• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.4
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• pp.56-64
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• 2000

Behavior of trace metals in Masan Bay, Korea was studied in August 1998 when the oxygen deficient condition occurred. Dissolved Cd and Zn concentration in the surface waters decreased with increasing distance from Masan Harbor. Dissolved concentrations of Cd, Cu Pb and Zn in the surface waters were higher than bottom waters. Particulate(acid-teachable fraction) concentrations of Cu, Cd and Pb in the surface waters of Masan Bay decreased with increasing distance from Masan Harbor. Bottom waters contained higher concentrations of particulate Cd, Cu, Pb and Zn than surface waters. Distribution coefficients between dissolved and particulate phase (K/sub d/) of Cu and Cd decreased with the increasing distance from the Harbor, possibly due to reaction of these elements with sewage-derived particulate matter Al, Zn, Cu, Cd, and Pb in the surface sediment showed relatively high concentration in the inner Masan Bay.

• Journal of Animal Science and Technology
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• v.44 no.5
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• pp.625-632
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• 2002

Livestock farmers face several limitations when using the government recommended sorghum cultivars for forage because of the limited seed supply. Therefore, the objective of the this study is to evaluate, select, and recommend the best high-yielding hybrid as the government recommended cultivars. The agronomic characteristics and forage yield of three cultivars (cv. P947, cv. KF429 and cv. SS405) of forage sorghum were evaluated at two locations (Suwon and Sunghwan) for 2 years (1999${\sim}$2000). 'KF429' was susceptible to foliar disease, while 'SS405' had less lodging resistance among the sorghum cultivars tested. When compared with 'P947' (recommended cultivar), dry matter yield of 'KF429' and 'SS405' cultivars increased by 16% and 75%, respectively. The crude protein of 'P947'(9.4%) was higher than other cultivars. The percentage of ADF and NDF were the lowest in 'KF429' cultivar. The results of forage performance experiment indicate that 'KF429' and 'SS405' are recommended as the government recommended sorghum cultivars due to a high lodging tolerance, disease resistance, and high dry matter yield.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1249-1254
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• 2005

The aim of this study was to determine the effect of maturity stage on the nutritive value of wild mustard straw in terms of chemical composition, in situ, in vitro dry matter degradability and calculated ME. The nutritive values of wild mustard, Sinapsis arvensis hays harvested at three stages were evaluated by chemical composition, in vitro gas production and in situ dry matter degradation methods. Gas production or dry matter (DM) degradation were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h and their kinetics were described using the equation p = a+b(1-e$^{-ct}$). Maturity had a significant effect on both the chemical composition and degradability of wild mustard. Neutral detergent fibre (NDF) and acid detergent fibre (ADF) (p<0.001) increased with increasing maturity whereas the crude protein (CP) (p<0.001) decreased. The gas produced after 96 h incubation ranged between 64.7 and 81.5 ml per 0.200 g of dry matter. The gas production (ml) at all incubation times and estimated parameters decreased with increasing maturity of wild mustard. The gas production at all incubation times and estimated parameters (a, b (a+b), metabolizable energy (ME) and organic matter digestibility (OMD)) were negatively correlated with NDF and ADF. The DM disappearance after 96 h incubation ranged between 50.8 and 76.1%. The in situ DM disappearance at all incubation times and estimated parameters decreased with increasing maturity of wild mustard. The in situ dry matter disappearance at all incubation times and some estimated parameters (c, a, b and effective dry matter degradability (EDMD)) were negatively correlated with NDF and ADF but positively correlated with CP. The nutritive value of wild mustard continually changed as it matured. Wild mustard, harvested at the proper stage of maturity offers considerable potential as a high quality forage for ruminants during the winter feeding period. The present study showed that if higher quality forage is an objective, wild mustard should be harvested at the early flowering stage.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.70-76
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• 2003

