• Journal of Animal Science and Technology
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• 제47권4호
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• pp.547-554
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• 2005

본 연구는 메주에서 순수 분리된 메주곰팡이의 대표적 균종인 황국균(Aspergillus oryzae; AO)으로 만든 AO culture와 Salmonella 병원특이 유전자를 삽입한 형질전환 AO(TAO) culture가 산란계의 생산성, 계란 품질 및 장내 미생물 균총에 미치는 영향을 규명하고자 실시하였다. 39주령 산란계 Hy-line Brown 840수를 공시하여 대조구, AO culture 0.2%와 0.5%, TAO culture 0.2%와 0.5%, UV를 조사하여 단백질 분해효소를 감소시킨 mutant에 Salmonella 병원 특이 유전자를 삽입한 형질전환 AO(TMAO) culture 0.2%와 0.5% 첨가구들을 비교하였다. 각 첨가구는 6반복, 반복당 20수씩, 한 케이지 당 2수씩 배치하여 8주간 사양시험을 실시하였다. 사양시험 결과 모든 산란 생산성 및 계란 품질 관련 조사항목에서 처리간에 유의한(P<0.05) 차이가 있었다. TAO culture 0.2% 첨가구가 산란 생산성에 있어서 유의적으로 가장 높았으며, 난중은 모든 AO 첨가구들이 대조구에 비해 유의적으로 낮거나 낮아지는 경향을 나타내었다. 연파란율은 TMAO culture 0.5% 첨가구가 가장 낮았다. 사료섭취량과 사료요구율은 대조구와 모든 AO 첨가구들간에 유의적 차이가 나타나지 않았다. 난각 강도는 대조구 보다 모든 AO 첨가구들에서 유의적으로 높게 나타났으며, 난황 색도는 TMAO culture 0.5% 첨가구에서 가장 높았다. 난각 색도와 Haugh unit은 대조구와 모든 AO 첨가구들간에 유의적 차이가 나타나지 않았다. 장내 미생물 균총(Salmo- nella spp., E. coli. Lactobacilli spp.)에서는 유의적(P<0.05) 차이가 있었다. AO culture 첨가에 의해서 Lactobacilli spp.의 수는 증가되고, E. coli 및 Salmonella spp.의 수는 감소되었다. 특히 TAO와 TMAO culture 첨가구에서는 AO culture 첨가구보다 Salmonella spp. 및 E. coli 억제효과가 컸으며 첨가수준(0.5% vs 0.2%) 간에는 유의한 차이가 없었다. 결론적으로 TAO culture 0.2% 첨가는 산란 생산성 증가에 효과가 있었으며 TAO 및 TMAO culture 0.2% 첨가는 장내 E. coli 및 Salmonella spp.의 감소에 유의한 효과가 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권4호
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• pp.518-523
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• 2014

There are multiple experiments conducted with male Korean native ducks (KND) to evaluate the optimal levels of limiting amino acids (AA). In Exp. 1, a total of 450 one-d-old male KNDs were divided into five groups with six replicates and fed experimental diets with varying levels of lysine, total sulfur amino acids (TSAA) and threonine (T1, 0.90/0.74/0.70%; T2, 1.00/0.82/0.77%; T3, 1.10/0.90/0.85%; T4, 1.20/0.98/0.93%; T5, 1.30/1.07/1.01%) to 21 d of age. In Exp. 2, one-d-old male KND were received and fed commercial starter diet from hatching to 21 d of age, and then divided into five groups with six replicates and fed one of five diets varying levels of lysine, TSAA, and threonine (T1, 0.73/0.62/0.54%; T2, 0.80/0.68/0.60%; T3, 0.87/0.74/0.65%; T4, 0.94/0.80/0.70%; T5, 1.01/0.86/0.75%) during 22 to 56 d of age, respectively. The BW gain was linearly increased as dietary limiting AA levels increased to 1.20% lysine, 0.98% TSAA and 0.93% threonine. There were no significant differences in feed intake, gain:feed and uniformity among groups. In Exp. 2, the BW gain and gain:feed were not affected by dietary limiting AA levels. There were no significant differences in carcass characteristics and meat quality among groups. The growth performance and carcass characteristics did not show the significant response to increasing dietary limiting AA levels in KND during 22 to 56 d of age. In conclusion, the levels of lysine, TSAA and threonine necessary to maximize growth for starter phase were at least 1.20%, 0.98%, and 0.93%, respectively. On the other hands, KND require relatively low levels of limiting AA for late growth and carcass yield. The dietary levels of 0.73% lysine, 0.62% TSAA and 0.54% threonine appear to be adequate during growing phase.

