Browsing by Issue Date, starting with "2012-09-17"

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Phonon dynamics in CuxBi2Se3 (x=0, 0.1, 0.125) and Bi2Se2 crystals studied using femtosecond spectroscopy
(2012-09-17)
Chen, H. -J.
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Wu, K. H.
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Luo, C. W.
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Uen, T. M.
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Juang, J. Y.
Phonon dynamics in Bi, Bi2Se2, and CuxBi2Se3 (x=0, 0.1, 0.125) single crystals was investigated using femtosecond pump-probe spectroscopy. Two damped oscillations in measured transient reflectivity changes were observed, respectively, attributed to coherent optical and acoustic phonons. The frequency shift of the phonon modes in Bi-rich Bi2Se2 crystals indicates the intercalation of the additional Bi atoms into the Bi2Se3 matrix and formation of the Bi-2 layer between the quintuple layers (QLs). The deformation of QLs in CuxBi2Se3 crystals was also found. These phonon dynamics results suggest that Cu atoms in CuxBi2Se3 crystals are predominantly intercalated between pair of QLs. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4754005]
Geometrical impact on the optical polarization of droplet epitaxial quantum dots
(2012-09-17)
Liao, Yu-Huai
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Liao, Chien-Chih
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Ku, Chih-Hao
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Chang, Yu-Chen
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Cheng, Shun-Jen
We report on experimental and theoretical investigations of the optical anisotropy of GaAs/AlGaAs quantum dots grown by droplet epitaxy. With in situ annealing in the growth, the shape of quantum dots is systematically controlled from a tall and laterally symmetric shape to a flat and laterally elongated one. Photoluminescence spectroscopy demonstrates an uncommon observation: the more elongated the quantum dots, the lower the degree of linear polarization. Theoretical analysis based on a four-band k center dot p theory reveals a substantial impact of vertical confinement on the valence heavy-hole and light-hole mixing, which leads to the enhancement of polarization anisotropy for taller quantum dots. The influence of Coulomb interactions on polarization anisotropy is studied by using the partial configuration interaction method, and is shown to reduce the polarization anisotropy through the mixing of single-particle configurations with different symmetries.
Thermally switchable adhesions of polystyrene-block-poly (n-isopropylacrylamide) copolymer pillar array mimicking climb attitude of geckos
(2012-09-17)
Chen, Jem-Kun
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Wang, Jing-Hong
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Chang, Jia-Yaw
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Fan, Shih-Kang
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材料科學與工程學系
Inspired by the gecko foot pad, we fabricated polystyrene-block-poly(N-isopropylacrylamide) (PS-b-PNIPAAm) copolymer pillar array to mimic climbing attitude of a gecko, alternately attach to and detach from a surface. The pillar array structure of the PS segment significantly enhances both of the hydrophilic and hydrophobic property of PNIPAAm segment tips at 25 and 50 degrees C, respectively, which could generate alternating adhesive forces of approximately 120 and 11 nN. The dramatic change in adhesive and friction force difference at 25 and 50 degrees C may guide the design of bio-inspired artificial analogues, which could approach gecko's climbing behavior. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4754135]
In vivo formation of N7- guanine DNA adduct by safrole 2 ',3 '-oxide in mice
(2012-09-18)
Shen, Li-Ching
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Chiang, Su-Yin
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Lin, Ming-Huan
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Chung, Wen-Sheng
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Wu, Kuen-Yuh
Safrole, a naturally occurring product derived from spices and herbs, has been shown to be associated with the development of hepatocellular carcinoma in rodents. Safrole 2',3'-oxide (SFO), an electrophilic metabolite of safrole, was shown to react with DNA bases to form detectable DNA adducts in vitro, but not detected in vivo. Therefore, the objective of this study was to investigate the formation of N7-(3-benzo[1,3] dioxol-5-yl-2-hydroxypropyl) guanine ( N7 gamma-SFO-Gua) resulting from the reaction of SFO with the most nucleophilic site of guanine in vitro and in vivo with a newly developed isotope-dilution high performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method. N7 gamma-SFO-Gua and [N-15(5)]-N7-(3-benzo[1,3] dioxol-5-yl-2-hydroxypropyl) guanine ([N-15(5)]-N7 gamma-SFO-Gua) were first synthesized, purified, and characterized. The HPLC-ESI-MS/MS method was developed to measure N7 gamma-SFO-Gua in calf thymus DNA treated with 60 mu mol of SFO for 72 h and in urine samples of mice treated with a single dose of SFO (30 mg/kg body weight, intraperitoneally). In calf thymus DNA, the level of N7 gamma-SFO-Gua was 2670 adducts per 106 nucleotides. In urine of SFO-treated mice, the levels of N7 gamma- SFO-Gua were 1.02 +/- 0.14 ng/mg creatinine (n = 4) on day 1, 0.73 +/- 0.68 ng/mg creatinine (n = 4) on day 2, and below the limit of quantitation on day 3. These results suggest that SFO can cause in vivo formation of N7 gamma-SFO-Gua, which may then be rapidly depurinated from the DNA backbone and excreted through urine. (c) 2012 Elsevier Ireland Ltd. All rights reserved.
