Browsing by Issue Date, starting with "2016-10-28"

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Quantitative mass spectrometry: an overview
(2016-10-28)
Urban, Pawel L.
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應用化學系
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Department of Applied Chemistry
Mass spectrometry (MS) is a mainstream chemical analysis technique in the twenty-first century. It has contributed to numerous discoveries in chemistry, physics and biochemistry. Hundreds of research laboratories scattered all over the world use MS every day to investigate fundamental phenomena on the molecular level. MS is also widely used by industry-especially in drug discovery, quality control and food safety protocols. In some cases, mass spectrometers are indispensable and irreplaceable by any other metrological tools. The uniqueness of MS is due to the fact that it enables direct identification of molecules based on the mass-to-charge ratios as well as fragmentation patterns. Thus, for several decades now, MS has been used in qualitative chemical analysis. To address the pressing need for quantitative molecular measurements, a number of laboratories focused on technological and methodological improvements that could render MS a fully quantitative metrological platform. In this theme issue, the experts working for some of those laboratories share their knowledge and enthusiasm about quantitative MS. I hope this theme issue will benefit readers, and foster fundamental and applied research based on quantitative MS measurements. This article is part of the themed issue \'Quantitative mass spectrometry\'.
Infrared spectra of two isomers of protonated carbonyl sulfide (HOCS+ and HSCO+) and t-HOCS in solid Para-hydrogen
(2016-10-28)
Tsuge, Masashi
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Lee, Yuan-Pern
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應用化學系
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應用化學系分子科學碩博班
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Department of Applied Chemistry
We report infrared (IR) spectra of HOCS+, HSCO+, t-HOCS, and other species produced on electron bombardment of a mixture of carbonyl sulfide (OCS) and para-hydrogen (p-H-2) during deposition at 3.2 K. After maintenance of the matrix in darkness for 15 h, the intensities of absorption features of HOCS+ at 2945.9 (nu(1)), 1875.3 (nu(2)), and 1041.9 (nu(3)) cm(-1) and those of HSCO+ at 2506.9 (nu(1)) and 2074.2 (nu(2)) cm(-1) decreased through neutralization with trapped electrons. Lines observed at 3563.4, 1394.8, and 1199.0 cm(-1), which decreased slightly in intensity after maintenance in darkness and were nearly depleted after irradiation at 373 nm, are assigned to a t-HOCS radical. The corresponding spectra of their C-13- and D-isotopologues were observed. The IR spectra of HSCO+ and t-HOCS and those of modes nu(2) and nu(3) of HOCS+ are new. The assignments were made according to the expected chemical behavior and a comparison of experimental and calculated wavenumbers and C-13- and D-isotopic shifts. The wavenumber of the OH stretching mode (2945.9 cm(-1)) of HOCS+ in solid p-H-2 is significantly red-shifted from that (3435.16 cm(-1)) reported for gaseous HOCS+; this shift is attributed to partial sharing of a proton between OCS and H-2. The corresponding p-H-2 induced shift is small in HSCO+ because of a much weaker interaction between HSCO+ and H-2. Published by AIP Publishing.
Quantitative mass spectrometry of unconventional human biological matrices
(2016-10-28)
Dutkiewicz, Ewelina P.
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Urban, Pawel L.
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應用化學系
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應用化學系分子科學碩博班
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Department of Applied Chemistry
The development of sensitive and versatile mass spectrometric methodology has fuelled interest in the analysis of metabolites and drugs in unconventional biological specimens. Here, we discuss the analysis of eight human matrices-hair, nail, breath, saliva, tears, meibum, nasal mucus and skin excretions (including sweat)-by mass spectrometry (MS). The use of such specimens brings a number of advantages, the most important being non-invasive sampling, the limited risk of adulteration and the ability to obtain information that complements blood and urine tests. The most often studied matrices are hair, breath and saliva. This review primarily focuses on endogenous (e.g. potential biomarkers, hormones) and exogenous (e.g. drugs, environmental contaminants) small molecules. The majority of analytical methods used chromatographic separation prior to MS; however, such a hyphenated methodology greatly limits analytical throughput. On the other hand, the mass spectrometric methods that exclude chromatographic separation are fast but suffer from matrix interferences. To enable development of quantitative assays for unconventional matrices, it is desirable to standardize the protocols for the analysis of each specimen and create appropriate certified reference materials. Overcoming these challenges will make analysis of unconventional human biological matrices more common in a clinical setting. This article is part of the themed issue \'Quantitative mass spectrometry\'.
