Browsing by Issue Date, starting with "2018-12-04"

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Automated Dual-Chamber Sampling System to Follow Dynamics of Volatile Organic Compounds Emitted by Biological Specimens
(2018-12-04)
Chang, Cheng-Hao
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Urban, Pawel L.
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應用化學系
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Department of Applied Chemistry
Growth of microorganisms is often accompanied by the release of volatile organic compounds (VOCs). The released VOCs may qualitatively or quantitatively reflect the physiological states of microbial cultures. A number of VOCs are produced during microbial degradation of organic matter accompanying food spoilage. In order to characterize the dynamics of microbial VOC production, and enable time-dependent analysis, we have constructed a dual-chamber sampling system and coupled it online with mass spectrometry (MS). The biological specimen is placed in a gas-tight sampling chamber. A carrier gas is introduced to the chamber periodically to transfer the VOCs present in the specimen headspace to the atmospheric-pressure chemical-ionization interface of a triple-quadrupole mass spectrometer. A control or blank spectrum is recorded before the specimen spectrum is recorded at each time point, enabling signal comparison and subtraction. The custom-made electronic control unit, incorporating three Arduino microcontrollers, operates six pinch valves and a miniature air compressor and triggers MS-data acquisition. The automated dual-chamber sampling system was first tested using standard mixtures to verify its analytical performance. To demonstrate the usefulness of this system in the studies of microbial volatomes, we implemented it in real-time monitoring of the growth of bakers yeast (Saccharomyces cerevisiae), fructification of golden oyster mushroom (Pleurotus citrinopileatus), and microbial degradation of a food-related sample (Pacific white shrimp, Litopenaeus vannamei). The recorded VOC signals show characteristic temporal profiles with transient bands or plateaus corresponding to different stages of microbial growth and putrefaction processes.
A Novel Selective JAK2 Inhibitor Identified Using Pharmacological Interactions
(2018-12-04)
Lin, Tony Eight
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HuangFu, Wei-Chun
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Chao, Min-Wu
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Sung, Tzu-Ying
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Chang, Chao-Di
The JAK2/STAT signaling pathway mediates cytokine receptor signals that are involved in cell growth, survival and homeostasis. JAK2 is a member of the Janus kinase (JAK) family and aberrant JAK2/STAT is involved with various diseases, making the pathway a therapeutic target. The similarity between the ATP binding site of protein kinases has made development of specific inhibitors difficult. Current JAK2 inhibitors are not selective and produce unwanted side effects. It is thought that increasing selectivity of kinase inhibitors may reduce the side effects seen with current treatment options. Thus, there is a great need for a selective JAK inhibitor. In this study, we identified a JAK2 specific inhibitor. We first identified key pharmacological interactions in the JAK2 binding site by analyzing known JAK2 inhibitors. Then, we performed structure-based virtual screening and filtered compounds based on their pharmacological interactions and identified compound NSC13626 as a potential JAK2 inhibitor. Results of enzymatic assays revealed that against a panel of kinases, compound NSC13626 is a JAK2 inhibitor and has high selectivity toward the JAK2 and JAK3 isozymes. Our cellular assays revealed that compound NSC13626 inhibits colorectal cancer cell (CRC) growth by downregulating phosphorylation of STAT3 and arresting the cell cycle in the S phase. Thus, we believe that compound NSC13626 has potential to be further optimized as a selective JAK2 drug.
交大e-News第268期-2018 WRO機器人大賽交大金包銀勇奪世界冠亞
(2018-12-05)
國立交通大學秘書室
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Secretariat
Improved Thermal Stability and Stress Immunity in Highly Scalable Junctionless FETs Using Enhanced-Depletion Channels
(2018-12-05)
Liu, Chien
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Cheng, Chun-Hu
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Lin, Ming-Huei
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Shih, Yi-Jia
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Hung, Yu-Wen
In this work, we report a novel multi-PNPN-channel junctionless transistor with short channel length of 60nm. The multi-PNPN junctionless transistor exhibits the larger drive current of > 1 mu A/mu m, the steeper turn-on switching of 77 mV/decade, and the higher on/off current ratio of > 10(7) than the hybrid PN channel device under the same gate overdrive. The improved performance is mainly attributed to the enhanced depletion effect of multi-PNPN channel to optimize the electric field modification of surface p-channel. The stronger immunity to constant-voltage stress is also obtained for multi-PNPN channel due to the lower lateral electric field near drain side to reduce the impact ionization ratio. (C) 2018 The Electrochemical Society.
