Browsing by Issue Date, starting with "2012-04-10"

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Effect of Ionic Liquid on Structure and Properties of Polysquaraines
(2012-04-10)
Ho, Mei-Chan
;
Chao, Ching-Hsun
;
Chen, Chun-Hua
;
Wu, Ren-Jye
;
Whang, Wha-Tzong
Polycondensation of 4-bis[2-(1-methylpyrrol-2-yl)vinyl]-2,5-didodecyloxybenzene and squaric acid yielded the polysquaraine SQ with two isomeric subunits-1,3-addition (zwitterionic) and 1,2-addition (diketonic) moieties in the main chain structure. The former featured a C-O/C=O infrared (IR) absorption frequency at 1622 cm(-1); the latter, a C=O signal at 1716 cm(-1). Traditional synthesis yielded SQ as a powder with metallic luster that could not be cast as a polymer film from solution. When the ionic liquid [Oct(3)NMe][TfO] (IL) was present in the cosolvent of BuOH and benzene (1:3), however, the resulting SQI(x) polymers (x = 0.01-5 wt %) did not precipitate from solution, making it possible to cast continuous free-standing films with a large area (>1 X 1 cm(2)). A greater content of IL in the solution favored the formation of the 1,3-addition zwitterionic subunits in the SQI(x) polymer main chains, thereby changing the physical and optical properties of the polysquaraine, as evidenced in IR and optical absorption spectra. The features in the UV-Vis-NIR absorption spectra of SQ and SQL(x) were dependent on the IL concentration and the nature of the solvent. Among our synthesized SQI(x) polymers, SQI(0.01) and SQI(0.1) formed flexible free-standing films with metallic luster, smooth surfaces, and good semiconductivities (2.27 x 10(-5) and 4.74 x 10(-5) S/cm, respectively). X-ray diffraction patterns revealed that the presence of IL in the polymerization medium increased the SQI(x) interchain packing distance. SQI(0.01), and SQI(0.1) possessed thermal stabilities comparable with that of SQ. Our successful use of IL in the preparation of SQI(x) polymers appears to have great potential for application in ionic liquid-related organic or polymeric preparation and processing.
A New Supramolecular Hole Injection/Transport Material on Conducting Polymer for Application in Light-Emitting Diodes
(2012-04-10)
Chu, Yu-Lin
;
Cheng, Chih-Chia
;
Yen, Ying-Chieh
;
Chang, Feng-Chih
;
應用化學系
利用數位激發訊號來準確測量放大器開路增益之裝置
(2012-04-11)
洪浩喬
本發明提供一種可接收數位激發訊號並可準確量測放大器開路增益之裝置，其包含：數位電荷轉換器(DCC)、電荷積分器、類比/數位轉換器(ADC)、控制邏輯電路、以及算術邏輯單元(ALU)。其中該數位電荷轉換器(DCC)與該電荷積分器係由複數個開關、一個以上的取樣電容器、一個以上的積分電容器與一個單端(single－ended)或差動(differential)輸出之待測試運算放大器(OPAUT)等元件所構成。該數位電荷轉換器(DCC)、該電荷積分器、該類比/數位轉換器(ADC)受該控制邏輯電路所產生之控制訊號所控制，構成一個可接收一個以上數位激發訊號之一階三角積分調變器。該算術邏輯單元(ALU)根據該(等)數位激發訊號與該一階三角積分調變器的數位輸出計算出該單端或差動輸出之待測試運算放大器的開路增益。或者，該控制邏輯電路更可接收一數位模式訊號，且當該控制邏輯電路接收之數位模式訊號為測試模式時，該(等)取樣電容器、該(等)積分電容器、該待測試運算放大器、該類比/數位轉換器(ADC)、以及複數個開關受該控制邏輯電路所產生之複數個控制訊號所控制，重構成該可接收數位輸入激發訊號之一階三角積分調變器，並利用該算術邏輯單元計算出該單端或差動輸出之待測試運算放大器之開路增益。
饗宴光影：從《陰翳禮讚》看谷崎文學的感官藝術
(2012-04-11)
蕭幸君
;
開放教育推動中心
;
Open Education Office
課程首頁本課程是由交通大學新文藝復興閱讀計畫提供。 96 年 8 月當各大學紛紛摩拳擦掌準備迎接新生的同時，交通大學校長吳重雨則因為一則來自於七月份泰晤士報，有關於英國首相布朗公布其夏日讀書清單的新聞中，看到了他對知識的尊重。在這同時，吳重雨校長也思考著，要如何為學生準備追求知識的環境和激發他們對知識的尊重與喜愛。台積電張忠謀董事長曾陳述他 18 歲進入哈佛那一年，博覽文史哲理工經典群籍，至此奠定了他求知的基礎，並借海明威名言，將其改為「哈佛這一年為人生可帶走的盛宴。」吳重雨校長以張董事長的學習為借鏡，認為學生固然能藉由自我閱讀的方式學習到豐沛的知識，但透過名人、大師親臨現場地介紹經典書籍，更能加深學子們對於書籍的認識與興趣，這也是「新文藝復興閱讀計劃」 ( 以下簡稱 : 「經典名著選讀」 ) 活動展開籌劃的緣由。於是，吳重雨校長便積極敦請「交大通識教育委員會」，接手籌備本計劃的相關活動，而該中心也成為實際施行本計畫的策動、開課以及認證單位。至此，期許交大學子藉由閱讀、聽講來提昇人文素養、開拓視野的「新文藝復興閱讀計劃」，就此展開。
GATE OXIDE BREAKDOWN-WITHSTANDING POWER SWITCH STRUCTURE
(2012-04-12)
YANG Hao-I
;
Chuang Ching-Te
;
Hwang Wei