Three experiments were conducted to determine the effects of a sorghum-specific enzyme system, derived from an Aspergillus niger and Bacillus subtilis fermentation extract (carbohydrase activity of 1,650 $\alpha$-amylase units and cellulase activity of 30 fibrinolytic units/mL), on growth performance of finishing pigs. In Exp. 1,192 pigs (average initial BW of 46.1 kg) were fed sorghum-based diets without or with 360 mL of enzyme system per ton of sorghum in a 78 d growth assay. For d 0 to 39, gain/feed was improved (p<0.03) with enzyme supplementation, but ADG was not affected (p>0.15). For d 39 to 78 and overall (d 0 to 78), ADG, gain/feed, and digestibilities of DM and N were not affected (p>0.13) by enzyme supplementation. Backfat thickness, fat-free lean index, and scores for stomach keratinization and ulcers also were not affected (p>0.15) by the dietary treatments. In Exp. 2,168 pigs (average initial BW of 58.4 kg) were fed diets without or with 150, 300, or 450 mL/ton of the same enzyme system used in Exp. 1. Adding as much as 450 mL enzyme system / ton of sorghum did not affect (p>0.15) ADG or gain/feed for d 0 to 29 of the growth assay. However, during d 29 to 63, ADG increased by 11% (linear effect, p<0.02) and gain/feed increased by 10% (linear effect, p<0.06) as enzyme concentration was increased from none to 450 mL/ton of sorghum. For the overall period (d 0 to 63), ADG tended to increase (p<0.08) with enzyme supplementation, but gain/feed and digestibilities of DM and N were not affected (p>0.14). Carcass characteristics (dressing percentage, backfat thickness, and fat free lean index) also were not affected (p>0.20) by addition of the enzyme system. In Exp. 3,176 pigs (average initial BW of 46.7 kg) were fed diets without or with 450, 900, or 1,350 mL/ton of the same enzyme system used in Exp. 1 and 2 in a 71 d growth assay. Adding up to 1,350 mL/ton of enzyme had no effects (p>0.15) on ADG, gain/feed, digestibilities of DM and N, and carcass characteristics (dressing percentage, backfat thickness, and fat-free lean index). In conclusion, finishing pigs fed diets with a sorghum-specific enzyme system showed some positive trends for improved growth performance, but those effects were not large and (or) consistent.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.417-427
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• 2000

The substrate metabolism and bacterial population in an anaerobic digestion with the submerged separation membrane were investigated by using a laboratory-scale reactor at the hydraulic retention time(HRT) 1.0 and 0.5 day. The removal efficiencies of carbohydrate at the HRT 1.0 and 0.5 day were 99.8~99.9% and 98.0~99.6%, respectively. After the 58 days, the mixed liquor volatile suspended solids(MLVSS) concentration at the HRT 1.0 and 0.5 day were approximately 6,050 and 7,750 mg/L, respectively. According to the measurement by the most probable number(MPN) method, the numbers of acidogenic bacteria, $H_2$-utilizing and acetate-utilizing methc.nogenic bacteria were found to be $10^9$, $10^7{\sim}10^8$ and $10^6{\sim}10^8MPN/mL$, respectively. The composition of $CH_4$ in the produced gas was 46~50%. It is suggested that sulfate-reducing bacteria $10^7{\sim}10^8MPN/mL$ play an important role in producing $H_2$ and acetate in sulfate-depleted environment.

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1138-1149
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• 2017

The use of microalgal biomass is an interesting technology for the removal of heavy metals from aqueous solutions owing to its high metal-binding capacity, but the interactions with bacteria as a strategy for the removal of toxic metals have been poorly studied. The goal of the current research was to investigate the potential of Burkholderia tropica co-immobilized with Chlorella sp. in polyurethane discs for the biosorption of Hg(II) from aqueous solutions and to evaluate the influence of different Hg(II) concentrations (0.041, 1.0, and 10 mg/l) and their exposure to different contact times corresponding to intervals of 1, 2, 4, 8, 16, and 32 h. As expected, microalgal bacterial biomass adhered and grew to form a biofilm on the support. The biosorption data followed pseudo-second-order kinetics, and the adsorption equilibrium was well described by either Langmuir or Freundlich adsorption isotherm, reaching equilibrium from 1 h. In both bacterial and microalgal immobilization systems in the co-immobilization of Chlorella sp. and B. tropica to different concentrations of Hg(II), the kinetics of biosorption of Hg(II) was significantly higher before 60 min of contact time. The highest percentage of biosorption of Hg(II) achieved in the co-immobilization system was 95% at pH 6.4, at 3.6 g of biosorbent, $30{\pm}1^{\circ}C$, and a mercury concentration of 1 mg/l before 60 min of contact time. This study showed that co-immobilization with B. tropica has synergistic effects on biosorption of Hg(II) ions and merits consideration in the design of future strategies for the removal of toxic metals.