New Helicene-Type Hole-Transporting Molecules for High-Performance and Durable Perovskite Solar Cells
(2018-12-05)
Lin, Yeo-Sin
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Abate, Seid Yimer
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Lai, Kuan-Wen
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Chu, Chih-Wei
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Lin, Yan-Duo
Three azahelicene derivatives with electron-rich bis(4-methoxyphenyl)amino or bis(p-methoxyphenyl)aminophenyl groups at the terminals were deliberately designed, synthesized, and characterized as hole-transporting materials (HTMs) for perovskite solar cells (PSCs). Optical and thermal properties, energy level alignments, film morphologies, hole extraction ability, and hole mobility were studied in detail. PSCs using the newly synthesized molecules as HTMs were fabricated. A maximum power conversion efficiency (PCE) of 17.34% was observed for the bis(p-methoxyphenyl)amino-substituted derivative (SY1) and 16.10% for the bis(p-methoxyphenyeaminophenyl-substituted derivative (SY2). Longer-chain substituent such as hexyloxy group greatly diminishes the efficiency. In addition, the dopant-free devices fabricated with SY1 as the HTM shows an average PCE of 12.13%, which is significantly higher than that of spiro-OMeTAD (7.61%). The ambient long-term stability test revealed that after 500 h, the devices prepared from SY1 and SY2 retained more than 96% of its initial performance, which is much improved than the reference device with standard spiro-OMeTAD as the HTM under the same conditions. Detailed material cost analysis reveals that the material cost for SY1 is less than 8% of that for spiro-OMeTAD. These results provide a useful direction for designing a new class of HTMs to prepare highly efficient and more durable PSCs.
Facially Polarized Molecule for Alkalides and Superalkalides with Considerable Nonlinear Optical Response
(2018-12-06)
Li, Bo
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Peng, Daoling
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Gu, Feng Long
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Zhu, Chaoyuan
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應用化學系
In this work, alkali M (Li and K) and superalkali M ' O-3 (M '=Li and Na) combined with facially polarized molecule, all-cis 1,2,3,4,5,6-Hexafluorocyclohexane (L, C6H6F6), were utilized to design novel alkalides L-M-L-M ' and superalkalides L-M-L-M ' O-3, respectively. Computational results show that alkalides L-M-L-M ' and superalkalides L-M-L-M ' O-3 have high thermodynamic stability, and the superalkalides L-M-L-M ' O-3 are more stable than the alkalides L-M-L-M '. Importantly, they also possess remarkable NLO responses, the electronic contribution of the static first hyperpolarizability (beta(e)(0)) has upped to 3.42x10(6) (a.u.) for L-K-L-Li3O. In particularly, the number of ligand L considerably impacts on beta(e)(0) value, namely, the beta(e)(0) value of Li-L-Li3O can be improved two orders of magnitude by adding additional ligand L, 1.31x10(6) (a.u.)(L-Li-L-Li3O) > 7.76x10(4) (a.u.)(Li-L-Li3O). We hope this work can attract researchers to design and synthesize novel excess electron compounds with high performance NLO materials.
FUEL CELL SYSTEM
(2018-12-06)
Tsung-Lin CHEN
;
Chien-Chang WU
A fuel cell system includes a comparator, a signal tracking controller, a first load distribution controller, a first loop gain controller, a first adder, a first PWM controller, a first fuel cell and power converter, a second load distribution controller, a second loop gain controller, a second adder, a second PWM controller, and a second fuel cell and power converter. According to the fuel cell system, each fuel cell connected in parallel can have a different output voltage, and the output power of each fuel cell can be controlled, so that the voltage at the load side can be maintained and the power output ratio of each fuel cell can be controlled under the load varied.
Effects of end- on oriented polymer chains at the donor/ acceptor interface in organic solar cells
(2018-12-07)
Wang, Fanji
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Nakano, Kyohei
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Yoshida, Hiroyuki
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Hashimoto, Kazuhito
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Segawa, Hiroshi
Molecular alignment at the interface between the electron donor and acceptor (D/A) materials in thin films may have a large effect on the charge generation process in organic solar cells (OSCs). In this study, the effects of the polymer chain orientations at the D/A interface were investigated in OSCs with planar heterojunction (PHJ) structures. Poly(3-alkylthiophene) films with edge-on (main chain parallel to the interface) and end-on (main chain vertical to the interface) orientations at the surface were used to construct PHJs with a fullerene derivative. Ultraviolet photoelectron spectroscopy and low-energy inverse photoelectron spectroscopy revealed that the difference in polarization energy through the charge-permanent quadrupole interaction causes a rigid energy shift of 0.5eV between the two orientations. The PHJ device with the end-on oriented polymer chains at the D/A interface showed a smaller photovoltage loss expected from the energy structure and a more efficient charge separation than the device with the edge-on oriented polymer chains. These improvements were attributed to charge delocalization along the end-on oriented polymer chains normal to the D/A interface, through which the effective binding energy of the charge pairs in the interfacial charge-transfer state was reduced. These results provide important information about molecular arrangements at the D/A interface that may enable further improvements in OSC performance.
