• Title/Summary/Keyword: C2H

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Effect of Incubation Temperature and pH on Chlamydospores Germination of Cylindrocarpon destructans Causing Root Rot of Panax ginseng (인삼 뿌리썩음병균 Cylindrocarpon destructans의 후막포자 발아에 미치는 배양온도 및 pH의 효과)

  • 조대휘;유연현
    • Journal of Ginseng Research
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    • v.25 no.3
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    • pp.136-140
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    • 2001
  • Effects of incubation temperature and pH on chlamydospore germination of Cylindrocarpon destrcutans (isolate CY-9802) causing root rot of Panax ginseng were studied. Germination rate of the chlamydospores on Czapek solution agar(CSA) was higher than on potato dextrose agar(PDA) at the incubation temperatures tested. The chlamydospores were able to be germinated at range of 5$\^{C}$ to 30$\^{C}$ after 48 hours incubation on CSA. Germination rate was 53.2∼6.27% at range of 15$\^{C}$ to 25$\^{C}$, and the optimum temperature was 20$\^{C}$, whereas they were very low at 30$\^{C}$ on PDA. Germination rate was 43.6% to 47.9% at range of 10$\^{C}$ to 20$\^{C}$, and the optimum temperature was 20$\^{C}$ as well. They were able to be germinated at pH of 5.2 to 8.1 on CSA and 5.2 to 7.2 on PDA. Optimum pHs for the germination on CSA and PDA were from 6.4 to 8.2 and from 5.2 to 6.0, respectively. Mycelial color of the fungus on CSA was pale brown at pH from 5.2 to 6.0 and white from pH 6.4 to 8.1, while it was typical dark brown ar range of pH 5.2 to 7.1 and brown at pH 7.2 on PDA after 21 days incubation.

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Calculation of the Ideal Positions of Hydrogen Atoms in Compounds (화합물내에서의 수소원자의 이상적 위치계산)

  • Suh Il-Bwan;Kim Kyung-Han;Oh Mi-Ran;Park Koon Ha;Kim Moon-Jib
    • Korean Journal of Crystallography
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    • v.8 no.1
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    • pp.59-63
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    • 1997
  • A method for the calculation of the idealized hydrogen positions in the following seven different kinds of compounds has been shown: (1) tertiary C-H, (2) secondary C-H, (3) $CH_3$ group with tetrahedral angles, (4) aromatic C-H or amide N-H, (5) O-H group with X-O-H angle tetrahedral, (6) terminal $X=CH_2$ or $X=NH_2^+$ with the hydrogen atoms in a plane and (7) acetylenic C-H with X-C-H linear.

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Molecular Structure of PCP Pincer Complexes: Poisoning Catalyst on the Dehydrogenation of Alkanes (알칸의 탈수소화반응에서의 촉매독 화합물의 분자구조)

  • Lee Ji Hyun;Chun Sang Jin;Kwon Ki Hyeok;Lee Do Weon
    • Korean Journal of Crystallography
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    • v.16 no.1
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    • pp.43-53
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    • 2005
  • The dihydrido P-C-P pincer complex, $IrH_2{C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (1), was successfully prepared from the reaction of the hydrochloride complex, $IrClH (C_6H_3-2,6-(CH_2PBu_2^t)_2}$, and super acid $(LiBEt_3H)$ under 1 atm of hydrogen in pentane solution at room temperature and followed by Heating at $130^{\circ}C$ in vacuo. Jensen recently found that the dihydrido P-C-P pincer complex 1 is a highly active homogeneous catalyst for the transfer dehydrogenation of alkanes with unusual longterm stability at temperatures as high as $200^{\circ}C$. The treatment of dihydrido complex 1 with nitrogen, water, carbon dioxide, and carbon monoxide in presence of tert-butylethylene (the) at room temperature in an appropriate solution gave the dinitrogen complex, $[Ir{C-6H_3-2,6-(CH_2PBu_2^t)_2}]_2({\mu}-N_2)$ (2), the hydrido hydroxyl complex, $IrH(OH){C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (3), the carbon dioxide complex, $Ir({\eta}^2-CO_2) {C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (including the bicarbonate complex, $IrH({\kappa}^2-O_2COH){C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(4))$, and the carbonyl complex, $Ir(CO) {C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(5)$ (including the carboxyl complex, $IrH(C(O)OH) {C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(6))$, in good yield, respectively. These P-C-P iridium complexes were isolated and characterized by $^1H,\;^{13}C,\;^{31}P\; NMR$, and IR spectroscopy. In addition, the complexes (1-6) were characterized by a single crystal X-ray crystallography. These complexes account for these small molecules' inhibition of dehydrogenation of alkanes catalyzed by the dihydrido complex 1.

