Browsing by Issue Date, starting with "2003-12-12"

Now showing 1 - 20 of 72106

A novel cold-adapted imidase from fish Oreochromis niloticus that catalyzes hydrolysis of maleimide
(2003-12-12)
Huang, CY
;
Yang, YS
;
生醫工程研究所
;
Institute of Biomedical Engineering
In this paper we report the first comparative study of cold-adapted imidase (EC 3.5.2.2) from the fish (Oreochromis niloticus) liver and its thermophilic counterparts taken from pig liver and Escherichia coli (overexpressed recombinant hydantoinase from Agrobacterium radiobacter NRRL B1). Approximately 6000-fold purification and a 40% yield of fish imidase activity were obtained through ammonium sulfate precipitation, octyl, chelating, DEAE, and hydroxyapatite chromatography. This cold-adapted imidase was characterized by a specific activity 10- to a 100-fold higher than those of its thermophilic counterparts below room temperature (25 degreesC or lower) conditions but less stable at elevated temperatures (40 degreesC or higher). A less organized helical structure (compared to those of pig liver and bacterial imidases) was observed by circular dichroism. Furthermore, maleimide was first identified as a novel substrate of all imidases examined, and confirmed by HPLC and NMR analysis. These results constituted a first study to discover a novel cold-adapted imidase with surprising high activity. These findings might be also helpful for industrial application of imidase. (C) 2003 Elsevier Inc. All rights reserved.
祭大荒
(2003-12-15)
管管
Effect of low-temperature annealing on the luminescent lifetime and negative differential resistance of silicon-implanted borosilicate glass
(2003-12-15)
Lin, GR
;
光電工程學系
;
Department of Photonics
The silicon-implanted borosilicate glass (BSO:Si+) low-temperature (500 degreesC) annealed at a different time are structurally, electrically, and optically characterized. The weak and broadened x-ray diffraction reveal insignificant Si nano-crystallization even after long-term annealing, whereas the redshifted photoluminescence (PL) interprets the change in category and the decrease in density of irradiative defects in BSO:Si+. Time-resolved PL analysis reveals a lengthening luminescent lifetime of BSO:Si+ from 1.7 to 2.8 ns, which indicates that the density ratio of nonradiative defects in as-implanted BSO:Si+ are reduced by one-tenth after annealing for 60 min. Transmission line mode analysis shows that both the leakage current and the contact resistance of a metal-BSO:Si+-metal diode has dramatically changed by three orders of magnitude. A strong negative differential resistance (NDR) and associated double-barrier electron tunneling phenomenon are observed with a threshold electric field of 290-350 kV/cm. The decreasing barrier height of the metal-BSO:Si+ junction from 3.0 to 1.9 eV is mainly contributed by deep-level defects with activation energy of similar to1 eV. After annealing, the NDR effect significantly diminishes, the barrier height raises to >2.4 eV, and most electrical characteristics of the metal-BSO:Si+ junction have recovered back to be comparable with those of the metal-BSO junction due to the elimination of these defects. (C) 2003 American Institute of Physics.
祭大荒
(2003-12-15)
管管
祭大荒
(2003-12-15)
管管
祭大荒
(2003-12-15)
管管
Electron field emission from fluorinated amorphous carbon nanoparticles on porous alumina
(2003-12-15)
Lai, SH
;
Huang, KP
;
Pan, YM
;
Chen, YL
;
Chan, LH
The fluorinated amorphous carbon nanoparticles (a-C:F NPs) films have been prepared on a porous alumina at a lower temperature of similar to100 degreesC by an ECR-CVD system with a mixture of CF4, C2H2 and Ar as precursors. The morphology of a-C:F NPs films was verified by FESEM. The microstructure and chemical bonding nature of the a-C:F NPs films were investigated by Raman spectroscopy and XPS, respectively. The fluorinated samples need a lower field (similar to2.25 V/mum for 10.6% F a-C:F NPs films) to emit the electron than unfluorinated ones. The excellent field-emission properties of a-C:F NPs films are due to the effect of the shape, fluorine doping and dangling bonds. (C) 2003 Elsevier B.V. All rights reserved.
Electrical and dielectric properties of low-temperature crystallized Sr0.8Bi2.6Ta2O9+x thin films on Ir/SiO2/Si substrates
(2003-12-20)
Chou, HY
;
Chen, TM
;
Tseng, TY
;
應用化學系
;
電子工程學系及電子研究所
Ferroelectric thin films of bismuth layer structured compounds, Sr0.8Bi2.6Ta2O9+x (SBT) were deposited onto Ir/SiO2/Si substrates using metal organic decomposition (MOD) method. The crystallization of the SBT thin films annealed at various temperatures was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The polarization (P) versus electric field (E) characteristics exhibited a systematic variation from linear to non-linear polarization (hysteresis) with an increase in the annealing temperature of the SBT films. The leakage current density and dielectric constant of the SBT films were also strongly dependent on the annealing temperature, which in turn determined the grain size, mean surface roughness and inter diffusion through interfacial layers. The lowest leakage current density of 10(-9) A cm(-2) at 100 kV cm(-1) was obtained for SBT thin film annealed at 450 degreesC. The SBT thin films annealed at 650 and 700 degreesC remained fatigue-free up to 10 switching cycles. (C) 2003 Elsevier B.V. All rights reserved.
