Browsing by Issue Date, starting with "2012-01-09"

Now showing 1 - 20 of 37481

Reductive catalysis of novel TiO2/Fe-0 composite under UV irradiation for nitrate removal from aqueous solution
(2012-01-09)
Pan, Jill Ruhsing
;
Huang, Chihpin
;
Hsieh, Wen-Pin
;
Wu, Bi-Ju
;
環境工程研究所
Groundwater contaminated by nitrate has become a worldwide problem. Existing technologies for nitrate removal, including zero-valent iron reduction, can only transform nitrate ions to predominantly NH4+. As a result, many studies have concentrated on seeking a solution to convert nitrate to N-2. In this study, the efficiencies of nitrate removal from aqueous solution by single (TiO2 and nano zero valent iron, nZVI), and composite (Nano-TiO2-Fe-0 composite, NTFC) system under UV illumination were prepared. Among the three systems, both nZVI and NTFC can effectively remove nitrate. However, only NTFC can achieve satisfactory transformation of nitrate to N-2. Further investigation has proven that the composition of NTFC (TiO2/nZVI ratio) greatly influences the conversion of nitrate to N-2, which can be attributed to the maintenance of high level of ferrous ions in the NTFC system due to its reducing condition. (C) 2011 Elsevier B.V. All rights reserved.
Silicon introduced effect on resistive switching characteristics of WO(X) thin films
(2012-01-09)
Syu, Yong-En
;
Chang, Ting-Chang
;
Tsai, Tsung-Ming
;
Chang, Geng-Wei
;
Chang, Kuan-Chang
The switching layer with Si interfusion is investigated to improve the electrical characteristics of WO(X) resistance random access memory (RRAM). The WO(X) has attracted extensive attention for RRAM because it can form by converting the surface of the W-plug with a current complementary metal oxide semiconductor (CMOS) compatible thermal oxidation process. In general, the resistance switching behavior of WO(X)-RRAM devices is unstable because the diverse oxidation state provided the stochastic conduction paths. In this research, the Si interfusion can effectively localize the filament conduction path in WO(X) resistance switching layer because the tungsten filament path is limited by SiO(X) in the WSiO(X) film during the forming process. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3676194]
Electrical Probing of Submicroliter Liquid Using Graphene Strip Transistors Built on a Nanopipette
(2012-01-09)
Chen, Chang-Hsiao
;
Lin, Cheng-Te
;
Lee, Yi-Hsien
;
Liu, Keng-Ku
;
Su, Ching-Yuan
Silicon introduced effect on resistive switching characteristics of WOX thin films
(2012-01-09)
Syu, Yong-En
;
Chang, Ting-Chang
;
Tsai, Tsung-Ming
;
Chang, Geng-Wei
;
Chang, Kuan-Chang
The switching layer with Si interfusion is investigated to improve the electrical characteristics of WOX resistance random access memory (RRAM). The WOX has attracted extensive attention for RRAM because it can form by converting the surface of the W-plug with a current complementary metal oxide semiconductor (CMOS) compatible thermal oxidation process. In general, the resistance switching behavior of WOX-RRAM devices is unstable because the diverse oxidation state provided the stochastic conduction paths. In this research, the Si interfusion can effectively localize the filament conduction path in WOX resistance switching layer because the tungsten filament path is limited by SiOX in the WSiOX film during the forming process. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3676194]
Analysis of the association between transcription factor binding site variants and distinct accompanying regulatory motifs in yeast
(2012-01-10)
Chiang, Sufeng
;
Swamy, Krishna B. S.
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Hsu, Ting-Wei
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Tsai, Zing Tsung-Yeh
;
Lu, Henry Horng-Shing
It is generally accepted that genes are regulated by the interactions between transcription factors (TFs) and their binding sites (TFBSs). Some studies have demonstrated that nucleotide variants at variable positions in TFBSs affect yeast gene regulation. Furthermore, variable positions in TFBSs in association with distinct accompanying regulatory motifs of other TFs (i.e., co-TFs) can also impact gene regulation in eukaryotes. Given that, even low-affinity IF-DNA interactions are abundant in vivo; we used both low- and high-affinity TFBSs and performed a genome-wide analysis of associations between variable positions and co-TFs. We found that in Saccharomyces cerevisiae, approximately 14% of the variable positions in TFBSs demonstrate such associations. These associations occurred in close proximity on the same promoters (i.e., highly co-localized). Moreover, such associations were highly conserved between sensu stricto yeasts and also influenced gene expression, which were consistent with enriched functional categories. (C) 2011 Elsevier B.V. All rights reserved.