• The Korean Journal of Mycology
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• v.15 no.2
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• pp.80-86
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• 1987

The author isolated high cellulolytic fungi from natural sources and determined optimal condition of protoplast formation and fusion as fundamental step for improvement of the isolated it's cellulolytic ability. Three different cellulolytic fungi, such as Aspergillus sp., Penicillium sp. and Trichoderma sp., were isolated from soil. Their cellulolytic activities were compared with that of Aspergillus niger which was useful industrially and had cellulase activity. It was Aspergillus sp. that showed the highest activity of all these four fungi. And then it was followed by Penicillium sp., Trichoderma sp., and Aspergillus niger in order. An auxotrophic mutant of Aspergillus sp. was obtained by UV mutagenesis method. Having try to produce protoplast from mycelia, the author found that ${\beta}-glucuronidase$, at pH 6.0, was effective cell-wall lytic enzyme. And the optimal concentration of this enzyme was 5,000 unit/ml. Regeneration rates of wild type, met. auxotroph and arg. auxotroph, in presence of osmotic stabilizer, were 7. 0%, 7. 5% and 5.2%, respectively. PEG with M.W. 6,000 was effective stimulator for protoplast fusion in the concentration of 30% (W IV). In such a condition, we obtained 1.2% cell fusion rate.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.98-98
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• 2003

무순에는 비타민 C가 많이 들어 있어 겨울철 비타민 공급원뿐만 아니라 디아스타제라는 효소가 들어 있어 소화를 촉진시키는 역할을 한다. 그 외에도 거담제 및 건위제 작용을 하고 음주로 인한 토혈해소, 천식에도 좋아 약용하기도 한다. 본 연구에서는 이용가치는 적지만 농가 소득증대에 기여 할 수 있으며 소화를 촉진시키는 무순, 또는 무싹기름이라고 일컬어지는 무순을 추출용매에 따라 생리활성 효과 분석하고 영양학적 가치가 가장 높은 시기의 무순을 선택함으로써 올바른 섭취의 기초자료를 마련하고 그 기능성을 확인하여 기능성 식품소재 및 기능성 화장품 소재로써의 활용을 검토하고자 하고자 한다. 무순을 4일, 8일, 12일에 따라 incubator에 배양하여 시기별로 채취하여 동결건조 한 후 70% Ethanol, 80% Methanol, 75% acetone, 열수로 환류 추출한 후 시료로 사용하였다. 각 용매 추출물에 대해 DPPH free radical 소거능 실험에서는 acetone 추출물에서 89.18%로 가장 높은 전자공여능을 나타냈으며 각각의 추출용매에서 성장 4일과 12일의 무순에서 높은 전자공여능을 보였다. 아질산염 소거능에서는 pH 1.2의 조건에서 가장 높은 아질산염 소거능을 보였고, 열수 추출물에서 89.70%로 가장 높은 소거능을 보였다. pH 4.2조건에서는 열수추출물의 소거능이 가장 좋았고, pH 6.0 조건에서는 가장 낮은 소거능을 보였으며, Ethanol 과 Methanol 추출물에서 23.55∼37.41%의 소거능을 보였다. SOD유사활성은 성장 8일에서 모두 낮은 활성을 보였으며, 성장 4일과 성장 12일의 무순에서는 큰 차이를 보이지 않았지만, Methanol 추출물중 성장 12일에서 27.41%의 SOD유사활성을 보였다.ic acid는 28.8∼51.7 mg%, 미강에서 321.4∼438.4 mg% 범위로 나타났다. 현미, 백미 및 미강에 함유된 총 폴리페놀의 함량을 표준 페놀화합물로 카테친을 사용하고 비색법에 의하여 측정하였을 때 오대 현미의 폴리페놀 함량은 78.4 mg%, 남평 현미 88.8 mg% 였다. 도정한 백미 중의 총 폴리페놀 함량은 30.3∼56.9 mg%, 미강이 541.5∼472.6 mg%의 범위였다. 이상과 같이 쌀에는 phenolic acid 및 총 폴리페놀이 상당량 함유되어 있으며 특히 배유보다는 강층에 많이 존재하므로 이들 성분의 효율적인 이용을 위한 쌀의 섭취방안이 필요한 것으로 나타났다. 유의적인 상관관계를 나타내고 있어 백편의 조직감은 Compression force 와 Work ratio로 대치할 수 있을 것이라고 사료된다. 수분함량은 기계적 검사보다 관능검사와 더욱 높은 상관관계를 나타냈다.내었다. 항균활성이 우수한 생약재를 농도별로 활성을 조사한 결과, 물 추출물과 10% Ethanol 추출물 모두 낮은 농도에서도 우수한 항균활성을 나타내었다.취와 함께 점질성 갈변물질이 생성되었다. 이와 같은 결과로 볼 때, BAAG의 처리는 BAAC의 경우보다 가격은 저렴하면서도 항균력은 우수한 천연 항균복합제재로써 농산물 식품원료에 적용하여 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다. 과일 등의 포장제로서 이용할 가능성을 확인하였다.로 [-wh] 겹의문사는 복수 의미를 지닐 수 없 다. 그러면 단수 의미는 어떻게 생성되는가\ulcorner 본 논문에서는 표면적 형태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elem