Variation of SiC/C FGM Layers (SiC/C 경사기능재료 증착층의 변화)

  • Kim, Yu-Taek;Jeong, Sun-Deuk;Lee, Seong-Cheol;Park, Jin-Ho
    • Korean Journal of Materials Research
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    • v.8 no.6
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    • pp.477-483
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    • 1998
  • $SiC_{4}$$C_{3}$$H_{ 8}$$H_{2}$$C_{3}$$H_{8}$ $H_{2}$, $CH_{3}$$SiCI_{3}$$CH_{4}$$H_{2}$계를 사용하여 흑연기판 위에 SiC와 SiC/C FGM을 CVD법에 의해 코팅하였다. $SiCI_{4}$$C_{3}$$H_{8}$ $H_{2}$ 계에서 SiC 증착 시 바람직한 수소의 비는 10-30사이였고 결정 배향성은 입력가스의 탄소비에 따라 여러번의 대 반전이 일어났다. 성장조건을 {111} 배향성을 갖도록 조절하는 것이 FGM층간 접착상태를 증진시킬 수 있는 방법으로 판단되었다. $CH_{3}$$SiCI_{3}$C$_{3}$$H_{8}$ $H_{2}$ 계에서는 SiC와 C의 비율을 조절하기가 $SiCI_{4}$$C_{3}$$H_{8} $H_{2}$계를 사용했을 때 보다 용이하였고, FGM 단면 관찰에서 층간의 뚜렷한 경계를 발견할 수 없을 정도로 우수한 층간 접착상태를 보였다.

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Iridium(Ⅲ) Complexes of η$^6$-Arenes with Olefinic and Cyclopropyl Substituents: Facile Conversion to η ³-henylallyl Complexes

  • 정현목;주광석;진종식
    • Bulletin of the Korean Chemical Society
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    • v.18 no.4
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    • pp.402-405
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    • 1997
  • Olefinic and cyclopropyl group substituted arenes (C6H5Y) react with [Cp*Ir(CH3COCH3)3]A2 (A=ClO4-, OTf-) to give η6-arene complexes, [Cp*Ir(η6-C6H5Y)]2+ (1a: Y=-CH=CH2 (a),-CH=CHCH3 (b),-C(CH3)=CH2 (c),-CH-CH2-CH2 (d)). Complex 1b-1d are readily converted into η3-allyl complexes, [Cp*(CH3CN)Ir(η3-CH(C6H5)CHCH2)]+ (2a) and [Cp*(CH3CN)Ir(η3-CH2(C6H5)CH2)]+ (2b), in the presence of Na2CO3 in CH3CN. The η6-styrene complex, 1a reacts with NaBH4 to give η5-cyclohexadienyl complex, [Cp*Ir(η5-C6H6-CH=CH2)]+ (3), while with H2 it gives η6-ethylbenzene complex [Cp*Ir(η6-C6H5CH2CH3)]2+ (4). Complex 1a and 1c react with HCl to give [Cp*Ir(η6-C6H5CH2CH2Cl)]2+ (5a) and [Cp*Ir(η6-C6H5CH(CH3)CH2Cl]2+ (5b), respectively.