In Vitro Selection and Characterization of a Novel Zn(II)-Dependent Phosphorothiolate Thiolesterase Ribozyme
(2012-01-10)
Wang, Tzu-Pin
;
Su, Yu-Chih
;
Chen, Yi
;
Liou, Yi-Ming
;
Lin, Kun-Liang
Here we present the in vitro selection of a novel ribozyme specific for Zn(2+)-dependent catalysis on hydrolysis of a phosphorothiolate thiolester bond. The ribozyme, called the TW17 ribozyme, was evolved and selected from an artificial RNA pool covalently linked to a biotin-containing substrate through the phosphorothiolate thiolester bond. The secondary structure for the evolved ribozyme consisted of three major helices and three loops. Biochemical and chemical studies of ribozyme-catalyzed reaction products provided evidence that the ribozyme specifically catalyzes hydrolysis of the phosphorothiolate thiolester linkage. A successful ribozyme construct with active catalysis in trans further supported the determined ribozyme structure and indicated the potential of the ribozyme for multiple-substrate turnover. The ribozyme also requires Zn(2+) and Mg(2+) for maximal catalysis. The TW17 ribozyme, in the presence of Zn(2+) and Mg(2+), conferred a rate enhancement of at least S orders of magnitude when compared to the estimated rate of the uncatalyzed reaction. The ribozyme completely lost catalytic activity in the absence of Zn(2+), like Zn(2+)-dependent protein hydrolases. The discovery and characterization of the TW17 ribozyme suggest additional roles for Zn(2+) in ribozyme catalysts.
Phosphors and lighting apparatus using the same
(2012-01-10)
Chen Teng-Ming
;
Tai Hsiao-Ping
A phosphor has a chemical formula of: Am(Ba1-xEux)nPyOz, wherein A is at least one of the group consisting of Li, Na and K, while 0
k.p WURTZITE HAMILTONIAN AND OPTICAL MATRIX WITH BULK INVERSION ASYMMETRY
(2012-01-10)
Chen, Chun-Nan
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Su, Wei-Long
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Wang, Wan-Tsang
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Jen, Jen-Yi
;
Li, Yiming
A k.p wurtzite Hamiltonian including the bulk (or intracell) inversion asymmetry is developed. Meanwhile, a k.p wurtzite optical matrix including this intracell asymmetry is also established.
記憶體元件及其製作方法
(2012-01-11)
邱碧秀
;
張麗君
;
何嘉政
;
李岱螢
;
沈佑書
本發明係揭露一種記憶體元件及其製造方法。記憶體元件包含基板、絕緣層、第一導電層、鈦酸銅鈣電阻層以及第二導電層。絕緣層形成於基板之上。第一導電層形成於絕緣層之上。鈦酸銅鈣電阻層形成於第一導電層之上。第二導電層形成於鈦酸銅鈣電阻層之上。於製作時，首先，提供基板，接著於基板之上形成絕緣層，之後於絕緣層之上形成第一導電層，然後利用溶膠凝膠法於第一導電層之上形成鈦酸銅鈣電阻層，最後，於鈦酸銅鈣電阻層之上形成第二導電層。本發明不僅符合電子產品低電壓之需求，且能在降低成本的同時，提升產品之可靠度與相容性。
估測人體姿態之方法
(2012-01-11)
陳俊瑋
;
宋開泰
本發明提供一種多人姿態辨識系統。此系統包括人體姿態感測模組、群蜂(Zigbee)無線網路發展板(CC2420DBK board)及電腦端的多人姿態監測軟體。其中人體姿態感測模組由一個三軸加速度計、一個群蜂(Zigbee)晶片及一個8－bit的微控制器所組成。人體姿態感測模組可與CC2420DBK板構成群蜂(Zigbee)無線網路，達到同時觀察多人姿態的效果。該CC2420DBK為群蜂(Zigbee)無線感測網路的接收端，透過RS－232介面將群蜂(Zigbee)無線感測網路中接收到的資訊與機器人或監控電腦溝通。該多人姿態監測軟體則可以同時檢視三位以上使用者的姿態，並對各個使用者的姿態作記錄與統計。本發明並提供一套結合時域分析與小波轉換的人體姿態辨識演算法，實現在人體姿態感測模組的微控制器中。透過此演算法分析三軸的加速度訊號，可辨識跌倒、站、坐、躺、上樓、下樓與走路七種人體姿態。
跨障礙輔助裝置
(2012-01-11)
鄭璧瑩
;
黃健寶
本發明提供一種跨障礙輔助裝置，其係具有一載具本體、一輔助機構以及一感測驅動裝置。該輔助機構係設置於該載具本體之一側，該輔助機構之一端具有一墊塊，該輔助機構係可藉由一調整動作使該墊塊介於該載具本體與一障礙物間，以分段減少該障礙物相對於該載具本體跨越之段差。感測驅動裝置係與該輔助機構相耦接，該感測驅動裝置係藉由感測障礙物是否存在以決定是否驅動該輔助機構產生該調整動作。利用本發明之機制可以分段縮短障礙物之段差高度，使得載具本體得以分段越過障礙物。
移動式電子裝置尋找定點之方法及系統
(2012-01-11)
胡竹生
一種移動式電子裝置尋找定點之方法包含：於一定點發射一音頻訊號；以及以至少二個音頻接收單元接收音頻訊號，並以音頻接收單元間之距離以及音頻訊號分別抵達二個音頻接收單元之距離差來計算出音頻訊號來源之方位角。同時亦揭露一種移動式電子裝置尋找定點之系統。
Surface-Surface Interaction in Smectic Liquid Crystal Films
(2012-01-11)
Pan, LiDong
;
Hsu, C. S.
