Browsing by Issue Date, starting with "2013-07-19"

Now showing 1 - 20 of 31145

Rapid and highly sensitive detection of Enterovirus 71 by using nanogold-enhanced electrochemical impedance spectroscopy
(2013-07-19)
Li, Hsing-Yuan
;
Tseng, Shing-Hua
;
Cheng, Tsai-Mu
;
Chu, Hsueh-Liang
;
Lu, Yu-Ning
Enterovirus 71 (EV71) infection is an emerging infectious disease causing neurological complications and/or death within two to three days after the development of fever and rash. A low viral titre in clinical specimens makes the detection of EV71 difficult. Conventional approaches for detecting EV71 are time consuming, poorly sensitive, or complicated, and cannot be used effectively for clinical diagnosis. Furthermore, EV71 and Coxsackie virus A16 (CA16) may cross react in conventional assays. Therefore, a rapid, highly sensitive, specific, and user-friendly test is needed. We developed an EV71-specific nanogold-modified working electrode for electrochemical impedance spectroscopy in the detection of EV71. Our results show that EV71 can be distinguished from CA16, Herpes simplex virus, and lysozyme, with the modified nanogold electrode being able to detect EV71 in concentrations as low as 1 copy number/50 mu 1 reaction volume, and the duration between sample preparation and detection being 11 min. This detection platform may have the potential for use in point-of-care diagnostics.
Low density supercritical fluids precipitation of 9-cis and all trans-beta-carotenes enriched particulates from Dunaliella salina
(2013-07-19)
Chen, Jian-Ren
;
Wu, Jia-Jiuan
;
Lin, Justin Chun-Te
;
Wang, Yuan-Chuen
;
Young, Chiu-Chung
In this study, supercritical anti-solvent (SAS) pulverization coupled with reverse phase elution chromatography was employed to isolate 9-cis and trans-beta-carotenes from Dunaliella saline. Total concentration of 9-cis (134.7 mg/g) and trans-beta-carotene (204.2 mg/g) was increased from 338.9 mg/g of the ultrasonic extract to 859.7 mg/g (338.9 for 9-cis and 520.8 for trans) of the elution fraction. The SAS pulverization of the collected fraction further produced submicron-sized particulates containing 932.1 mg/g (355.6 for 9-cis and 576.5 for trans) of total beta-carotenes with a recovery of 86.3% (83.9% for cis and 87.8% for trans). Effects of two SAS operational conditions on the purity, recovery of total beta-carotenes, mean size and morphology of the precipitates were obtained from an experimentally designed method. Generation of micronized particulates enriched with 9-cis and trans-beta-carotenes by low-density SAS was proved to be feasible and environmental benign. (C) 2013 Elsevier B.V. All rights reserved.
Poly(2,3-diphenyl-1,4-phenylenevinylene) (DP-PPV) derivatives: Synthesis, properties, and their applications in polymer light-emitting diodes
(2013-07-19)
Chen, Jiun-Tai
;
Hsu, Chain-Shu
;
應用化學系
;
Department of Applied Chemistry
Poly(1,4-phenylene vinylene) (PPV) has drawn a great deal of attention in the last two decades because of their applications in areas such as light-emitting diodes. To improve the solubility and optoelectronic properties, various PPV derivatives have been synthesized and investigated for their light-emitting performance. Among PPV derivatives, poly(2,3-diphenyl-1,4-phenylenevinylene) (DP-PPV) and its derivatives have been widely studied because of their promising electronic properties. Here, we review the synthesis, properties, and device performances of DP-PPV derivatives, which exhibit high external efficiency and brightness in polymer light-emitting diodes. For example, long alkyl chains were introduced to increase the solubility of DP-PPV. DP-PPV derivatives having liquid crystalline side groups were also synthesized and polarized emissions were obtained. In addition, bulky dendritic side groups were incorporated on the pendant phenyl ring and quantum efficiency of the device was significantly enhanced with increasing the generation of dendrons. By introducing methoxy or long branched alkoxy chains into DP-PPV, a maximum brightness of 78050 cd/m(2) with a low turn-on voltage of 4.0 V was also achieved by fabricating a multilayer electroluminescent device. In addition, the self-assembly behaviors and optical properties of different DP-PPV derivatives in solution and in confined environment are also discussed. (C) 2013 Elsevier Ltd. All rights reserved.
