related to the phases of the wave functions and thus visually confirm the Berry's phase of π (2π) around the Dirac point. The details are verified by calculations. 相似文献
123.
Y. F. Chen Y. J. Huang P. Y. Chiang Y. C. Lin H. C. Liang 《Applied physics. B, Lasers and optics》2011,103(4):841-846
A short-cavity Nd:YVO4 laser is employed to confirm that a spontaneous mode locking (SML) typically occurs without employing an extra nonlinearity.
We further experimentally demonstrate that reducing the number of longitudinal lasing modes can diminish the phase fluctuation
and effectively improve the SML pulse stability. Considering the spatial hole-burning (SHB) effect, an analytical expression
is derived to accurately estimate the number of longitudinal lasing modes for a practical design guideline. 相似文献
124.
A method, novel to our knowledge, for effective mirror image suppression in Fourier-domain optical coherence tomography based on a phase shift between neighboring A-mode scans is demonstrated. By realizing that the phase shifts of the real and mirror images are mutually reversed and assuming that the real image intensities of the two successive A-mode scans are the same, we can solve a set of two coupled equations to obtain the real image signals. The images based on the scanning of a high-resolution spectral-domain optical coherence tomography system are processed to show effective mirror image suppression results. Compared with a similar method of broad application, our approach has the advantages of shorter process time and higher flexibility in selecting the concerned image portions for processing. 相似文献
125.
Let An be the group of n×n even permutation matrices, and let Vn be the real linear space spanned by An. The purpose of this note is to characterize those linear operators φ on Vn satisfying φ(An)=An. This answers a question raised by C.K. Li, B.S. Tam, N.K. Tsing [Linear Algebra Appl., to appear]. 相似文献
126.
Kuei-Ming Chen Yen-Hsien Yeh Yin-Hao Wu Chen-Hao Chiang Din-Ru Yang Chu-Li Chao Tung-Wei Chi Yen-Hsang Fang Jenq-Dar Tsay Wei-I Lee 《Journal of Crystal Growth》2010,312(24):3574-3578
The bowing curvature of the free-standing GaN substrate significantly decreased almost linearly from 0.67 to 0.056 m−1 (i.e. the bowing radius increased from 1.5 to 17.8 m) with increase in inductively coupled plasma (ICP) etching time at the N-polar face, and eventually changed the bowing direction from convex to concave. Furthermore, the influences of the bowing curvature on the measured full width at half maximum (FWHM) of high-resolution X-ray diffraction (HRXRD) in (0 0 2) reflection were also deduced, which reduced from 176.8 to 88.8 arcsec with increase in ICP etching time. Decrease in the nonhomogeneous distribution of threading dislocations and point defects as well as VGa–ON complex defects on removing the GaN layer from N-polar face, which removed large amount of defects, was one of the reasons that improved the bowing of the free-standing GaN substrate. Another reason was the high aspect ratio of needle-like GaN that appeared at the N-polar face after ICP etching, which released the compressive strain of the free-standing GaN substrate. By doing so, crack-free and extremely flat free-standing GaN substrates with a bowing radius of 17.8 m could be obtained. 相似文献
127.
128.
Cheng‐Hung Chang Kun‐Li Wang Jyh‐Chiang Jiang Der‐Jang Liaw Kueir‐Rarn Lee Juin‐Yih Lai Kuo Yuan Chiu Yuhlong Oliver Su 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5659-5669
A series of highly organosoluble polyamides with high modulus having propeller‐shaped triarylamine were synthesized using aromatic diacid chlorides by low‐temperature solution polycondensation. The polyamide films had strong, tough, flexible, and amorphous properties. These polymers revealed electrochromic characteristics both in the visible range and near‐infrared (NIR) region, with a color change from pale yellowish at its neutral state to green and blue at its oxidized state at applied potentials ranging from 0.00 to 1.35 V. Cyclic voltammetry (CV) of the polymer films cast onto an indium tin oxide (ITO)‐coated glass substrate exhibited two reversible redox couples at potentials of 0.80–0.87 V and 1.19–1.25 V, respectively, vs. Ag/Ag+ in acetonitrile solution. From the combination of the experimental and computational study, we proposed an oxidation mechanism based on molecular orbital (MO) theory, which well explains the CV experimental result. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
129.
Shiun-Sheng JanJung-Lung Chiang Ying-Chung Chen Jung-Chuan ChouChien-Chuan Cheng 《Analytica chimica acta》2002,469(2):205-216
The sol-gel-derived lead titanate (PbTiO3) membrane has been successfully applied as a pH sensitive layer to form the PbTiO3 gate ion-sensitive field-effect transistor (ISFET). There exhibit the excellent quasi-Nernstian response of 56-59 mV pH−1, good surface adsorption and anticorrosion characteristics via the C-V measurement of the EIS structure. At a specific pH concentration, the output and transfer characteristics are very similar to the behaviours of MOSFETs, and the ISFET model can be derived by the modified MOSFET model. As it operated in the nonsaturation region, there exhibits a linear pH response of about 56-59 mV pH−1. On the other hand, as it operated in the saturation region, the pH response and linearity can be controlled by adjusting the VGS values, e.g. the pH responses of −4.2, −24.8 and −31.3 μA pH−1 and the correlation coefficients of 0.9491, 0.9995 and 0.9996 at VGS=1, 3 and 5 V can be obtained, respectively. Besides, in order to get the best pH response and the minimized leakage current, the heat treatment temperature of the PbTiO3 membrane must be limited between 350 and 450 °C. 相似文献
130.