• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.11 s.254
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• pp.1123-1130
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• 2006

This study discusses about research efforts of hydrogen generation from hydrocarbon(e.g., diesel, gasoline, natural gas, and LPG), especially, butane reforming by using Autothermal Reforming Reaction (ATR) technology. Several catalysts were selected for butane ATR. Thermodynamic reactor conditions (temperature, $O_2$/C, S/C) are varied and reforming characteristics of 2 catalysts (Pt and Rh on ceramic supports) and 1 commercial catalyst (FCR-HC35) have been examined. To understand reaction behaviors in an ATR reactor comprehensively, temperature profiles of reactor were observed. By mass transfer limitation, fuel conversion decreases when GHSV increases. Significant temperature variation along the reactor was observed and it was mainly due reaction kinetics difference between exothermic oxidation and endothermic reforming reaction.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.300-304
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• 2003

수용성 안료인 RhB를 대상으로 GF/C에 고정한 $TiO_2$와 유동층 반응기를 이용하여 제거실험을 수행한 결과 다음과 같은 결론을 얻었다. 1. 고정화 $TiO_2$의 경우도 분말을 이용한 것과 같이 최적 광촉매 투입량이 나타났으며, 최적 투입량은 40.0 g/L이었고, 분말 $TiO_2$를 이용하는 광촉매 반응의 초기속도식과 같이 Langmuir - Hinshelwood 식으로 표현될 수 있었다. 분말 $TiO_2$를 이용한 경우보다 초기반응속도는 2.3배 느렸으나, 고정화 $TiO_2$의 경우 연속공정이 가능하고 촉매회수 공정이 필요하지 않으므로 반응속도만 더 높일 수 있으면 현장적용 가능성이 높다고 사료되었다. 2. 고정화 $TiO_2$의 최소유동을 위한 공기 공급량은 4 L/min, 최대 반응속도는 5 L/min에서 나타나 고정화 $TiO_2$를 충진한 유동층 반응기의 최적 공기 공급량은 최소유동화 속도 부근인 것으로 사료되었다.

• Journal of Magnetics
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• v.21 no.2
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• pp.179-182
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• 2016

In this paper, 10 nm $Fe_3O_4$ nanoparticles were modified on the surface of $2{\mu}m$ flower-like bismuth oxychloride (BiOCl) spheres by a facile co-precipitation method. The results showed that the $Fe_3O_4/BiOCl$ nanocomposites exhibited excellent photocatalytic activity and superparamagnetic property ($M_s=3.22emu/g$) under visible light for Rhodamine B (RhB) degradation. Moreover, the $Fe_3O_4-BiOCl$ photocatalyst possessed magnetic recyclable property, which could maintain high photocatalytic effective even after 20 cycle times. These characteristic indicates a promising application for wastewater treatment.

• Nutrition Research and Practice
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• v.8 no.5
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• pp.501-508
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• 2014

BACKGROUND/OBJECTIVES: Rubus Coreanus Miquel (RCM), used as a traditional Korean medicine, reduces chronic inflammatory diseases such as cancer and rheumatoid arthritis. However, its mechanism has not been elucidated. In this study, we examine the anti-inflammatory effects of RCM and their possible mechanisms using RAW 264.7 cells. MATERIALS/METHODS: Unripe RCM ethanol extract (UE), unripe RCM water extract (UH), ripe RCM ethanol extract (RE), and ripe RCM water extract (RH) were prepared. Inflammatory response was induced with LPS treatment, and expression of pro-inflammatory mediators (iNOS, COX-2, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6) and NO and $PGE_2$ productions were assessed. To determine the anti-inflammatory mechanism of RCM, we measured NF-${\kappa}B$ and MAPK activities. RESULTS: UE and UH treatment significantly reduced NF-${\kappa}B$ activation and JNK and p38 phosphorylation and reduced transcriptional activities decreased iNOS, COX-2, and pro-inflammatory cytokines expressions, and NO and $PGE_2$ productions. RE and RH treatments reduced IL-$1{\beta}$ and IL-6 expressions through suppressions of JNK and p38 phosphorylation. CONCLUSIONS: In this study, we showed that RCM had anti-inflammatory effects by suppression of pro-inflammatory mediator expressions. Especially, unripe RCM showed strong anti-inflammatory effects through suppression of NF-${\kappa}B$ and MAPK activation. These findings suggest that unripe RCM might be used as a potential functional material to reduce chronic inflammatory responses.

