• Title/Summary/Keyword: H atoms

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Measurement of Spatiotemporal Distribution for the Density of Excited Xe Atoms in the 1s5 in Accordance with Various ITO-shapes in Ac-PDP (교류형 플라즈마 평판 표시장치(AC-PDP)에서 ITO 전극 구조에 따른 Xe 여기종의 시공간 밀도 분포 연구)

  • Cho, S.H.;Hong, Y.J.;Son, C.G.;Han, Y.G.;Jeong, Y.H.;Gwon, G.C.;Hong, B.H.;Cho, G.S.;Choi, E.H.
    • Journal of the Korean Vacuum Society
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    • v.18 no.1
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    • pp.54-59
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    • 2009
  • We have measured the spatiotemporal behavior for the density of excited Xe atoms in the $1s_5$ metastable states by laser absorption spectroscopy in accordance with various shapes of ITO electrode. The maximum density of excited Xe atoms in the Is5 state in a discharge cell for fish-boned, T-shaped and squared ITO electrodes has been measured to be $3.01{\times}10^{13}\;cm^{-3}$, $2.66{\times}10^{13}\;cm^{-3}$ and $2.06{\times}10^{13}\;cm^{-3}$, respectively. Throughout this experiment, we could understand the influence of the shapes of ITO electrode of micro discharge cell on the high efficiency of AC-PDPs.

5-Arylidene-2(5H)-Furanone Derivatives: Synthesis and Structure-Activity Relationship for Cytotoxicity

  • Bang, Seong-Cheol;Kim, Yong;Yun, Mi-Young;Ahn, Byung-Zun
    • Archives of Pharmacal Research
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    • v.27 no.5
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    • pp.485-494
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    • 2004
  • Thirty-eight 5-arylidene-2(5H)-furanone derivatives possessing halo-, methoxy-, oxo-, dioxo-, and thiophenyl groups as well as anthraquinone and naphthquinone moieties were synthesized, and their cytotoxicity was evaluated against various cancer cell lines. The introduction of halogen atoms or nitro group at aromatic ring of 5-arylidene-2(5H)-furanone was shown to increase the cytotoxicity with 5-(3-nitrobenzylidene )-2(5H)-furanone (21) being the most potent. Among anthracenyl or naphthalenyl derivatives, (E)-5-[2-(1 ,4-dimethoxy-9, 10-dioxo) anthracenyl]-2(5H)-furanone (34) showed the most potent cytotoxic activity.

The Magnetic Filtering Vacuum Arc Film Deposition System and Its Applications

  • Wang, G.F.;Zhang, H.X.;Zhang, H.J.;Zhu, H.
    • Journal of the Korean Vacuum Society
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    • v.6 no.S1
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    • pp.137-140
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    • 1997
  • A cathodic arc with beam filter is employed for the deposition of metallic and hydrogen-free amorphous carbon films. A solenoid filter is used to prevent macropaticles and nonionized atoms from reaching the substrate. The detail transport characters of the filter are presented in the paper. With an optmum filter arrangement we are able to obtain a filter output of 18.4% of the total number of ions produced by the vacuum arc discharge. The deposited amorphous cabon thin film contains no hydrogen and a high fraction of $sp^3$ is determined by XPS. A dense Ti film deposited on H13 steel improves the corrosion resistance of the H13 steel and significant improvements of corrosion resistance were observed by implanting Ti, C in the film.

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Characteristics of the Multi-Hydrogen Bonded Systems: DFT Description on the Solvated Electrons

  • Xu, Jun
    • Bulletin of the Korean Chemical Society
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    • v.34 no.11
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    • pp.3265-3268
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    • 2013
  • The multi-hydrogen bonded systems with the solvated electrons are investigated at the B3LYP/6-311++$G^{**}$ basis set level. The symmetrical linear geometrical characteristic is common for the dimer systems, while for the tetramer system, the tetrahedron configuration is generated. The NBO charge analyses demonstrate that the multi-hydrogen-multi-electron (mH-ne) coupling exist in these anion systems, as is supported by the electrostatic potential and the molecular orbital analyses. The positive chemical shift value of the central hydrogen ($H_c$) and the negative chemical shift value of the terminal hydrogen ($H_t$) indicate that the $H_c$ is electronegative while the $H_t$ is electropositive, respectively. Strong coupling between two central hydrogen atoms is demonstrated by the large spin-spin coupling constants. The solvated electron donates significant contributions for the stability of these systems.

