Browsing by Issue Date, starting with "2010-06-15"

Now showing 1 - 20 of 45864

Photocatalysis by Electron Transfer between Different-sized Anatases
(2010-06-15)
Ke, Tsung-Ying
;
Lee, Chi-Young
;
Chiu, Hsin-Tien
;
應用化學系
;
Department of Applied Chemistry
In the solution state, photocatalysis of micro- and nano-sized anatases can be optimized at flat band and in a high pH solution, respectively. Furthermore, a remarkable photocatalyst that can be adopted over a wide range of pH values was produced by mixing commercial micro- and nano-sized anatases. Mixing causes the electron transfer between the identical phase but different-sized TiO(2) particles, subsequently separating the electrons and holes, as well as greatly facilitating photocatalysis. As is well known, the commercially available photocatalyst P25, a mixture of anatase and rutile, achieves a superior photocatalytic performance from pH 3 to 10, owing to the electron transfer between the various phases. This study elucidates these mixed photocatalysts, P25 and mixture of micro and nano-sized anatases. Crown Copyright (C) Published by Elsevier B.V. All rights reserved.
Degradation of carbofuran in aqueous solution by ultrasound and Fenton processes: Effect of system parameters and kinetic study
(2010-06-15)
Ma Ying-Shih
;
Sung Chi-Fanga
;
Lin Jih-Gaw
;
環境工程研究所
;
Institute of Environmental Engineering
To establish an efficient oxidation process for carbofuran degradation, the effects of some operating parameters such as dosages of H(2)O(2), Fe(2+) and initial carbofuran concentrations were observed during carbofuran degradation by the ultrasound process, Fenton process and a combined ultrasound/Fenton process. The degradation kinetics of carbofuran was also examined based on the experimental data. The results show that more than 99% of the carbofuran was degraded by the ultrasound/Fenton process within short reaction time periods. Increased dosages of H(2)O(2) and Fe(2+) enhanced the degradation of carbofuran in the ultrasound and Fenton oxidation processes, but initial carbofuran concentrations decreased carbofuran degradation in both the Fenton and ultrasound/Fenton processes. The degradation kinetics of carbofuran by the three oxidation processes was found to be in accordance with first-order reaction kinetics. The results provide fundamental information about the treatment of carbofuran wastewater and/or other pesticides by the ultrasound/Fenton oxidation process. (C) 2010 Elsevier B.V. All rights reserved.
Remarkable Photothermal Effect of Interband Excitation on Nanosecond Laser-Induced Reshaping and Size Reduction of Pseudospherical Gold Nanoparticles in Aqueous Solution
(2010-06-15)
Werner, Daniel
;
Hashimoto, Shuichi
;
Uwada, Takayuki
;
應用化學系
;
應用化學系分子科學碩博班
An in situ spectroscopic study of the nanosecond laser-induced melting and size reduction of pseudospherical gold nanoparticles with 54 +/- 7 nm diameter allowed the observation of a heating efficiency that was very dependent on the excitation wavelength. A remarkably greater efficiency was observed for the photothermal effect of interband excitation than that of intraband excitation. This noteworthy observation is ascribed to an altered electron heat capacity, c(e), during photoexcitation depending on the excitation energy, which is a phenomenon that has not been realized previously. As a result, a 60% reduction of the specific heat capacity, c(p), compared to that of bulk gold was obtained for interband excitation at 266 nm whereas the c(p) value for the excitation of the intraband transition at 532 nm was unaltered. A semiquantitative explanation was given for this striking phenomenon induced by interband excitation in which excitation relaxation cycles of electrons upon excitation of 5d electrons to the 6sp band lead to a reduced number of electrons contributing to the electron temperature rise in the vicinity of the Fermi level during the nanosecond laser pulse duration. By contrast, electronic-excitation within the 6sp band results in no net reduction in the number of electrons near the Fermi level, giving rise to a value of c(p) similar to that of bulk gold. Our finding that the heat capacity of gold nanoparticles can be changed upon UV laser excitation is important for understanding the fundamental nature of noble metal nanoparticles. Furthermore, this finding might be useful for preparing new metal alloy particles as well as for manipulating the thermodynamic properties of the nanoparticles.
