• The korean journal of orthodontics
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• v.31 no.4 s.87
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• pp.447-458
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• 2001

The purpose of this study was to evaluate 1) in vivo, the expression of chondroitin 4-sulfate (CH-4S), a structural element of glycosaminoglycans(GAGs), in periodontal tissue during the experimental movement of rat incisors, by labelled streptavidine biotin immunohistochemical staining for CH-4S, 2) In vitro, the expression of CH-4S in cultured human periodontal ligament(PDL) cells supplemented with 10ng/ml of $TGF-{\beta}_1$, 20ng/ml of PDGF-BB, 1ng/ml $TNF-\alpha$, or $1{\mu}g/ml$ LPS by western blot analysis. The results of this study were as follows ; 1. The expression of CH-4S was stronger in pulp, PDL, osteoblasts, osteoclasts and osteocytes in experimental group than in control group, but was rare in dentin, and cementum of experimental groups, regardless of the duration of force application, which was not different from that of control group. 2. In experimental group, the expression of CH-4S in pulp began to increase at 1 day after force application and got to the highest degree at 7 days. After 14 days, the expression in CH-4S immunoreactivity was decreased, and became similar to that of control group at 28 days. 3. The expression of CH-4S in PDL was noted in adjacent to alveolar bone. PDL showed higher intensity of immunolabelling after 1 day of orthodontic tooth movement. And the expression was more stronger in the tension side than that of pressure side of PDL at 1 day, but more stronger in the pressure side than that of tension side of PDL at 4 days. After 7 days, a decrease in CH-4S expression was observed. 4. The expression of CH-4S in alveolar bone got to the highest degree at 4 days, and At 7 days, a decrease in CH-4S expression was observed. 5. PDGF-BB notably raised the expression of CH-4S in the PDL cells at 3 days of cultivation 6. The expression of CH-4S of PDL cells was decreased with the application of $TNF-\alpha$ at 1 day. 7. Admixture of $TGF-{\beta}_1$ and PDGF-BB got more expression of CH-4S in PDL as compared to only $TGF-{\beta}1$ or PDGF-BB. A similar decrease of the expression of CH-4S was observed in the case of application of LPS or $TNF-\alpha$.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.317-326
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• 2000

Carbonyl compounds have been measured in downtown Seoul for September 1998 using 2-series impinger method. Average concentration (ppbv) of carbonyl compounds were 12.66$\pm$5.77 HCHO, 12.05$\pm$4.86 CH3CHO and 7.92$\pm$2.63 CH3CHCH3 These compounds were the most abundant carbonyl,. They showed maximum concentration during the daytime when photochemical activity was very strong minimum concentration were usually showed during the night and early morning. Comparison of diurnal variation of carbonyl compounds with the concentration of O3, NMHC, CO and meteorological data indicated that primary and secondary sources contributed the observed carbonyl compounds. Photochemical Formation Rate(PFR) of carbonyl compounds dur-ing the sampling periods were 61% HCHO, 85% CH3CHO, 85% CH3CHO, 71% CH3COCH3.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.311-316
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• 1997

The synthesis and characterization of the mononuclear group 13 heterocyclic carboxaldehyde methyldithiocarbazate complexes Me2M[NC5H4CRNNC(S)SCH3] (M=Al, R=H(1); M=Ga, R=H(2); M=Al, R=CH3(3); M-Ga, R=CH3(4); M=In, R=CH3(5)) are described. Compounds 1-5 were prepared by the reaction of MMe3 (M=Al, Ga, In) with 2-formy or 2-acetylpyridine-S-methyldithiocarbazate in toluene. These compounds 1-5 have been characterized by microanalysis, NMR (1H, 13C) spectroscopy, mass spectra, and single-crystal X-ray diffraction. X-ray single-crystal diffraction analyses reveal that 4-5 are mononuclear metal compounds with coordination number of 5 and N,N,S coordination mode.

