Langage 연구 ( 1 ) - 현상학적 조망

정윤희 ( Yun Hi Chung ) 한국불어불문학회 1995 불어불문학연구 Vol.30 No.2

Cette e´tude est une approche phe´nome´nologique pour rechercher l`essence du langage humain. Etant donne´ que le langage est une structure complexe construite des e´le´ments physique, organique, physiologique et psychique, et que tout cela est au plan psychique sauf le son qui participe a` la parole du sujet parlant, l`observation sur son psychisme devrait pre´ce´der tout d`abord. Parmi les me´thodes qui sont consacre´es aux e´tudes du langage, la plus remarquable sera peut-e^tre celle par la phe´nome´nologie. La phe´nome´nologie, qui est un base des descriptions de toutes les sicences, est conside´re´e comme un principe pre´sentant a` priori la relation entre le monde existant et l`esprit humain. Par la`, cette e´tude vise, au point de vue phe´nome´nologique, a` rechercher la nature de la langue et de sa parole ou discours en suivant les ope´rations de la pense´e, c`est a` dire en poursuivant les activite´s de l`esprit du sujet parlant. Et puis, on va ajouter, comme un bon mode`le de la the´orie du langage, un bref analyse du psycho-me´canisme de Gustave Guillaume. Si on re´sume, en bref, la conclusion de cette e´tude, on peut dire que le langage est le monde exte´rieur transforme´ en possibilite´s par les activite´s de la conscience, c`est a` dire par la perception du sujet parlant. Ces possibilite´s sont fixe´s dans la conscience en deux formes de repre´sentations ou phe´nome`nes: repre´sentations spatiale-ide´es des e^tres et des choses-, et temporelle-ide´es des actes ou des mouvements. Alors, on peut bien dire aussi que le monde exte´rieur ou les expe´riences du sujet parlant peuvent e^tre traduits par le langage. c`est a` dire que le langage est un seul instrument pour l`interpre´tation du monde objective´ par le conscience du sujet parlant.

Novel triethylsilylethynyl anthracene-based organic semiconductors for high performance field effect transistors

Yun, Hui-Jun,Chung, Dae Sung,Kang, Il,Park, Jong Won,Kim, Yun-Hi,Kwon, Soon-Ki The Royal Society of Chemistry 2012 Journal of materials chemistry Vol.22 No.47

<P>A series of triethylsilylethynyl anthracene (TESAN) derivatives, end-capped with bithiophene and thienothiophene, were synthesized by Suzuki coupling. The thermal, optical, electrochemical, and crystalline properties of the TESAN derivatives were reported and correlated with charge transport behavior measured <I>via</I> both a thin film transistor and a single crystal transistor. The TESAN derivative substituted with bithiophene exhibited more efficient π electron delocalization over the molecule compared to the derivative substituted with fused thienothiophene, and consequently gave the highest FET mobility, 1.28 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>, from single crystal transistors with negligible hysteresis and almost zero turn-on voltage. The discrepancy of charge carrier mobility between the thin film transistor and single crystal transistor and the solvent annealing effects are discussed in conjunction with morphological and structural analyses.</P> <P>Graphic Abstract</P><P>A series of triethylsilylethynyl anthracenes, end-capped with bithiophene and thienothiophene, are synthesized and used as semiconductors for high mobility transistors. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2jm34160c'> </P>

綠膿菌의 Pyocine Ⅰ型의 亞型分類에 關한 硏究

尹熙雄,鄭在奎 中央醫學社 1972 中央醫學 Vol.23 No.2

As Pyocine type I of P seudonas aruginosa by the method of Giliies and Govan occupies a majority of strains typed, subtyping of Type I is necessary to increase the significance of pyocine typing in the epidemiology of Pseudomonas aeruginosa infections. The author tried to type I strains isolated from various wound infections (general strain) and viginal cavities (vaginal strains) into subgroups. Strains used as indicator are 74 untypable strains of stock cultures. Among indicators used, 37 strains were considered of no value since they were completely inhibited or resistant to all pyocine-producine strains. Among rest of 37 indicators, 9 strains were resistant to all vaginal producer strains but inhibited by some general strains, and 4 strains were on the contrary inhibited by all vaginal strains but resistant to some general strains. The rest of 24 strains exhibited various patterns by producer strains. From 24 indicators, 5 strains were selected to formulate a subtyping pattern. With the formula general strains and vaginal strains can be subtyped, but still exhibited a significant differences between both groups in subtyped pyocine patterns.