The present invention proposes a gate oxide breakdown-withstanding power switch structure, which is connected with an SRAM and comprises a first CMOS switch and a second CMOS switch respectively having different gate-oxide thicknesses or different threshold voltages. The CMOS switch, which has a normal gate-oxide thickness or a normal threshold voltage, provides current for the SRAM to wake up the SRAM from a standby or sleep mode to an active mode. The CMOS switch, which has a thicker gate-oxide thickness or a higher threshold voltage, provides current for the SRAM to work in an active mode. The present invention prevents a power switch from gate-oxide breakdown lest noise margin, stabilization and performance of SRAM be affected.
Adiabatically slow and adiabatically fast driven ratchets
(2012-04-12)
Rozenbaum, V. M.
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Makhnovskii, Yu. A.
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Shapochkina, I. V.
;
Sheu, S. -Y.
;
Yang, D. -Y.
We revisit two known models of deterministically driven ratchets, which exhibit high energetic efficiency, with the goal to uncover similarities and differences in the principles of their operation. Both the models rely on adiabaticity of the potential change process, however, the adiabaticity that we deal with in the two cases is of different types, slow and fast. It is shown that in the former (latter) case the drift velocity is an even (odd) functional of the potential, with the notable consequence that for the adiabatically slow driven ratchet the necessary symmetry breaking occurs only due to time-dependent parametric perturbations, while the spatial asymmetry of the potential is a mandatory condition for the adiabatically fast driven ratchet to operate. To treat energetic characteristics, the models are restated in terms of traveling potential ratchets. With such an approach, we find that in these cases (i) the conditions of high energetic efficiency to be reached are similar, and (ii) the symmetry properties of the kinetic coefficients are different. Based on our results, a strategy for designing efficient Brownian motors is suggested.
VERTICAL TYPE SENSOR
(2012-04-12)
Zan Hsiao-Wen
;
Meng Hsin-Fei
;
Dai Ming-Zhi
;
Chao Yu-Chiang
The present invention provides a vertical type sensor, including a substrate; a first electrode formed on the substrate; a sensing layer formed on the first electrode layer and reactive to a target substance, wherein the first electrode layer is interposed between the substrate and the sensing layer; and a second electrode layer formed on the sensing layer and having a plurality of openings, wherein the sensing layer is interposed between the first electrode layer and the second electrode layer, and the target substance contacts the sensing layer via the plurality of openings. The vertical type sensor of the present invention provides instant, sensitive and rapid detection.
Optoelectronic Properties of Density-Controlled ZnO Nanopillar Arrays
(2012-04-12)
Chang, Yuan-Ming
;
Huang, Jheng-Ming
;
Lin, Chih-Ming
;
Lee, Hsin-Yi
;
Chen, San-Yuan
An effective method of controlling the density of ZnO nanopillars (ZnO-NPs) by using the self-assembled silver nanoislands as the growth catalyst is demonstrated. We were able to vary the density of the ZnO-NPs to within the range of similar to 10-30 mu m(-2) by properly manipulating the size distribution of the silver nanoislands partially covering the Si substrates. Continuous silver film can also be used as the catalyst to facilitate the growth of ZnO islands and pillars on Si substrates, albeit with much less control of the resultant density and morphological appearances. The field emission measurements indicate that the performance of field emission for ZnO-NPs can be. improved markedly by reducing the density of the ZnO-NPs. The turn-on field of the low-density ZnO-NPs was as low as 2.39 V/mu m with a corresponding current density of 10 mu A/cm(2) and a field enhancement factor (beta value) of similar to 3500. The enhancement of field emission characteristics is attributed to the much reduced field screen effect by properly controlled density of the ZnO-NPs.
