• The Korean Journal of Physiology
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• 제4권2호
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• pp.45-51
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• 1970

In an attempt to better understand the effect of whole body irradiation on the spontaneous motility and oxygen consumption rate of the isolated mouse duodenum, a whole body X-irradiation of 1,000r. was given to albino mouse, and 1) the total length of contraction of isolated duodenum was recorded on kymograph every five minutes for 60 minutes, 2) glucose and 5-hydroxytryptamine(5-HT) were added to the reaction medium of Kreb's-Ringer-bicarbonate buffer(KRB) and response of the isolated duodenum to the drugs was observed, and 3) the oxygen consumption rate $(QO_2)$ of the isolated duodenum as well as the effect of glucose and 5-HT on $QO_2$ were measured by Warburg's standard manometric method and the comparison was made with the control(i.e. normal) group. The results thus obtained are summarized as follows. 1. The spontaneous motility of the isolated duodenum in the irradiated groups showed a significantly elevated pattern for the first 15 minutes comparing with the control. The motility, however, decreased after 15 minutes and remained so in the irradiated groups to the level of the nonirradiated control, but 24 hours post-irradiation group showed a tendency of an increased motility while one hour post-irradiation group showed no difference comparing with the control. 2. Addition of glucose produced generally elevated motility of the isolated duodenum in both irradiated and non-irradiated groups comparing with the control throughout the experiment, but no difference was observed in contractile amplitude between the irradiated and non·irradiated groups. 3. When 5-HT was added to the irradiated group, the contractile amplitude of isolated duodenum was similar to that of the control, and 5-HT alone caused a slight increase of the motility comparing with the control. 4. The oxygen consumption rate $(QO_2)$ of the isolated duodenum was found to be ,slightly increased in one hour post·irradiated group, but similar in 24 hour post·irradiated group comparing with the control. Glucose produced a significant increase of $QO_2$ in all the groups, but 5-HT produced a tendency of decrease of $QO_2$ in all the groups.

• 대한화학회지
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• 제35권6호
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• pp.689-698
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• 1991

산소가 포화된 DMF 용매에서 다섯자리 Schiff base cobalt(Ⅱ) 착물들의 균일 산화촉매에 의한 2,6-di-tert-butylphenol의 산화주생성물은 2,6-di-tert-butylbenzoquinone(BQ)이고, 이들 균일 활성촉매는 DMSO와 pyridine 용매에서 PVT법에 의한 $O_2$/Co 몰결합비가 1:1인 superoxo형인 [Co(Ⅲ)(sal-DET)]$O_2$와 [Co(Ⅲ)(sal-DPT)]$O_2$이나 DMF 용매에서는 1:1.52이고 고체상태에서는 1:2인 ${\mu}$-peroxo형으로 주어진다. 또한 0.1M TEAP-DMSO와 0.1 M TEAP-Py의 지지전해질 용액에서 유리질 탄소전극을 사용한 순한전압전류법과 DPP법에 의한 superoxo형인 균일산화 활성 촉매들의 전기화학적 특성은 $O_2$-의 prewave을 포함한 네단계 환원과정으로 일어난다.

• Journal of Photoscience
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• 제7권4호
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• pp.135-138
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• 2000

The photochemical behavior of haloarene tethered to alkyl by an amide bone(1,2) was studied. The photoreaction of N-(2-bromophenyl) cyclohexanecarboxamide (1b) in basic medium afforded intramolecular substitute product, 2-cyclohexylbenzoxazole (4) and reduced product, N-phenylcyclohexanecarboxamide (5)in 33 and 26% yield, respectively. The chloro analogue(1a) produced photo-Fries type and photosubstituted products(6,4), whereas the iodo analogue produced extensively photoreduced product 5. N-(2-bromophenyl)-N-methylcyclohexanecarboxamide (2), which can not exist as imidol form, produced a photocyclized product, supporting as imidol form is involved in the intramolecular photosubstitution. since the photoreduction but the photosubstitution reaction is retarded by the presence of oxygen, a trilpet state for the photoreduction and a singlet state for the photosubstitution are involved.