• Nuclear Engineering and Technology
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• 제49권7호
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• pp.1547-1554
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• 2017

VESTA (Verification of Ex-vessel corium STAbilization) and VESTA-S (-small) test facilities were constructed at the Korea Atomic Energy Research Institute in 2010 to perform various corium melt experiments. Since then, several tests have been performed for the verification of an ex-vessel core catcher design for the EU-APR1400. Ablation tests of an impinging $ZrO_2$ melt jet on a sacrificial material were performed to investigate the ablation characteristics. $ZrO_2$ melt in an amount of 65-70 kg was discharged onto a sacrificial material through a well-designed nozzle, after which the ablation depths were measured. Interaction tests between the metallic melt and sacrificial material were performed to investigate the interaction kinetics of the sacrificial material. Two types of melt were used: one is a metallic corium melt with Fe 46%, U 31%, Zr 16%, and Cr 7% (maximum possible content of U and Zr for C-40), and the other is a stainless steel (SUS304) melt. Metallic melt in an amount of 1.5-2.0 kg was delivered onto the sacrificial material, and the ablation depths were measured. Penetration tube failure tests were performed for an APR1400 equipped with 61 in-core instrumentation penetration nozzles and extended tubes at the reactor lower vessel. $ZrO_2$ melt was generated in a melting crucible and delivered down into an interaction crucible where the test specimen is installed. To evaluate the tube ejection mechanism, temperature distributions of the reactor bottom head and in-core instrumentation penetration were measured by a series of thermocouples embedded along the specimen. In addition, lower vessel failure tests for the Fukushima Daiichi nuclear power plant are being performed. As a first step, the configuration of the molten core in the plant was investigated by a melting and solidification experiment. Approximately 5 kg of a mixture, whose composition in terms of weight is $UO_2$ 60%, Zr 10%, $ZrO_2$ 15%, SUS304 14%, and $B_4C$ 1%, was melted in a cold crucible using an induction heating technique.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.137-137
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• 2009

Thin-film transistors (TFTs) that can be prepared at low temperatures have attracted much attention due to the great potential for flexible electronics. One of the mainstreams in this field is the use of organic semiconductors such as pentacene. But device performance of the organic TFTs is still limited by low field effect mobility or rapidly degraded after exposing to air in many cases. Another approach is amorphous oxide semiconductors. Amorphous oxide semiconductors (AOSs) have exactly attracted considerable attention because AOSs were fabricated at room temperature and used lots of application such as flexible display, electronic paper, large solar cells. Among the various AOSs, a-IGZO was considerable material because it has high mobility and uniform surface and good transparent. The high mobility is attributed to the result of the overlap of spherical s-orbital of the heavy pest-transition metal cations. This study is demonstrated the effect of thickness channel layer from 30nm to 200nm. when the thickness was increased, turn on voltage and subthreshold swing were decreased. a-IGZO TFTs have used a shadow mask to deposit channel and source/drain(S/D). a-IGZO were deposited on SiO2 wafer by rf magnetron sputtering. using power is 150W, working pressure is 3m Torr, and an O2/Ar(2/28 SCCM) atmosphere at room temperature. The electrodes were formed with Electron-beam evaporated Ti(30nm) and Au(70nm) structure. Finally, Al(150nm) as a gate metal was evaporated. TFT devices were heat treated in a furnace at $250^{\circ}C$ in nitrogen atmosphere for an hour. The electrical properties of the TFTs were measured using a probe-station to measure I-V characteristic. TFT whose thickness was 150nm exhibits a good subthreshold swing(S) of 0.72 V/decade and high on-off ratio of 1E+08. Field effect mobility, saturation effect mobility, and threshold voltage were evaluated 7.2, 5.8, 8V respectively.

