Browsing by Issue Date, starting with "2011-10-17"

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Infrared spectrum of mass-selected CH(3)S radicals investigated with infrared plus vacuum ultraviolet photoionization
(2011-10-17)
Han, Hui-Ling
;
Fu, Lung
;
Lee, Yuan-Pern
;
應用化學系
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應用化學系分子科學碩博班
We present a detailed spectral study of the atmospherically important methylthio (CH(3)S) radical demonstrating the advantage of IR-VUV photoionization for vibrational spectroscopy of free radicals due to its mass selectivity. Photolysis of CH(3)SH produced CH(3)S radicals that were ionized with (1 + 1) IR-VUV photoionization and detected with the time-of-flight technique. The IR spectrum of CH(3)S was obtained in the range 2790-3270 cm (1). Absorptions features near 2819 and 2904 cm (1) are assigned to nu(1) and nu(4) modes of CH(3)S, respectively, and those near 2978 and 3241 cm (1) are tentatively assigned as combination transitions 3(1)5(1)6(1)(e) and 3(1)5(1)6(1)(a), respectively, from the ground vibrational state. (C) 2011 Elsevier B.V. All rights reserved.
Temporal universal conductance fluctuations in RuO(2) nanowires due to mobile defects
(2011-10-17)
Lien, An-Shao
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Wang, L. Y.
;
Chu, C. S.
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Lin, Juhn-Jong
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電子物理學系
Temporal universal conductance fluctuations (TUCF's) are observed in RuO(2) nanowires at cryogenic temperatures. The fluctuations persist up to very high T similar to 10 K. Their root-mean-square magnitudes increase with decreasing T, reaching similar to 0.2e(2)/h at T less than or similar to 2 K. These fluctuations are shown to originate from scattering of conduction electrons with rich amounts of mobile defects in artificially synthesized metal oxide nanowires. TUCF characteristics in both one-dimensional saturated and unsaturated regimes are identified and explained in terms of current theories. Furthermore, the TUCF's as a probe for the characteristic time scales of the mobile defects (two-level systems) are discussed.
Temporal universal conductance fluctuations in RuO2 nanowires due to mobile defects
(2011-10-17)
Lien, An-Shao
;
Wang, L. Y.
;
Chu, C. S.
;
Lin, Juhn-Jong
;
電子物理學系
Temporal universal conductance fluctuations (TUCF's) are observed in RuO2 nanowires at cryogenic temperatures. The fluctuations persist up to very high T similar to 10 K. Their root-mean-square magnitudes increase with decreasing T, reaching similar to 0.2e(2)/h at T less than or similar to 2 K. These fluctuations are shown to originate from scattering of conduction electrons with rich amounts of mobile defects in artificially synthesized metal oxide nanowires. TUCF characteristics in both one-dimensional saturated and unsaturated regimes are identified and explained in terms of current theories. Furthermore, the TUCF's as a probe for the characteristic time scales of the mobile defects (two-level systems) are discussed.
Infrared spectrum of mass-selected CH3S radicals investigated with infrared plus vacuum ultraviolet photoionization
(2011-10-17)
Han, Hui-Ling
;
Fu, Lung
;
Lee, Yuan-Pern
;
應用化學系
;
應用化學系分子科學碩博班
We present a detailed spectral study of the atmospherically important methylthio (CH3S) radical demonstrating the advantage of IR-VUV photoionization for vibrational spectroscopy of free radicals due to its mass selectivity. Photolysis of CH3SH produced CH3S radicals that were ionized with (1 + 1) IR-VUV photoionization and detected with the time-of-flight technique. The IR spectrum of CH3S was obtained in the range 2790-3270 cm (1). Absorptions features near 2819 and 2904 cm (1) are assigned to nu(1) and nu(4) modes of CH3S, respectively, and those near 2978 and 3241 cm (1) are tentatively assigned as combination transitions 3(1)5(1)6(1)(e) and 3(1)5(1)6(1)(a), respectively, from the ground vibrational state. (C) 2011 Elsevier B.V. All rights reserved.
Microwave absorption in the cores of Abrikosov vortices pinned by artificial insulator inclusion
(2011-10-17)
Rosenstein, B.
;
Shapiro, I.
;
Deutch, E.
;
Shapiro, B. Ya.