;
Huang, C. C.
;
應用化學系
;
Department of Applied Chemistry
Null transmission ellipsometry was employed to study the field induced transition of the surface arrangements in freestanding films of smectic liquid crystals. The interlayer interaction between the two surfaces obtained from the threshold voltage for the transition is found to be antiferroelectric and is quasilong ranged. The possible microscopic origins of the measured interaction and its relevance to the interlayer interaction in antiferroelectric liquid crystal materials are discussed.
Session level flow classification by packet size distribution and session grouping
(2012-01-12)
Lu, Chun-Nan
;
Huang, Chun-Ying
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Lin, Ying-Dar
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Lai, Yuan-Cheng
;
資訊工程學系
Classifying traffic into specific network applications is essential for application-aware network management and it becomes more challenging because modern applications complicate their network behaviors. While port number-based classifiers work only for some well-known applications and signature-based classifiers are not applicable to encrypted packet payloads, researchers tend to classify network traffic based on behaviors observed in network applications. In this paper, a session level flow classification (SLFC) approach is proposed to classify network flows as a session, which comprises of flows in the same conversation. SLFC first classifies flows into the corresponding applications by packet size distribution (PSD) and then groups flows as sessions by port locality. With PSD, each flow is transformed into a set of points in a two-dimension space and the distances between each flow and the representatives of pre-selected applications are computed. The flow is recognized as the application having a minimum distance. Meanwhile, port locality is used to group flows as sessions because an application often uses consecutive port numbers within a session. If flows of a session are classified into different applications, an arbitration algorithm is invoked to make the correction. The evaluation shows that SLFC achieves high accuracy rates on both flow and session classifications, say 99.9% and 99.98%, respectively. When SLFC is applied to online classification, it is able to make decisions quickly by checking at most 300 packets for long-lasting flows. Based on our test data, an average of 72% of packets in long-lasting flows can be skipped without reducing the classification accuracy rates. (C) 2011 Elsevier B.V. All rights reserved.
Self-Assembled Poly(ethylene glycol) Buffer Layers in Polymer Solar Cells: Toward Superior Stability and Efficiency
(2012-01-12)
Chien, Shang-Chieh
;
Chen, Fang-Chung
;
Chung, Ming-Kai
;
Hsu, Chain-Shu
;
應用化學系
In this study, we have systematically investigated the mechanism behind the formation of nanoscale self-assembled polymer buffer layers at the cathode interfaces of polymer solar cells. Poly(ethylene glycol) (PEG) molecules in a polymer blend, comprising poly(3-hexylthiophene) and [6,6]-phenyl-C-61-butyric acid methyl ester, spontaneously migrated to the surface where they reacted with the Al cathode to form ohmic contacts. In terms of thermodynamics, the surface energy of the substrates played an important role in triggering the vertical-type morphology. From a kinetics point of view, PEG polymers having lower molecular weights readily underwent vertical phase separation prior to solidification of the polymer films, due to their higher mobilities, whereas PEG polymers of higher molecular weights tended to become trapped in the active layer. Employing this knowledge, we prepared organic photovoltaic cells exhibiting both high efficiency and appreciable improvement in stability.
STATIC RANDOM ACCESS MEMORY WITH DATA CONTROLLED POWER SUPPLY
(2012-01-12)
Chuang Ching-Te
;
Yang Hao-I
;
Hsia Mao-Chih
;
Lin Yung-Wei
;
Lu Chien-Yu
A static random access memory with data controlled power supply, which comprises a memory cell circuit and at least one Write-assist circuit, for providing power to the memory cell circuit according to data to be written to the memory cell circuit.
