Browsing by Issue Date, starting with "2009-05-04"

Now showing 1 - 20 of 50759

Terahertz spectroscopic study of vertically-aligned InN nanorods (vol 91, 163105, 2007)
(2009-05-04)
Ahn, H.
;
Ku, Y. -P.
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Wang, Y. -C.
;
Chuang, C. -H.
;
Gwo, S.
Temperature dependence of time-resolved photoluminescence spectroscopy in InAs/GaAs quantum ring
(2009-05-04)
Lin, C. H.
;
Lin, H. S.
;
Huang, C. C.
;
Su, S. K.
;
Lin, S. D.
We present detailed experimental results of the temperature dependence of continuous wave and time-resolved photoluminescence (PL) spectroscopy in self-assembled InAs/GaAs quantum dot and quantum ring nanostructures. A dramatic increase in PL decay time of the excited and ground states is observed in InAs quantum rings at high temperature. We speculate that the longer PL lifetime in quantum rings is due to the interplay among the dark states, ground states, and the reduced wave function overlapping between electrons and holes. A rate equation model is proposed to interpret the observed temperature dependence of the ground state exciton lifetime.
DEPRESSION- AND ANXIETY-LIKE BEHAVIORS OF A RAT MODEL WITH ABSENCE EPILEPTIC DISCHARGES
(2009-05-05)
Shaw, F. -Z.
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Chuang, S. -H.
;
Shieh, K. -R.
;
Wang, Y. -J.
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智慧型仿生系統研究中心
Depression and/or anxiety are major comorbidities of epilepsy. However, the contribution of absence epileptic discharges in psychiatric syndromes is inconclusive. This study aimed to clarify the influence of absence seizure in anxiety- and depression-like behaviors using normal Wistar rats and Long-Evans rats with spontaneous spike-wave discharges (SWDs). Anxiety-like behaviors were evaluated by the open field (OF) and elevated plus maze (EPM) tests, and depression-like behaviors by the forced swimming (FS) and sucrose consumption (SC) tests. Long-Evans rats displayed significantly higher frequency and longer duration in the open arms of the EPM and in the center zone of the OF than did Wistar rats. Normalized behavioral indexes by movement also were significantly higher in Long-Evans rats. An excess of SWD numbers was associated with lower indexes and worse movement in the two behavioral tests. Ethosuximide eliminated the seizure frequency-dependent relationship and also significantly increased all indexes of the EPM test. Additionally, Long-Evans rats revealed significantly longer immobility in the FS test and lower consumption of sucrose solution in the SC test than did Wistar rats. Meanwhile, no relationship was found between immobility of the FS test and SWD number. Ethosuximide ameliorated depression-like behavior of Long-Evans rats that was equal to that of Wistar rats. Thus, Long-Evans rats showed seizure frequency-related exacerbation in anxiety-like behavior; and they displayed a depressive propensity. Our data suggest that generalized SWDs may have distinct influences in anxious and depressive behaviors. (C) 2009 IBRO. Published by Elsevier Ltd. All rights reserved.
Crystal Growth of Glycine Controlled by a Focused CW Near-infrared Laser Beam
(2009-05-05)
Sugiyama, Teruki
;
Adachi, Takuji
;
Masuhara, Hiroshi
;
應用化學系
;
應用化學系分子科學碩博班
Crystal growth of glycine was accelerated just by focusing a CW 1064-nm laser beam at a position adjacent to a spontaneously generated glycine crystal in D(2)O. Its rate depended on the distance between the crystal and the focal spot. Interesting crystal growth and dissolution were found, which is considered to be due to Ostwald ripening,
交大e-News第047期
(2009-05-05)
Secretariat
;
國立交通大學秘書室
High oriented ZnO films by sol-gel and chemical bath deposition combination method
(2009-05-05)
Cheng, Hua-Chi
;
Chen, Chia-Fu
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Tsay, Chien-Yie
;
Leu, Jih-Perng
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材料科學與工程學系
Poly-crystalline ZnO films with high oriented columnar grains were deposited on ZnO-coated seed layers by chemical bath deposition (CBD) in an aqueous-solution bath containing zinc nitrate [Zn(NO(3))(2)center dot 6H(2)O], and dimethylamineborane (DMAB) at 60 degrees C without pre-activation especially. Sol-gel ZnO films on glass substrates were used as the seed layers which the mean size of the crystals in seed layer increased from several to approximately 80nm at temperature from 150 degrees C to 550 degrees C. The deposited ZnO films on the ZnO-coated seed surfaces are preferentially on the (0 0 2) plane and exhibit increased from several 10 nm to 150 nm with increasing seed layer grain size. (C) 2008 Elsevier B.V. All rights reserved.
