• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.3-10
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• 1989

In order to obtain a clue in understanding enzymatic hydrolysis in which the His-Cys moieties of papain protease is involved, we prepared cationic peptide-sufactants bearing histidyl, cysteinyl, and both histydyl and cysteinyl residues. Their catalytic efficiency toward the hydrolysis of PNPL were investigated in comicellar phases formed with $N^{+}C_{2}CysC_{12}$, $N^{+}C_{2}HisC_{12}$, $N^{+}C_{2}HisCysC_{12}$ increased markedly in the same order compared with that of $N^{+}C_{2}AlaC_{12}$. The markedly increased catalytic effects are attributed to the imidazole groups of $N^{+}C_{2}HisC_{12}$ and the thiol groups of $N^{+}C_{2}CysC_{12}$, and the large catalytic efficiency of $N^{+}C_{2}HisCysC_{12}$, is considered due to the interaction of the imidazole and the thiol groups. In order to investigate catalytic activities, rate constants for the functional groups, km* and dissociation constants, pKa have been determined. The results showed that $k^{\ast}_m$ and pKa of the imidazole groups were $7.91{\times}10^{-4}S^{-1}$ and 6.49, and those of the thiol groups were $6.00{\times}10^{-4}S^{-1}$ and 10.50. The catalytic effects of comicellar systems on the hydrolysis of p-nitrophenyl esters has increased according to the increasing size of the alkyl carbon number. Therefore, the catalytic effects have been increasing by the interaction of micellar hydrophobic parts and substrates as well as action of the functional groups.

• Journal of Microbiology
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• v.35 no.3
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• pp.188-192
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• 1997

The strain of S-47 degrading 4-chlorobenzoic acid (4CBA) was isolated from Ulsan chemical industrial complex by enrichment cultivation with 1 mM 4CBA. The strain was Gram-negative rod and grew optimally at 30.deg.C and pH 7 under aerobic condition, so that the organism was identified as a species of Pseudomonas. Pseudomonas sp. S-47 degraded 4-chlorobenzoic acid to produce a yellow-colored meta-cleavage product, which was confirmed to be 5-chloro-2-hydroxymuconic semialdehyde (5C-2HMS) by UV-visible spectrophotometry. 5C-3HMS was proved trometry. This means that Pseudomonas sp. S-47 degraded 4CBA via 4-chlorocatechol to 5C-2HMS by meta-cleavage reaction and then to 5C-2HMA by 5C-2HMS dehydrogenase.

• Journal of Korean Neurosurgical Society
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• v.57 no.4
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• pp.276-282
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• 2015

Objective : The purpose of this study was to investigate morphological change at the craniovertebral junction (CVJ) region using computed tomography. Methods : A total of 238 patients were included in this study, and mean age was $47.8{\pm}21.3months$. Spinal canal diameter, Power's ratio, McRae line, antero-posterior C1 ring height, atlantoaxial joint space, C2 growth, epidural space from the dens (M-PB-C2) and longitudinal distance (basion to C2 lower margin, B-C2) were measured. The mean value of each parameter was assessed for individual age groups. The cohorts were then divided into three larger age groups : infancy (I) (${\leq}2years$), very early (VE) childhood (2-5 years) and early (E) childhood ($5{\geq}years$). Results : Spinal canal diameter increased with age; however, this value did not increase with statistical significance after VE age. A significant age-related difference was found for all C2 body and odontoid parameters (p<0.05). Mean McRae line was 8.5, 8, and 7.5 mm in the I, VE, and E groups, respectively. The M-PB-C2 line showed up-and-down dynamic change during early pediatric periods. Conclusion : Expansion of the spinal canal was restricted to the very early childhood period (less than 5 years) in the CVJ region; however, the C2 body and odontoid process increased continuously with age. The above results induced a dynamic change in the M-PB-C2 line. Although C2 longitudinal growth continued with age, the McRae line showed relatively little change.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.4
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• pp.62-66
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• 1989

$Bi_2S_3$ polycrystalline and $Bi_2S_3$ amorphous thin tilm were grown by the evaporation method. The measured lattic parameters were $a=1.708{\AA},\;b=0.351{\AA},\;and\;C=3.943{\AA}$ at substrate temperature $210^{cric}C$ were shown to have the orthorhombic structure. The energy gape of $Bi_2S_3$ polycrystalline that was made from thin film were measured to be 1.375eV at $289^{cric}K.$ The optical band gap of $Bi_2S_3$ amorphous thin film was measured to be 1.71eV at $289^{cric}K.$ It was supposed to mechanism that a photon absorption was changed at the center of 674nm (1.84eV)

• Journal of the Korean Vacuum Society
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• v.3 no.3
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• pp.264-268
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• 1994

본연구에서는 HCl 또는 NH4OH로 산화막을 식각학 GaAs 표면에 H2S 가스를 이용하여 유황처 리하였다. 표면의 화학적 조성 및 결합상태를 측정하기 위하여 AES 및 XPS를 사용하였다. 시편들은 30,200 및 $350^{\circ}C$로 가열하면서 H2S가스와 반응시켰다. 이때 유황은 GaAs 표면의 Ga 원자 및 As 원자 와 화학결합을 형성하고 있음이 밝혀졌다. 또한 $350^{\circ}C$로 가열된 시편이 $30^{\circ}C$ 또는 $200^{\circ}C$로 가열된 시편 보다 표면에 결합된 유황의 양이 많은 것으로 나타났다. 아울러 (NH4)2S 수용액 또는 Na2S 수용액으로 유황처리된 경우와 동일하게 H2S 가스로 유황처리된 GaAs 표면에서는 Ga 산화막 및 As 산화막이 거 의 관측되지 않았다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.02a
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• pp.60-63
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• 2004

Sulfurization of rare-earth oxides R203 (R=Nd, Eu) using sulfurizing reagents, such as $H_2S$ and $SC_2$was examined for the sulfide magnetic separation of spent fuel. $EU_2O_3$was found to react with H$_3$S gas forming the mixture of $EU_2O_2S$ and EuS at 500 oC, while EuS was formed by $SC_2$ at 800 oC. In the case of the mixture of $R_2O_3$and $UO_2$, EuS and $ND_3S_4$ were formed as well as $EU_2O_2S$ and $Nd_2O_2S$ at 500oC in $H_2S$, though $UO_2$ remained unreacted.