• 전기화학회지
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• 제3권1호
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• pp.44-48
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• 2000

상온에서 DC-magnetron sputtering으로 증착한 비정질의 $V_2O_5$ 박막을 양극물질로 하여 $V_2O_5/LIPON/Li$으로 구성된 박막형 리튬이차전지를 제작하였다. $V_2O_5$의 양극특성은 액체전해질을 이용한 half cell 구조에서 평가하였으며, $Ar/O_2$ 분압비의 변화에 따라 제작된 $V_2O_5$ 양극은 분압비 80/20에서 가장 좋은 특성을 보였다. 자체 제작한 $Li_3PO_4$ 타겟을 사용하여 RF-sputtering으로 순수한 질소 분위기 하에서 양극 위에 고체전해질 LIPON 박막을 형성하였으며, 1.2-4.0V vs. Li 구간에서 리튬에 대해 반응성이 없는 안정한 화합물임을 확인하였다. 음극으로 쓰인 약 $2{\mu}m$두께의 금속리튬박막은 진공 열 증착법으로 제조하였으며, $V_2O_5/LIPON/Li$의 박막형 리튬이차전지는 $1.2\~3.5V$ 구간에서 초기에 약 $150{\mu}A/cm^2{\mu}m$의 높은 방전용량을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권9호
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• pp.1462-1467
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• 2007

This study investigated the effect of chemical treatments on tannins (condensed and hydrolysable) and on the trypsin inhibitor (TI) activity in salseed meal. Triplicate samples of ground salseed meal (1 kg) were mixed with 820 ml of either distilled water (pH 5.3), 0.67 M acetic acid (pH 2.4), 0.67 M sodium bicarbonate (pH 8.2) or 2% polyvinyl-pyrrolidone (PVP) solution. The material was placed in airtight plastic containers and incubated at $37^{\circ}C$ for 0, 3, 6, 12, 24, 48 and 72 h. Samples of untreated salseed meal which had not been subjected to soaking or incubation were run through the analysis to serve as control. Addition of water, acetic acid, sodium bicarbonate and PVP solutions to salseed meal and subsequent anaerobic incubation at $37^{\circ}C$ significantly reduced chemically detectable tannins. At each incubation time, alkali solution was more effective than its counterparts. The effect of acidic solution on hydrolysable tannin was least among the treatments. All the treatments reduced TI activity of salseed meal. The reduction in TI activity by these treatments was similar and ranged between 80-84%. Treatment time effected a decrease in the contents of antinutritional substances. However, the effect of the treatment with the reagents, even for zero incubation time, was quite pronounced. It may be concluded from the present results that the treatment of salseed meal with sodium bicarbonate (0.67 M) is more effective in reducing hydrolysable and condensed tannin contents than PVP, water and acid solutions. Treatment with sodium bicarbonate solution is more economical and easier to handle than acid and PVP treatments. Incubation of the treated material for 12 h is reasonably effective, economical and safe from any mould growth.

• 한국축산시설환경학회지
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• 제12권1호
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• pp.7-12
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• 2006

본 연구에서는 육성 비육돈 슬러리를 이용하여 슬러리의 환경조건에 따라 슬러리로 부터의 암모니아 발생 특성을 분석코자 하였다. 슬러리의 온도와 pH를 조절하여 슬러리로부터 발생하는 암모니아 농도를 측정 분석한 결과 슬러리의 온도가 높을수록 슬러리로 부터 발생하는 암모니아 농도는 급격히 증가하는 것으로 나타났고, 슬러리의 pH를 5, 6, 7, 8의 4수준으로 조절하여 각각의 온도에 따라 발생하는 암모니아 농도를 측정한 결과 pH 5, 6에서는 암모니아 가스가 검출되지 않았으나 pH 7, 8에서는 많은 양의 암모니아 가스가 검출되었고 양돈 슬러리의 pH가 높을수록 발생하는 암모니아 가스가 많이 발생하는 것으로 분석되었다. 본 연구결과 슬러리의 온도를 낮추어 주거나 슬러리의 pH를 낮춤으로써 슬러리로부터 발생하는 악취가스를 크게 줄일 수 있을 것으로 판단되었다.

• 한국잡초학회지
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• 제17권3호
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• pp.262-268
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• 1997

경북지역 벼재배지에서 잡초분포현황을 조사하여 잡초방제의 기초자료로 활용코자 조사한 결과는 다음과 같다. 1. 생활사별 잡초 분포에 있어서 일년생이 56.5%로서 다년생 43.5% 보다 많았으며 형태적 분포는 화본과 25.2%, 사초과 12.3%, 광엽잡초 62.5%로 분포하였으며 화본과 잡초의 발생이 1971년, 1981년보다 증가하는 경향이었다. 2. 지대별 잡초 분포에서 평야지, 중간지, 냉조풍지에서는 피, 벗풀, 올방개, 물달개비가 우점초종이었으며 답종류별로는 보통답과 습답은 우점초종이 서로 비슷하게 발생하였으나 사질답에서는 잡초 발생 양상이 다르게 나타났다. 3. 손이앙답과 건답직파에서는 피의 우점이 가장 높았으나 기계이앙묘에서는 벗풀, 여뀌바늘 등이 우점잡초였고 이앙기별로는 이앙기가 늦어질수록 피의 발생이 많았다. 4. 경북지역의 주요 우점잡초는 피, 벗풀, 여뀌바늘, 올방개, 물달개비 순으로 나타났다.