Fe-H…H-C Dihydrogen Bondings: Synthesis and Structure of trans-[FeH(NCSe)(dppe)2](dppe=Ph2 PCH2 CH2 PPh2 (Fe-H…H-C 이수소 결합: trans-[FeH(NCSe)(dppe)2](dppe=Ph2 PCH2 CH2 PPh2의 합성 및 구조)

  • Baek, Ji Yeong;Han, Won Seok;Lee, Sun Won
    • Journal of the Korean Chemical Society
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    • v.46 no.5
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    • pp.427-436
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    • 2002
  • Reaction of $trans-[FeHCl(dppe)_2]$ (1) with KSeCN led to the formation of $trans-[FeH(NCSe)(dppe)_2](2).$ Compound 2 $·CH_2Cl_2$ was structurally characterized by X-ray diffraction, in which the hydride ligand appears to be involved in the dihydrogen bonding of the type M-H${\cdot}$${\cdot}$${\cdot}$H-C.

Study on Environmental Hazards of Alternatives for PFOS (PFOS 대체물질의 환경유해성에 관한 연구)

  • Choi, Bong-In;Chung, Seon-Yong;Na, Suk-Hyun;Shin, Dong-Soo;Ryu, Byung-Taek
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.6
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    • pp.317-322
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    • 2016
  • While PFOS sodium salt ($C_8F_{17}SO_3Na$) was not degraded by microorganisms for 28 days, the 4 alternatives were biodegraded at the rates of 21.6% for $C_{25}F_{17}H_{32}S_3O_{13}Na_3$, 20.5% for $C_{15}F_9H_{21}S_2O_8Na_2$, 15.8% for $C_{23}F_{18}H_{28}S_2O_8Na_2$ and 6.4% for $C_{17}F_9H_{25}S_2O_8Na_2$, respectively. The acute toxicity test using Daphnia magna was conducted for 48 hours, the half effective concentration ($EC_{50}$) of PFOS sodium salt ($C_8F_{17}SO_3Na$) was evaluated in 54.5 mg/L. While the 4 alternatives did not show any effect at 500.0 mg/L. The surface tension of the PFOS salt ($C_8F_{17}SO_3Na$) is 46.2 mN/m at a concentration of 500.0 mg/L. While the surface tension of the 4 alternatives was found to be superior to PFOS sodium salt ($C_8F_{17}SO_3Na$). The surface tension of $C_{23}F_{18}H_{28}S_2O_8Na_2$ (20.9 mN/m) has the lowest, followed by $C_{15}F_9H_{21}S_2O_8Na_2$ (23.4 mN/m), $C_{17}F_9H_{25}S_2O_8Na_2$ (27.3 mN/m), $C_{25}F_{17}H_{32}S_3O_{13}Na_3$ (28.2 mN/m). The four kinds of alternatives ($C_{15}F_9H_{21}S_2O_8Na_2$, $C_{17}F_9H_{25}S_2O_8Na_2$, $C_{23}F_{18}H_{28}S_2O_8Na_2$, $C_{25}F_{17}H_{32}S_3O_{13}Na_3$) were found to be superior to PFOS sodium salt ($C_8F_{17}SO_3Na$) in terms of biodegradation, Daphnia sp. acute toxicity and surface tension, and thus they were considered applicable as PFOS alternatives. Especially biodegradation rate of $C_{15}F_9H_{21}S_2O_8Na_2$, $C_{23}F_{18}H_{28}S_2O_8Na_2$ and $C_{25}F_{17}H_{32}S_3O_{13}Na_3$ was relatively high as 15.8~21.6%, and Daphnia sp. acute toxicity and surface tension were considerably superior (surface tension 39~55%) to PFOS sodium salt. Therefore, these alternatives are considered to be available as an alternative of PFOS.