Dynamic calibration method for single and multiple video capture devices
(2012-09-18)
Chen I-Hsien
;
Wang Sheng-Jyh
The present invention discloses a dynamic calibration method for a single and multiple video capture devices. The present invention can acquire the variations of the pan angle and tilt angle of a single video capture device according to the displacement of the feature points between successive images. For a plurality of video capture devices, the present invention includes the epipolar-plane constraint between a plurality of video capture devices to achieve the goal of dynamical calibration. The calibration method in the present invention does not require specific calibration patterns or complicated correspondence of feature points, and can be applied to surveillance systems with wide-range coverage.
Gate controlled field emission triode and process for fabricating the same
(2012-09-18)
Lee Chia-Ying
;
Li Seu-Yi
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Lin Pang
;
Tseng Tseung-Yuan
This invention relates to a process for fabricating ZnO nanowires with high aspect ratio at low temperature, which is associated with semiconductor manufacturing process and a gate controlled field emission triode is obtained. The process comprises providing a semiconductor substrate, depositing a dielectric layer and a conducting layer, respectively, on the semiconductor substrate, defining the positions of emitter arrays on the dielectric layer and conducting layer, depositing an ultra thin ZnO film as a seeding layer on the substrate, growing the ZnO nanowires as the emitter arrays by using hydrothermal process, and etching the areas excluding the emitter arrays, then obtaining the gate controlled field emission triode.
交大e-News第126期
(2012-09-20)
Secretariat
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國立交通大學秘書室
On-Chip Noise Filter Circuit
(2012-09-20)
Ker Ming-Dou
;
Yen Cheng-Cheng
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Chen Tung-Yang
A noise filter circuit for an IC is provided. The noise filter circuit comprises a decoupling unit coupled to a power pad of the IC and a current amplifier circuit coupled to the decoupling unit and the power pad of the IC. The decoupling unit generates a first current in response to a transient voltage being on the power pad of the IC. The current amplifier circuit drains a second current from the power pad of the IC according to the first current.
Production of H and O(P-3) Atoms in the Reaction of CH2 with O-2
(2012-09-20)
Lee, Pei-Fang
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Matsui, Hiroyuki
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Chen, Wei-Yu
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Wang, Niann-Shiah
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應用化學系
The reaction CH2 + O-2 -> 4 products has been studied by using atomic resonance absorption spectrometry (ARAS) of H and O(P-3) atoms behind reflected shock waves over 1850-2050 K and 2.1-1.7 atm. Measurements of [H] and [O] are conducted using mixtures of highly diluted CH2I2 (0.2 and 0.4 ppm) with excess O-2 (100 and 262 ppm) in Ar; comparative measurement of [H] in the 0.2 and 0.4 ppm CH2I2 + 300 ppm H-2 mixture has been conducted simultaneously to confirm the initial concentration of CH2. The apparent reaction rate of CH2 + O-2 (k(2)'), including the contributions of (CH2)-C-3 + O-2 -> products (2) and (CH2)-C-1 + O-2 -> products (3), has been measured from the evolutions of [H] and [O] and summarized as k(2)'/cm(3) molecule(-1) s(-1) = (1.90 +/- 0.31) x 10(-11). The contribution of (CH2)-C-1 + O-2 reaction on the measured k(2)' has been evaluated as 0.15 +/- 0.04, with an assumption that k(3) is independent of temperature and given by the result measured at room temperature [Langford, A. O.; Petek, H.; Moore, C. B. J. Chem. Phys. 1983, 78, 6650-6659]. The net rate for the (CH2)-C-3 + O-2 reaction is given as k(2)/cm(3) molecule(-1) s(-1) = (1.69 +/- 0.31) x 10(-11). The result on k(2) in this study is found to be consistent with the extrapolation of the previous work at lower temperature range of 295-600 K. [Vinckler, C.; Debruyn, W. J. Phys. Chem. 1979, 83, 2057-2062]; these results can be summarized as k(2)/cm(3) molecule(-1) s(-1) = 2.74 x 10(-11) exp(-874/T), (T = 295-2050 K). The apparent production yields of H and O atoms for the reaction channels (CH2)-C-1,3 + O-2 -> H + products (2a, 3a) and (1)'(CH2)-C-3 + O-2 -> O(P-3) + products (2h, 3b) have been evaluated as phi(2a)' = 0.59 +/- 0.06 and phi(2b)' = 0.23 +/- 0.06, respectively. The contributions of (CH2)-C-1 + O-2 reaction on measured phi(2a)' and phi(2b)' are indicated to be minor; the net branching fractions for the (CH2)-C-3+O-2 reaction are estimated as phi(2a) = 0.58 +/- 0.06 and phi(2b) = 0.25 +/- 0.06. No obvious temperature dependence is indicated in the measured rate constant nor in the branching fractions of H and 0 atoms. The mechanism of the reaction of CH2 with O-2 is discussed based on the result of the present study together with those of the previous theoretical/experimental studies.
