Browsing by Issue Date, starting with "2017-10-19"

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交大e-News第242期-培養「非」型人才交通大學成立百川學士學位學程
(2017-10-19)
國立交通大學秘書室
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Secretariat
Anisotropic Electric Field Effect on the Photoluminescence of CH3NH3PbI3 Perovskite Sandwiched between Conducting and Insulating Films
(2017-10-19)
Awasthi, Kamlesh
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Wang, Chi-Yung
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Fathi, Amir
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Narra, Sudhakar
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Diau, Eric Wei-Guang
Photoluminescence (PL) of a nanocrystalline film of methylammonium lead iodide perovskite (MAPbI(3)) sandwiched between an electrode of a fluorine-doped tin oxide (FTO) layer and an insulating film of poly(methyl methacrylate) is found to increase and decrease significantly with the application of an external electric field (F-ext), depending on the direction of the applied field, based on the measurements of electrophotoluminescence (E-PL) spectra, i.e., field-induced change in PL spectra. The field-induced change in PL intensity is confirmed to originate from the field-induced change in the number of free carriers which induce radiative recombination, based on temporally resolved E-PL measurements. We propose that an internal field (F-int) exists even without application of F-ext. The anisotropic behavior of the effect of F-ext on PL is interpreted in terms of a synergy effect of F-int and F-ext; both fields are additive with the applied field direction from Ag to FTO electrode (positive direction) or subtractive with the opposite applied field direction (negative direction), where FTO is the positive electrode, resulting in an increased or decreased total electric field as well as quenching or enhancement of PL, respectively. The PL lifetime in the nanosecond region increased and decreased with an application of an electric field in the positive and negative directions, respectively, which is attributed to a field-induced change in the concentration of free carriers.
COMMUNICATION SYSTEM AND CHANNEL ESTIMATING METHOD THEREOF
(2017-10-19)
David W. LIN
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Yen-Kai WANG
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Yu-Sheng GUO
A communication system includes at least one transmitting unit and at least one receiving unit. The at least one transmitting unit is configured to transmit at least one input signal after precoding it with at least one precoding matrix. The at least one receiving unit wirelessly coupled with the at least one transmitting unit is configured to receive the at least one precoded input signal, and generate at least one channel quality signal corresponding to the at least one precoded input signal, in which the at least one transmitting unit generates at least one magnitude information estimate or at least one phase information estimate or at least one of both for at least one channel state information according to the at least one channel quality signal, the at least one precoding matrix and at least one noise size signal.
Structural and Photophysical Properties of Methylammonium Lead Tribromide (MAPbBr(3)) Single Crystals
(2017-10-20)
Wang, Kai-Hung
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Li, Liang-Chen
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Shellaiah, Muthaiah
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Sun, Kien Wen
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應用化學系
The structural and photophysical characteristics of MAPbBr(3) single crystals prepared using the inverse temperature crystallization method are evaluated using temperature-dependent X-ray diffraction (XRD) and optical spectroscopy. Contrary to previous research reports on perovskite materials, we study phase transitions in crystal lattice structures accompanied with changes in optical properties expand throughout a wide temperature range of 300-1.5 K. The XRD studies reveal several phase transitions occurred at similar to 210 K, similar to 145 K, and similar to 80 K, respectively. The coexistence of two different crystallographic phases was observed at a temperature below 145 K. The emission peaks in the PL spectra are all asymmetric in line shape with weak and broad shoulders near the absorption edges, which are attributed to the Br atom vacancy on the surface of the crystals. The time-resolved PL measurements reveal the effect of the desorption/adsorption of gas molecules on the crystal surface on the PL lifetimes. Raman spectroscopy results indicate the strong interplays between cations and different halide atoms. Lastly, no diamagnetic shift or split in emission peaks can be observed in the magneto-PL spectra even at an applied magnetic field up to 5 T and at a temperature as low as 1.5 K.