Star Block Copolymers Through Nitroxide-Mediated Radical Polymerization From Polyhedral Oligomeric Silsesquioxane (POSS) Core
(2010-06-15)
Lu, Chu-Hua
;
Wang, Jui-Hsu
;
Chang, Feng-Chih
;
Kuo, Shiao-Wei
;
應用化學系
A series of star block copolymers were prepared through nitroxide-mediated radical polymerization (NMRP) from polyhedral oligomeric silsesquioxanes (POSS) nanoparticle by core-first polymerization. Eight N-alkoxyamine groups were incorporated onto the eight corners of a POSS cube through quantitative hydrosilylation through addition of octakis(dimethylsiloxy)silsesquioxane (O(8)M(8)(H) POSS) with 1-(2-(allyloxy)-1-phenylethoxy)-2,2,6,6-tetramethyl-piperidine (allyl-TEMPO) and Karstedt's agent (a platinum divinylsiloxane complex) was used as a catalyst. Octa-N-alkoxyamines POSS (OT-POSS) were used as platform to synthesize star polystyrene-POSS ((PS)(8)-POSS) homopolymer and diblock copolymers of poly(styrene-block-4-vinyl-pyridine)-POSS ((PS-b-P4VP)(8)-POSS) and poly(styrene-block-acetoxystyrene) ((PS-b-PAS)(8)-POSS) through NMRP. In addition, subsequent selective hydrolysis of the acetyl protective group of (PS-b-PAS)(8)-POSS, the poly(styrene-block-vinyl phenol) ((PS-b-PVPh)(8)-POSS) with strong hydrogen bonding group was obtained. The detailed chemical structure and self-assembled structures of these star block copolymers based on POSS were characterized by (1)H NMR, FTIR, SEC, TEM, and SAXS analyses.
Co-existence of anammox and denitrification for simultaneous nitrogen and carbon removal-Strategies and issues
(2010-06-15)
Kumar, Mathava
;
Lin, Jih-Gaw
;
環境工程研究所
;
Institute of Environmental Engineering
The discovery of anaerobic ammonium oxidation (anammox) has greatly improved the understanding of the nitrogen cycle. Anammox provides great promise for the removal of nitrogen from wastewater, containing high concentration of ammonium. However, the presence of organic carbon is considered as unfavorable to this autotrophic process, i.e. anammox. Most of the real wastewaters contain both organic carbon and nitrogen. Under this circumstance, several processes have been established primarily for the complete removal of organic carbon. Subsequently, the wastewater containing no or low organic carbon and nitrogen is treated via a variety of nitrogen removal processes. The co-existence of anammox and denitrification could be useful for the simultaneous removal of nitrogen and organic carbon in a single system rather than a sequential chain of treatment. This review addresses the microbiology, strategies, consequences and the future research challenges in the co-existence of anammox and denitrification. (C) 2010 Elsevier B.V. All rights reserved.
Unitary part of a contraction
(2010-06-15)
Gau, Hwa-Long
;
Wu, Pei Yuan
;
應用數學系
;
Department of Applied Mathematics
For a contraction A on a Hilbert space H, we define the index j(A) (resp.. k(A)) as the smallest nonnegative integer j (resp., k) such that ker(I - A(j)*A(j)) (resp., ker(I - A(k)*A(k)) boolean AND ker(I - A(k)*A(k)*)) equals the subspace of H on which the unitary part of A acts. We show that if n = dim H < infinity, then j(A) <= n (resp., k(A) <= left particularn/2left particular). and the equality holds if and only if A is of class S, (resp., one of the three conditions is true: (1) A is of class S, (2) n is even and A is completely nonunitary with parallel to A(n-2)parallel to = 1 and parallel to A(n-1)parallel to < 1. and (3) n is even and A = U circle times A', where U is unitary on a one-dimensional space and A' is of class S(n-1)). (C) 2010 Elsevier Inc. All rights reserved.