• Clean Technology
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• v.23 no.2
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• pp.196-204
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• 2017

CdZnS/ZnO composite was prepared through low-temperature precipitation and drying method. The property of CdZnS/ZnO as a recyclable photocatalyst for the degradation of rhodamine B (RhB) under visible light irradiation was examined. The sample was characterized by XRD, FE-SEM, XPS, UV-vis DRS and photoluminescence techniques before and after repeated reaction to investigate the change of properties during the photocatalytic reaction. During repeated reaction, the CdZnS/ZnO showed an improved photocatalytic activity and recycle stability. Among two feasible reaction pathways for photocatalytic degradation of RhB, the cleavage of conjugated chromophore was found to predominate over N-dealkylation of chromophore skeleton in the present work. The results indicate that the CdZnS/ZnO, prepared by a simple precipitation method, can be used as a visible-light driven photocatalyst with enhanced cycle stability and activity.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.2
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• pp.153-162
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• 2002

Earlier breeding experiments undertaken at Central Sericultural Research and Training Institute, Mysore, India since a decade had resulted in the development of many productive and qualitatively superior bivoltine hybrids. However, the hot climatic conditions of tropics prevailing particularly in summer are not conducive to rear these high yielding bivoltine hybrids. This has necessitated breeding of compatible bivoltine hybrids for year-round rearing. Accordingly, the Japanese hybrid, B2Ol ${\times}$ BCS12 which was found to be tolerant to high temperature was used as breeding resource material. Following hybridization and selection rearing of silkworms was taken up in SERICATRON (Environmental chamber with precise and automatic control facilities for uniform maintenance of temperature and humidity) at high temperature of $36{\times}1^{\circ}C$ and 85${\times}$5% RH in fifth instar and the control batches at $25{\times}1^{\circ}C$ and 65{\times}$5% RH. Directional selection was resorted to the batches reared at 36$\pm$1$^{\circ}C$ till F$_{5}$ keeping pupation rate as important selection criteria. From $F_{2}% onwards the experiment was modified in such a way as to conduct normal rearing every alternate generation to regain the lost vitality due to continuous exposure to high temperature and high humidity stress. At $F_{2}$ , Oval and dumb-bell cocoons were separated out and designated as CSR18 and CSR19, respectively. By utilizing these lines at $F_{12}$, the hybrid CSR18$\times$CSR19 was prepared and studied for the thermotolerance by subjecting to stress condition at high temperature of 36$\pm$1$^{\circ}C$ and 85$\pm$5% RH in fifth instar and the control batches at $25{\times}1^{\circ}C$ and 65${\times}$5% RH. The better performance of CSR18${\times}$CSR19 (survival > 88%) at $36{\times}1^{\circ}C$ clearly indicates the general superiority of CSR18${\times}$CSR19 with regard to high temperature tolerance over the productive hybrids and CSR18$\times$CSR19 can perform well in varied agro-climatic conditions of the tropics with optimum qualitative and quantitative characteristics.s.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.102.2-103
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• 2003

This studies were investigated the occurrence of Sclerotinia rot by Sclerotinia Sclerotiorum at the lettuce field in Uiryeong-Gun, Gyeongsangnam-Do and were isolated the most effective microorganism for the biological control to the pathogen, S. sclerotiorum YR-1 strain from diseased soil and lettuce leaves. For the pathogenicity test, the most suitable inoculmn density of YR-1 strain was selected as the mycelial suspension of 40m1 showing disease incidence of 80％, and the symptom showed as same as at the fields, the leaves and stem had rotten and developed white downy mycelial at the diseased lesion on the leaves and stems, and produced black and irregular sclerotinia. On the PDA dual test, about 300 isolates were examined the antifungal activity to the pathogen, YR-1 strain, and among them, A-2, A-7, and RH-4 strain were selected most effective antagonistic bacteria. At pots test, the control value of A-7 strain showed the highest value as 85％ which was more effective than that of others in a growth chamber. For the promotion of control effect, the selected 3 isolates were spayed on the lettuce leaves as a sole and/or mixed treatments in a growth chamber, the mixed treatment of A-7 and RH-4 strain showing the control value of 90％ was most effective than that of sole treatment with A-7 or RH-4 strain showing the control value of 80％, respectively and mixed treatment with A-2 and A-7 strain and A-2, A-7 and RH-4 strain. In addition, 3 bacteria re-isolated from diseased soils, and all of the selected 6 isolates investigated the control effect at pots in a growth chamber, According to the results, A-7 and Pro-EB 15 strain showed the control value of 91.0％ and 90.1％ respectively, and they were selected most effectual antagonistic bacteria to control lettuce sclerotinia rot and identified as the Bacillus mojanuinensis by 16s RNA analysis. This is the first report on the biological control using by B. mojanvinensis to the lettuce Sclerotinia rot.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.644-651
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• 2007

To establish the optimum conditions for storing buttercup squash, we examined the effectiveness of several storage methods and the quality of the squash under various storage conditions, including temperature (12 and $20^{\circ}C$) and relative humidity (20, 40, 60, and 80%). The spoiling rate of the squash was affected more by the storage temperature than the relative humidity, and the squash stored at $20^{\circ}C$ started to be deteriorated after 20 days of storage. At $20^{\circ}C$, soluble solid content gradually increased until 20 days of storage, and then it tended to decrease. The L-value had a tendency to increase with days of storage, and the a- and b-value also increased after 40 days. In addition, the color changes were great when the squash was stored at high temperature and high relative humidity. The total pectin content increased until 20 days at $20^{\circ}C$, and then it decreased, but less change was observed in the squash stored at $12^{\circ}C$. Overall, the results showed that storage at $20^{\circ}C$ after field curing resulted in excessive weight loss, color loss and poor eating quality, as well as a high level of decay (approximately 70%) after 40 days. However, the squash stored at $12^{\circ}C$ and 60% RH (relative humidity) showed less degreening and had a reduced level of decay, below 10%.