Morphology-Driven High-Performance Polymeric Photodetector

Chung, Dae Sung,Rho, Yecheol,Ree, Moonhor,Kwon, Soon-Ki,Kim, Yun-Hi American Chemical Society 2012 ACS APPLIED MATERIALS & INTERFACES Vol.4 No.9

<P>The influence of polymer/fullerene morphology on photodetector performance is reported. Various morphologies of spin-coated films are generated by different blending ratio. Morphological study combined with measurement of charge carrier mobility reveals that blend films with an excess content of crystalline fullerene have a phase-separated morphology, resulting in enhanced charge carrier mobility. Under this phase separated morphology, photovoltaic performance is enhanced because of the generation of percolating pathways for charge carriers. Interestingly, however, a homogeneous morphology is found to be more beneficial for photodetector application than this phase separated morphology. An optimized device displayed 3 dB bandwidth up to 1 kHz and detectivities up to <I>D</I> = 1.1 × 10<SUP>10</SUP> cm Hz<SUP>1/2</SUP> W<SUP>–1</SUP>. These results emphasize the importance of developing an independent strategy for designing high performance photodetectors separately from solar cell devices both in terms of materials and device geometry. Possible relations between morphology and various figures of merit of photodetectors are discussed.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2012/aamick.2012.4.issue-9/am301128d/production/images/medium/am-2012-01128d_0007.gif'></P>

Charge transport characteristics of a high-mobility diketopyrrolopyrrole-based polymer

Chung, Dae Sung,Kang, Il,Kim, Yun-Hi,Kwon, Soon-Ki The Royal Society of Chemistry 2013 Physical chemistry chemical physics Vol.15 No.35

<P>In this study, we attempt to unveil the charge-transport abnormality of the widely studied diketopyrrolopyrrole (DPP)-based polymers with exceptionally high charge carrier mobility [>5 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>]. Based on the electric field and temperature dependence of the charge-transport characteristics of the field effect transistor (FET) geometry of one of the highly conductive DPP derivatives, namely, (poly[2,5-bis(7-decylnonadecyl)pyrrolo[3,4-<I>c</I>]pyrrole-1,4(2<I>H</I>,5<I>H</I>)-dione-(<I>E</I>)-(1,2-bis(5-(thiophen-2-yl)selenophen-2-yl)ethene) (PDPPDTSE), we show that the high gate–source bias drew the carriers closer to the interface of the semiconductor/dielectric layers where the density of state (DOS) of the charge carrier is significantly broader than the bulk. We argue that the intrinsically narrow DOS in the PDPPDTSE bulk resulted in significantly different charge-transport behavior between the semiconductor bulk and the semiconductor/dielectric interface, which was not visible in the other low-mobility organic semiconductors that contain intrinsically high density of trap states in their bulk. To avoid these charge transport abnormalities, we try to operate the FETs under low gate bias without compromising the accumulated charge carrier density. By carefully employing a thin metal oxide covered with a self-assembled monolayer (SAM) as a dielectric layer, we can demonstrate low-voltage PDPPDTSE FETs with near-ideal performance both in terms of hysteresis-free operation and operating reliability while maintaining a high charge carrier mobility of ∼2.8 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>.</P> <P>Graphic Abstract</P><P>In this study, we attempt to unveil the charge-transport abnormality of DPP-based polymers with exceptionally high charge carrier mobility. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cp52422a'> </P>

