• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.983-988
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• 2005

Effects of Citrus sunki peel and its fermented product extracts on physiological and functional activities of cellular systems were investigated. Ethanol extract of Citrus sunki peel showed potent ROS-scavenging activity using 2',7'-Dichlorofluorescin diacetate as a fluorescent ROS probe in HepG2 cells. Fermented product of C. sunki peel extract markedly suppressed nitric oxide production in lipopolysaccharide (LPS)-activated RAW264.7 murine macrophage cells. Treatment with fermented product of C. sunki peel extract decreased intracellular protein levels of inducible nitric oxide synthase and cyclooxygenase II stimulated by LPS. High doses of fermented product lend to apoptotic cell death in CHO-IR cells.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.365-373
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• 2005

Antioxidative activities of methanol extracts of 7 natural products which have been orientally used or studied as ophthalmic drugs were investigated. All of 7 extracts assayed - Rubus coreanus, Dendrobium monile, Eriocaulon sieboldianum, Ligustrum japonicum, Cassia tora, Cicadae Periostacum and Polygonatum odoratum var pluriflorum had some electron-donating ability to OPPH radicals, in which R. coreanus and D. monile showed strong activity as similar as ascorbic acid or BHT. At the concentration of $200{\mu}g/m{\ell}$, methanol extract of L. japonicum showed superoxide dismutase-like activity the same as 0.1 mM ascorbic acid and methanol extract of R. coreanus inhibited effectively the production of ABTS radical produced by $H_2O_2$. Furthermore, methanol extract of C. tora showed the highest nitrite scavenging ability. The inherent antioxidative activities of these natural products appear to be responsible for its ophthalmic effects.

• Journal of Radiation Protection and Research
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• v.11 no.2
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• pp.139-145
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• 1986

An improved mothod of assessing fuel status by analyzsis of the fission product in the reactor coolant system is proposed. The release mechanism of specific fission products is established for determination of the coefficients in the equations which relate the radioactivities with the amount of defected fuel. Knock-out and migration models are employed in the formulation of the release mechanism. The influence of the tramp uranium is quantified. Sample calculations were made for KNU 1 reactor system using the I-131 and I-133 concentrations in the primary coolant. The estimated number of defected fuel pins in the third and sixth cycles appeared to be $9.34{\pm}1.13\;and\;0.294{\pm}0.092$, respectively.

• Journal of Korean Society of Archives and Records Management
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• v.16 no.2
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• pp.173-183
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• 2016

Fungi are a major cause of cultural and biological degradation in museum storages and archives libraries. In addition, fungi produce toxins and can cause skin allergies. In particular, fungi coming into contact with the skin through the hands of administrators dealing with cultural properties, archives, and books can lead to secondary infections. To prevent this, applying hand sanitizer, which is readily available in the market, is recommended. However, such hand sanitizer can effectively disinfect against bacteria but not fungi. As such, researching for an alternative is required. In this study, we developed a hand sanitizer composed of active ingredients - geranial, cineol, menthol, and Chamaecyparis obtusa - and performed a disinfection test, which targets 10 kinds of species (Alternaria citrimacularis, Alternaria consortialis, Aspergillus niger, Aspergillus versicolor, Cladosporium sphaerospermum, Coniothyrium aleurites, Penicillium brevicompactum, Penicillium corylophilum, Penicillium paneum, and Penicillium polonicum), of fungi investigated in museums and libraries. It was then confirmed to exhibit excellent disinfecting effects. Thus, this hand sanitizer is expected to prevent skin diseases and secondary infections in administrators dealing with cultural properties, archives, and books.

• Journal of the Korean Wood Science and Technology
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• v.42 no.6
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• pp.682-690
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• 2014

In order to improve the thermal stability of wood plastic composites (WPC), thermal degradation behavior of WPC in this study was investigated by the addition of wood flour and fire retardant after hybridization of wood flour and ammonium polyphosphate (APP) into polypropylene (PP) matrix. Thermal degradation behavior of all formulations was analyzed with thermogravimetric analyzer under nitrogen environment at heating rate of $10^{\circ}C/min$. As the thermal degradation temperature of wood flour is lower than that of PP, char layer formed by the wood flour decreases the speed of heat transfer to PP. In addition, the char layer increases the 2nd thermal degradation temperature and decreases the 2nd thermal degradation speed. The WPC treated with APP increases the 1st and 2nd degradation temperatures. In the case of WPC with high loading level of wood flour, the 1st thermal degradation temperature and 2nd thermal degradation rate were increased by the addition of APP, and then the amount of remnants at high temperature was increased by the increase of the APP loading level. In the case of WPC treated with APP, the amount of the remnants at high temperature was increased with the increase of wood flour content from 10 wt% to 50 wt%, indicating that char formation of the APP and wood flour occurred at the same time, resulting in high thermal stability effect by the increase of wood flour content.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.85-92
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• 1999

The complete catalytic oxidation of vinyl chloride was investigated over chromium oxide supported ${\gamma}$-alumina using a fixed bed micro-reactor at temperature between 240 and $300^{\circ}C$ and concentration between 600 and 3500 ppm. The oxidation of vinyl chloride was nonlinear in the concentration of vinyl chloride and zeroth order in the concentration of oxygen. The addition of HCl and $H_2O$ as products to the feed stream didn't influence the conversion of vinyl chloride. Several kinetic rate model were tested to describe the data over the range of condition investigated, and developed a model which provide the best correlation of experimental data. The resulting model of kinetic rate was derived by assuming that the reacting occurred via adsorption and subsequent decomposition of the vinyl chloride onto the oxygen covered chromium oxide surface, with the reaction being inhibited by the adsorption of vinyl chloride. The percent standard deviation between the predicted and experimental was about 5.2%, and the activation energy was 18.9 kcal/mol.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.52-62
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• 1991