Fabrication and resistive switching characteristics of high compact Ga-doped ZnO nanorod thin film devices
(2012-04-13)
Yao, I-Chuan
;
Lee, Dai-Ying
;
Tseng, Tseung-Yuen
;
Lin, Pang
;
材料科學與工程學系
This study investigates the resistive switching behavior of Ga-doped ZnO (GZO) nanorod thin films with various Ga/Zn molar ratios. Vertically well-aligned and uniform GZO nanorod thin films were successfully grown on Au/Ti/SiO2/p-Si substrates using an aqueous solution method. X-ray diffraction (XRD) results indicate that GZO nanorods have [0001] highly preferred orientation. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations show the formation of highly ordered and dense nanorod thin films. These compact GZO nanorod thin films can be used to make resistive switching memory devices. Such memory devices can be reversibly switched between ON and OFF states, with a stable resistance ratio of ten times, narrow dispersion of ON and OFF voltages, and good endurance performance of over 100 cycles. The resistive switching mechanism in these devices is related to the formation and rupture of conducting filaments consisting of oxygen vacancies, occurring at interfaces between GZO nanorods (grain boundaries). Results show that the resulting compact GZO nanorod thin films have a high potential for resistive memory applications.
Synthesis of Main-Chain Metallo-Copolymers Containing Donor and Acceptor Bis-Terpyridyl Ligands for Photovoltaic Applications
(2012-04-13)
Padhy, Harihara
;
Ramesh, Mohan
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Patra, Dhananjaya
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Satapathy, Rudrakanta
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Pola, Murali Krishna
Two random (ZnII-based P1P2) and two alternating (RuII-based P3P4) metallo-copolymers containing bis-terpyridyl ligands with various central donor (i.e., fluorene or carbazole) and acceptor (i.e., benzothiadiazole) moieties were synthesized. The effects of electron donoracceptor interactions with metal (ZnII and RuII) ions on their thermal, optical, and electrochemical properties were investigated. Because of the strong ICT transitions between donor and acceptor ligands in both ZnII- and RuII-based metallo-coplymers and MLCT transitions in RuII-based metallo-coplymers, the absorption spectra covered a broad range of 260750 nm with the band gaps of 1.571.77 eV. In addition, the introduction of RuII-based metallo-coplymer P4 mixed with PC60BM as an active layer of the BHJ solar cell device exhibited the highest PCE value up to 0.90%.
Applications of parametric processes to high-quality multicolour ultrashort pulses, pulse cleaning and CEP stable sub-3fs pulse
(2012-04-14)
Kobayashi, Takayoshi
;
Liu, Jun
;
Okamura, Kotaro
;
電子物理學系
;
Department of Electrophysics
Our recent experimental results of three methods related to and useful for the generation of attosecond pulses are summarized. The pulses obtained by all of them have high qualities in terms of phase, temporal, spectral and spatial properties which are based on the physical principles associated with the parametric processes. First, carrier-envelope phase (CEP) stable sub-5 fs and sub-3 fs pulses by non-collinear optical parametric amplification (NOPA) in the near-infrared and visible spectral range will be described. The mechanism of the passive CEP stabilization is described. Passively stabilized idler and its second harmonic (SH) pulses from NOPAs are compressed to sub-5fs and sub-3fs, respectively. Compression of the idler output from a NOPA and its SH is attained with a specially designed characterization method during the compression. Second, generation of multicolour pulses by the cascaded four-wave mixing process in bulk media is discussed. As short as 15-fs multicoloured femtosecond pulses are obtained with two similar to 40 fs pulses incident to a fused-silica glass plate by this method. These broadband multicolour sidebands are expected to provide single-cycle or sub-fs pulses after the Fourier synthesis. Third, a new technique based on self-diffraction in the Kerr medium is used to clean and shorten the femtosecond laser pulse. The cleaned pulse with high temporal contrast is expected to be used as a seed for a background-free petawatt laser system and then used as the laser source for high-energy attosecond pulse generation in a solid target. The mechanisms of CEP stabilization, pulse spectral smoothening and pulse contrast enhancement are comparatively discussed.