Temperature-Controlled Thiation of alpha-Cyano-beta-Alkynyl Carbonyl Derivatives for De Novo Synthesis of 2-Aminothiophenes and Thieno[2,3-c]isothiazoles
(2018-12-07)
Kao, Tzu-Ting
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Peng, Bo-Kai
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Liang, Min-Chieh
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Lee, Chia-Jui
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Chen, I-Chia
Making use of temperature-controlled thiation as a key operation, a simple route to 2-aminothiophenes or thieno[2,3-c]isothiazoles has been newly developed wherein the 2-aminothiophene nucleus was formed through an initial formation of thioamide followed by a 5-exo-dig addition to the tethered alkyne; however, under harsher thermal conditions, excess sulfur-transferring reagents enabled further oxidative thiation to generate the corresponding thieno[2,3-c]isothiazoles.
李孟穎　甜點照亮的新人生
(2018-12-09)
李沛榆
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Department of Communication and Technology
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傳播與科技學系
從辦公室白領到開設甜點店，「創業」讓李孟穎的人生更精彩。
黃牛猖獗　演唱會搶票大作戰
(2018-12-09)
許可晴
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Department of Communication and Technology
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傳播與科技學系
每當有知名歌手開演唱會時，黃牛票的議題一定會被拿出來討論，究竟為何在演唱會的領域，黃牛票問題會這麼難解決呢？
閉目不只養神　還能養創意？
(2018-12-09)
郭玟妤
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Department of Communication and Technology
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傳播與科技學系
遇到百思不得其解的難題，若不是問題太深奧，或許是時候換個「方式」思考了。
蔡佳璇　特效化妝之路
(2018-12-09)
林芷懷
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Department of Communication and Technology
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傳播與科技學系
在特效化妝師蔡佳璇細膩的妝點下，無論駭人的屍體或是精緻的妝容都栩栩如生。
305期總編輯的話
(2018-12-09)
吳佳璘
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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305期，總計10篇文章。本期頭題為郭玟妤的〈閉目不只養神還能養創意？〉，揭開科技新知的寫作新紀元，全文筆調輕鬆不生硬！本期輪播小巧思，請點開總編輯的話。
完美的弧度
(2018-12-09)
許家芸
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Department of Communication and Technology
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傳播與科技學系
什麼才是人生中最完美的弧度？不用想太多，就笑一下吧！希望這首歌可以溫暖低落、不開心的你們，我永遠會在你們身邊，我的朋友。
照亮女孩的魔髮師　Ann
(2018-12-09)
黃齡萱
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Department of Communication and Technology
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傳播與科技學系
「我覺得髮型設計師是客人的光。」Ann一邊幫客人上髮捲，一邊說著，對她來說幫客人變漂亮就像給他們光一樣，照亮他們，帶領他們自信地面對人群。
廣設直飲台　生飲自來水？
(2018-12-09)
王允妍
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Department of Communication and Technology
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傳播與科技學系
台北自來水事業處在台北地區多處設置直飲台，讓民眾生飲自來水。但究竟台灣的自來水能不能喝？
媽媽的好滋味　越式涼拌粄條
(2018-12-09)
顏筱娟
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Department of Communication and Technology
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傳播與科技學系
媽媽在越南成長，遠嫁他鄉來到台灣。每當她懷念家鄉時，解鄉愁的其中一個辦法就是烹煮家鄉食物。越式涼拌粄條更是她常烹煮料理之一，輕鬆就能品嘗家鄉味。
張育榕　打造寵物友善城市
(2018-12-09)
黃俊軒
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Department of Communication and Technology
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傳播與科技學系
「你領養，我送畫」是張育榕近幾年幫助流浪狗所舉辦的活動，為什麼她要做一件沒有金錢回報的事呢？
外公的那點事兒
(2018-12-09)
梁書瑜
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Department of Communication and Technology
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傳播與科技學系
外公是一名退伍軍人，說話充滿朝氣、走路健步如飛，但在他那雙鷹眼底下，總流露著一股淡淡的孤獨。