New solutions to the constant-head test performed at a partially penetrating well
(2009-05-05)
Chang, Y. C.
;
Yeh, H. D.
;
環境工程研究所
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Institute of Environmental Engineering
The mathematical model describing the aquifer response to a constant-head test performed at a fully penetrating well can be easily solved by the conventional integral transform technique. In addition, the Dirichlet-type condition should be chosen as the boundary condition along the rim of wellbore for such a test well. However, the boundary condition for a test well with partial penetration must be considered as a mixed-type condition. Generally, the Dirichlet condition is prescribed along the well screen and the Neumann type no-flow condition is specified over the unscreened part of the test well. The model for such a mixed boundary problem in a confined aquifer system of infinite radial extent and finite vertical extent is solved by the dual series equations and perturbation method. This approach provides analytical results for the drawdown in the partially penetrating well and the well discharge along the screen. The semi-analytical solutions are particularly useful for the practical applications from the computational point of view. (C) 2009 Elsevier B.V. All rights reserved.
Probing Capacitive Coupling and Collective Transport in PbSe Quantum-Dot Arrays Using Scanning Tunneling Spectroscopy
(2009-05-07)
Ou, Yi-Ching
;
Wu, Jiun-Ji
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Fang, Jiye
;
Jian, Wen-Bin
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電子物理學系
Semiconductor quantum dots with diameters of several to tens of nanometers have been largely synthesized through colloidal techniques for nanoscience exploration of quantum confinement, Coulomb staircase, and artificial-atom states in individual quantum dots and self-assembling growth behavior. Although charge transport of three-dimensional quantum dot arrays has been attempted for study on the micron scale, the electrical properties of a nanoscale array, self-assembled from a single quantum dot through a bottom-up procedure, have not been explored yet. We control growth parameters to self-assemble different sizes of PbSe quantum-dot arrays on flat gold surface for scanning tunneling spectroscopy measurements. The current-voltage curves of the arrays are analyzed using a double-barrier tunnel junction model to acquire the shunt capacitance between the array and the gold substrate. The increment of this capacitance is small as the particle number increases extremely from 1 to 40. Thus the array cannot be taken as a simple semiconductor island. We apply collective transport theory to exploration of electron tunneling and capacitive coupling between PbSe quantum dots in the array.
半導体基板上において３族窒化物半導体層を形成する方法
(2009-05-07)
張俊彦
;
楊宗▲き▼
;
沈詩國
【課題】シリコン半導体基板を含む半導体基板上において３族窒化物半導体層を大面積でエピタキシャル成長を行う技術を提供する。【解決手段】半導体基板の表面をフッ酸（ＨＦ）洗浄及び高温における酸化物の除去後、さらに３族窒化物ナノロッドバッファ層（ＧａＮナノロッドバッファ層）を形成し、３族窒化物半導体層（ＧａＮエピ層）を３族窒化物ナノロッドバッファ層において被覆成長させることで、半導体基板上に３族窒化物半導体層を形成する。【選択図】図２
UWB Gilbert downconverter utilising a wideband LR-CR quadrature generator
(2009-05-07)
Syu, J. -S.
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Meng, C.
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Teng, Y. -H.