Substrate Temperature Dependence of Microcrystalline Silicon Thin Films by Combinatorial CVD Deposition

  • Kim, Yeonwon
    • Journal of the Korean institute of surface engineering
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    • v.48 no.3
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    • pp.126-130
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    • 2015
  • A high-pressure depletion method using plasma chemical vapor deposition (CVD) is often used to deposit hydrogenated microcrystalline silicon (${\mu}c-Si:H$) films of a low defect density at a high deposition rate. To understand proper deposition conditions of ${\mu}c-Si:H$ films for a high-pressure depletion method, Si films were deposited in a combinatorial way using a multi-hollow discharge plasma CVD method. In this paper the substrate temperature dependence of ${\mu}c-Si:H$ film properties are demonstrated. The higher substrate temperature brings about the higher deposition rate, and the process window of device quality ${\mu}c-Si:H$ films becomes wider until $200^{\circ}C$. This is attributed to competitive reactions between Si etching by H atoms and Si deposition.

Measurement of Changes in Work Function on MgO Protective Layer after H2-plasma Treatment (수소 Plasma 처리 후의 MgO 보호막에 대한 일함수 변화 측정)

  • Jeong, Jae-Cheon;Rhee, Seuk-Joo;Cho, Jae-Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.7
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    • pp.611-614
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    • 2007
  • The changes in the work $function({\Phi}_w)$ in the MgO protective layers after $plasma(Ar,\;H_2)$ treatment have been studied using ${\Upsilon}-focused$ ion beam $({\Upsilon}-FIB)$ system. The ${\Phi}_w$ was determined as follows: Ar-plasma $treatment({\Phi}_w=4.52eV)$, $H_2-plasma$ $treatment({\Phi}_w=5.65eV)$, and non-plasma $treatment({\Phi}_w=4.64eV)$. The results indicated that the H-plasma could not make any effective physical etching due to the small masses of hydrogen atoms and molecules while the hydration of H-plasma could grow some contaminating materials on the surface of MgO.

Oxidative Addition Reaction of Mono(aryl)cyanoplatinum(Ⅱ) Complex with Two Amino Ligands with the Dihalogens

  • Ko Jaejung;Kim Moonsik;Kim Seho;Shin Yookil
    • Bulletin of the Korean Chemical Society
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    • v.13 no.2
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    • pp.135-139
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    • 1992
  • The mono(aryl)cyanoplatinum(II) complex $[Pt(CN)(C_6H_3{CH_2NMe_2}_2-26)]$, reacts with the dihalogens to yield the mono(aryl)cyanoplatinum complexes $[PtX_2(CN)(C_6H_3{CH_2NMe_2}_2-26)]$, (X = Cl, Br, I). The structural configuration of the two halogen atoms for a square planar platinum complex was studied by 1H-NMR spectroscopy and led to a mixture of trans and cis orientation. The trans orientation was found to be more stable in energy (1.33 kcal/mol) than the cis orientation by means of Extended H ckel calculations. On the base of a combination of the analysis of $^1H-NMR$, $^{13}C-NMR spectra and computational calculations it is assumed that the intermediate consists of an initial attack in the linear transition state, leading to the $S_{N}2$ type mechanism.