The toxic effect of azalea extract, expecially on cardiovascular system, is relatively unclear. The purpose of this study is to study the possible underlying mechanism and effect of toxic ingredient of azalea on cardiovascular system. The 71 healthy rabbits were divided into 10 groups : In group as preliminary study ; 4cc of normal saline was administered intravenously(N) ; 0.7gm/kg and 1.0gm/kg of azalea extract was administered respectively in the same route, volume(A1, A2) ; atropine was administered intravenously(A) ; after pretreatment with atropine(0.04mg/kg) to block parasympathetic system, azalea extract was injected like the above groups(AA1, AA2) ; normal saline, 0.7gm/kg and 1.0gm/kg of azalea extract were administered respectively with 0.2cc(1 : 1000) epinephrine(E0,E1,E2). We measured the following indices at I minute interval during first 10 minutes and then 10 minute interval during next 30 minutes : RR interval, QTc interval, maximal systolic and diastolic pressure drop with occuring time and presence of significant arrhythmia. The results were as follows : 1. The changes of RR interval, QTc interval were significantly increased in groups by Azalea extract. The blood pressure change was significantly decreased in groups by Azalea extract. There were no significant differences according to dosage of Azalea extract. 2. The changes of RR interval, blood pressure were significant differences between administration of atropine and Azalea extract after pretreatment with atropine, but not in the change of QTc interval. 3. There were no significant differences in the change of RR interval, ATc interval, blood pressure drop according to pretreatment with atropine. 4. The interaction between epineprine and Azalea extract was not noted by the effect of epineprine itself. 5. The ST change by 0.7gm/kg, 1.0gm/kg of Azalea extract was revealed in 1 case(14.0%), 7 case(100%), respectively. 6. Most of all cases with arrhthymia, ventricular tachycardia, ventricular fibrillation, were noted in the group by epineprine, except one case by Azalea extract(1.0gm/kg). It was idioventricular rhythm. In conclusion, azalea extract has negative inotropic and chronotropic effect with arrhythmogenic potential possibly through direct myocardial ischemia or injury but we cann't be absolutely exclusive of actions of autonmic nervous system, especially parasympathetic nervous system.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.100-101
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• 2003

휘발성 유기 화합물(Volatile organic compounds, VOCs)은 산업공정에서 유기 용제로 사용되며 수송, 저장 및 취급시 대기로 쉽게 방출된다. 또한 자동차 배출가스, 소각로, 쓰레기 매립장, 폐수 처리시설 및 일반 가정에서의 각종 연소 과정에서도 유출된다. VOCs 의 유출은 그 자체가 인체에 유해할 뿐 아니라, 대기 중에 배출되어 질소 산화물과 함께 광화학 반응을 일으킴으로서 오존 또는 알데히드와 같은 2차 오염물질을 생성시켜 오존층 파괴 및 지구 온난화, 산성비 등으로 지구 환경에 악영향을 초래하고 있다. (중략)

• Journal of the Korean Applied Science and Technology
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• v.35 no.2
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• pp.350-356
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• 2018

Hydroxyapatite has been used for biomaterials since it has high biocompatibility. In this study, c-plane oriented hydroxyapatite was synthesized by hydrolysis of dicalcium phosphate intermediate by controlling temperature, concentration and pH. In basic condition, rod-like hydroxyapatite crystals were aggregated to form irregular particles in low concentration and plate-like particles exposed c-plane of hydroxyapatite crystal were obtained in high concentration, causing difference of 3 mV in zeta potential. Physicochemical properties of product were characterized by XRD, SEM, FT-IR, zeta potential measurement.

• Proceedings of the Microbiological Society of Korea Conference
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• 1991.04a
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• pp.187-199
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• 1991

Penicillium verruculosum 배양액으로부터 소단위체 분자량이 60,000(cellobiohydrolase I)과 66,000(cellobiohydrolase II) 및 76,000(cellobiohydrolase III)인 cellobiohydrolase를 분리 정제하여 그들의 일반적 특성을 검토하였다. 이들 세 효소들은 모두 당단백질로서 cellobiohydrolase I, II 그리고 III는 각각 $8.6\%$, $4.2\%$ 그리고 $8.5\%$의 당함량을 나타냈으며 세 효소 모두 pH 4.5 - 5.0, 온도 $50 - 60^{\circ}C$에서 최적조건을 나타냈다. Cellobiohydrolase I, II 및 III는 모두 Avicel, cotton, 여지 등의 결정성 섬유소 뿐만 아니라 carboxymethyl cellulose에도 활성도를 나타냈다. 정제된 cellobiohydrolase I, II 및 III의 Avicel에 대한 비 활성도는 각각 0.07, 0.10, 그리고 0.07 unit per mg. of protein 이었으며 Avicel 분해 생성물은 거의 cellobiose였다. 또한 p-Nitrophenyl-$\beta$-D-cellobioside를 기질로 하였을 때 이들 세 효소 모두 포도당에 의해 활성도가 저해되지 않은 반면 cellobiose에 의해서는 저해되었다. 아미노산조성, 트립신에 의한 펩타이드들의 용출양상 그리고 항체를 이용한 Immunoblotting 결과로부터 cellobiohydrolase II와 III는 동일 유전자산물이거나 1차 구조가 거의 유사한 단백질로 추정된다. Cellobiohydrolase II로부터 분리한 2 개의 펩타이드의 아미노산 서열은 Trichoderma cellobiohydrolase I과 상동성을 보였으며 또한 이 두 호소의 아미노산조성은 매우 유사하였다.