Franck-Condon simulation of vibrationally resolved optical spectra for zinc complexes of phthalocyanine and tetrabenzoporphyrin including the Duschinsky and Herzberg-Teller effects
(2012-04-14)
Guo, Meiyuan
;
He, Rongxing
;
Dai, Yulan
;
Shen, Wei
;
Li, Ming
High resolved absorption and fluorescence spectra of zinc complexes of phthalocyanine (ZnPc) and tetrabenzoporphyrin (ZnTBP) in the region of Q states were reported. Few theoretical investigations were performed to simulate the well-resolved spectra and assigned the vibrational bands of the large molecules, especially for high symmetrical characteristic molecules, on account of the difficulties to optimize the excited states and analyze a large number of final vibrational-normal modes. In the present work, the S-0 <-> S-1 absorption and fluorescence spectra (that is, the Q band) of ZnPc and ZnTBP were simulated using time-dependent density functional theory with the inclusions of Duschinsky and Herzberg-Teller contributions to the electronic transition dipole moments. The theoretical results provide a good description of the optical spectra and are proved to be in excellent agreement with experimental spectra in inert-gas matrices or in supersonic expansion. This study focused attentions on the optical spectral similarities and contrasts between ZnPc and ZnTBP, in particular the noticeable Duschinsky and Herzberg-Teller effects on the high-resolved absorption and fluorescence spectra were considered. Substitution of meso-tetraaza on the porphyrin macrocycle framework could affect the ground state geometry and alter the electron density distributions, the orbital energies that accessible in the Q band region of the spectrum. The results were used to help interpret both the nature of the electronic transitions in Q band region, and the spectral discrepancies between phthalocyanine and porphyrin systems. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3703310]
A Structured Quasi-Arnoldi procedure for model order reduction of second-order systems
(2012-04-15)
Li, Yung-Ta
;
Bai, Zhaojun
;
Lin, Wen-Wei
;
Su, Yangfeng
;
應用數學系
Existing Krylov subspace-based structure-preserving model order reduction methods for the second-order systems proceed in two stages. The first stage is to generate a basis matrix of the underlying Krylov subspace. The second stage is to employ an explicit subspace projection to obtain a reduced-order model with a moment-matching property. An open problem is how to avoid explicit projection so that it will be efficient for truly large scale systems. In addition, it is also desired that a structure-preserving reduced system of order n matches maximum 2n moments. In this paper we propose a new procedure to compute a so-called Structured Quasi-Arnoldi (SQA) decomposition. Once the SQA decomposition is computed, a structure-preserving reduced-order model can be defined immediately from the decomposition without the explicit subspace projection. Furthermore, the reduced model of order n matches maximum 2n moments. Numerical examples demonstrate that the transpose-free SQA-based reduced model is compatible with the two-sided structure-preserving explicit projection methods and is more accurate than the one-sided structure-preserving explicit projection methods due to the higher number of matched moments. (C) 2011 Elsevier Inc. All rights reserved.
On the structure of multi-layer cellular neural networks
(2012-04-15)
Ban, Jung-Chao
;
Chang, Chih-Hung
;
Lin, Song-Sun
;
應用數學系
;
Department of Applied Mathematics
Let Y subset of {-1, 1}(Z infinity xn) be the mosaic solution space of an n-layer cellular neural network. We decouple Y into n subspaces, say Y-(1), Y-(2), ... , Y-(n), and give a necessary and sufficient condition for the existence of factor maps between them. In such a case, Y-(i) is a sofic shift for 1 <= i <= n. This investigation is equivalent to study the existence of factor maps between, two sofic shifts. Moreover, we investigate whether Y-(i) and Y-(j) are topological conjugate, strongly shift equivalent, shift equivalent, or finitely equivalent via the well-developed theory in symbolic dynamical systems. This clarifies, in a multi-layer cellular neural network, each layer's structure. As an extension, we can decouple Y into arbitrary k-subspaces. where 2 <= k <= n, and demonstrates each subspace's structure. (C) 2012 Elsevier Inc. All rights reserved.
