• Journal of Korean Society of Environmental Engineers
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• v.34 no.7
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• pp.445-453
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• 2012

An investigation for removal of 1-indanone (1-ID), which were commonly produced from the biological and/or chemical treatment and natural weathering of the PAHs-contaminated soils, via oxidative transformation mediated by birnessite in the presence of various phenolic mediators is described. This study also examines the potential effect of the natural occurring substance humic acid (HA) on the oxidative transformation. The experiment was carried out in aqueous phase as a batch test (10 mg/L 1-ID, 0.3 mM phenolic mediators, $1.0g/L\;{\delta}-MnO_2$, at pH 5). All of the 11 tested phenoilic mediators belong to the group of natural occurring phenols and are widely used as model constituents of humic substances. From the results of HPLC analysis, it is demonstrated that 1-ID was not reactive to birnessite itself, but it can be effectively removed in birnessite-mediated cross coupling reactions in the presence of the phenolic mediators. The percent removals of 1-ID after 2 day incubation were ranged from 9.2 to 71.2% depending on the phenolic mediators applied. The initial rate constant ($K_{int}$, $hr^{-1}$) values for the 1-ID removals obtained from the pseudo-first-order kinetic plots also widely ranged from 0.18 to 15.0. Results of the correlative analysis between the removal efficiencies and structural characteristics of phenolic mediators indicate that the transformation of the 1-ID was considerably enhanced by the addition of electron-donating substituents (e.g., -OH, $-OCH_3$) at the benzne ring, and much less enhanced by the addition of electron-withdrawing substituents (e.g., -COOH, -CHO). The presence of HA showed that removal efficiencies of 1-ID in the birnessite-phenolic mediator systems decreased with increasing HA concentrations. However at low concentration of HA (< 2 mg/L), it caused some enhancement in the removals of 1-ID as compared to the control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.393-407
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• 1997

A survey of biological and chemical characteristics in the middle-northern East Sea of Korea was carried out at 28 stations in October, 1995 on board R/V Tam-Yang. On the basis of the vertical profiles of temperature, salinity and dissolved oxygen, water masses in the study area were divided into 5 major groups; (1) Low Saline Surface Water (LSSW), (2) Tsushima Surface Water (TSW), (3) Tsushima Middle Water (TMW), (4) North Korean Cold Water (NKCW), (5) last Sea Porper Water (ESPW). Other 4 mixed water masses were also observed. It is highly possible that the LSSW which occured at depths of $0\~30m$ in the most southern part of the study area is originated from the Yangtze River (Kiang) of China due to very low salinity $(<32.0\%_{\circ})$ relatively high concentration of dissolved silicate and no sources of freshwater input into that area. Oxygen maximum layer in the vertical profile was located near surface at northern cold waters and became deeper at the warm southern area. Oxygen minimum layer af depths $50\~100m$, which is TMW, were found in only southern area. In the vortical profiles of nutrients, the concentrations were very low in the surface layer and increased drammatically near the thermocline. The highest concentration occurred in the ESPW. The relatively low value of Si/P ratio in the ESPW (13.63) compared to other reports in the East Sea was due to continuous increase of P with depth as well as Si. The N : P ratio was about 6.92, showing that nitrogenous nutrient is the limiting factor for phytoplankton growth. The exponential relationship between Si and P, compared to the linear relationship between N and P, indicates that nitrate and phosphate have approximately the same regenerative pattern, but silicate has delayed regenerative pattern.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.3
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• pp.203-213
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• 1991