LOW POWER STATIC RANDOM ACCESS MEMORY
(2012-01-12)
Chuang Ching-Te
;
Yang Hao-I
;
Hsia Mao-Chih
;
Hwang Wei
;
Chen Chia-Cheng
A SRAM that keeps the memory cell array under a low voltage in the Standby mode and Write mode, and raises the memory cell array supply voltage to a high voltage in the Read mode. A SRAM comprising: at least one memory cell circuit, comprising a latch circuit with at least two inverters, and comprising two power receiving terminals for receiving power; and a power supplying circuit, for providing the power to the memory cell circuit, such that the voltages at the power receiving terminals of the latch circuit is below a predetermined voltage level when data is written to the latch circuit. In one embodiment, the memory cell circuit includes a plurality of data accessing terminals and the data accessing terminals are respectively controlled by at least two pass-transistor switch devices.
Histidine-containing Phosphotransfer Protein-B (HptB) Regulates Swarming Motility through Partner-switching System in Pseudomonas aeruginosa PAO1 Strain
(2012-01-13)
Bhuwan, Manish
;
Lee, Hui-Ju
;
Peng, Hwei-Ling
;
Chang, Hwan-You
;
生物科技學系
The histidine-containing phosphotransfer protein-B (HptB; PA3345) is an intermediate protein involved in transferring a phosphoryl group from multiple sensor kinases to the response regulator PA3346 in Pseudomonas aeruginosa PAO1. The objective of this study was to elucidate the biological significance of the HptB-PA3346 interaction and the regulatory mechanisms thereafter. The transcription profiling analysis of an hptB knock-out mutant showed that the expression of a number of motility-related genes was altered consistent with the non-swarming phenotype observed for the mutant. Domain analysis indicated that the PA3346 C-terminal region (PA3346C) exhibits similar to 30% identity with the anti-sigma factor SpoIIAB of Bacillus subtilis. The presence of Ser/Thr protein kinase activity targeting an anti-sigma antagonist, PA3347, at Ser-56 was confirmed in PA3346C using an in vitro phosphorelay assay. Furthermore, PA3346C and the anti-sigma(28) factor FlgM were found to interact with PA3347 individually both in vivo and in vitro. FlgM displaced PA3346C in binding of PA3347 and was then competitively displaced by sigma(28) from the PA3347-FlgM complex, forming a phosphorylation-dependent partner-switching system. The significance of PA3347 phosphorylation in linking the partner-switching system and swarming motility was established by analyzing the swarming phenotype of the PA3347 knock-out mutant and its complement strains.
Non-volatile organic field-effect transistor memory comprising sequestered metal nanoparticles in a diblock copolymer film
(2012-01-14)
Chen, Chia-Min
;
Liu, Chih-Ming
;
Wei, Kung-Hwa
;
Jeng, U-Ser
;
Su, Chiu-Hun
In this study, we fabricated p-channel-type non-volatile organic field-effect transistor (OFET) memory devices featuring an asymmetric PS-b-P4VP diblock copolymer layer incorporating high- and low-work-function metal nanoparticles (NPs) in the hydrophilic and hydrophobic blocks, respectively. We chose the highly asymmetric diblock copolymer PS(56k)-b-P4VP(8k) as the polymer electret to create the memory windows, and used the different work functions of the ex situ-synthesized metal NPs to tune the memory window for either p- or n-channel applications. The transfer curves of non-volatile OFET memory devices incorporating an asymmetric PS(56k)-b-P4VP8k layer embedded with high-work-function Pt NPs (5.65 eV) in the P4VP block exhibited a positive threshold voltage shift and a large memory window (ca. 27 V). In contrast, the transfer curves of the corresponding non-volatile OFET memory devices featuring embedded low-work-function (4.26 eV) Ag NPs exhibited a negative threshold voltage shift and a smaller memory window (ca. 19 V). This approach provides a versatile way to fabricate p- or possibly n-channel-type non-volatile organic field-effect transistor (OFET) memory devices with the same processing procedure.
A new supramolecular film formed from a silsesquioxane derivative for application in proton exchange membranes
(2012-01-14)
Cheng, Chih-Chia
;
Yen, Ying-Chieh
;
Ko, Fu-Hsiang
;
Chu, Chih-Wei
;
Fan, Shih-Kang
A new polyhedral oligomeric silsesquioxane ionomer (HO-doped PUSS-C11-Py) has been investigated. This new ionomer is able to self-assemble through macromers by quadruple hydrogen bonding interactions into a physically crosslinked polymer-like material that can be easily fabricated into films with micro-phase separation. This HCl-doped POSS-C11-Py membrane exhibits higher proton conductivity than a typical Nafion membrane at high temperature, which is extremely rare for a non-sulfonic acid system. This newly developed material may provide an alternative route toward design and fabrication of a new type of proton exchange membranes.