Synthesis of a Low-Bandgap Fluorinated Donor–Acceptor Copolymer and Its Optoelectronic Application

Yun, Hui-Jun,Hwang, Moon Chan,Park, So Min,Kim, Ran,Chung, Dae Sung,Kim, Yun-Hi,Kwon, Soon-Ki American Chemical Society 2013 ACS APPLIED MATERIALS & INTERFACES Vol.5 No.13

<P>We demonstrate the synthesis of a new copolymer which is composed of dialkyl thienylated benzodithiophene and perfluororalkyl-carbonyl thienothiophene (DTBDT-TTFO) and the characterization of its optoelectronic properties. The introduction of thienyl groups enabled the extended delocalization of π electrons in the DTBDT-TTFO backbone and efficient intermolecular charge transport as proved by the fairly high field effect mobility of 0.02 cm<SUP>2</SUP>/(V s). The introduction of perfluororalkyl-carbonyl side chains resulted in a significant red-shift of DTBDT-TTFO in the absorption spectra and a decrease in the HOMO and LUMO levels. The resulting energy levels of DTBDT-TTFO were not satisfactory for solar cell applications, especially in terms of charge separation at the polymer/PCBM interfaces. Rather, the DTBDT-TTFO showed better energy level matching with the colloidal nanocrystals (NCs) of CdSe. A photodetector based on the bulkheterojunction of DTBDT-TTFO and CdSe NCs with coplanar device geometry resulted in a high photoconductive gain (responsivity higher than 1A/W under a low operating voltage of 1 V), possibly arising from electron trapping at CdSe NCs such that the hole can travel along the detector and its surrounding circuit. More importantly, the photodetector revealed a time constant of a few hundreds of microseconds, which means that the response speed of the photodetector is fast enough for lag-free imaging applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2013/aamick.2013.5.issue-13/am4007935/production/images/medium/am-2013-007935_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am4007935'>ACS Electronic Supporting Info</A></P>

Solution-Processed Organic Photovoltaic Cells with Anthracene Derivatives

Chung, Dae Sung,Park, Jong Won,Yun, Won Min,Cha, Hyojung,Kim, Yun-Hi,Kwon, Soon-Ki,Park, Chan Eon Wiley (John WileySons) 2010 ChemSusChem Vol.3 No.6

<P>Solution-processed small-molecule bulk heterojunction photovoltaic cells are fabricated by using [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM) as electron acceptor and triisopropylsilylethynyl anthracene (TIPSAnt) derivatives substituted with naphthalene (TIPSAntNa) and bithiophene (TIPSAntBT) as electron donors. In contrast to TIPS-pentacene, the TIPSAnt derivatives are not susceptible to Diels-Alder reactions with PCBM when processed in solution, as confirmed by UV/Vis measurements. Photoluminescence quenching measurements show exciton diffusion lengths of 5 and 3 nm for TIPSAntBT and TIPSAntNa, respectively. Blending TIPSAntBT and TIPSAntNa with PCBM (1:1, 1:2, 1:3, and 1:4 weight ratios) produces films that possess adequate hole and electron mobilities. The morphological changes that result from varying the blending ratio range from obvious phase-segregated crystalline domains at a 1:1 ratio to homogeneous, nearly amorphous phases at a 1:4 ratio. Bulk heterojunction solar cells prepared by using a TIPSAntBT:PCBM blend reach power conversion efficiencies as high as 1.4 %.</P>

Flexible High‐Performance All‐Inkjet‐Printed Inverters: Organo‐Compatible and Stable Interface Engineering

Chung, Seungjun,Jang, Mi,Ji, Seon‐,Beom,Im, Hwarim,Seong, Narkhyeon,Ha, Jewook,Kwon, Soon‐,Ki,Kim, Yun‐,Hi,Yang, Hoichang,Hong, Yongtaek WILEY‐VCH Verlag 2013 ADVANCED MATERIALS Vol.25 No.34