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.695-700
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• 1994

Hydrogenolysis reactions of CFC-113a catalyzed by various heterogeneous catalysts $(Rh/Al_2O_3,\;Pd/C,\;Ni,\;Al_2O_3,\;Active\;carbon)$ were investigated in the liquid and gas phases. In the liquid phase reaction, different catalysts showed different activities, but all catalysts used gave high selectivities toward HCFC-123 over 95%. It was noticeable that the neutral $Al_2O_3$ showed both a high activity and a selectivity in the liquid phase reaction. In the gas phase reaction, transition metals on carbon(Pd/C, Pt/C) were so active for hydrogenolysis of CFC-113a that they even catalyzed the production reaction of overhydrogenated compounds such as $HCFC-133a(CF_3CH_2Cl)\;and\;HFC-143a(CF_3CH_3)$. $Al_2O_3$, which showed the high activity in the liquid phase reaction, did not show a remarkable activity. When $Al_2O_3$ was used in the liquid phase reaction, the hydrogenolysis of CFC-113a proceeded without any side products in THF. However, the same reaction in MeOH produced side products, such as $CH_3OCH_3\;and\;CH_3CH_2OCH_3$ from solvent. Based on this result, including heterogeneous catalysts, it was concluded that the solvent played an important role in the liquid phase reaction.

• Journal of the Korean Chemical Society
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• v.24 no.2
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• pp.139-145
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• 1980

High spin iron(II) complexes of 1,4,8,11-tetraazacyclotetradecane (cyclam), a macrocyclic ligand, and 1,5,8,12-tetraazadodecane (3,2,3-tet), a noncyclic ligand, have been prepared. The reaction of low spin $[Fe(cyclam)(CH_3CN)_2](ClO_4)_2$ with chloride ion in methanol produces high-spin $[Fe(cyclam)Cl]ClO_4$. Although $[Fe(cyclam)(CH_3CN)_2](ClO_4)_2$ is low spin, $[Fe(3,2,3-tet)(CH_3CN)_2](ClO_4)_2$ isolated in the present study is high spin. This difference is explained in terms of the smaller constrictive effect exerted by the noncyclic ligand than the cyclic ligand. The isolation of $[Fe(cyclam)Cl]ClO_4$ provides evidences against the current view that the presence of either unsaturation or substituents on the macrocyclic ligands is necessary for the successful preparation of high spin five-coordinate iron (II) complexes. Reactions of $[Fe(cyclam)Cl]ClO_4\;and\;[Fe(3,2,3-tet)(CH_3CN)_2](ClO_4)_2$ with carbon monoxide yield low spin six-coordinate $[Fe(cyclam)Cl(CO)]ClO_4\;and\;[Fe(3.2,3-tet)(CH_3CN)(CO)](ClO_4)_2$, respectively.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.580-587
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• 1994

The oxidative coupling of methane was studied kinetically using $Na^+(50wt%)/MgO$ catalyst at 710, 730, 750, 770 and $790^{\circ}C$ in a fixed bed flow reactor at the atmospheric pressure under differential conversion conditions. Through curve fitting, it was found that the Langmuir-Hinshelwood type mechanism was fitted to this reaction rather than Rideal-Redox type or Eley-Rideal type mechanism. Therefore, it was proposed that the $O_2{^-}$ or $O_2{^{2-}}$ species on the surface was related to the production of $CH_3{\cdot}$. The estimated activation energy of $CH_3{\cdot}$ production was about 39.3kcal/mol. Moreover, as the result of curve fitting, the stoichiometric coefficient of $O_2$ for the production of $CH_3{\cdot}$ to produce $CO_x$was approximately 1.5. Accordingly, it could be concluded that the $CH_3O_2{\cdot}*$ was prouduced through the partial oxidation of $CH_3{\cdot}$ with the surface oxygen.