Dynamic manipulation and patterning of microparticles and cells by using TiOPc-based optoelectronic dielectrophoresis
(2010-06-15)
Yang, Shih-Mo
;
Yu, Tung-Ming
;
Huang, Hang-Ping
;
Ku, Meng-Yen
;
Hsu, Long
We develop light-driven optoelectronic tweezers based on the organic photoconductive material titanium oxide phthalocyanine. These tweezers function based on negative dielectrophoresis (nDEP). The dynamic manipulation of a single microparticle and cell patterning are demonstrated by using this light-driven optoelectronic DEP chip. The adaptive light patterns that drive the optoelectronic DEP onchip are designed by using Flash software to approach appropriate dynamic manipulation. This is also the first reported demonstration, to the best of our knowledge, for successfully patterning such delicate cells from human hepatocellular liver carcinoma cell line HepG2 by using any optoelectronic tweezers. (C) 2010 Optical Society of America
Leakage current cut-off device for ternary content addressable memory
(2010-06-15)
Huang
;
Po-Tsang
;
Liu
;
Wen-Yen
;
Hwang
A leakage current cut-off device for a ternary content addressable memory is provided. The storage cell of a ternary content addressable memory may be in the active mode, data-retention mode and cut-off mode. This invention applies a multi-mode data retention power gating device to the storage cell of the ternary content addressable memory to reduce the leakage current through the storage cell in the data-retention mode and the cut-off mode, and support the full speed operation in the active mode.
Study of InGaN-GaN Light-Emitting Diodes With Different Last Barrier Thicknesses
(2010-06-15)
Chen, Jun-Rong
;
Lu, Tien-Chang
;
Kuo, Hao-Chung
;
Fang, K. L.
;
Huang, K. F.
This work reports a theoretical and experimental study on the device performance of blue InGaN-GaN light-emitting diodes (LEDs) with different last barrier thicknesses. The experimental results show that the employment of a 25-nm-thick p-type GaN last barrier in GaN LEDs can improve the light output power from 35.6 to 40.2 mW at 50 mA. By using advanced device simulation, it is shown that the effective energy barrier created by the p-type AlGaN electron blocking layer (EBL) is significantly decreased due to the band bending at the interface between GaN last barrier and AlGaN EBL. The use of a p-type GaN last barrier before the growth of AlGaN EBL can provide a higher energy barrier to suppress the electron overflow and then enhance the light output power.
Effects of static magnetic fields on the development and aging of Caenorhabditis elegans
(2010-06-15)
Hung, Yao-Ching
;
Lee, Jia-Huey
;
Chen, Huang-Meng
;
Huang, Guewha Steven
;
材料科學與工程學系奈米科技碩博班
The current study investigated the possible effects of static magnetic fields (SMFs) on the developmental and aging processes of Caenorhabditis elegans. Nematodes were grown in the presence of SMFs of strengths varying from 0 to 200 mT. The rate of development and the lifespan were recorded. Treatment with a 200 mT SMF reduced the development time from the L2 to the L3 stage by 20%, from L3 to L4 by 23%, and from L4 to young adult by 31%. After SMF treatment, the average lifespan was reduced from 31 days to 24 days for wild-type nematodes. The up-regulation of clk-1, lim-7, daf-2, unc-3 and age-1 after SMF treatment was verified by quantitative real-time RT-PCR. Apparently, induction of gene expression is selective and dose dependent. The total developmental time was significantly reduced for the lin-4, lin-14, lin-41 and lim-7 mutants, but not for the let-7, clk-1, unc-3 and age-1 mutants. Lifespan analyses revealed that the let-7, unc-3 and age-1 mutants were not affected by SMF treatment. Here we show that SMFs accelerate nematode development and shorten nematode lifespan through pathways associated with let-7, clk-1, unc-3 and age-1.