<P><B>High‐performance all‐inkjet‐printed organic inverters</B> are fabricated on flexible substrates. By introducing end‐functionalized polystyrene on both surfaces of inkjet‐printed source/drain Ag electrodes and poly(4‐vinylphenol) dielectrics, organic‐compatible and hydroxyl‐free interfaces between those layers and 6,13‐bis(triisopropylsilylethynyl)pentacene drastically reduce the interfacial trap and contact resistance. The resulting organic inverters show a full up‐down switching performance and a high voltage gain of 19.8.</P>

Comparative Studies on the Relations between Composition Ratio and Charge Transport of Diketopyrrolopyrrole-Based Random Copolymers

Yun, Hui-Jun,Cho, Jangwhan,Chung, Dae Sung,Kim, Yun-Hi,Kwon, Soon-Ki American Chemical Society 2014 Macromolecules Vol.47 No.20

<P>Random copolymerization strategy is introduced to increase the solubility of donor–acceptor copolymers so that they can be processed with environmentally benign, halogen-free solvents. Traditionally, it has been believed that the random copolymer with a lower crystalline order should have a significantly lower charge carrier mobility. This report shows that random copolymerization between two highly planar, charge-delocalized repeating units can significantly enhance the solubility while almost preserving the high charge carrier mobility. A comparative study was conducted for a series of random copolymers consisting of diketopyrrolopyrrole–thienothiophene (DPP-TT) and DPP–selenophene–vinylene–selenophene (DPP-SVS) with composition ratios of 10:0, 9:1, 7:3, 5:5, 3:7, 1:9, and 0:10 by using the crystalline order determined from grazing-incident X-ray diffraction measurements and charge carrier mobility determined from field effect transistor measurements. The results showed that the copolymer tends to have a lower degree of intermolecular ordering as the DPP-TT:DPP-SVS composition ratio approaches 5:5 because of the increased segmental randomness in the polymer chain. Nevertheless, the FET mobility did not follow the tendency of crystalline order; instead, it simply followed the order of increasing content of DPP-SVS in the copolymer. This result implies that we can use the random copolymerization strategy to increase the solubility of donor–acceptor copolymers if the two constituent repeating units are structurally planar and the electrons are fully delocalized.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/mamobx/2014/mamobx.2014.47.issue-20/ma501980m/production/images/medium/ma-2014-01980m_0003.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ma501980m'>ACS Electronic Supporting Info</A></P>

High Performance Organic Nonvolatile Flash Memory Transistors with High-Resolution Reduced Graphene Oxide Patterns as a Floating Gate

Chung, Dae Sung,Lee, Sung Min,Back, Jang Yeol,Kwon, Soon-Ki,Kim, Yun-Hi,Chang, Suk Tai American Chemical Society 2014 ACS APPLIED MATERIALS & INTERFACES Vol.6 No.12

<P>High-performance organic nonvolatile memory transistors (ONVMTs) are demonstrated, the construction of which is based on novel integration of a highly conductive polymer as a semiconductor layer, hydroxyl-free polymer as a tunneling dielectric layer, and high-resolution reduced graphene oxide (rGO) patterns as a floating gate. Finely patterned rGO, with a line width of 20–120 μm, was embedded between SiO<SUB>2</SUB> and the polymer dielectric layer, which functions as a nearly isolated charge-trapping center. The resulting ONVMTs demonstrated ideal memory behavior, and the transfer characteristics promptly responded to writing and erasing the gate bias. In particular, the retention time of written/erased states tended to increase as the rGO line width was reduced, implying that the line width is a critical factor in suppressing charge release from rGO. Using a 20-μm-wide rGO pattern, a nonvolatile large memory window (>20 V) was retained for more than 5 × 10<SUP>5</SUP> s, which is 50 times longer than non-patterned rGO films.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2014/aamick.2014.6.issue-12/am501909v/production/images/medium/am-2014-01909v_0007.gif'></P>