Browsing by Issue Date, starting with "2011-08-17"

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Real-Time Vibrational Dynamics in Chlorophyll a Studied with a Few-Cycle Pulse Laser
(2011-08-17)
Du, Juan
;
Teramoto, Takahiro
;
Nakata, Kazuaki
;
Tokunaga, Eiji
;
Kobayashi, Takayoshi
We use a 6.8-fs laser as the light source for broad-band femtosecond pump-probe real-time vibrational spectroscopy to investigate both electronic relaxation and vibrational dynamics of the Q(y)-band of Chl-a at 293 K. More than 25 vibrational modes coupled to the Q(y) transition are observed. Eleven of them have been clarified predominantly due to the excited state, and six of them are concluded to be nearly exclusively resulting from the ground-state wave-packet motion. Moreover, thanks to the broad-band detection over 5000 cm(-1), the modulated signals due to the excited state vibrational coherence are observed on both sides of the 0-0 transition with equal separation. The corresponding nonlinear process has been studied using a three-level model, from which the probe wavelength dependence of the phase of the periodic modulation can be calculated. The probe wavelength dependence of the vibrational amplitude is interpreted in terms of the interaction between the "pump" or "laser," Stokes, and anti-Stokes field intermediated by the molecular vibrations. In addition, an excited state absorption peak at similar to 709 nm has been observed. To the best of our knowledge, this is the first study of broad-band real-time vibrational spectroscopy in Chl-a.
周波数逓倍器装置及びその操作方法
(2011-08-18)
郭建男
;
顏子超
【課題】本発明は、従来の周波数逓倍器による悪い高調波抑圧比を改善し、又、周波数逓倍器からの発振周波数は、他の高調波に妨害されにくいため、周波数逓倍器装置及びその操作方法を提供することを目的とする。【解決手段】本発明の周波数逓倍器装置は、高調波発生器、高調波抑制器及び特定高調波応用装置を含んでいる。前記高調波発生器は、基本周波数を有する入力信号を受信して、第一高調波信号成分及び第二高調波信号成分を含む高調波信号を発生させる。前記高調波抑制器は、前記高調波信号を受信して、前記第一高調波信号成分を抑制し、前記第二高調波信号成分を高める。前記周波数逓倍器装置は、高められた前記第二高調波信号成分を受信する。【選択図】図３（ｂ）
ELECTROSTATIC DISCHARGE PROTECTION CIRCUIT
(2011-08-18)
Ker Ming-Dou
;
Lin Chun-Yu
;
Wang Chang-Tzu
An electrostatic discharge (ESD) protection circuit, suitable for an input stage circuit including a first N channel metal oxide semiconductor (NMOS) transistor, is provided. The ESD protection circuit includes an P channel metal oxide semiconductor (PMOS) transistor and an impedance device, in which the PMOS transistor has a source coupled to a gate of the first NMOS transistor, and a drain coupled to a source of the first NMOS transistor, and the impedance device is coupled between a gate of the PMOS transistor and a first power rail to perform a initial-on ESD protection circuit. The ESD protection circuit formed by the PMOS transistor and the resistor is capable of increasing the turn-on speed of the ESD protection circuit and preventing the input stage circuit from a CDM ESD event.
THIN FILM SOLAR CELL WITH GRADED BANDGAP STRUCTURE
(2011-08-18)
CHANG Chun-Yen
A thin film solar cell with a graded bandgap structure comprises a front contact, a first light absorption layer, a transition layer, a second light absorption layer and a back contact. The first light absorption layer is formed on the front contact, the transition layer is formed on the first light absorption layer, the second light absorption layer is formed on the transition layer, and the back contact is formed on the second light absorption layer, wherein the transition layer has a graded bandgap, which is made by alternating a layer of the first superlattice layers, having a first bandgap, with a layer of the second superlattice layers, having a second bandgap, in a tandem arrangement, based on the condition that the thickness of each layer of the first and the second superlattice layers is varied increasing, decreasing or increasing first and then decreasing.
Red and Green Fluorosulfide Phosphor, Preparation Method and White-Light Emitting Diodes
(2011-08-18)
Chen Teng-Ming
;
Wu Yun-Chen
Novel red and green fluorosulfide phosphors have a chemical formula of (A1-x-yCexBy)SF, wherein A and B are both trivalent metal ions, 0
COLOR DISPLAY DEVICE
(2011-08-18)
Fan Shih-Kang
;
Chiu Cheng-Pu
;
Chen Shih-Chiang
A color display device includes a plurality of pixel display elements and a driving circuit. Each of the pixel display elements includes a plurality of sub-pixel display elements. Each of the sub-pixel display elements includes first and second supports, first and second electrodes attached to inner faces of the first and second supports, respectively, a solution disposed between the first and second electrodes, and particles dispersed in the solution. The particles of the sub-pixel display elements of a same one of the pixel display elements are electrically polarizable by voltage signals supplied by the driving circuit, the voltage signals having the same predetermined driving frequency.