Structure-Property Relationship Study of Donor and Acceptor 2,6-Disubstituted BODIPY Derivatives for High Performance Dye-Sensitized Solar Cells
(2017-10-20)
Yeh, Shih-Chieh
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Wang, Li-Jing
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Yang, Hong-Ming
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Dai, Yu-Huei
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Lin, Chao-Wen
Seven donor and acceptor 2,6-disubstituted 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) dyes have been synthesized and characterized. Including MPBTCA, which is a known compound, the seven BODIPY dyes have been characterized by varied physical methods, such as UV/Visible absorption spectroscopy, low energy photo-electron spectroscopy (AC-2), and HOMO-LUMO DFT/TDDFT calculation. All seven BODIPY dyes have absorption lambda(max) around 535-545 nm, which is significantly longer than 499 nm of 4,4-difluoro-1,3,5,7,8-pentamethyl-4-bora-3a,4a-diaza-s-indacene (PM 546). Having structural variation on donor group, acceptor group, donor pi-spacer, acceptor pi-spacer, and the substituent on boron, some BODIPY dyes exhibit small extinction coefficients or spectral integrals in solution (MPCtBTCA, MPBT-pyO, MPBTT-pyO, MTBTCA), broadening absorption spectral profile (MTBTCA), weak intramolecular charge transfer characteristics (MPBT-pyO, MPBTT-pyO, MTBTCA), too low LUMO energy level (PPBTCA), or insufficient dye-uptake by TiO2 FTO (MPBT-pyO, MPBTT-pyO, MTBTCA). Two of the seven BODIPY dyes, MPBTCA and MPBTTCA, do not show the adverse properties like other BODIPY dyes. With our improved TiO2 FTO (fluorine doped tin oxide) dyeing method, namely a solution dropping method, high performance dye-sensitized solar cells (DSCs) have been realized by MPBTCA and MPBTTCA photosensitizers. Power conversion efficiencies of 6.3 and 6.4% have been achieved by MPBTCA and MPBTTCA DSCs, respectively. To the best of our knowledge, MPBTCA and MPBTTCA are the most efficient dyes for the donor and acceptor 2,6-disubstituted BODIPY DSCs so far.
Infrared absorption spectra of partially deuterated methoxy radicals CH2DO and CHD2O isolated in solid para-hydrogen
(2017-10-21)
Haupa, Karolina A.
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Johnson, Britta A.
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Sibert, Edwin L., III
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Lee, Yuan-Pern
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應用化學系
The investigation of partially deuterated methoxy radicals is important because the symmetry lowering from C-3v to C-s provides new insights into the couplings between rovibronic states via Jahn-Teller and spin-orbit interactions. The vibrational spectrum of the partially deuterated methoxy radical CH2DO in a matrix of p-H-2 has been recorded. This species was prepared by irradiating a p-H-2 matrix containing deuterated d1-nitritomethane (CH2DONO) at 3.3 K with laser light at 355 nm. The identification of the radical is based on the photochemical behavior of the precursor and comparison of observed vibrational wavenumbers and infrared (IR) intensities with those predicted from a refined quartic, curvilinear, internal coordinate force field calculated with the coupled-cluster singles and doubles with perturbative triples/cc-pVTZ method. CH2DO reacts with H-2 with a rate coefficient (3.5 +/- 1.0) x 10(-3) s(-1). Predominantly c-CHDOH and a negligibly small amount of t-CHDOH were produced. This stereoselectivity results from the reaction H + C-s-CH2DOH, which was demonstrated by an additional experiment on irradiation of a CH2DOH/Cl-2/p-H-2 matrix with ultraviolet and IR light to induce the H + CH2DOH reaction; only c-CHDOH was observed from this experiment. Even though the energies of transition states and products for the formation of c-CHDOH and t-CHDOH differ by only similar to 10 cm(-1), the selective formation of c-CHDOH can be explained by tunneling of the hydrogen atom via an optimal tunneling path. Similarly, the vibronic spectrum for the partially deuterated specie d(2)-methoxy radical (CHD2O) was obtained upon irradiation of d(2)-nitritomethane (CHD2ONO) at 355 nm. Lines associated with the fundamental vibrational modes were observed and assigned; line positions agree with theoretically predicted vibrational wavenumbers. CHD2O reacts with H-2 with a rate coefficient (6.0 +/- 1.4) x 10(-3) s(-1); CD2OH was produced as a major product because the barrier for the formation of CHDOH from H + CHD2OH is greater by similar to 400 cm(-1). Rate coefficients of the decays of CH3O, CH2DO, CHD2O, and CD3O and their corresponding potential energy surfaces are compared. Published by AIP Publishing.