Zooplankton samples were collected vertically from different layers with a closing net at 14 stations in the middle East Sea of Korea in February, August and September to study distribution of biological indicators for analysis of water masses. Horizontal and vertical distributions of important species of copepods and chaetognathas known as indicator species were closely related to distributions of different water masses and oceanic fronts. Pleuromamma gracilis, Calanus tenuicornis, Sagitta enflata and Sagitta minima were found to be reliable indicator species to determine warm water mass with warm core, and Calanus cristatus, Calanus tonsus and Sagitta elegans could be used as cold water species for evaluating the movement of cold current from North Korea, and Gaetanus armiger was deep sea water species. Therefore, it was found that North Korean Cold Current down to the south along the coast appeared to be significant in the surface around Chumunjin area, and from here towards the south the cold water containing S. elegans submerged under warm water with S. enflata which were about $2{\~}4^{\circ}C$ higher than that of the vicinity and reappeared near Chukpeon area in surface layer. In the layer between loom and 300m depths, distribution of Pleuromamma gracilis and Sagitta bedoti indicated that warm water mass and front zone influenced by the different water systems were formed in northwestern area off Ulreung-do. In $300{\~}500m$ layer, the proper cold water could be estimated to be present in the northwestern area off Ulreung-do throughout the survey period by the high abundance of Gaetanus armiger. In August, distributions of S. bedoti, S. enflata and S. minima were valuable index to find oceanic fronts and warm core.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.277-287
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• 2010

Several species of the genus Aphidius are used in biological control programs against aphid pests throughout the world and their behavior and physiology are well studied. While the importance of sensory organs in their behavior is understood, their antennal structure remains largely unknown. In this study, the external morphology and distribution of the antennal sensilla on the antennal of both female and male adults of A. colemani were described using scanning electron microscopy (SEM). Generally, the filiform antennae of males ($l,515.2{\pm}116.5\;{\mu}m$) are longer than females ($l,275.1{\pm}103.4\;{\mu}m$). Antennae of this species are made up of radicle, scape, pedicel and flagellomeres. Male and female antennae differed in the total number of flagellomeres as 15 in males and 13 in females. The result of SEM observation was characterization and grouping of seven types of receptors into morphological classcs: Bohm bristles, Sensilla placodea, 2 types of S. coeloconica and S. trichodea, and S. basiconica as with a tip pore and with wall pores. In addition, the possible functions of the above sensilla types arc discussed in light of previously published literature; mechanoreception (Bohm bristles, S, coeloconica I & II and S. trichodea) and chemoreception (S. placodea, S. basiconica type I & II).

• Korean journal of applied entomology
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• v.47 no.2
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• pp.133-139
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• 2008

This study was performed to investigate the immature development period, fecundity, emergence rate and sex ratio of Sclerodermus harmandi against different host insects, Monochamus alternatus, M. saltuarius and Psacothea hilaris. Full grown larvae and pupae of host insects were provided with foods. The mean larval period of S. harmandi female was $29.2{\pm}0.93\;and\;25.1{\pm}0.47$ days in larvae and pupae of M. alternatus, $27.1{\pm}0.41\;and\;26.0{\pm}0.69$ days in M. saltuarius, and $26.3{\pm}0.38\;and\;31.2{\pm}0.24$ days in P. hilaris, respectively. S. hilaris adults were emerged at $12.9{\pm}0.2$ days in female and $11.9{\pm}0.2$ days in male after pupation when hosted M. alternatus pupa. Development period in male showed shorter one day than in female. Success rate of oviposition against different hosts was higher as 98.6 and 97.5% on full grown larva and pupa of M saltuarius. Emergence rate was higher as 90.1 and 87.3% on M. saltuarius larvae and pupae. Sex ratio of emerged S. harmandi adults was approximately 10:1 (Female : Male), females showed higher emergence rate than males. The period until first oviposition after emergence in S. harmandi female was the shortest in $4.6{\pm}0.1$ days on M. saltuarius pupa. When three females of S. harmandi were inoculated on M. saltuarius larva, the number of laid eggs was the highest $62.7{\pm}2.5$ per female.