ENHANCEMENT-MODE HIGH-ELECTRON-MOBILITY TRANSISTOR AND THE MANUFACTURING METHOD THEREOF
(2012-09-20)
CHANG EDWARD YI
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Chang Chia-Hua
;
Lin Yueh-Chin
This invention discloses an enhancement-mode high-electron-mobility transistor and the manufacturing method thereof. The transistor comprises an epitaxial buffer layer on a substrate, a source and drain formed in the buffer layer, a PN-junction stack formed on the buffer layer and located between the source and drain, and a gate formed on the PN-junction stack, wherein the PN-junction stack is composed of alternating layers of a P-type semiconductor and an N-type semiconductor.
VERTICAL ELECTRO-OPTICAL COMPONENT AND METHOD OF FABRICATING THE SAME
(2012-09-20)
Zan Hsiao-Wen
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Meng Hsin-Fei
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Tsai Wu-Wei
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Chao Yu-Chiang
A vertical electro-optical component and a method for forming the same are provided. The vertical electro-optical component includes a substrate, a first electrode layer formed on the substrate, a patterned insulating layer formed on the first electrode layer, a metal layer formed on the patterned insulating layer, a semiconductor layer formed on the first electrode layer, and a second electrode layer formed on the semiconductor layer, wherein the semiconductor layer encapsulates the patterned insulating layer and the metal layer. The vertical electro-optical component thus has a low operational voltage of a vertical transistor and a high reaction speed of a photo diode, and may be used to form light-emitting transistors.
ON-CHIP ELECTRONIC DEVICE AND METHOD FOR MANUFACTURING THE SAME
(2012-09-20)
CHENG YU-TING
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CHAO TZU-YUAN
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CHEN KUAN-MING
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HSU HSIN-FU
The present invention relates to an on-chip electronic device and a method for manufacturing the same. The on-chip electronic device according to the present invention comprises a substrate, a porous layer, a plurality of magnetic bodies, and an electronic member layer. The porous layer is disposed on the substrate and has a plurality of voids; each of the plurality of magnetic bodies is disposed in the plurality of voids, respectively; and the electronic member layer is disposed on one side of the porous layer, such as upper side of or lower sider of the porous layer. Because the plurality of magnetic bodies is used as the core of the inductance, the inductance is increased effectively and the area of the on-chip electronic device is reduced. Besides the manufacturing method according to the present invention is simple and compatible with the current CMOS process, the manufacturing cost can be lowered.
ＧＰＳ追蹤系統
(2012-09-21)
吳炳飛
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陳盈翰
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陳昭榮
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高志忠
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黃柏嘉
本發明揭露一種GPS追蹤系統，其包含有：一追蹤定位裝置；一伺服裝置；一定位顯示裝置；以及一資料庫。由於該追蹤定位裝置僅在連結網際網路時傳送一次之網際網路通訊協定資料及一認證資料，並在定位顯示裝置觀看時才傳送定位資料，故可節省頻寬。
給我一條船航向文字海
(2012-09-23)
鄭乃文
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Department of Communication and Technology
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傳播與科技學系
在生活中要求自己，主動爭取生命裡的幸運。
新手上路囉!!!加油!!!
(2012-09-23)
蘇品勻
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Department of Communication and Technology
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傳播與科技學系
看完學長姊喀報後的心得與提問
新手上路
(2012-09-23)
鄭姿筠
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Department of Communication and Technology
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傳播與科技學系
以即將成為喀報記者之人的身分，說說心中的疑惑和自我的期許。
喀報之旅我來了
(2012-09-23)
王紹容
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Department of Communication and Technology
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傳播與科技學系
喀報羽翼漸豐的歷程
(2012-09-23)
林慰
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Department of Communication and Technology
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傳播與科技學系
雖然喀報被學長姐們形容的很可怕，但是我相信一年喀報記者的磨練，可以讓我成為更稱職的傳科人。
新方向新旅程
(2012-09-23)
薛世如
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Department of Communication and Technology
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傳播與科技學系
循著學長姊的經驗，走出自己的路。
新手上路
(2012-09-23)
王蒂鷹
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Department of Communication and Technology
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傳播與科技學系