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電信工程研究所
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Institute of Communications Engineering
An ultra-wideband (UWB) I/Q downconverter with an LR-CR quadrature generator is demonstrated using 0.35 mu m SiGe HBT technology. The I/Q outputs of this generator are always in quadrature phase at any frequency while the BJT-type active mixer inherently tolerates much LO power difference for a. at gain response. Consequently, the amplitude imbalance and phase error of the I/Q outputs are less than 1 dB and 2 degrees in the RF frequency range 3-11 GHz.
Infrared absorption of gaseous c-ClCOOH and t-ClCOOH recorded with a step-scan Fourier-transform spectrometer
(2009-05-07)
Chu, Li-Kang
;
Lee, Yuan-Pern
;
應用化學系
;
應用化學系分子科學碩博班
;
Department of Applied Chemistry
Two conformers of ClCOOH were produced upon irradiation at 355 nm of a gaseous flowing mixture of Cl(2), HCOOH, and N(2). A step-scan Fourier-transform infrared spectrometer coupled with a multipass absorption cell was utilized to monitor the transient spectra of ClCOOH. Absorption bands with origins at 1808.0 and 1328.5 cm(-1) are attributed to the C=O stretching and COH bending modes of t-ClCOOH, respectively; those at 1883.0 and 1284.9 cm(-1) are assigned as the C=O stretching and COH bending modes of c-ClCOOH, respectively. These observed vibrational wavenumbers agree with corresponding values for t-ClCOOH and c-ClCOOH predicted with B3LYP/aug-cc-pVTZ density-functional theory and the observed rotational contours agree satisfactorily with simulated bands based on predicted rotational parameters. The observed relative intensities indicate that t-ClCOOH is more stable than c-ClCOOH by similar to 3 kJ mol(-1). A simple kinetic model is employed to account for the production and decay of ClCOOH.
UV Absorption Cross Sections of ClOOCl Are Consistent with Ozone Degradation Models
(2009-05-08)
Chen, Hsueh-Ying
;
Lien, Chien-Yu
;
Lin, Wei-Yen
;
Lee, Yuan T.
;
Lin, Jim J.
Recently, discrepancies in laboratory measurements of chlorine peroxide (ClOOCl) absorption cross sections have cast doubt on the validity of current photochemical models for stratospheric ozone degradation. Whereas previous ClOOCl absorption measurements all suffered from uncertainties due to absorption by impurities, we demonstrate here a method that uses mass-selected detection to circumvent such interference. The cross sections of ClOOCl were determined at two critical wavelengths (351 and 308 nanometers). Our results are sufficient to resolve the controversial issue originating from the ClOOCl laboratory cross sections and suggest that the highest laboratory estimates for atmospheric photolysis rates of ClOOCl, which best explain the field measurements via current chemical models, are reasonable.
清華男排支柱王良瑋
(2009-05-10)
陳碩峰
;
Department of Communication and Technology
;
傳播與科技學系
訪問清大男排194
熱門偶像劇翻拍正夯
(2009-05-10)
鄭秀芳
;
Department of Communication and Technology
;
傳播與科技學系
0
總編的話
(2009-05-10)
郭大齊
;
Department of Communication and Technology
;
傳播與科技學系
總編的話
勾勒愛與妄想同人誌繪者
(2009-05-10)
楊睿愷
;
Department of Communication and Technology
;
傳播與科技學系
同人誌繪者
黃昏
(2009-05-10)
張雅晴
;
Department of Communication and Technology
;
傳播與科技學系
心情故事
If there is something...
(2009-05-10)
陳怡秀
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Department of Communication and Technology
;
傳播與科技學系
不想休稿
甲型流感H1N1 旋風來襲
(2009-05-10)
林麗珊
;
Department of Communication and Technology
;
傳播與科技學系
甲型流感H1N1
外配找工作養家大不易
(2009-05-10)
林潔
;
Department of Communication and Technology
;
傳播與科技學系
1