• Proceedings of the Plant Resources Society of Korea Conference
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• 1999.10a
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• pp.46-57
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• 1999

Ginseng(Panax ginseng C.A. Meyer) is important medicinal plant but requires 4-year cultivation for root harvest because of slow growth. In contrast, ginseng callus and hairy roots grow vigorously and may Produce the same or more biologically active compounds for human health than natural ginseng roots. Therefore, ginseng callus and hairy roots can be used for commercial purposes. Polyacetylene, one of anti-cancer compounds in ginseng, was not detected in the callus cultured on the medium containing 2, 4-B, but cells derived from the callus growth was excellent, The ginseng calli cultured on the medium containing 2mg11 CPA and 0.05mg/1 BA was grown vigorously and produced panaxydol, one of ginseng polyacetylene. The biosynthesis of polyacetylene in callus was not affected by addition of NAA and sucrose in media. The SH medium was better than the MS medium for ginseng callus growth and biosynthesis of panaxydol. Another ginseng anti-cancer compounds, ginsenoside-Rg$_3$, Rh$_1$and Rh$_2$ were detected in ginseng hairy roots by heat treatment. Those of Panax ginseng were obtained after root disks of three-year old roots were infected with Agrobacterium rhizogenes Rl000 $A_4$T in dark condition after one month of culture. The optimum growth of hairy roots was achieved in the culture of 1/2 MS liquid medium in dark(22$^{\circ}C$) under 60 rpm gyratory shaking. Hairy roots grew well in 5 ι Erlenmeyer flasks, 1ι roller drums, 10ι jar-fermenters, and especially in 20ι air-lift .culture vessels. All heat treatments had remarkably different ginsenoside contents. Eleven ginsenosides were determined in heat treatment, eight in freeze dried hairy roots. Contents of ginsenoside-Rbl , Rb2, Rc, Rd. Re, Rf, and Rg$_1$tested in all heat treatments were less than those of freeze dried hairy roots. Contents of glnsenoside-Rg$_2$ in heat treatment for 1 hour at 105$^{\circ}C$ was 4.92mg/g dry wt, 3.9 times higher than 1.27 mg/g dry wt of freeze dried hairy roots. The optimum condition of heat treatment for the production of ginsenoside-Rg$_3$and Rhl was 2 hours at 105$^{\circ}C$, and ginsenoside content was 2.58mg/g dry wt and 3.62mg/g dry wt, respectively. The production of ginsenoside-Rh2 was the highest in heat treatment for 2 hours at 105$^{\circ}C$ among treatments examined, and ginsenoside-Rh$_2$content was 1.08mg/g dry wt.

• Journal of Environmental Impact Assessment
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• v.13 no.4
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• pp.197-211
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• 2004

Visibility impairment was known as an indicator of the increased air pollution. In many previous studies, it is known that both directly emitted fine particles mainly from vehicles and secondary aerosols from photochemical reactions could contribute to this visibility impairment in addition to the meteorological condition. Furthermore, the visibility showed different change patterns according to the geographical condition. In order to research into the influence of these factors on visibility, this study analyzed the visibility at 15:00, observed from 1990 to 2001 in Seoul, Ganghwa, Susan, Gwangju, Jeju. As a result, the visibility was increased in Seoul except the rainfall period, but in Susan, Gwangju, Jeju, it decreased with the relative humidity (RH). Especially, in Seoul, the number of low visibility days was larger than other sites and variations of the visibility were sensitive to the concentration of air pollutants, such as TSP, $NO_2$, $O_3$. The visibility impairment was mainly observed in meteorological condition of RH<50% and relatively stationary front. Therefore it is inferred that photochemical smog could lead to the low visibility in Seoul. On the other hands, in Ganghwa and Susan, when RH was 60~70%, the low visibility observed under the influence of the transports of air pollutants from nearby cities as well as humid air mass from coastal region. And in Jeju, sea fog and humid air mass caused the visibility impairment when the RH was larger than 80%. Finally, during the observational period, some cases of low visibility phenomena were simultaneously observed in the vast region including Seoul, Susan, Ganghwa. It not only includes the visibility aggravation by Asian Dust, but also could be caused by the movement and diffusion of flying dust or secondary aerosols. Moreover, the result shows that these phenomena could be mainly influenced by meteorological factors covering the wide regions.