• Food Science and Preservation
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• v.21 no.4
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• pp.587-592
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• 2014

Brassica spp. vegetables have been known to have biological activities such as anti-cancer and anti-inflammatory activities. In this study, we investigated the in vitro physicochemical characteristics and antioxidant activities of commonly used Brassica spp. sprout vegetables such as kohlabi (Brassica oleracea var. gongyloides), red radish (Raphanussativus L. var. sativus), broccoli (B. oleracea var. italica), cabbage (B. rapavar. glabra Regel), rape (B. napus), radish (R. sativus), and tatsoi (B. campestris var. narinosa) sprouts. Our results showed that the vegetables with the highest total phenolics contents were the radish sprout ($24.40{\pm}1.24mg\;TAE/g$) and kohlabi sprout extracts ($23.97{\pm}0.46mg\;TAE/g$). Furthermore, the vegetable with the highest total flavonoid content was the radish sprout extract ($15.30{\pm}1.35mg\;CE/g$). However, the kohlabi sprout extract showed the highest DPPH radical scavenging value ($IC_{50}=1.95mg/mL$) and ORAC value (79.03 mM TE/g). In addition,the six kinds of Brassica spp. sprout vegetable extracts, except tatsoi, significantly inhibited the reactive oxygen species (ROS) production and showed that intracellular oxidative stress is closely related tothe accumulation of differentiated adipocytes and fat during the adipogenesis of 3T3-L1 preadipocytes. These results suggest that Brassica spp. sprout vegetables, especially kohlabi and radish sprout extracts, can be used to develop natural antioxidants.

• Korean Journal of Agricultural Science
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• v.27 no.1
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• pp.25-32
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• 2000

This experiment was conducted to investigate the effect of feeding monensin on the growth performance and ruminal fermentation characteristics of Han-Woo cattle. Seventy two uncastrated Han-Woo male cattle(BW 267 kg) were randomly allotted to 0, 22, and 33 ppm monensin treatments, three replicates per treatment and eight heads per replicate. Animals were kept in an open barn for an 140-d feeding trial, Concentrates containing different levels of monensin and rice straw cut in 15cm length were fed ad libitum separately. The results obtained from this study were summarized as follows. 1. No significant difference was found in daily gain by monensin feeding. 2. Monensin did not affect the total feed (concentrate + roughage) intake: however, as the monensin level increased, the total feed intake tended to decrease, resulting in 5 % reduction in 33 ppm monensin treatment. 3. Although no significant difference was found among three treatments, 22 and 33 ppm monensin improved the feed efficiency(total feed/gain) by 5.2 % and 5.1 %, respectively, as compared to the 0 ppm monensin treatment. 4. Monensin did not affect the concentrations of ruminal total VFA and acetic acid consistently. Although not significant, monensin feeding of 22 and 33 ppm caused marked increase in ruminal propionic acid concentration, 13.8 % and 19.3 %, respectively. Ruminal butyric acid concentration decreased as monensin level increased. Monensin feeding, regardless of level, decreased the A/P ratio by 12.5 %. In conclusiuon, monensin feeding increased the propionic acid concentration, and decreased the butyric acid concentration and A/P ratio in the rumen. Animals fed monensin consumed less feed, causing the improvement in feed efficiency. Thus, monensin appeared to be a useful feed additive, directing the rumen fermentation in a more productive way. Feed efficiency improved similarly both in 22 and 33 ppm monensin treatments, indicating that 22 ppm might be good enough rather than the 33 ppm monensin level.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.1
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• pp.94-131
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• 2007