• Journal of Photoscience
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• 제9권2호
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• pp.424-426
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• 2002

Recently, much attention has been paid to the physiological functions of flavonoids associated with their antioxidant properties. However, there was a lack of information on the molecular mechanism at which flavonoids play the antioxidative role. We have already studied on the oxidation of quercetin with hydrogen peroxide and sodium hypochlorite in alcoholic aqueous solution and determined the oxidation products. Through the structural analysis of the oxidation products, it was clarified that the hydroxyl group at C-3 in the C ring plays the important role in the antioxidative action of quercetin. Successively, rutin and (+)-catechin were oxidized with sodium hypochlorite and their mono- and di-chlorinated derivatives were obtained. These facts indicate that these flavonoids can directly scavenge hypochlorous acid and the active site in this scavenging reaction is not the hydroxyl group at C-3.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제33회 KOSCO SYMPOSIUM 논문집
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• pp.253-259
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• 2006

The effect of DC electric fields on the flame extinction was investigated experimentally in counterflow configurations for the methane/oxygen/nitrogen diffusion flame. The electric fields was applied by connecting the high voltage and ground terminals to the upper and lower burners, respectively. In case of having electric fields, several modes of flame extinction was observed according to the electric field intensity and strain rate defined by the exit velocity. To visualize and characterize the flame structure and intensity, planar LIF technique was adopted for OH radicals. Consequently, several length scales, including the flame width, thickness, and height from the burner tip, were introduced to explain the various flame behaviors and to characterize the flame extinctions. It was found that the variation of flame width and the chemical reaction are strongly related to a critical electric field intensity, thus the various modes of diffusion flame extinction could be observed due to the electric fields.

• 한국표면공학회지
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• 제34권5호
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• pp.499-502
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• 2001

Functionally gradient NiCrAlY/$ZrO_2$-$Y_2$$O_3$ and NiCrAlY/$ZrO_2$- $CeO_2$-$Y_2$$O_3$ coatings were prepared by APS. The as-sprayed microstructure consisted of metal-rich and ceramic-rich regions, between which $Al_2$$O_3$-rich layers existed owing to the oxidation during APS. During oxidation between 900 and $1100^{\circ}C$ in air, the pre-existing $Al_2$$O_3$-rich scales grew, due mainly to the preferential reaction of Al with inwardly transporting oxygen along the heterogeneous phase boundaries. As the amount of ceramics in the coating increased, the oxidation resistance increased.

• 한국태양에너지학회 논문집
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• 제30권3호
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• pp.90-97
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• 2010

$TiO_2$ thin films for solar energy utilization were prepared on ITO coated glass by r.f magnetron sputtering with variations of working pressure, oxygen flow rate and annealing temperature. Ion insertion and extraction reaction, and ion storage properties of films were investigated by using a cyclic voltammetry. Transmittance of thin films in as-prepared, colored and bleached states was measured by UV-VIS spectrophotometer. The samples deposited in our sputtering conditions showed poor electrochromic properties. Improvement in ion storage properties of $TiO_2$ thin film was observed after annealing at temperature of $400^{\circ}C$ in air for 2 hours. It was found that $TiO_2$ thin film in electrochromic device could be used as a passive counter-electrode.

• 한국가스학회지
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• 제15권6호
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• pp.51-56
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• 2011

울산의 한 실험실에서 3년 전에 혼합가스용기(80% 아르곤 20% 산소)가 파열되었다. 그러나 파열의 원인이 명확하게 규명되지 못하였다. 이 논문은 공인 감정기관의 감정서와 경찰의 수사결과보고서를 토대로 사고시나리오를 제시하여 보았다. 폭발은 혼합가스 용기 내에서의 화학반응에 의하여 발생한 것으로 판단된다. 이는 고압산소용기의 파열사고들과 유사한 것으로 사료된다.

• 제어로봇시스템학회논문지
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• 제13권11호
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• pp.1128-1136
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• 2007

This paper presents an application study of a model predictive control based commercial package PCTP to real chemical processes. The first case study concerns a product purity control of a splitter process which distillates styrene from undesired component ethyl-benzene produced from ethyl-benzene dehydrogenation reaction. The second case study is about a temperature control of ethyl-benzene dehydrogenation reactor and an excess oxygen control of the fired heater. Optimum control structure for MPC application is developed for each case study. The application results show a significant improvement in control performance and stability.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.161-164
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• 2014

The feasibility of a molten metal as a bed material of a pyrolysis system was investigated. The molten metal has various advantages such as high thermal conductivity, wide operating range and low viscosity. Tin was selected since its physical characteristics are suitable for the purpose. As a results, it was found that pyrolytic oil yield and reaction rate were significantly enhanced with the molten Tin. In addition, oxygen component of the product oil was decreased due to Tin oxidation.