有機光電元件
(2010-06-16)
孟心飛
;
洪勝富
;
曾信榮
;
李冠成
一種有機光電元件,包括第一電極;形成於該第一電極上之主動層;形成於該主動層上之第二中間層;以及形成於該第二中間層上之第二電極;其中,該第二中間層包括含有第二聚合物和第二有機小分子的第二混合物,且該第二有機小分子係選自電洞傳輸材料、電子傳輸材料、電子阻擋材料或電洞阻擋材料。本發明之有機光電元件係以溶液製程製備而得,具有製程簡便、改善薄膜成膜性和提升元件效率之優點。
自動棋譜產生系統及其方法
(2010-06-16)
莊仁輝
;
羅國華
;
許諾白
;
吳毅成
一種自動棋譜產生方法，找出攝影機所拍攝之棋盤影像中的棋子區域，並由棋盤影像判定是否有異動之棋子；並依照棋子的先後順序建立棋盤上所有棋子在影像中的位置相對關係，再藉由此位置相對關係資訊重建棋盤的座標系與各棋子之位置及思考時間，此自動棋譜產生方法可免除因需偵測棋盤格線所可能造成的困擾與誤差，並獲得一準確的電子棋譜。
重估一通道脈衝響應之方法、裝置及其電腦程式產品
(2010-06-16)
吳文榕
;
賴允仁
一種重估一通道脈衝響應之方法、裝置及電腦程式產品。該通道脈衝響應包含複數個通道切片,且對應至一通道頻率響應。該方法包含下列步驟:選取該等通道切片其中之一以作為一選定通道切片,其餘作為至少一待處理通道切片;扣除該至少一待處理通道切片對該通道頻率響應之影響,以得一第一通道頻率響應;以一最小平方法及該第一通道頻率響應,更新該選定通道切片;以及將該選定通道切片置換為更新後之該選定通道切片。藉此,可提高通道估測的準確度。
具色彩轉換層之有機電發光裝置
(2010-06-16)
張繼聖
;
劉柏村
;
陳金鑫
本發明係揭露一種具色彩轉換層之有機電發光裝置,其包含一有機電發光元件,其特徵在於係將有機電發光元件搭配一外部色彩轉換層(External color tuning layer)以形成白光有機發光裝置。本發明係將色彩轉換材料溶解於具有高透明度的PMMA溶液中,而後塗佈於有機電發光元件之出光面側以產生白光。此技術提供一簡化的方法以製作有機電發光裝置,並搭配一般多波段的白光有機電發光裝置,其具有一進一步降低操作電壓及提高功率效率之功用。
一種鈣鈦礦氧化物觸媒的製備方法
(2010-06-16)
吳樸偉
;
張雲閔
本發明係提供一種La0.6Ca0.4Co1-xIrx2O3 (x=0~1)鈣鈦礦氧化物觸媒的製備方法。該觸媒在鹼性系統中，同時具有優良的氧氣生成與還原反應雙功能催化能力。使用固態燒結法(Solid State Reaction Method)，且以檸檬酸鹽法(Amorphous Citrate Precursor)與機械研磨法(Mechanical Alloying)以製備鈣鈦礦觸媒。此觸媒的電化學活性，相對於傳統La0.6Ca0.4CoO3，不論是電流對電壓曲線、定電流放電或定電流充電，不僅能有效地降低電流對電壓的損失，更能有效地提升電化學性能。
音波感知功能之安全帽
(2010-06-16)
楊耀民
一種具音波感知功能之安全帽，係包括音波裝置、訊號處理裝置、狀態表現裝置與電力供應裝置，經該音波裝置中的音波發射模組發出感測音波，由該音波裝置中的音波接收模組接收感測音波，而由該訊號處理裝置處理感測音波，並控制該狀態表現裝置，使該狀態表現裝置產生相對應的狀態;藉此，用車人可以經由該具音波感知功能之安全帽，而主動且輕鬆地了解到車子的後方或是左、右二側後方的車輛方位，減少騎車分心的狀況，有效降低因此造成的用路人風險，大幅提高整體道路安全。
DISPLAY
(2010-06-17)
Fan, Shih-Kang
;
Chiu, Cheng-Pu
;
Hsu, Ching-Hsiang
;
Mo, Chi-Neng
;
Chiang, Mei-Tsao
A display includes a first substrate, a first electrode, a second substrate, a second electrode and a display material layer. The first electrode is disposed on the first substrate and the second electrode is disposed on the second substrate. The display material layer is disposed between the first electrode and the second electrode. The display material layer of the invented display includes a solution and a plurality of first micro beads, wherein each of the first micro beads further has a plurality of different axis lengths in different axis directions, and the axis length in at least an axis direction is different from the axis lengths in the rest axis directions so that the first micro beads present different arrangement densities in different driving frequencies under the influence of polarized self-arrangement effect.