Multifunctional nanoparticles with controllable dimensions and tripled orthogonal reactivity
(2017-10-21)
Wu, Chih-Yu
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Chang, Chun-Wei
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Yuan, Ruei-Hung
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Chiang, Yu-Chih
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Chen, Jiun-Tai
Multifunctional nanoparticles featuring three distinct and orthogonal functionalities for performing catalyst-free click reactions of azide-alkyne and maleimide-thiol and atom transfer radical polymerization (ATRP) are fabricated using a simple chemical vapor deposition copolymerization approach with the flexibility to control the particle size and geometry.
最純真的微笑　熊米屋小愉兒餅乾
(2017-10-22)
蔡亞融
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Department of Communication and Technology
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傳播與科技學系
熊米屋是小愉兒（喜憨兒）親自手作的烘焙坊。但由於目前尚無實體店，他們藉由走出台北捷運街頭推廣叫賣，讓更多人認識熊米屋小愉兒的餅乾。
願這一切都不會失去
(2017-10-22)
關子茵
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Department of Communication and Technology
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傳播與科技學系
想家了，請關注遊子們的思鄉病。
浪浪別哭　讓愛不再流浪
(2017-10-22)
蔡璨竹
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Department of Communication and Technology
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傳播與科技學系
「浪浪別哭」，一間結合動物中途之家的咖啡廳，用滿滿的愛，幫助浪浪們找到適合自己的家。
政治場域的舞台鬥爭
(2017-10-22)
王毓楷
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Department of Communication and Technology
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傳播與科技學系
學校究竟是否屬於政治場域的一環，或許同言論自由與意識型態的權衡一樣難以定論。
安靜的鋒芒　為內向者除去污名
(2017-10-22)
簡梵軒
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Department of Communication and Technology
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傳播與科技學系
在講求競爭與速度的現代社會下，外向者特質較受推崇，然而近幾年內向者的價值也逐漸受到注目與肯定，本文藉由分析雙方差異，探討兩者的特質與重要性。
總編輯的話
(2017-10-22)
簡文怡
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Department of Communication and Technology
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傳播與科技學系
本期為喀報271期，各類目稿件平均。本期頭題提及花磚文化的保存，其餘報導則以不同體裁切入科技隱憂、弱勢族群等議題。
張馥　從零追求藝術的女孩
(2017-10-22)
陳品文
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Department of Communication and Technology
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傳播與科技學系
一顆沉睡已久的心如何甦醒，一步步帶領張馥走向藝術的殿堂。
無家者　那些在街頭流浪的人們　
(2017-10-22)
戴葦婷
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Department of Communication and Technology
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傳播與科技學系
無家者是從社會安全網上落下來的人們，理解並包容是幫助他們的開始。
擁抱新科技之前　請先抱持懷疑
(2017-10-22)
葉宜瑩
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Department of Communication and Technology
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傳播與科技學系
在科技蓬勃發展的現在，我們做好迎接的準備了嗎？透過刀劍神域序列爭戰，思考我們即將面臨的未來。
大溪老街　人文薈萃之地
(2017-10-22)
戴淨妍
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Department of Communication and Technology
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傳播與科技學系
桃園大溪是個人文薈萃之地，保留了台灣各個時期歷史印跡。
那些說不出口的愛
(2017-10-22)
王貞懿
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Department of Communication and Technology
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傳播與科技學系
說不出口，不是因為不愛，而是這就是我們表達愛的方式，只是蹩腳了點。
走慢了時間　心靈更富有
(2017-10-22)
黃珮瑄
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Department of Communication and Technology
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傳播與科技學系
張西作的第二本書《你走慢了我的時間》，以故事貿易的模式與陌生人交換心情，字句深刻雋永。
田裡有喵　循環農業再造計畫
(2017-10-22)
顏維萱
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Department of Communication and Technology
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傳播與科技學系
介紹「田裡有喵」貓糞堆肥研究計畫，以「貓便當土」作為出發點，讓貓咪們自給自足的同時，達到提倡循環農業的目的。