Enhanced Nucleation and Growth of Diamond Film on Si by CVD Using a Chemical Precursor
(2011-08-18)
Tiwari, Rajanish N.
;
Tiwari, Jitendra N.
;
Chang, Li
;
Yoshimura, M.
;
材料科學與工程學系
Nucleation of diamond is of great importance for its growth, and a detailed understanding of the nucleation process is, therefore, desired for Many applications. The pretreatment of the substrate surface may impact the initial growth period. This study demonstrates the synthesis of diamond films by microwave plasma chemical vapor deposition on a Pt/SiO(2)/Si substrate. The Pt particles were deposited on the SiO(2)/Si surface at room temperature, Whereas adamantane was seeded on the SiO(2)/Si surface by ultrasonic treatment:The Pt particles on the SiO(2) surface behave as a catalyst, which adsorb hydrocarbons from adamantane contained plasma and give distinct features of carbon in the early stage deposition The adamantane transforms not only in the nanodiamond phase but also in other carbon phases, which can then act as nuclei for diamond growth. These kinds of phases enhanced the diamond density at partially low temperature deposition. The presence of an oxide intermediate layer betweeen Pt and Si prevents silicidation as well as SiC in diamond deposition.
邊射型高功率雷射二極體結構
(2011-08-21)
盧廷昌
;
陳瓊華
一種邊射型高功率雷射二極體結構，其係具有啁啾(chirp)型周期性分佈之複數模態延展子層，其近場光型會呈現L形，且光場強度高的部分與多重量子井重疊良好，因此可獲得良好的光侷限因子，而且，光場強度低的部分會盡量往n型披覆層延伸，如此可降低邊射型高功率雷射二極體鏡面的光功率密度，並降低垂直發散角，增加此邊射型高功率雷射二極體的壽命。
Effect of high-pressure H2O treatment on elimination of interfacial GeOX layer between ZrO2 and Ge stack
(2011-08-22)
Huang, Chen-Shuo
;
Liu, Po-Tsun
;
光電工程學系
;
顯示科技研究所
;
光電工程研究所
This investigation demonstrates the effect of high-pressure H2O treatment on the elimination of the interfacial germanium suboxide (GeOX) layer between ZrO2 and Ge. The formation of GeOX interlayer increases the gate-leakage current and worsen the controllability of the gate during deposition or thermal cycles. X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy reveal that high-pressure H2O treatment eliminates the interfacial GeOX layer. The physical mechanism involves the oxidation of non-oxidized Zr with H2O and the reduction of GeOX by H-2. Treatment with H2O reduces the gate-leakage current of a ZrO2/Ge capacitor by a factor of 1000. (C) 2011 American Institute of Physics. [doi:10.1063/1.3627187]
Effect of high-pressure H(2)O treatment on elimination of interfacial GeO(X) layer between ZrO(2) and Ge stack
(2011-08-22)
Huang, Chen-Shuo
;
Liu, Po-Tsun
;
光電工程學系
;
顯示科技研究所
;
Department of Photonics
This investigation demonstrates the effect of high-pressure H(2)O treatment on the elimination of the interfacial germanium suboxide (GeO(X)) layer between ZrO(2) and Ge. The formation of GeO(X) interlayer increases the gate-leakage current and worsen the controllability of the gate during deposition or thermal cycles. X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy reveal that high-pressure H(2)O treatment eliminates the interfacial GeO(X) layer. The physical mechanism involves the oxidation of non-oxidized Zr with H(2)O and the reduction of GeO(X) by H(2). Treatment with H(2)O reduces the gate-leakage current of a ZrO(2)/Ge capacitor by a factor of 1000. (C) 2011 American Institute of Physics. [doi:10.1063/1.3627187]
交大e-News第100期
(2011-08-22)
Secretariat
;
國立交通大學秘書室
Group authentication method
(2011-08-23)
Chen Yu-Wen
;
Wang Jui-Tang
;
Tseng Chien-Chao
A group authentication method adaptable to a communication system is disclosed. The communication system includes a user group, a serving network, and a home network. The user group includes at least one mobile station. The home network pre-distributes a group authentication key to itself and all the mobile stations in the same user group and generates a mobile station authentication key for each mobile station. The home network generates a group list for recording related information of the user group. The home network has a database for recording the group list. The serving network has a database for recording the group list and a group authentication data received from the home network. The group authentication method includes following steps. The serving network performs an identification action to a mobile station. The communication system performs a full authentication action or a local authentication action according to the result of the identification action.
Evidence for s-wave superconductivity in noncentrosymmetric Re24Nb5 from Nb-93 NMR measurements
(2011-08-25)
Lue, C. S.
;
Su, T. H.
;
Liu, H. F.