Orientation hydrogen-bonding effect on vibronic spectra of isoquinoline in water solvent: Franck-Condon simulation and interpretation
(2016-10-28)
Liu, Yu-Hui
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Wang, Shi-Ming
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Wang, Chen-Wen
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Zhu, Chaoyuan
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Han, Ke-Li
The excited-state orientation hydrogen-bonding dynamics, and vibronic spectra of isoquinoline (IQ) and its cationic form IQc in water have been investigated at the time-dependent density functional theory quantum chemistry level plus Franck-Condon simulation and interpretation. The excited-state orientation hydrogen bond strengthening has been found in IQ: H2O complex due to the charge redistribution upon excitation; this is interpreted by simulated 1: 1 mixed absorption spectra of free IQ and IQ: H2O complex having best agreement with experimental results. Conversely, the orientation hydrogen bond in IQc: H2O complex would be strongly weakening in the S-1 state and this is interpreted by simulated absorption spectra of free IQc having best agreement with experimental results. By performing Franck-Condon simulation, it reveals that several important vibrational normal modes with frequencies about 1250 cm(-1) involving the wagging motion of the hydrogen atoms are very sensitive to the formation of the orientation hydrogen bond for the IQ/IQc:H2O complex and this is confirmed by damped Franck-Condon simulation with free IQ/IQc in water. However, the emission spectra of the IQ and IQc in water have been found differently. Upon the excitation, the simulated fluorescence of IQ in water is dominated by the IQ: H2O complex; thus hydrogen bond between IQ and H2O is much easier to form in the S-1 state. While the weakened hydrogen bond in IQc: H2O complex is probably cleaved upon the laser pulse because the simulated emission spectrum of the free IQc is in better agreement with the experimental results. Published by AIP Publishing.
Revisiting the quantitative features of surface-assisted laser desorption/ionization mass spectrometric analysis
(2016-10-28)
Wu, Ching-Yi
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Lee, Kai-Chieh
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Kuo, Yen-Ling
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Chen, Yu-Chie
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應用化學系
Surface-assisted laser desorption/ionization (SALDI) coupled with mass spectrometry (MS) is frequently used to analyse small organics owing to its clean background. Inorganic materials can be used as energy absorbers and the transfer medium to facilitate the desorption/ionization of analytes; thus, they are used as SALDI-assisting materials. Many studies have demonstrated the usefulness of SALDI-MS in quantitative analysis of small organics. However, some characteristics occurring in SALDI-MS require certain attention to ensure the reliability of the quantitative analysis results. The appearance of a coffee-ring effect in SALDI sample preparation is the primary factor that can affect quantitative SALDI-MS analysis results. However, to the best of our knowledge, there are no reports relating to quantitative SALDI-MS analysis that discuss or consider this effect. In this study, the coffee-ring effect is discussed using nanoparticles and nanostructured substrates as SALDI-assisting materials to show how this effect influences SALDI-MS analysis results. Potential solutions for overcoming the existing problems are also suggested. This article is part of the themed issue \'Quantitative mass spectrometry\'.
Holographic study of the jet quenching parameter in anisotropic systems
(2016-10-28)
Wang, Luying
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Wu, Shang-Yu
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電子物理學系
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Department of Electrophysics
We first calculate the jet quenching parameter of an anisotropic plasma with a U(1) chemical potential via AdS/CFT duality. The effects of charge, anisotropy parameter, and quark motion direction on the jet quenching parameter are investigated. We then discuss the situation of an anisotropic black brane in the IR region. We study both the jet quenching parameters along the longitudinal direction and the transverse plane.
Low-temperature anomalous magnetic behavior of Co2TiO4 and Co2SnO4
(2016-10-28)
Nayak, S.
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Dasari, K.
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Joshi, D. C.
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Pramanik, P.
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Palai, R.