;
電子物理學系
The spectrum of core excitations of the Abrikosov vortex pinned by a dielectric inclusion or nanoholes the size of the coherence length is considered using the Bogoliubov-deGennes equations beyond the semiclassical approximation. While the lowest excitation, minigap, in the unpinned (or pinned by a metallic defect) vortex is of the order of Delta(2)/E(F), it becomes of the order of the superconducting gap Delta (E(F) is Fermi energy). The reconstruction of the quasiparticle excitations' spectrum has a significant impact on optical properties and on the tunneling density of states. We calculate the absorption amplitude and point out that, while in scanning tunneling microscopy the energy gap Lambda(DOS) is between a quasiparticle state with angular momentum mu(e) = mu(0) > 1/2 and quasihole with mu(h) = -mu(0), the microwave absorption gap, Delta(dir), is between the states with mu(e) = mu(h) +/- 1. It is shown that Delta(dir) > Delta(DOS). The large minigap might play a role in magneto-transport phenomena broadly associated with the "superconductor-insulator" transition in quasi-two-dimensional systems in which small insulating inclusions are generally present.
《不連續的時代》：如何思考未來並洞察趨勢
(2011-10-19)
陳國華
;
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。
交大e-News第104期
(2011-10-20)
Secretariat
;
國立交通大學秘書室
VEHICLE TRACKING SYSTEM AND TRACKING METHOD THEREOF
(2011-10-20)
Wu Bing-Fei
;
Chen Yen-Lin
;
Huang Hao-Yu
;
Fan Chung-Jui
The present invention discloses a vehicle tracking system and method, and the tracking method comprises the steps of capturing a bright object from an image by the bright object segmentation; labeling the bright object by a connected component labeling method and forming a connected component object; identifying, analyzing and combining the characteristics of the connected component object to form a lamp object by the bright object recognition; tracking the trajectory of the lamp object by a multi-vehicle tracking method; and identifying the type of a vehicle having the lamp object by the vehicle detection/recognition and counting the number of various vehicles.
Self Assembled Liquid Crystal Polymers on Photo-Irradiated Alignment Surfaces for Tailoring Response Properties of Liquid Crystal Molecules
(2011-10-20)
Huang, Jung Y.
;
Li, Liu S.
;
光電工程學系
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Department of Photonics
A liquid crystal polymer (LCP) self-assembled on a photo-irradiated substrate can modify the viscoelastic response of liquid crystal medium on the substrate. Sum-frequency vibrational spectroscopy shows that the phenyl groups of LCP are oriented epitaxially with layer thickness and an in-plane alignment order much higher than that at the photo-irradiated surface can be yielded. The liquid crystal molecules confined between the LCP-coated substrates reveals a stronger correlation among the thermally excited fluctuation modes. Our finding can be used to tailor the boundary forces on alignment substrates and to optimize the device performance.
Physical properties of syndiotactic polystyrene (sPS)/poly(2,6-dimethyl-1,4-phenylene oxide (PPO) alloys and their feasible estimation for reflective cups of light emitting diodes (LEDs)
(2011-10-20)
Chung, Ming-Hua
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Lin, Jian-Shian
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Hsieh, Tsung-Eong
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Chen, Nien-Po
;
Chen, Chen-Ming
In this paper, the effects of antioxidants and processing parameters on the thermal stability and processability of sPS have been investigated. Experimental results indicate that a long processing duration and mechanic shearing force accelerate the thermal oxidation and addition of antioxidants into sPS can effectively improve color contamination and thermal stability. Furthermore, feasible estimation of sPS/PPO alloys for reflective cups of light emitting diodes (LEDs) have also been made, demonstrating that sPS/PPO alloys are potential candidates by the appropriate prescription of impact modifiers, flame retardants, and titanium dioxide. (C) 2011 Elsevier B.V. All rights reserved.
Relative Isomer Abundance of Fullerenes and Carbon Nanotubes Correlates with Kinetic Stability
(2011-10-20)
Fedorov, A. S.
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Fedorov, D. A.
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Kuzubov, A. A.
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Avramov, P. V.
;
Nishimura, Y.
A methodology to evaluate the kinetic stability of carbon nanostructures is presented based on the assumption of the independent and random nature of thermal vibrations. The kinetic stability is directly correlated to the cleavage probability for the weakest bond of a given nanostructure. The application of the presented method to fullerenes and carbon nanotubes yields clear correlation to their experimentally observed relative isomer abundances. The general and simple formulation of the method ensures its applicability to other nanostructures for which formation is controlled by kinetic factors.
Formation of Arrays of Free-Standing CdS Quantum Dots Using the Langmuir-Blodgett Technique
(2011-10-20)
Protasov, Dmitry Yu.
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Jian, Wen-Bin
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Svit, Kirill A.
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Duda, Tatyana A.
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Teys, Sergei A.