A novel low-temperature growth and characterization of single crystal ZnO nanorods
(2003-12-20)
Hung, CH
;
Whang, WT
;
材料科學與工程學系
;
Department of Materials Science and Engineering
One-dimensional (1D) single crystal ZnO nanorods directly grown on ZnO nanostructured substrates by soft chemical method is proposed. Employing a novel two steps procedure, the ZnO nanorods with a diameter about 45 nm can be successfully grown on substrate in aqueous solution at attractive low temperature in 90 degreesC, permitting large-scale fabrication with a relatively low cost and a potential application in optoelectronic nanodevices. The structures, appearances and optical properties of ZnO nanorods also have been characterized. (C) 2003 Elsevier B.V. All rights reserved.
Doped red organic electroluminescent devices based on a cohost emitter system
(2003-12-22)
Liu, TH
;
Iou, CY
;
Chen, CH
;
應用化學系
;
光電工程學系
We have developed an efficient red emitter in organic light-emitting diodes based on the fluorescent dye 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetra-methyljulolidyl-9-enyl)-4H-pyran doped in a cohost emitter system of 5,6,11,12-tetraphenylnathacene/tris(8-hydroxyquinolinato)aluminum which achieved an electroluminescence (EL) efficiency of 4.4 cd/A and 2.1 lm/W at 20 mA/cm(2) and 6.8 V, with a near saturated Commission Internationale d'Eclairage coordinates (x=0.65, y=0.35). This cohost emitter system has the advantage of alleviating the current-induced fluorescence quenching often encountered in red organic EL devices and greatly improves the EL efficiency over a wide range of drive current conditions. From accelerated degradation tests, a device half-life of about 33 800 h can be projected in this system at an initial device luminance of 100 cd/m(2). (C) 2003 American Institute of Physics.
Traceability on RSA-based partially signature with low computation
(2003-12-25)
Hwang, MS
;
Lee, CC
;
Lai, YC
;
資訊工程學系
;
Department of Computer Science
In this article, we show that the Chien et al.'s partially blind signature scheme based on RSA public cryptosystem could not meet the untraceability property of a blind signature. (C) 2002 Elsevier Inc. All rights reserved.
Partial wave analysis of scattering with nonlocal Aharonov-Bohm effect
(2003-12-29)
Lin, DH
;
應用數學系
;
Department of Applied Mathematics
Partial wave theory of a two-dimensional scattering problem for an arbitrary short range potential and a nonlocal Aharonov-Bohm magnetic flux is established. The scattering process of a "hard disk" like potential and the magnetic flux is examined. Since the nonlocal influence of magnetic flux on the charged particles is universal, the nonlocal effect in hard disk case is expected to appear in quite general potential system and will be useful in understanding some phenomena in mesoscopic physics. (C) 2003 Elsevier B.V. All rights reserved.