Low density supercritical fluids precipitation of 9-cis and all trans-beta-carotenes enriched particulates from Dunaliella salina
(2013-07-19)
Chen, Jian-Ren
;
Wu, Jia-Jiuan
;
Lin, Justin Chun-Te
;
Wang, Yuan-Chuen
;
Young, Chiu-Chung
In this study, supercritical anti-solvent (SAS) pulverization coupled with reverse phase elution chromatography was employed to isolate 9-cis and trans-beta-carotenes from Dunaliella saline. Total concentration of 9-cis (134.7 mg/g) and trans-beta-carotene (204.2 mg/g) was increased from 338.9 mg/g of the ultrasonic extract to 859.7 mg/g (338.9 for 9-cis and 520.8 for trans) of the elution fraction. The SAS pulverization of the collected fraction further produced submicron-sized particulates containing 932.1 mg/g (355.6 for 9-cis and 576.5 for trans) of total beta-carotenes with a recovery of 86.3% (83.9% for cis and 87.8% for trans). Effects of two SAS operational conditions on the purity, recovery of total beta-carotenes, mean size and morphology of the precipitates were obtained from an experimentally designed method. Generation of micronized particulates enriched with 9-cis and trans-beta-carotenes by low-density SAS was proved to be feasible and environmental benign. (C) 2013 Elsevier B.V. All rights reserved.
Simple and direct measurements of pretilt angles in hybrid-aligned nematic liquid-crystal cells
(2013-07-20)
Wang, Sheng-Ya
;
Wu, Huang-Ming
;
Yang, Kei-Hsiung
;
光電系統研究所
;
影像與生醫光電研究所
We have developed a general approach to perform direct measurements of the pretilt angles from 0 degrees to 75 degrees in hybrid-aligned nematic (HAN) liquid-crystal cells whose cell gaps can also be accurately determined with the help of known pretilt angles. In this paper, we have used a Zeeman laser system to measure the angular-dependence phase retardation of the HAN cells and MATLAB mathematical software to carry out theoretical calculations and fit the measured data to derive the pretilt angles. In general, pretilt angles adjacent to opposite substrates of a HAN cell are different. Our measured pretilt angles of the HAN cell were in good agreement with the measured pretilt angles of two accompanying homogenous cells whose alignment methods were the same as applied to opposite substrates of the HAN cell, respectively. The advantage of direct measurement is easily applicable to measure the pretilt angles of aged HAN cells. (C) 2013 Optical Society of America
Optical imaging with spectrum aberration correction using a filtering macrolens
(2013-07-20)
Lin, Yu-Hsuan
;
Lai, Jyun-Yi
;
Tsai, Hsin-Yi
;
Chang, Han-Chao
;
Huang, Hung Ji
A filtering macrolens was developed to simultaneously achieve macro-optical imaging and correct spectrum aberration. The macrolens was a doublet lens comprising a filtering lens and a close-up lens. The shape of the filtering lens was designed to eliminate the optical path differences between the light rays in the absorbing medium. The close-up lens was designed to decrease the effective focal length of an ordinary camera lens to provide high magnification capability and collimate the diverging beams through the filtering lens. Experimental results demonstrated that the spectrum uniformity of the macro-optical images was markedly improved by the filtering macrolens. This innovation may be used in finite conjugate optical systems. (C) 2013 Optical Society of America