Nucleotide and Deduced Amino Acid Sequences of Rat Myosin Binding Protein H (MyBP-H)

  • Jung, Jae-Hoon;Oh, Ji-Hyun;Lee, Kyung-Lim
    • Archives of Pharmacal Research
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    • v.21 no.6
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    • pp.712-717
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    • 1998
  • The complete nucleotide sequence of the cDNA clone encoding rat skeletal muscle myosin- binding protein H (MyBP-H) was determined and amino acid sequence was deduced from the nucleotide sequence (GenBank accession number AF077338). The full-length cDNA of 1782 base pairs(bp) contains a single open reading frame of 1454 bp encoding a rat MyBP-H protein of the predicted molecular mass 52.7kDa and includes the common consensus 1CA__TG' protein binding motif. The cDNA sequence of rat MyBP-H show 92%, 84% and 41% homology with those of mouse, human and chicken, respectively. The protein contains tandem internal motifs array (-FN III-Ig C2-FN III- Ig C2-) in the C-terminal region which resembles to the immunoglobulin superfamily C2 and fibronectin type III motifs. The amino acid sequence of the C-terminal Ig C2 was highly conserved among MyBPs family and other thick filament binding proteins, suggesting that the C-terminal Ig C2 might play an important role in its function. All proteins belonging to MyBP-H member contains `RKPS` sequence which is assumed to be cAMP- and cGMP-dependent protein kinase A phosphorylation site. Computer analysis of the primary sequence of rat MyBP-H predicted 11 protein kinase C (PKC)phosphorylation site, 7 casein kinase II (CK2) phosphorylation site and 4N-myristoylation site.

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Oxidation Reaction of CO and $C_2H_4$ on Zinc Oxide (산화아연에서의 CO, $C_2H_4$의 산화반응)

  • Chong Soo Han;Hakze Chon
    • Journal of the Korean Chemical Society
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    • v.24 no.3
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    • pp.218-224
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    • 1980
  • The surface reactions of CO and $C_2H_4$ with adsorbed oxygen on ZnO were studied by means of EPR spectroscopy. The EPR spectra of $O_2$ adsorbed ZnO at various temperatures were compared, and the signal at g = 2.014 was characterized as trapped $O^-$ at oxygen vacancy. CO and $C_2H_4$ react with $O^-$ at $25^{\circ}C$ and desorbed as $CO_2$ and $H_2O$ above $200^{\circ}C$. $O_2^-$ species interact with $C_2H_4$ about $100^{\circ}C$, but desorption of partial oxidation products also was not observed until the temperature was raised to $200^{\circ}C$.

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Studies on Cellulolytic Enzyme Producing by Ckaetomium globosum -Part 2. Purification of Cellulase- (Chaetomium globosum 이 생성하는 Cellulose 분해 효소에 관한 연구 -(제2보) Cellulase의 정제-)

  • Chung, Dong-Hyo
    • Applied Biological Chemistry
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    • v.12
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    • pp.33-41
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    • 1969
  • 1. Crude cellulase extracted from wheat bran media of Chaetomium globosum with pH 7.0 McIlvaine buffer was fractionated by precipitation with ammonium sulfate and by treatment with the cellulose powder, DEAE-Sephadex A-25 and Amberite XE-65 (IRC-50) column chromatography. 2. Consquently two cellulases C-1 and C-2 were obtained by cellulose column chromatography. Cellulose C-1 was a powerful CMC-saccharifying and CMC-liquefying activity but cellulose C-2 was stronger CMC-liquefying activity compared to CMC-saccharifying activity and cellulase C-2 had smaller protein than that of cellulose C-1. And cellulose C-2 was fractionated by DEAE-Sephadex A-25 column chromatography into cellulase C-1-1 and cellulose C-1-2. 3. It can be obtained, therefore, that cellulose produced Chaelomium globosum consisted, at least, of three cellulases C-2, C-1-1 and C-1-2. 4. Cellulose C-1-1 was homogenous in the ultraviolet and the ultracentrifuge pattern. And cellulose C-1-1 had enzyme for CMC-saccharifying activity. 5. The optimum pH for the enzyme activity of cellulose C-1-1 was 4.0 in any methods of meas urement reducing sugar and viscosity. The optimum temperature was $40^{\circ}C$ in any methods. 6. The pH stability of cellulase C-1-1 was within pH 5.0 to pH 6.0 at $40^{\circ}C$ and fairly stable in acidic solution. 7. The heat stability was below $50^{\circ}C$ at pH 4.0 and complete heat inactivation of this cellulase occurred at $70^{\circ}C$.

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