Aggregation clusters of CdS quantum dots (QDs) on the highly ordered pyrolytic graphite substrate were investigated by atomic force microscopy and scanning tunneling microscopy. QDs were initially formed within Y-type Langmuir-Blodgett (LB) films of cadmium behenate. The LB matrix was then removed by annealing. To study the process of QD assembly, the density of QDs in the initial film was varied systematically by increasing the number of monolayers (MLs) 0 from 1 to 20 ML. It was found that, at a small LB ML number, only a small part of CdS molecules form into QDs by diffusion along the plane of LB layers. With an increase of the LB ML number, the interlayer diffusion arises that leads to almost full binding of CdS molecules into QDs. The individually standing QDs were formed on the substrate for 1 and 2 ML samples. The QD size distributions of the samples with a small ML number are broader than that predicted by the two-dimensional Lifshitz-Slezov diffusion model. With an increase of the LB matrix thickness, QDs begin to assemble into clusters, revealing a ribbon structure due to diffusion-limited aggregation, and for the 20 ML LB matrix, a submonolayer QD film arises. By analyzing the occurrence of QDs as a function of aggregation number, pair bondings were estimated to be about 34 and 62 meV for the 4 and 8 ML samples, respectively.
Desymmetrization of 2,4,5,6-Tetra-O-benzyl-D-myo-inositol for the Synthesis of Mycothiol
(2011-10-21)
Chung, Chuan-Chung
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Zulueta, Medel Manuel L.
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Padiyar, Laxmansingh T.
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Hung, Shang-Cheng
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應用化學系
An efficient chemical synthesis of mycothiol Involving the regioselective ketopinyl desymmetrization of 2,4,5,6-tetrabenzylated D-myo-inositol as the key step Is described. Together with a highly alpha-stereoselective D-glucosaminylation, the whole procedure was accomplished in eight steps with an overall yield of 40%.
Compact dual-passband microstrip bandpass filters with larger design flexibility and multi-spurious suppression
(2011-10-21)
Chang, L-M.
;
Jiang, M.
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
Compact folded stepped impedance resonators (SIRs) with a novel asymmetric structure are used to design dual-passband filters with multi-spurious suppression. A complete design procedure enhancing both overall design flexibility and suppressing spurious responses is detailed. The new asymmetric SIR structure can effectively increase the degree of freedom (DOF) in the dual-passband bandwidth design. Extra DOF is simultaneously incorporated so that transmission zeros of the coupling stages may be adjusted to suppress unwanted spurious responses. Owing to circuit symmetry and a short coupling length, the circuit can be easily folded and the size is decreased by 62% compared with the previous work. The measured results agree well with the simulation and show that the attenuation level of the upper stopband is greater than 30 dB up to more than 20 GHz (8.16f(0)).
A specific and ratiometric chemosensor for Hg2+ based on triazole coupled ortho-methoxyphenylazocalix[4]arene
(2011-10-21)
Wang, Nae-Jen
;
Sun, Chung-Ming
;
Chung, Wen-Sheng
;
應用化學系
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Department of Applied Chemistry
Calix[4]arene 3, which contains two distal triazole groups on the lower rim and two distal o-methoxyphenylazo groups on the upper rim, was synthesized and found to be a specific and ratiometric sensor for Hg2+ in a polar protic solvent. A series of o-methoxyphenylazo derivatives (3, 4, 5, 7, and 9) were synthesized, which proved that the lower-rim triazoles and the hydroxyl azophenol(s) were the major ligands for metal ion binding. Though analogues 4 and 10 showed some sensitivity for Hg2+, compound 3 was the only ratiometric chemosensor for Hg2+ among the series of azocalix[4]arenes synthesized in this work. The formation of 3. Hg2+ complex was supported by UV/vis and NMR titration studies and Mass spectrometry. Based on the symmetrical features of NMR spectra of 3 center dot Hg2+, the complex is believed to be symmetrical with respect to the calix[4]arene cavity. Furthermore, the complex was determined to be 1:1 binding stoichiometry by Job's plot, and the association constant was determined to be 4.02 x 10(3) M-1 using Benesi-Hildebrand plot. (C) 2011 Elsevier Ltd. All rights reserved.
Thieno[3,2-b]pyrrolo Donor Fused with Benzothiadiazolo, Benzoselenadiazolo and Quinoxalino Acceptors: Synthesis, Characterization, and Molecular Properties
(2011-10-21)
Cheng, Yen-Ju
;
Chen, Chiu-Hsiang
;
Ho, Yu-Ju
;
Chang, Shu-Wei
;
Witek, Henryk A.