We report the low-temperature anomalous magnetic behavior of ferrimagnetic spinels cobalt orthotitanate (Co2TiO4), which exhibits magnetic compensation behavior across 31.74 K, and cobalt orthostannate (Co2SnO4) exhibiting two sequential magnetic transitions, namely (i) ferrimagnetic to paramagnetic transition with Neel temperature T-N similar to 41 K and reentrant spin-glass behavior with glass transition temperature T-SG similar to 39 K. The Arrott plot (H/M versus M-2) criterion has been used to extricate the order of sequential magnetic transitions occurring below TN. Negative slopes of the Arrott plots below 32 K, metamagnetic-like character of the M-H isotherms, anomalies in the specific-heat (C-P T-1 versus T) below 15 K, and a zero-crossover of isothermal magnetic-entropychange (Delta S) signify the presence of pseudo first-order discontinuous magnetic phase transition in the low-temperature regime 5K <= T <= 32 K. The dc- and ac-susceptibilities of both Co2TiO4 and Co2SnO4 are interpreted in terms of frozen-spin-clusters, which are responsible for very large magnitudes of the coercivity H-C similar to 20 kOe and bipolar-exchange bias H-EB similar to -20 kOe observed below 10 K. Published by AIP Publishing.
跨時代運輸　智能高速公路
(2016-10-30)
曾婕茵
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Department of Communication and Technology
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傳播與科技學系
韓國自從1990年代開始導入智慧型運輸系統（ITS，Intelligent Transport Systems）的概念，近20年來致力於相關技術的研究與交通建設的革新，本文透過韓國智能高速公路的建設與規劃，探究智慧型運輸在韓國的應用與未來發展。
高雄電影節　電影人齊聚
(2016-10-30)
黃佳俐
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Department of Communication and Technology
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傳播與科技學系
2016年10月21日至11月6日，為期半個月的高雄電影節，10月21日在高雄市立圖書館總館舉辦開幕典禮，電影工作者和影迷齊聚一堂。
我的喀報體驗記
(2016-10-30)
吳偉立
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Department of Communication and Technology
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傳播與科技學系
第一次打喀報，請大家多多指教。
相反的世界　不顛倒是非
(2016-10-30)
彭書耘
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Department of Communication and Technology
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傳播與科技學系
帕蒂瑪的顛倒世界，講述男女主角在重力相異的情況下，攜手突破難關，找尋真相。藉由此片探討反烏托邦主義及人性議題。
明日科技曙光　台灣光子源
(2016-10-30)
何肇耕
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Department of Communication and Technology
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傳播與科技學系
從原理、技術、產業應用等面向初步介紹台灣光子源。
滾吧　這世界
(2016-10-30)
林宥成
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Department of Communication and Technology
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傳播與科技學系
藉由身邊發生的事情，傳達滿滿負能量。
海洋野餐日　輕食漫步去
(2016-10-30)
鄭懿君
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Department of Communication and Technology
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傳播與科技學系
十月22日由TLC舉辦的「TLC海洋野餐日」，除了有精彩的樂團演出，民眾也能逛市集，並在野餐的同時享受愜意的午後時光。
家
(2016-10-30)
魏若芸
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Department of Communication and Technology
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傳播與科技學系
當愛情萌芽，家成為兩人分享彼此生活的地方。但維繫戀情並不容易，很多時候熱情褪去，感情也來到尾聲。
小丑嘉年華　散播愛與歡樂
(2016-10-30)
郭宜婷
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王韋翔
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Department of Communication and Technology
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傳播與科技學系
台灣首屆國際小丑文創節，推廣小丑文化並幫助弱勢。
王姿敏　走在夢想的路上
(2016-10-30)
陳奕璇
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Department of Communication and Technology
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傳播與科技學系
王姿敏的夢想是擁有一間婚紗工作室，透過種種努力，一步一步走向目標。
世界郵展　喚起舊時集郵趣
(2016-10-30)
鄧涵文
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Department of Communication and Technology
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傳播與科技學系
台北2016國際郵展於10月21日到10月26日展出，全球73個國家、超過2000框郵集參展，還有多達140個特色攤位販賣特色郵票，吸引許多集郵愛好者前來尋寶。
總編輯的話
(2016-10-30)
張芸瑄
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Department of Communication and Technology
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傳播與科技學系
喀報第兩百五十期，共二十二篇稿件，頭題為【台媒惹議　關係「泰」敏感】。本期主題多元，國際色彩濃厚。
我想那就是愛了
(2016-10-30)
王廷瑄
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Department of Communication and Technology
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傳播與科技學系
愛無能的二十自述。