製備合成氧化物在互補式金氧半閘極介電層及自旋電元件應用之研究(III)
(2004)
趙天生
;
TIEN-SHENGCHAO
;
交通大學電子物理系
高等教育的國際化：台灣、日本及荷蘭外國學生政策之比較研究 (I)
(2004)
戴曉霞
;
TAI HSIOU-HSIA
;
國立交通大學教育研究所
高等教育的國際化主要可以分由學生、教師、課程及研究四個方向來進行。由於國際學生的流動人數龐大，其消費構成價值數百億美元的市場，因此招收外國學生不只有利於長期政治、經貿關係的耕耘、國家競爭力的提升，更是重要的外銷產品，故工業先進國家和區域性組織將之視為既是高等教育、也是政治和經濟的重要策略。這種情況在「世界貿易組織」及其前身「關稅暨貿易總協定」將教育、保險、金融、運輸等十四項服務業納入國際貿易的項目，並在1994 年完成《服務業貿易總協定》（簡稱GATS）之後更為顯著。根據GATS 的規定，會員國必須依其承諾開放教育市場，並給予其他會員國最惠國待遇。此一國際協議除了強化了教育的產業和商品特質，更引發新一波國際教育市場的競爭。工業先進（特別是英語系）國家固然想進一步提升其在此一市場佔有率，工業新興國家也嚴陣以待，以提升高等教育的競爭力及各種吸引外國學生的策略，企圖扮演更積極、更主動的角色，以便在國際高等教育市場體系中能由邊陲位置移往核心位置，這也是我國教育部在2003 年8 月26 日所提出的「宏觀高等教育方案」中，計畫未來五年積極擴大招收外國學生的主要原因。由於日本、荷蘭和我國皆屬於非英語系國家，在國際化和招收外國學生方面有相似的困難。此外，前者和我國有地緣關係，後者在國家規模及發展階段與我國相近，且兩國早在十餘年前即已推動相關政策，其經驗可提供我國「他山之石」的寶貴借鏡。因此本研究擬以日本、荷蘭和我國為研究對象，運用文獻/文件分析法、訪談法和比較法，分兩年深入瞭解上述三國高等教育國際化及外國學生政策的目標、政策內容與相關辦法、實施方式與過程、所遭遇的困難和對策等，其次找出日本、荷蘭和我國在相關政策上的比較點，最後分析日本和荷蘭經驗對於我國高等教育國際化及外國學生政策的參考和應用價值，並提出針對我國政策的具體建議。
A novel distributed charge storage element fabricated by the oxidation of amorphous silicon carbide
(2004)
Chang, TC
;
Yan, ST
;
Chen, YT
;
Liu, PT
;
Sze, SM
A novel distributed charge storage element fabricated by the oxidation of amorphous silicon carbide is proposed. For low-temperature oxidation processes, the oxidized SiCO gate stack shows a larger memory window due to the retainable dangling bonds with more Si-C bonding types and less Si-O bonds. Under 5 V write operation of the low-temperature oxidized SiCO stack, a 1.5 V threshold voltage shift is exhibited, which is sufficient for a memory device to define "0'' and "1.'' Also, the low-temperature oxidation process of the SiCO layer saves the thermal budget for the manufacturing processes of nonvolatile memory devices. (C) 2004 The Electrochemical Society.
動態系統最佳設計數值方法及應用(I)
(2004)
曾錦煥
;
交通大學機械工程研究所
長久以來，動態系統所引發的非線性行為特性一直困擾著工程設計人員，而只考慮靜態模式下採用傳統最佳化設計方法所求得的設計往往在實際工作環境的應用上有所困難。因此，如何整合動態分析與最佳化設計方法，以求得符合實際動態需求的最佳設計便成為目前研究人員所亟欲解決的重點。本研究計畫將依據最佳化理論基礎，融合動態分析與數值分析求解技巧，發展一套通用之動態系統最佳設計方法與軟體。在研究過程中，非線性動態系統之分析與求解亦將納入考量以符合實際工程問題之需求。另外，針對工程設計中經常存在的離散（整數）最佳化設計問題，本研究將依據混合整數非線性規劃法(MINLP)做進一步的研究，以期將此類型問題之求解，納入本研究計畫所發展軟體之另一重點功能。本研究計畫所發展之方法與軟體將應用於實際工程設計案例，並藉此進行方法之驗證。
The World Cup 2002: a view from the streets
(Routledge, 2004)
A. Yamamoto
鋼構造抗彎接頭耐震行為(I)
(2004)
陳誠直
;
CHEN CHENG-CHIH
;
交通大學土木工程系
1994 年美國北嶺與1995 年日本阪神地區發生強烈地震，許多抗彎鋼構造建築物的梁柱接頭遭受嚴重的損傷並顯現出脆性的撕裂破壞。樑柱接頭的破壞將導致整體抗彎構架強度及韌性能力的無法發揮。因此，震後國內外專家學者進行甚多的研究以改善鋼骨梁柱接頭的耐震能力與韌性。然而研究之試體柱多數為H 型柱，僅有少數的研究探討鋼骨箱型柱樑柱接頭的行為，而箱型柱為國內常用之柱斷面。為瞭解與改良箱型柱樑柱接頭的行為，本研究提出將靠近柱面之梁翼板擴大，以使塑鉸產生在遠離柱面之梁斷面上並降低樑柱接面處之需求。本研究擬利用非線性有限元素分析，對鋼骨箱型柱樑柱接頭進行擴翼式接頭改良研究，針對不同參數研究，探討箱型柱樑柱接頭之力學行為，如非彈性行為、塑鉸之形成、韌性之增強。並依據有限元素分析結果以實尺寸試體進行樑柱接頭反覆載重試驗，以驗證接頭之耐震行為，期望發展耐震能力更可靠、韌性行為更優良之箱型柱接頭型式以及設計流程。
尖端光譜學技術在雷射光化學的應用(III)
(2004)
李遠鵬
;
LEE YUAN-PERN
;
交通大學應用化學系
用於寬頻通信之高性能單一載具整合晶片系統-子計畫三：用於寬頻網路之微波頻率合成電路技術(II)
(2004)
陳巍仁
;
WEI-ZENCHEN
;
交通大學電子工程系