• Korean journal of applied entomology
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• v.58 no.4
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• pp.313-317
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• 2019

Stink bugs (Hemiptera: Pentatomidae) are economically important pests of fruit trees in Korea. The aim of the present study was to survey the relative abundance of stink bugs on four stone fruits, maesil (Prunus mume Sieb. et Zucc), cherry (Prunus avium L.), plum (Prunus salicina Lindl), and peach (Prunus persica (L.) Batsch), from 2017 to 2019 in the field. Four stink bug species were observed, including Carbula putoni (Jakovlev), Dolycoris baccarum (L.), Halyomorpha halys (Stål), Plautia stali Scott. H. halys was the most abundant (65%), followed by P. stali (26%), C. putoni (7%), and D. baccarum (2%). H. halys was the dominant species in maesil, cherry, and peach fruits, whereas P. stali was the dominant species in plum fruits. Most (81%) of the stink bugs observed were adults, with nymphs accounting for only 19% of the observed specimens. More stink bugs were observed during the late season than during the early season. These finding suggest that control strategies should be developed for the management of H. halys and P. stali at harvest in stone fruit tree orchards in Korea.

• Korean Journal of Optics and Photonics
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• v.10 no.6
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• pp.500-506
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• 1999

We designed and fabricated a bidirectional optical transceiver module for low cost access network. An integrated chip forming a pin-PD on an 1.3 urn FP-LD was assembled by flip-chip bonding on a Si optical bench, a single mode fiber with an angled end facet was aligned passively with the integrated chip on V-groove of Si-optical bench. Gaussian beam theory was applied to evaluate the coupling coefficients as a function of some parameters such as alignment distance, angle of fiber end facet, vertical alignment error. The theory is also used to search the bottle-neck between transmittance and receiving coupling efficiency in the bi-directional optical system. Tn this paper, we confirmed that reduction of coupling efficiency by the vertical alignment error between laser beam and fiber core axis can be compensated by controlling the fiber facet angle. In the fabrication of sub-module, a'||'&'||' we made such that the fiber facet have a corn shape with an angled facet only core part, the reflection of transmitted laser beam from the fiber facet could be minimized below -35 dE in alignment distance of 2: 30 /J.m. In the same condition, transmitted output power of -12.1 dEm and responsivity of 0.2. AIW were obtained.