背景調適性二進制算術解碼裝置及其解碼方法
(2013-07-21)
廖元歆
;
張添烜
提供一種背景調適性二進制算術解碼裝置及其解碼方法，其中該裝置包含：背景記憶體位址計算器，用以計算下個周期所需之背景模型在背景模型記憶體中之儲存位址；混合式背景記憶體，用以讀取並儲存該背景記憶體位址計算器之背景模型；雙符號背景調適性二進制算術解碼器，用以依照該混合式背景記憶體之背景模型輸出若干個用以更新該背景模型之範圍與偏移量之參數，並決定若干符號(bins)，以及二進制語法元素比較器，用以依照該等符號判斷目前二進制序列是否符合語法元素之數值，用以選出正確的記憶體位址。
線接面式乾電極
(2013-07-21)
翟芸
;
林進燈
一種線接面式乾電極，其包括一導電安裝部以及其延伸有至少一導電接觸部，導電接觸部具有複數個間隔排列的彈性導電梳支，據以形成梳狀電極，用以撥開一受測者之毛髮並接觸皮膚。
Refined holographic entanglement entropy for the AdS solitons and AdS black holes
(2013-07-21)
Ishihara, Masafumi
;
Lin, Feng-Li
;
Ning, Bo
;
電子物理學系
;
Department of Electrophysics
We consider the refinement of the holographic entanglement entropy for the holographic dual theories to the AdS solitons and AdS black holes, including the corrected ones by the Gauss-Bonnet term. The refinement is obtained by extracting the UV-independent piece of the holographic entanglement entropy, the so-called renormalized entanglement entropy which is independent of the choices of UV cutoff. Our main results are: (i) the renormalized entanglement entropies of the AdS(d+1) soliton for d = 4, 5 are neither monotonically decreasing along the RG flow nor positive-definite, especially around the deconfinement/confinement phase transition; (ii) there is no topological entanglement entropy for AdS(5) soliton even with Gauss-Bonnet correction; (iii) for the AdS black holes, the renormalized entanglement entropy obeys an expected volume law at IR regime, and the transition between UV and IR regimes is a smooth crossover even with Gauss-Bonnet correction; (iv) based on AdS/MERA conjecture, we postulate that the IR fixed-point state for the non-extremal AdS soliton is a trivial product state. (C) 2013 Elsevier B.V. All rights reserved.
有機發光材料
(2013-07-21)
孟心飛
;
洪勝富
;
曾信榮
;
游佳達
;
葉重麟
提供一種具有下式(I)之化合物：其中，各取代基之定義係如說明書所界定。該化合物可與其他有機發光材料合併用於有機發光元件發光層。
顯示裝置之畫素補償電路
(2013-07-21)
劉柏村
;
竹立煒
本發明係有關於一種顯示裝置之畫素補償電路，其由一第一開關耦接一電壓，並受控於一第一掃描訊號；一儲存電容具有一第一端與一第二端，第一端耦接第一開關，第二端耦接於第二開關，一第二開關受控於第一掃描訊號，一驅動元件耦接於一資料線、儲存電容與第二開關，驅動元件用以產生一驅動電流，並傳送驅動電流至一發光元件。如此，本發明藉由控制第一開關與第二開關而產生與臨界電壓無關之驅動電流，使得畫素之亮度與臨界電壓無關，進而增加驅動電流的均勻性使面板可長時間操作，並減少亮度不均勻的特性。
電流式雙斜率溫度數位轉換裝置
(2013-07-21)
林明澤
;
洪崇智
本發明係揭露一種電流式雙斜率溫度數位轉換裝置，包含一溫度相依電流源與一參考電流源，首先，溫度相依電流源對一電容充電，接著參考電流源對電容進行放電，電容係連接至少一觸發器，觸發器根據電容之端電壓輸出一第一數位訊號至一邏輯控制器中，邏輯控制器再根據第一數位訊號，輸出一第二數位訊號至一時間至數位轉換器中，轉換器在參考電流對電容放電時，且第一數位訊號變動前，接收第二數位訊號與一時脈訊號，以產生對應之數位輸出值。本發明利用雙斜率架構達成高線性解析度的要求，以避免一般時域電路所產生的曲率效應。
Fabrication, characterization and simulation of Omega-gate twin poly-Si FinFET nonvolatile memory
(2013-07-22)
Yeh, Mu-Shih
;
Wu, Yung-Chun
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Hung, Min-Feng
;
Liu, Kuan-Cheng
;
Jhan, Yi-Ruei
This study proposed the twin poly-Si fin field-effect transistor (FinFET) nonvolatile memory with a structure that is composed of Omega-gate nanowires (NWs). Experimental results show that the NW device has superior memory characteristics because its Omega-gate structure provides a large memory window and high program/erase efficiency. With respect to endurance and retention, the memory window can be maintained at 3.5 V after 10(4) program and erase cycles, and after 10 years, the charge is 47.7% of its initial value. This investigation explores its feasibility in the future active matrix liquid crystal display system-on-panel and three-dimensional stacked flash memory applications.