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2004 and 2005 has been done. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD and flow visualization(PIV, PTV and LDV methods) technologies were widely applied for developing facilities and their systems. (2) The research trends of the previous two yews are surveyed as groups of natural convection, forced convection, electronic cooling, heat transfer enhancement, frosting and defrosting, thermal properties, etc. New research topics introduced include natural convection heat transfer enhancement using nanofluid, supercritical cooling performance or oil miscibility of $CO_2$, enthalpy heat exchanger for heat recovery, heat transfer enhancement in a plate heat exchanger using fluid resonance. (3) The literature for the last two years($2004{\sim}2005$) is reviewed in the areas of heat pump, ice and water storage, cycle analysis and reused energy including geothermal, solar and unused energy). The research on cycle analysis and experiments for $CO_2$ was extensively carried out to replace the Ozone depleting and global warming refrigerants such as HFC and HCFC refrigerants. From the year of 2005, the Gas Engine Heat Pump(GHP) has been paid attention from the viewpoint of the gas cooling application. The heat pipe was focused on the performance improvement by the parametric analysis and the heat recovery applications. The storage systems were studied on the performance enhancement of the storage tank and cost analysis for heating and cooling applications. In the area of unused energy, the hybrid systems were extensively introduced and the life cycle cost analysis(LCCA) for the unused energy systems was also intensively carried out. (4) Recent studies of various refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and of alternative refrigerants including carbon dioxide. Efficiency of various compressors and expansion devices are also dealt with for better modeling and, in particular, performance improvement. Thermoelectric module and cooling systems are analyzed theoretically and experimentally. (5) According to the review of recent studies on ventilation systems, an appropriate ventilation systems including machenical and natural are required to satisfied the level of IAQ. Also, an recent studies on air-conditioning and absorption refrigeration systems, it has mainly focused on distribution and dehumidification of indoor air to improve the performance were carried out. (6) Based on a review of recent studies on indoor environment and building service systems, it is noticed that research issues have mainly focused on optimal thermal comfort, improvement of indoor air Quality and many innovative systems such as air-barrier type perimeter-less system with UFAC, radiant floor heating and cooling system and etc. New approaches are highlighted for improving indoor environmental condition as well as minimizing energy consumption, various activities of building control and operation strategy and energy performance analysis for economic evaluation.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.2
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• pp.153-165
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• 2014

Carbon dioxide capture and storage (CCS) technology is recognizing one of method responding the climate change with reduction of carbon dioxide in atmosphere. In Korea, due to its geological characteristics, sub-seabed geological $CO_2$ storage is regarded as more practical approach than on-land storage under the goal of its deployment. However, concerns on potential $CO_2$ leakage and relevant acidification issue in the marine environment can be an important subject in recently increasing sub-seabed geological $CO_2$ storage sites. In the present study effect data from literatures were collected in order to conduct an effect assessment of elevated $CO_2$ levels in marine environments using a species sensitivity distribution (SSD) various marine organisms such as microbe, crustacean, echinoderm, mollusc and fish. Results from literatures using domestic species were compared to those from foreign literatures to evaluate the reliability of the effect levels of each biological group and end-point. Ecological effect guidelines through estimating level of pH variation (${\delta}pH$) to adversely affect 5 and 50% of tested organisms, HC5 and HC50, were determined using SSD of marine organisms exposed to the $CO_2$-induced acidification. Estimated HC5 as ${\delta}pH$ of 0.137 can be used as only interim quality guideline possibly with adequate assessment factor. In the future, the current interim guideline as HC5 of ${\delta}pH$ in this study will look forward to compensate with supplement of ecotoxicological data reflecting various trophic levels and indigenous species.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.43-52
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• 2000

Deodorization characteristics and removal rate of sulfur-containing odor have been investigated in the soil filter reactors packed with montmorillonites (Mont.), rice hulls(Rh.), and thickening-activated sludge(Ts.). And variation of pH and $SO_4{^{2-}}$ with the removal of malodorous sulfur compounds have been investigated together. As compared removal rate of montmorillonites between wet and dry condition for sulfur compounds through batch test, it showed that wet condition was better than dry one; removal ratio, as wet/dry, was $H_2S$ of 1.2 and $CH_3SH$ of 1.9, and decrease of pH and increase of $SO_4{^{2-}}$ concentration in the wet condition also showed to be larger than in dry condition. In continuous test for biological deodorization experiment, removal rate of sulfur compounds in reactor packed with Mont., Rh. and Ts, was more than 98 %, and the variation of static pressure was maintained stably under condition of SV $150h^{-1}$, LV 4.2 mm/sec and SV $200h^{-1}$, LV 5.6 mm/sec, and in reactor packed with Mont. and Rh., $H_2S$ was 76.4 % to 87.2 % and $CH_3SH$ was 87.8 % to 93.3 % under the same condition. From above results, it ascertained that it can obtain the high deodorization efficiency by inoculating thickening-activated sludge in soil filter using montmorillonites.