Nitrogen-bridged donor acceptor multifused dithienopyrrolobenzothladiazole (DTPBT) and dibenzothiadiazolopyrrolothlophene (DBTPT) were successfully synthesized by intramolecular Cadogan annulation. The electron-deficient benzothiadiazole unit In DTPBT can be converted to benzoselenadiazole and quinoxaline moieties through reduction/cyclization to generate dithienopyrrolobenzoselenadiazole (DTPBSe) and dithienopyrroloquinoxaline (DTPQX), respectively. The nitrogen atoms function as the bridges for covalent planarization to induce intermolecular interaction and intramolecular charge transfer.
A specific and ratiometric chemosensor for Hg(2+) based on triazole coupled ortho-methoxyphenylazocalix[4]arene
(2011-10-21)
Wang, Nae-Jen
;
Sun, Chung-Ming
;
Chung, Wen-Sheng
;
應用化學系
;
Department of Applied Chemistry
Calix[4]arene 3, which contains two distal triazole groups on the lower rim and two distal o-methoxyphenylazo groups on the upper rim, was synthesized and found to be a specific and ratiometric sensor for Hg(2+) in a polar protic solvent. A series of o-methoxyphenylazo derivatives (3, 4, 5, 7, and 9) were synthesized, which proved that the lower-rim triazoles and the hydroxyl azophenol(s) were the major ligands for metal ion binding. Though analogues 4 and 10 showed some sensitivity for Hg(2+), compound 3 was the only ratiometric chemosensor for Hg(2+) among the series of azocalix[4]arenes synthesized in this work. The formation of 3. Hg(2+) complex was supported by UV/vis and NMR titration studies and Mass spectrometry. Based on the symmetrical features of NMR spectra of 3 center dot Hg(2+), the complex is believed to be symmetrical with respect to the calix[4]arene cavity. Furthermore, the complex was determined to be 1:1 binding stoichiometry by Job's plot, and the association constant was determined to be 4.02 x 10(3) M(-1) using Benesi-Hildebrand plot. (C) 2011 Elsevier Ltd. All rights reserved.
Computational analysis of a novel mutation in ETFDH gene highlights its long-range effects on the FAD-binding motif
(2011-10-21)
Er, Tze-Kiong
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Chen, Chih-Chieh
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Liu, Yen-Yi
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Chang, Hui-Chiu
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Chien, Yin-Hsiu
Background: Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is an autosomal recessive disease caused by the defects in the mitochondrial electron transfer system and the metabolism of fatty acids. Recently, mutations in electron transfer flavoprotein dehydrogenase (ETFDH) gene, encoding electron transfer flavoprotein: ubiquinone oxidoreductase (ETF:QO) have been reported to be the major causes of riboflavin-responsive MADD. To date, no studies have been performed to explore the functional impact of these mutations or their mechanism of disrupting enzyme activity. Results: High resolution melting (HRM) analysis and sequencing of the entire ETFDH gene revealed a novel mutation (p.Phe128Ser) and the hotspot mutation (p.Ala84Thr) from a patient with MADD. According to the predicted 3D structure of ETF: QO, the two mutations are located within the flavin adenine dinucleotide (FAD) binding domain; however, the two residues do not have direct interactions with the FAD ligand. Using molecular dynamics (MD) simulations and normal mode analysis (NMA), we found that the p. Ala84Thr and p.Phe128Ser mutations are most likely to alter the protein structure near the FAD binding site as well as disrupt the stability of the FAD binding required for the activation of ETF: QO. Intriguingly, NMA revealed that several reported disease-causing mutations in the ETF: QO protein show highly correlated motions with the FAD-binding site. Conclusions: Based on the present findings, we conclude that the changes made to the amino acids in ETF: QO are likely to influence the FAD-binding stability.
靜電放電防護裝置以及積體電路
(2011-10-21)
柯明道
;
顏承正
;
陳東暘
一種積體電路，包括一核心電路以及一靜電放電防護裝置。核心電路耦接於一第一電源線及一第二電源線之間。靜電放電防護裝置包括，一放電元件、一第一偵測電路以及一第二偵測電路。當放電元件被致能時，則在一第一及第二電源線之間提供一放電路徑，當放電元件被禁能時，則停止提供放電路徑。第一偵測電路耦接於第一及第二電源線之間。當第一電源線發生一靜電放電事件時，則第一偵測電路致能放電元件。當第一電源線未發生靜電放電事件時，則第二偵測電路禁能放電元件。
時光的採集者　叮咚
(2011-10-23)
陳燕珩
;
Department of Communication and Technology
;
傳播與科技學系
在數位相機盛行、許多人爭相學習攝影技術的現在，叮咚（李建廷）選擇用底片相機紀錄生活中的片刻。攝影之路十年走來，不刻意專研艱深的攝影理論，也沒有專業複雜的攝影器材輔助，他憑著對底片膠卷的熱愛，與按下快門的勇氣，用照片傳達出簡單而深刻的生活態度。