The investigation of donor-acceptor compatibility in bulk-heterojunction polymer systems
(2013-07-22)
Huang, Jen-Hsien
;
Hsiao, Yu-Sheng
;
Richard, Eric
;
Chen, Chun-Chao
;
Chen, Peilin
The fullerene derivative, indene-C-60 bisadduct (ICBA), has been introduced into poly(3-hexylthiophene) (P3HT) to improve the efficiency of P3HT-based devices. However, we found that ICBA is not suitable for most low bandgap polymers. In this study, we have correlated the cell performance with surface energy between the donor and acceptor materials in a bulk-heterojunction cell. These results show that higher photocurrent can be attributed to the morphology improvement induced by larger surface energy difference (Delta gamma) between the low bandgap polymer and fullerene. These results also suggest that synthetic strategies which adjust the Delta gamma between donor and acceptor should be considered. (C) 2013 AIP Publishing LLC.
交大e-News第145期
(2013-07-22)
Secretariat
;
國立交通大學秘書室
High-Performance Flexible Waveguiding Photovoltaics
(2013-07-22)
Chou, Chun-Hsien
;
Chuang, Jui-Kang
;
Chen, Fang-Chung
;
光電學院
;
光電工程學系
The use of flat-plane solar concentrators is an effective approach toward collecting sunlight economically and without sun trackers. The optical concentrators are, however, usually made of rigid glass or plastics having limited flexibility, potentially restricting their applicability. In this communication, we describe flexible waveguiding photovoltaics (FWPVs) that exhibit high optical efficiencies and great mechanical flexibility. We constructed these FWPVs by integrating poly-Si solar cells, a soft polydimethylsiloxane (PDMS) waveguide, and a TiO2-doped backside reflector. Optical microstructures that increase the light harvesting ability of the FWPVs can be fabricated readily, through soft lithography, on the top surface of the PDMS waveguide. Our optimized structure displayed an optical efficiency of greater than 42% and a certified power conversion efficiency (PCE) of 5.57%, with a projected PCE as high as approximately 18%. This approach might open new avenues for the harvesting of solar energy at low cost with efficient, mechanically flexible photovoltaics.
Enhancement of the stability of resistive switching characteristics by conduction path reconstruction
(2013-07-22)
Huang, Jheng-Jie
;
Chang, Ting-Chang
;
Yu, Chih-Cheng
;
Huang, Hui-Chun
;
Chen, Yu-Ting
In this study, a Pt/BiFeO3/TiN device was fabricated and the resistance switching characteristics were investigated. After the first forming process, the conduction path was formed and exhibited unstable bipolar switching characteristics. Subsequently, the original conduction path was destroyed thoroughly by high negative bias. By reconstructing the conduction path after a second forming process (re-forming process), the device exhibits stable bipolar switching characteristics. Transmission electron microscopy analysis indicates that the stability of switching behavior was enhanced because of the joule heating effect, and is an easy way to improve the resistance switching characteristics. (C) 2013 AIP Publishing LLC.