Synthesis and Properties of Noel Platinum(IV) Complexes Involving Asymmetric Chiral Diamines as Carrier Ligands

  • 이은주;전무진;손윤수
    • Bulletin of the Korean Chemical Society
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    • v.20 no.11
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    • pp.1295-1298
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    • 1999
  • Novel platinum(IV) complexes with asymmetric chiral diamine ligands cis,cis,trans-A2PtCl2(X)2 (X = OH, OCOCH3, OCOC2H5, A2 =NH2CH(CH3)CH2NH(c-C6H11)(apcha), NH2CH(CH3)CH2NH(c-C5H9)(apcpa)) have been prepared. One of the platinum(IV) complexes, (apcpa)PtCl2(OCOC2H5)2(6), was subjected to X-ray crystallographic analysis. The crystal structure of (apcpa)PtCl2(OCOC2H5)2 (monoclinic, P21 (No. 4), a = 9.1391(1), b = 22.2517(1), c = 10.0687(1)Å, β= 109.105(1)。 , V = 1934.80(3)Å3 , Z = 4, R1 = 0.0532) exhibits that the platinum atom achieves a typical octahedral arrangement with two nitrogen atoms in cis positions and two carboxylato group in trans positions. The spectroscopic data disclose that these platinum(IV) complexes are stable and their molecular structures are retained in aqueous solution. The title complexes are highly cytotoxic in vitro but do not exhibit oral anticancer activity in vivo.

Two d10 Metal Coordination Polymers Based on 1H-1,2,4-Triazole: Synthesis, Structure and Fluorescence

  • Zhang, Xiu-Cheng;Xu, Ling;Liu, Wen-Guang;Liu, Bing
    • Bulletin of the Korean Chemical Society
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    • v.32 no.5
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    • pp.1692-1696
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    • 2011
  • The reactions of 1H-1,2,4-triazole (Htr) with $MX_2$ ($ZnCl_2$ for 1; $CdBr_2$ for 2) resulted in two coordination polymers, [Zn(tr)Cl]$_n$ (1) and $[Cd(Htr)_2Br_2]_n$ (2). The structural analyses indicate that 1 and 2 feature a 2D layer and 1D triple chain, respectively. In 1, neighouring Zn atoms are connected by ${\mu}_3-1$ ${\kappa}N$: 2 ${\kappa}N$: $4{\kappa}N-tr^-$ anionic ligand into 6- and 16-membered rings, further grow into a 2D sheet. Cd atoms in 2 are bonded by two ${\mu}_2-Br^-$ bridges and neutral ${\mu}_2$-1 ${\kappa}N$: 2 ${\kappa}N$-Htr to form a 1D triple chain. The fluorescent characterizations of 1, 2 and the free Htr ligand feature simlilar emission peakes at 444, 446 and 423 nm respectively, which can be assigned to intra-ligand ${\pi}-{\pi}^*$ transition of (H)tr. The energy gaps of 5.90 eV for 1, 5.16 eV for 2, and 5.93 eV for Htr suggest that the compounds behave as insulators.

HQSAR Study on Substituted 1H-Pyrazolo[3,4-b]pyridines Derivatives as FGFR Kinase Antagonists

  • Bhujbal, Swapnil P.;Balasubramanian, Pavithra K.;Keretsu, Seketoulie;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.10 no.2
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    • pp.85-94
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    • 2017
  • Fibroblast growth factor receptor (FGFR) belongs to the family of receptor tyrosine kinase. They play important roles in cell proliferation, differentiation, development, migration, survival, wound healing, haematopoiesis and tumorigenesis. FGFRs are reported to cause several types of cancers in humans which make it an important drug target. In the current study, HQSAR analysis was performed on a series of recently reported 1H-Pyrazolo [3,4-b]pyridine derivatives as FGFR antagonists. The model was developed with Atom (A) and bond (B) connection (C), chirality (Ch), hydrogen (H) and donor/acceptor (DA) parameters and with different set of atom counts to improve the model. A reasonable HQSAR model ($q^2=0.701$, SDEP=0.654, NOC=5, $r^2=0.926$, SEE=0.325, BHL=71) was generated which showed good predictive ability. The contribution map depicted the atom contribution in inhibitory effect. A contribution map for the most active compound (compound 24) indicated that hydrogen and nitrogen atoms in the side chains of ring B as well as hydrogen atoms in the side chain of ring C and the nitrogen atom in the ring D contributed positively to the activity in inhibitory effect whereas, the lowest active compound (compound 04) showed negative contribution to inhibitory effect. Thus results of our study can provide insights in the designing potent and selective FGFR kinase inhibitors.