Optical trapping and polarization-controlled scattering of dielectric spherical nanoparticles by femtosecond laser pulses
(2012-04-15)
Usman, Anwar
;
Chiang, Wei-Yi
;
Masuhara, Hiroshi
;
應用化學系
;
應用化學系分子科學碩博班
We present optical trapping behavior of 50-nm-sized polystyrene beads, suspended in water medium, by femtosecond pulsed laser beam. In addition to a higher number of nanoparticles trapped at the focal spot by the ultrashort laser pulses compared with that by continuous-wave laser, the nanoparticles are scattered out of the focal spot by the laser pulses to the surrounding area. The scattered particles form a partially opened folding fan-shaped bright locus in two opposite directions, in an alternating manner, perpendicular to the laser polarization. To understand those phenomena, we analyzed radiation (gradient and scattering) force of femtosecond laser pulses and their temporal force exerted on the dielectric spherical nanoparticles by taking into account the impulsive peak power and the axial component of electric light field produced by high numerical aperture of objective lens. We show that the axial electric field is responsible for lateral components of the scattering and temporal forces, and hence, controls the scattering directions of the Rayleigh particles. These findings provide important information about the dynamic optical trapping of the Rayleigh particles by highly focused ultrashort laser pulses. (c) 2012 Elsevier B.V. All rights reserved.
Rapid and efficient purification of chrysophanol in Rheum Palmatum LINN by supercritical fluid extraction coupled with preparative liquid chromatography in tandem
(2012-04-15)
Lo, Tiffany Chien-Ting
;
Nian, Hung-Chi
;
Chiu, Kong-Hwa
;
Wang, Ai-Yih
;
Wu, Ben-Zen
Chrysophanol has high pharmaceutical values. However, it was difficult to use the traditional extraction method to extract high-concentration chrysophanol. Therefore, the purpose of this study is to purify and separate chrysophanol in traditional herb, Rheum Palmatum LINN, by using supercritical fluid extraction (SFE) and preparative high-performance liquid chromatography (P-HPLC) for rapid and large-scale isolation. The method is efficient for selective extraction of chrysophanol from the herbs, which have complex compositions. The extraction efficiency of chrysophanol with SFE is 25x higher than that of boiled water extraction under the same extraction time. The optimal conditions for SFE were 210 atm and 85 degrees C for 30 min; for P-HPLC, a C18 column was used with a gradient elution of methanol and 1% acetic acid at a flow rate of 10 mL/min. According to H-1 NMR and LC-MS analyses, the purity of the isolated chrysophanol was as high as 99%. The recovery for chrysophanol in Rheum after SPE/PHPLC processing was in the range of 88-91.5%. Compared with other extraction and purification methods, the sequential system (SFE/PHPLC) achieved the highest amount of extracted chrysophanol from Rheum Palmatum LINN (0.38 mg/g) and the shortest run time (3 h). Hence, this rapid and environmentally friendly method can separate compounds based on polarity with high efficiencies and, coupled with P-HPLC, it may be applicable in the large-scale production of foods and medicines in the future. (C) 2012 Elsevier B.V. All rights reserved.
Preface to the special issue in honor of Monique M. Martin
(2012-04-15)
Plaza, Pascal
;
Masuhara, Hiroshi
;
交大名義發表
;
National Chiao Tung University
Identifying transcriptional start sites of human microRNAs based on high-throughput sequencing data
(2012-04-15)
Tsou, Ann-Ping
;
Chien, Chia-Hung
;
Chiang-Hsieh, Pei-Yun
;
Tsai, Wei-Chih
;
Huang, Hsien-Da
具有氧化鐠之介電結構、具有氧化鐠之電晶體及其製造方法
(2012-04-16)
張翼
;
林岳欽
本發明係揭露一種具有氧化鐠之介電結構、具有氧化鐠之電晶體及其製造方法，該具有氧化鐠之電晶體係至少包含一三五族基板、一閘極介電層及一閘極。其中，閘極介電層係設於三五族基板上，閘極則設於閘極介電層上，而介電層係為氧化鐠（PrxOy）。本發明藉由使用具有高介電係數以及高能隙之氧化鐠（Pr6O11）作為介電層材料，除了有效的抑制漏電流外，更可進一步降低以三五族材料作為基板的元件之等效氧化物厚度（EOT）。
擴散光學斷層掃瞄之重疊／組合影像重建方法、裝置及程式產品
(2012-04-16)
蔡彰哲
;
方偉騏
一種擴散光學斷層掃瞄之重疊/組合影像重建方法，包含下述步驟：(a)建立至少一在預定範圍選擇多個待處理的子區域的處理模式；(b)對各子區域取得一部分光線強度矩陣；(c)對各子區域以前算模型取得一部分權重矩陣，並利用奇異分解法換算一部分權重逆矩陣；(d)將各子區域之部分光線強度矩陣與部分權重逆矩陣相乘得到各子區域之部分吸收係數矩陣；及(e)將各子區域之部分吸收係數矩陣依位置重疊/組合。