• Journal of the Korean housing association
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• v.12 no.2
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• pp.191-198
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• 2001

The aim of this research was to examine the thermal performance of the flat roof in proportion to various directional changes, the results of which were drawn from the miniature model experiment. In this process, various thermal environmental factors were measured and compared with one another to research their aspects of changes. The brief results of this research are as follows: 1) The indoor temperature and load per hour in proportion to directional changes shows the same degree of changes. As for the results of the clear-sky and cloudy-sky experiments, both of them generally appear advantageous in the order of S, $S-30^{\cire}C$-E, $S-30^{\cire}C$-W, $S-60^{\cire}C$-W, E, $S-60^{\cire}C$-E, despite slight differences in the indoor temperature and load per hour in proportion to directional changes. 2) As for the total load of degree day per direction of the clear-sky and cloudy-sky experiments, both of them shows their advantageous results in the order of S, $S-30^{\cire}C$-E, $S-30^{\cire}C$-W, $S-60^{\cire}C$-W, E, $S-60^{\cire}C$-E, despite minor differences in their loads. 3) As for the peak load of degree hour, while the clear-sky experiment shows its advantage in the order of $S-30^{\cire}C$-E, S, $-30^{\cire}C$-W, $S-60^{\cire}C$-W, E, $S-60^{\cire}C$-E, the cloudy-sky experiment does so in the order of S, $S-30^{\cire}C$-E, $S-30^{\cire}C$-W, E, $S-60^{\cire}C$-W, $S-60^{\cire}C$-E.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.725-728
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• 1996

This study was conducted to investigate effect of leaf temperature on light response and respiration during short-term exposure to a sequnce of PPFD cycle(100-200-300-400$\mu$ mol m$^{-2}$ s$^{-1}$ ) under increasing leaf temperature sequnce up to 3$0^{\circ}C$ and in dark condition, increasing up to 46$^{\circ}C$ with step size (1$^{\circ}C$) in Panax ginseng C. A. Meyer. When leaflet exposed to low light intensity and temperature, Rubisco activity was higher than remained activity in high condition. Leaves adapted to 100$\mu$mol m$^{-2}$ s$^{-1}$ PPFD had a peak response similar to that of 200$\mu$mol m$^{-2}$ s$^{-1}$ at 18$^{\circ}C$, but in above PPFD cycle(300, 400$\mu$mol m$^{-2}$ s$^{-1}$ ) it represented at 17$^{\circ}C$ and 16$^{\circ}C$, re-spectively. $CO_2$ evolution in dark condition increased rapidly when leaf temperature was increased up to 28$^{\circ}C$ and then 'dipped' below steady-state level from above 4$0^{\circ}C$. Thus, Pananx ginseng is able to take advantage of irradiance increase and decrease of $CO_2$ evolution in dark condition to control leaf temperature.mperature.

• Journal of the Korean Chemical Society
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• v.41 no.3
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• pp.150-156
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• 1997

A precursor of bulgecinine, (4S,5R)-1-acetyl-2-formyl-5-benzyloxymethyl-4-pyrrolidinol (15) has been synthesized from diacetone-D-glucose. Barton deoxygenation, conversion to an L-sugar and displacement with $N_3^-$ at C-5, and one-pot reductive cyclization at C-2 produced (6R)-6-Ο-benzyloxymethyl-(3R)-3-methoxy-2-oxa-5-azabicyclo-[2,2,1]heptane(13), a key intermediate for bulgecinine. N-Acetylation and acid hydrolysis of 13 furnished a precursor of bulgecinine, (2S,4S,5R)-pyrrolidinol derivative 15 and its (2R,4S,5R)-diastereomer.

• Journal of the Korean Society of Radiology
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• v.6 no.6
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• pp.521-529
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• 2012

The aim of this study was to analyze radiological change of Kager's triangle area and retrocalcaneal surface temperature by shoes heel height. Area of Kager's triangle was measured by simple radiography study And PACS of INFINITI. Retrocalcaneal surface temperature were measured by DITI. Area of Kager's triangle and retrocalcaneal surface temperature were calculated for comparison and analysis, with flat shoes and high heel shoes. Area of Kager's triangle($0.88cm^2$) and retrocalcaneal surface temperature ($1.4^{\circ}C$)tends to decrease with high heel shoes. The highest and shortest of the Kager's triangle area and a surface temperature difference between flat shoes and high heel shoes, each $0.9cm^2$, $1.2cm^2$, $1.6^{\circ}C$, $0.5^{\circ}C$ and showed slight differences. The highest weight and the lowest weight of a surface area and the temperature difference between flat shoes and high heels, each $1.8cm^2$, $0.8cm^2$, $1.1^{\circ}C$, $0.2^{\circ}C$ and higher weight Kager's area and the surface temperature is decreased. The longest time and shortest time of a surface area and the temperature difference between high heels, each $0.8cm^2$, $1.4^{\circ}C$. In conclusion, Areas of Kager's triangle and retrocalcaneal surface temperature decrease with high heel shoes. If we wear high heel shoes for a long time, retrocalcaneal pain and blood flow disorder will occurs.