Disrupted long-range spin-spiral ordering and electric polarization in the Zn-substituted quantum helimagnet LiCu2-xZnxO2
(2010-06-18)
Hsu, H. C.
;
Lee, W. L.
;
Lin, J. -Y.
;
Liu, H. L.
;
Chou, F. C.
Long-range spin-spiral ordering in quantum quasi-two-dimensional helimagnet LiCu2O2 is destroyed by similar to 8% Zn2+ substitution and a magnetic anomaly near similar to 14 K of different character emerges. Zn substitution may have introduced either a magnetic ground state of spin glass in nature, antiferromagnetic ordering with complex easy-plane anisotropy, or a gapped phase which is phase separated and proportional to the Zn substitution level on a short-range ordered background. The magnetic ground state is modified at the same time that the electric polarization disappears.
Disrupted long-range spin-spiral ordering and electric polarization in the Zn-substituted quantum helimagnet LiCu(2-x)Zn(x)O(2)
(2010-06-18)
Hsu, H. C.
;
Lee, W. L.
;
Lin, J. -Y.
;
Liu, H. L.
;
Chou, F. C.
Long-range spin-spiral ordering in quantum quasi-two-dimensional helimagnet LiCu(2)O(2) is destroyed by similar to 8% Zn(2+) substitution and a magnetic anomaly near similar to 14 K of different character emerges. Zn substitution may have introduced either a magnetic ground state of spin glass in nature, antiferromagnetic ordering with complex easy-plane anisotropy, or a gapped phase which is phase separated and proportional to the Zn substitution level on a short-range ordered background. The magnetic ground state is modified at the same time that the electric polarization disappears.
Au-decorated Na(x)H(2-x)Ti(3)O(7) nanobelts exhibiting remarkable photocatalytic properties under visible-light illumination
(2010-06-18)
Pu, Ying-Chih
;
Chen, Yu-Chih
;
Hsu, Yung-Jung
;
材料科學與工程學系
;
Department of Materials Science and Engineering
We demonstrated for the first time that Na-intercalated H(2)Ti(3)O(7) (Na(x)H(2-x)Ti(3)O(7)) NBs, prepared in the typical alkaline hydrothermal process, can effectively absorb visible light to carry out photocatalytic reactions. With the capability of effective light absorption in visible range, Na(x)H(2-x)Ti(3)O(7) NBs performed much better in the photoclegradation of thionine than the other three counterpart products including H(2)Ti(3)O(7), mixed Na(2)Ti(6)O(13)/TiO(2) and anatase TiO(2) under visible-light irradiations. As compared to the relevant commercial products like P-25 TiO(2) and Na(2)Ti(3)O(7) powders, the as-synthesized Na(x)H(2-x)Ti(3)O(7) NBs exhibited superior photocatalytic efficiency under UV illumination, demonstrating their potential as an efficient photocatalyst in relevant redox reactions. A further enhancement in the photocatalytic activity can be achieved for Na(x)H(2-x)Ti(3)O(7) NBs when Au nanoparticles of suitable amount were deposited on their surfaces. This improvement is due to the band offsets between Na(x)H(2-x)Ti(3)O(7) and Au, which may promote charge carrier separation to favor the photocatalysis. The recycling test reveals that Au-decorated Na(x)H(2-x)Ti(3)O(7) NBs could be promisingly utilized in the long-term course of photocatalysis. Furthermore, the result of performance evaluation under natural sunlight shows that the current Au-decorated Na(x)H(2-x)Ti(3)O(7) NBs can be used as highly efficient photocatalysts which may practically harvest energy from sunlight. (C) 2010 Elsevier B.V. All rights reserved.