• Journal of Biosystems Engineering
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• 제13권3호
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• pp.32-43
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• 1988

This study was attempted to investigate the pneumatic separation on separating unit of a combine harvester. The aerodynamic characteristics of threshed materials were analyzed by experiments. The air velocity distribution within the separation chamber was measured for various speeds of the winnower and suction fans to find out the operational and design conditions of the separating unit which would serve for reducing the grain loss from chaff outlet. The results of study arc summarized as follows: 1. Based on the separation curve of threshed materials analyzed, it was shown that three different kind. of materials-kernels, straw chaff, and leaf chaff were as a whole able to be separated pneumatically, regardless of varieties. However, a small amount of the separation grain loss may be expected to occur if the complete separation between kernels and straw chaff would be undertaken because some portion of their separation curve were overlapping. 2. The analysis of air velocity distribution showed that the separation chamber may be divided into two regions, the discharging and separating. The air velocity of the discharging region was 5-15 m/s and that of the separating region 2-5 m/s. 3. The air movement of the separation chamber may be a turbulence flow, being its speed became greater as it moves from the left to the right section of the separation chamber. The equi-speed line. of air flow had a steep gradient in between the discharging and the separation regions. The air velocity in the discharging region was much higher than the terminal velocity of kernels, because of which those kernels appearing in the region could be possibly exhausted as the grain loss from the chaff outlet. 4. The motion trajectory of threshed material in the separating region was dominantly affected by the winnower fan, on the other hand, its motion in the discharging region was affected by suction fan. 5. The grain loss from the chaff outlet was affected greatly by the winnower fan and the trace of kernel movement. It was observed that the optimum working speed to give minimum grain loss from chaff outlet for the combine tested should be maintained at 950~1,150 rpm for the winnower fan and 1,850 rpm for the suction fan. 6. It was shown that a large portion of grain loss from chaff outlet may occur when the kernels may bump against a portion of separation chamber wall and those kernels thus scattered into the discharging region were sucked by the suction fan. It was accordingly recommended that a new design of the wall of separation chamber so as to bump down kernels may be necessary to reduce grain loss from the chaff outlet.

• 농약과학회지
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• 제6권1호
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• pp.36-41
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• 2002

Sulfonylurea계 제초제 pyrazosulfuron-ethyl과 bensulfuron-methyl을 대상으로 다년생 잡초의 재생특성과 저장전분의 변화 양상을 조사하였다. Pyrazosulfuron-ethyl을 처리하였을 때 너도방동사니가 24일 후 재생되어 5가지 다년생 잡초 중 가장 빠르게 재생하였으며, 올방개, 올미, 벗풀 등이 각각 $30{\sim}39$일 이후부터 재생하였고, 가래는 55일 이후 재생되었다. 너도방동사니의 마디의 수와 엽기별 처리에 따른 재생력의 차이에서는 bensulfuron-methyl에 대하여 4마디 식물체가 2마디 식물체보다 약 2배의 재생력을 보였고, 처리시기가 2엽기, 3엽기, 4엽기로 늦어질수록 재생력이 증가하였다. 크기에 따른 올방개의 재생력은 $0.3{\sim}0.5g$ 크기의 올방개보다 $1{\sim}1.5g$ 크기의 올방개가 bensulfuron-methyl에 대하여 재생력이 강한 것으로 나타났다. 처리시기에 따른 올방개의 재생력은 2엽기 처리보다 3엽기 처리에서 재생율이 감소되었다. 모경에 대한 의존기간은 벗풀의 경우 맹아된 후 12일이며, 올방개는 18일로 나타났다. 정상적으로 생장할 경우 영양번식체 내의 전분이 고갈되는 시기는 벗풀의 경우 맹아 후 18일, 올방개의 경우 27일로 나타났으며, 유리당의 최고치는 벗풀의 경우 맹아 후 9일, 올방개의 경우 18일로 나타났다. 올방개 괴경은 벗풀 괴경보다 1.5배 많은 전분을 함유하고있었다.