http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Synthesis of methoxybenzoflavones and assignments of their NMR data
Hwang, Doseok,Jo, Geunhyeong,Hyun, Jiye,Lee, Sung Dae,Koh, Dongsoo,Lim, Yoongho John Wiley Sons, Ltd 2012 Magnetic resonance in chemistry Vol.50 No.1
<P>A phytotoxic root exudate from <I>Acroptilon repens</I> was identified as 7,8‐benzoflavone, an inhibitor of cytochrome P450 1A2 and activator of cytochrome P450 3A4. The synthetic 5,6‐benzoflavone also is a potent phytotoxin. Six 7,8‐benzoflavones and eight 5,6‐benzoflavones were synthesized in this study. The NMR data for a few of these compounds have been previously reported; however, the NMR data for most of them have not been reported. For reference purposes, the complete NMR data for the 14 benzoflavones are described. Copyright © 2012 John Wiley & Sons, Ltd.</P>
A Peptide Produced by Pseudomonas tolaasi, Tolaasin Binds to Metal Ions
Geunhyeong Jo,Doseok Hwang,Yoonkyung Woo,Younggiu Lee,Yeonjoong Yong,강경래,Jiye Hyun,Young-Kee Kim,Dong-Woon Kim,Yoongho Lim 한국응용생명화학회 2011 Applied Biological Chemistry (Appl Biol Chem) Vol.54 No.4
Brown blotch disease in mushrooms is caused by Pseudomonas tolaasin, which produces a peptide toxin, tolaasin I, and zinc ion inhibits the channel formed by tolaasin I. NMR experiments revealed that zinc, sodium, and calcium ions can bind to tolaasin I and their binding position on tolaasin I is the lactone ring.
Sung, Woongmo,Wang, Wenjie,Lee, Jonggwan,Vaknin, David,Kim, Doseok American Chemical Society 2015 The Journal of Physical Chemistry Part C Vol.119 No.13
<P>We report on halide ion (Cl<SUP>–</SUP>, Br<SUP>–</SUP>, I<SUP>–</SUP>) adsorption from the subphase water to a cationic Langmuir monolayer consisting of 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP) molecules at the air/water interface. Reductions in the water OH signal of sum-frequency spectra and the surface pressure of the π–<I>A</I> isotherm follow the order of the anion size, indicating preferable adsorption of the larger anions to better screen the surface charge of the DPTAP monolayer. Complementary X-ray fluorescence measurements of DPTAP on Cl<SUP>–</SUP> and I<SUP>–</SUP> reveal that the integrated number of adsorbed ions within the probing depth (6–8 nm) is the same for both ions. Incorporating the above outcomes leads to the contrasting adsorption structures that the larger halide anions (I<SUP>–</SUP>) are directly adsorbed to the headgroup strata, while the Cl<SUP>–</SUP> ions form a more diffusive distribution contiguous to the monolayer. Our study shows that the length scale over which ions neutralize a charged interface varies significantly and specifically even for monovalent ions.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2015/jpccck.2015.119.issue-13/jp512233g/production/images/medium/jp-2014-12233g_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp512233g'>ACS Electronic Supporting Info</A></P>
Fluorescence characteristics of isolated dye molecules within silicalite-1 channels.