;
Young, Ben-Li
;
電子物理學系
We report a Nb-93 nuclear magnetic resonance (NMR) study on the noncentrosymmetric superconductor Re24Nb5. Below the superconducting temperature T-c(H), the spin susceptibility probed by the Nb-93 NMR Knight shift gradually decreases with lowering temperature, accompanied by the broadening of the resonance spectrum. Such behavior is commonly observed in the BCS-type superconductors. The Nb-93 NMR spin-lattice relaxation rate (1/T-1) shows a well-defined coherence peak just below T-c(H), followed by a marked decrease with further decreasing temperature. Moreover, the 1/T-1 data in the superconducting state were found to obey a single exponential expression, yielding a nodeless gap Delta/kB = 10.3 K. This value gives the ratio of 2 Delta/kBT(c)(H) = 3.55, that is almost identical with the value of 3.5 predicted from BCS theory. On these bases, we conclude that the noncentrosymmetric Re24Nb5 compound can be characterized as a weakly coupled BCS-type superconductor.
Evidence for s-wave superconductivity in noncentrosymmetric Re(24)Nb(5) from (93)Nb NMR measurements
(2011-08-25)
Lue, C. S.
;
Su, T. H.
;
Liu, H. F.
;
Young, Ben-Li
;
電子物理學系
We report a (93)Nb nuclear magnetic resonance (NMR) study on the noncentrosymmetric superconductor Re(24)Nb(5). Below the superconducting temperature T(c)(H), the spin susceptibility probed by the (93)Nb NMR Knight shift gradually decreases with lowering temperature, accompanied by the broadening of the resonance spectrum. Such behavior is commonly observed in the BCS-type superconductors. The (93)Nb NMR spin-lattice relaxation rate (1/T(1)) shows a well-defined coherence peak just below T(c)(H), followed by a marked decrease with further decreasing temperature. Moreover, the 1/T(1) data in the superconducting state were found to obey a single exponential expression, yielding a nodeless gap Delta/kB = 10.3 K. This value gives the ratio of 2 Delta/kBT(c)(H) = 3.55, that is almost identical with the value of 3.5 predicted from BCS theory. On these bases, we conclude that the noncentrosymmetric Re(24)Nb(5) compound can be characterized as a weakly coupled BCS-type superconductor.
Novel approach towards 2-substituted aminobenzimidazoles on imidazolium ion tag under focused microwave irradiation
(2011-08-26)
Chanda, Kaushik
;
Maiti, Barnali
;
Chung, Wen-Sheng
;
Sun, Chung-Ming
;
應用化學系
We have developed an efficient, parallel synthesis of 2-substituted aminobenzimidazoles via intramolecular ring closing reactions of imidazolium ion tag immobilized o-phenylenediamine with various isothiocyanates. The methodology is based on the attachment of 4-fluoro-3-nitro benzoic acid into the imidazolium ion tag, which enables the S(N)Ar reactions with different amines followed by neutral reduction to furnish o-phenylenediamines under microwave irradiation. The substituted isothiocyanates are reacted with o-phenylenediamines to form monothiourea, which is further activated by methyl iodide to undergo desulfurization in one pot manner. The ionic liquid bound 2-substituted aminobenzimidazoles were finally cleaved from the support with sodium methoxide to generate target compounds in good yields and high purities with two points of structural diversity. This synthetic protocol has promising features of extremely short reaction time, operational simplicity, good yields, as well as widespread applications, leading to a facile and straightforward admittance to structurally diverse 2-substituted aminobenzimidazole analogues with potential bioactivities. (C) 2011 Elsevier Ltd. All rights reserved.
Photoactivation studies of zinc protoporphyrin-myoglobin system and its application for light-chemical energy conversion
(2011-08-28)
Wu, Tung-Kung
;
生物科技學系
;
Department of Biological Science and Technology
Genotoxicity of safrole oxide in HEPG2 cells and in mice
(2011-08-28)
Chiang, S.
;
Lee, P.
;
Shen, L.
;
Huang, H.
;
Chung, W.
Organic photovoltaics incorporating new fulleroisoquinolinones and fulleroindolines as n-type materials: Syntheses and performance studies
(2011-08-28)
Chuang, Shih-Ching
;
Chen, Chih-Ping
;
應用化學系
;
Department of Applied Chemistry
Three-component and alpha-Michael reaction of phosphines with En-ynes and aldehydes: Formation of gamma-lactones featuring alpha-phosphorus ylides
(2011-08-28)
Deng, Jie-Cheng
;
Chuang, Shih-Ching
;
應用化學系
;
Department of Applied Chemistry
Assembling and crystallization of amino acids and proteins by intense laser irradiation in solution
(2011-08-28)
Masuhara, Hiroshi
;
Sugiyama, Teruki
;
Yuyama, Ken-ichi
;
Uwada, Takayuki
;
Miura, Atsushi