• Journal of the Korean Chemical Society
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• v.39 no.10
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• pp.769-775
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• 1995

The reaction between $CH_3$ radicals and $O_2$ was investigated in incident shock waves at temperatures between 1390 and 2250 K and densities from 1.5 to 5.3 mol/$m^{+30/3}$ using azomethane as a source of methyl radicals by following the consumption of CH3 radicals with time resolved UV absorption measurements at 213.9 nm. The rate constant expression $k_2=1.35{\times}10^{12}\;exp( - 5900 K/T)\;cm^3 mol^{-1}s^{-1}$ for the reaction of $CH_3 + O_2{\rightarrow}CH_2O + OH$ was derived.

• Journal of the Korean Society of Costume
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• v.25
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• pp.117-118
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• 1995

Chinese shroud through literatures are as follows. 1. Taetae, Sime i, P'oo, Hansam, Ko, Mal, Nukpaek, Kwatu, Cu'ungi, Pokk n, Myokmok, Ri, Aksu, Mo and m were used the most in China. 2. The cloths of Chinese shroud were p'o, Paek, Kyon and Kum. The colors of the Chinese shroud were Hyon, Hun and white. 3. The size of the Chinese shroud is as follows. The size of the Ch'ungi was similar to the size of jujube kernel, the length of Myokmok was one Ch' k two Ch'on or one Ch' k five Ch'on, the length of Aksu was one Ch' k two Ch'on and it's width was five Ch'on. The chil of Mo reached the hands and the length of Swae was three Ch' k and the length of m was five Ch'on. 4. In Chinese shroud, cotton was put in P'oo, Aksu was tide by the strings at two corners. Myokmok was tied by the strings of four corners. The tip of the m was divided and Mo wrapped the whole body. 5. The clothes of Soryom was nineteen Ch'ing. The clothes of Taeryom in Kun were one hundred Ch'ing in the Chinese. The impliment of Soryom were Kum, Kyo, Sange i, Sane i, Ch'im, Yok and Kyon in the Chinese shroud. In the case of the implement of Taeryom, the chinese shroud had Kum, Kyo, Sange i, Sane i, Ch'im and Yok.

• Journal of environmental and Sanitary engineering
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• v.23 no.3
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• pp.39-46
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• 2008

In order to study the estimate of $CH_4$ emission factors in the municipal wastewater treatment plants, the active sludge process, 5-stage process, Denipho process, and SBR process were investigated. When active sludge process, 5-stage process, and Denipho process were used in wastewater treatment plant, the $CH_4$ emission factors were 2.88, 1.61, and 0.57 g-$CH_4/kg$-BOD, respectively. On the other hand, in the case of SBR process, it was 4.14 g-$CH_4/kg$-BOD. These results indicate that SBR process was effective for $CH_4$ emission in municipal wastewater treatment plants. Using the above processes, the methane emission factor and amount of waste water sludge were $4.78m^3/t$ and $12,204,506m^3/yr$, respectively. The remove of BOD was a range of $93.91{\sim}98.63%$.

• Journal of the Korean Chemical Society
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• v.39 no.5
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• pp.393-398
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• 1995

The oxo-nitrosyl complexes (n-Bu4N)2[M4O12Mo(NO)2{RC(NH2)NHO}2{RC(NH)NO}2] (M=Mo, W; R=(CH3)2CH, n-CH3CH2CH2) have been prepared by the reactions of monomeric complex containing {Mo(NO)2}2+ and polyoxometalates with isobutyl- and n-butylamidoxime. The prepared complexes were characterized by elemental analysis, infrared, 1H NMR, 13C NMR and UV-visible spectroscopy. These complexes contain two {M2O5}2+ [M=Mo, W] cores and a central {Mo(NO)2}2+ core. The {Mo(NO)2}2+ unit was the formally cis type and C2v symmetry in geometric structure. The two {M2O5}2+ cores and a central {Mo(NO)2}2+ core were not nearly interacted with electronic localization, which were identified by spectroscopy.