Shim, Tae Kyu,Lee, Myoung Hee,Kim, Doseok,Kim, Hyun Sung,Yoon, Kyung Byung Plenum Press ; Springer 2012 JOURNAL OF FLUORESCENCE Vol.22 No.6
<P>Fluorescence characteristics of hemicyanine dye molecules isolated from neighboring molecules and strongly restricted inside nanosized pores of zeolite (silicalite-1) crystal were investigated. For samples in which the molecules were sufficiently far away from the others, the fluorescence decay lifetime of the molecules was about 2.2 ns. As the intermolecular distance was reduced, the steady-state fluorescence peak shifted toward the longer wavelength and the fluorescence efficiency decreased markedly. The fluorescence decay lifetime also decreased to 0.8 ns for a sample with the smallest intermolecular distance of 2.1 nm. These results were explained in terms of a dipole-dipole interaction between pairs of dye molecules. From the relation between the intermolecular distances and the fluorescence decay lifetimes of the molecules, the radius of energy transfer of hemicyanine donor-acceptor pair in zeolite matrix was determined to be 2.2 nm, in fair agreement with the calculated F?rster radius between dye molecules of the same species.</P>
Origin of the Instability of Octadecylamine Langmuir Monolayer at Low pH
Avazbaeva, Zaure,Sung, Woongmo,Lee, Jonggwan,Phan, Minh Dinh,Shin, Kwanwoo,Vaknin, David,Kim, Doseok American Chemical Society 2015 Langmuir Vol.31 No.51
<P>It has been reported that an octadecylamine (ODA) Langmuir monolayer becomes unstable at low pH values with no measurable surface pressure at around pH 3.5, suggesting significant dissolution of the ODA molecule into the subphase solution (Albrecht, <I>Colloids Surf. A</I> <B>2006</B>, <I>284–285</I>, 166–174). However, by lowering the pH further, ODA molecules reoccupy the surface, and a full monolayer is recovered at pH 2.5. Using surface sum-frequency spectroscopy and pressure–area isotherms, it is found that the recovered monolayer at very low pH has a larger area per molecule with many gauche defects in the ODA molecules as compared to that at high pH values. This structural change suggests that the reappearance of the monolayer is due to the adsorbed Cl<SUP>–</SUP> counterions to the protonated amine groups, leading to partial charge neutralization. This proposition is confirmed by intentionally adding monovalent salts (i.e., NaCl, NaBr, or NaI) to the subphase to recover the monolayer at pH 3.5, in which the detailed structure of the monolayer is confirmed by sum frequency spectra and the adsorbed anions by X-ray reflectivity.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2015/langd5.2015.31.issue-51/acs.langmuir.5b03947/production/images/medium/la-2015-039476_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/la5b03947'>ACS Electronic Supporting Info</A></P>
정인기,홍도석,이영태 한국항공대학교 경영연구소 1998 경영연구 Vol.5 No.1
This paper examined that why CT-2 service have failed to succeed in the wireless market and how to make it resurrect to save huge sunk cost and create social welfare. First we summarized the status of CT-2 service market and then examined why CT-2 service had failed to meet users needs in the market. And we examined the potential of CT-2 service and then we suggested marketing strategy of CT-2 service to minimize financial risk and to maximize users benefit, that is: how to activate CT-2 service with a minimum additional input. Finally we tried to offer prospect of wireless services and to position CT-2 service to the right place on the strategic map.
Chae, Soo Sang,Min, Haesik,Lee, Jeong Hun,Hwang, Byounghar,Sung, Woong Mo,Jang, Woo Soon,Yoo, Young Bum,Oh, Jinyoung,Park, Jee Ho,Kang, Daeseung,Kim, Doseok,Kim, Youn Sang,Baik, Hong Koo WILEY‐VCH Verlag 2013 ADVANCED MATERIALS Vol.25 No.10
<P><B>A compartmentalized multidomain alignment state</B> of a layer of liquid crystal display is achieved using an ultrathin, highly transparent, and ultrafast‐responsive alignment layer fabricated by a simple method. The ultrathin alignment layer consists of a self‐assembled oligomer layer of poly(dimethylsiloxane) (PDMS) formed by utilizing the oligomers that diffuse out from a PDMS elastomer stamp during a contact printing process.</P>
Jo, Geunhyeong,Hyun, Jiye,Hwang, Doseok,Lee, Young Han,Koh, Dongsoo,Lim, Yoongho John Wiley Sons, Ltd. 2011 Magnetic resonance in chemistry Vol.49 No.6
<P><B>Abstract</B></P><P>Resveratrol is a polyphenol isolated from many natural sources including grapes, mulberries, eucalyptus, spruce, lilies, and peanuts. The hydroxyl groups in polyphenols can be substituted with various functional groups, allowing production of multiple derivatives. NMR spectroscopy is used to identify new derivatives. Since the complete NMR data of the known derivatives can be useful for identification of the newly isolated derivatives, here, we report the synthesis of 14 methoxylated stilbenes and four 1,2‐diphenylethanes and their NMR data. Copyright © 2011 John Wiley & Sons, Ltd.</P>