Lambda(b) -> pl(-)(v)over-bar(l) form factors from lattice QCD with static b quarks
(2013-07-23)
Detmold, William
;
Lin, C-J. David
;
Meinel, Stefan
;
Wingate, Matthew
;
物理研究所
We present a lattice QCD calculation of form factors for the decay Lambda(b) -> p mu(-)(v) over bar (mu), which is a promising channel for determining the Cabibbo- Kobayashi-Maskawa matrix element vertical bar V-ub vertical bar at the Large Hadron Collider. In this initial study we work in the limit of static b quarks, where the number of independent form factors reduces to two. We use dynamical domain-wall fermions for the light quarks, and perform the calculation at two different lattice spacings and at multiple values of the light-quark masses in a single large volume. Using our form factor results, we calculate the Lambda(b) -> p mu-(v) over bar (mu) differential decay rate in the range 14 GeV2 <= q(2) <= q(max)(2), and obtain the integral integral(q2max)(14 GeV2) [d Gamma/dq(2)]dq(2)/vertical bar V-ub vertical bar(2) = 15.3 +/- 4.2 ps(-1). Combined with future experimental data, this will give a novel determination of vertical bar V-ub vertical bar with about 15% theoretical uncertainty. The uncertainty is dominated by the use of the static approximation for the b quark, and can be reduced further by performing the lattice calculation with a more sophisticated heavy-quark action.
N-bit digital-to-analog converting device
(2013-07-23)
Tseng Wei-Hsin
;
Wu Jieh-Tsorng
An N-bit digital-to-analog converting device includes: a decoder for converting an N-bit binary digital signal into a multi-bit thermometer code during each cycle of a clock signal alternating between first and second states, N being an integer not less than two; a random number generator for generating a reset signal having at least one high logic level bit and at least one low logic level bit that are equal in number and that have a random, time-varying arrangement; and a converting module coupled electrically to the decoder and the random number generator, and configured to convert the thermometer code into an analog voltage corresponding to the digital signal when the clock signal is in the first state, and to reset the analog voltage to a reset value according to the reset signal when the clock signal is in the second state.
YjcC, a c-di-GMP Phosphodiesterase Protein, Regulates the Oxidative Stress Response and Virulence of Klebsiella pneumoniae CG43
(2013-07-23)
Huang, Ching-Jou
;
Wang, Zhe-Chong
;
Huang, Hsi-Yuan
;
Huang, Hsien-Da
;
Peng, Hwei-Ling
This study shows that the expression of yjcC, an in vivo expression (IVE) gene, and the stress response regulatory genes soxR, soxS, and rpoS are paraquat inducible in Klebsiella pneumoniae CG43. The deletion of rpoS or soxRS decreased yjcC expression, implying an RpoS- or SoxRS-dependent control. After paraquat or H2O2 treatment, the deletion of yjcC reduced bacterial survival. These effects could be complemented by introducing the DyjcC mutant with the YjcC-expression plasmid pJR1. The recombinant protein containing only the YjcC-EAL domain exhibited phosphodiesterase (PDE) activity; overexpression of yjcC has lower levels of cyclic di-GMP. The yjcC deletion mutant also exhibited increased reactive oxygen species (ROS) formation, oxidation damage, and oxidative stress scavenging activity. In addition, the yjcC deletion reduced capsular polysaccharide production in the bacteria, but increased the LD50 in mice, biofilm formation, and type 3 fimbriae major pilin MrkA production. Finally, a comparative transcriptome analysis showed 34 upregulated and 29 downregulated genes with the increased production of YjcC. The activated gene products include glutaredoxin I, thioredoxin, heat shock proteins, chaperone, and MrkHI, and proteins for energy metabolism (transporters, cell surface structure, and transcriptional regulation). In conclusion, the results of this study suggest that YjcC positively regulates the oxidative stress response and mouse virulence but negatively affects the biofilm formation and type 3 fimbriae expression by altering the c-di-GMP levels after receiving oxidative stress signaling inputs.