• KSBB Journal
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• v.18 no.5
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• pp.347-351
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• 2003

The extraction of glycyrrhizic acid from licorice using supercritical carbon dioxide (SCCO$_2$) was investigated with respect to the effects of extraction parameters such as the kind and amount of modifier, temperature, pressure, and extraction time. The conventional organic solvent extraction was also conducted for a quantitative comparison. The content of glycyrrhizic acid in crude extracts was analyzed by HPLC and the yield of glycyrrhizic acid was computed as a weight percent recovery. The optimal pressure and temperature for SCCO$_2$ extraction were found to be 40 MPa and 80$^{\circ}C$, respectively, when SCCO$_2$ was modified with 70% aqueous ethanol. Under the same pressure and temperature, the highest recovery was attained to be 104.57% in the first 60 min when the concentration of 60%, aqueous ethanol in SCCO$_2$ was 15%.

• Reproductive and Developmental Biology
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• v.30 no.1
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• pp.7-11
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• 2006

This study was conducted to examine the effects of hormone and sodium pyruvate on in vitro maturation of canine oocytes. Canine oocytes were collected from the ovaries of dogs and cultured in NCSU-37 medium with hormones and sodium pyruvate for 72 hr. Oocytes matured to the metaphase II (MII) stage were observed only from estradiol $17{\beta}\;(E_2)$, and the presence of gonadotropin did not improve the nuclear maturation. No oocytes were developed to the MII stage when $E_2$ was added to medium during the first 6 and 24 hrs of culture period. The presence of $E_2$ during the whole culture period enhanced the nuclear maturation to the MII stage (6.0%, P<0.05). High concentration of sodium pyruvate (2.5 mM) slightly enhanced the nuclear maturation to the metapahse I (HMI) stage, but not the MII stage. the result of the present study shows that the presence of $ E_2$ during the whole culture period of 72 hr enhances the maturation of canine oocytes to the M stage, but sodium pyruvate does not affect the nuclear maturation of the canine oocytes.

• KOREAN POULTRY JOURNAL
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• v.4 no.6 s.32
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• pp.85-87
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• 1972

결과적으로 시판 피마자박을 성장하는 병아리 혹은 기타 단위 동물의 단백질 사료로서 이용하기위해서는 다시 제독처리해야함을 알 수 있다. 제독처리 방법 중에서도 끓는 물로 여과하여 독소를 축출하는 방법이 가장 좋고 이 방법이 독소를 전부는 아닐지라도 대부분 제거시키는 방법이다. 피마자박의 아미노산조성을 볼때 그 생물가가 낮은 주요 원인이 라이신 트립토판 그리고 S 함유 아미노산이 부족하기 때문임을 알 수 있다. 제독처리한 피마자박의 라이신과 메치오닌 그리고 트립토판을 첨가하면 대두단백+메치오닌(0.2$\%$) 만큼 병아리성장에 유효함을 알 수 있다. 다른 필수 아미노산의 첨가는 별 효과가 없고 어분 대두단백 혹은 난백의 첨가도 부족한 아미노산을 첨가해 주는 것만큼 효과적이 아니었다. 라이신이 가장 먼저 부족되는 것이고 다음 트립토판이다. 메치오닌은 NRC 권장량의 60$\%$ 밖에 안되나 실제로 피마자박에 적절히 함유한다. 이것은 NRC 권장량이 너무 높다는 스콧트와 그의 동료의 주장과 일치하고 있다. 체중변화를 볼 때 흥미있는 것은 피마자박에 어분을 첨가하면 각 그룹간 병아리 체중의 차이가 심한데 어분대신 아미노산을 첨가하면 그 차이가 현저히 감소한다. (25$\%$와 15$\%$) 이러한 현상은 아미노산이 부족한 사료를 먹으면 성장에 필요한 아미노산 요구량이 개체별로 차이가 있기 때문일 것이다. 피마자박에 아미노산을 첨가하면 단백질 최종이용율이 현저히 증가하나, 이정도는 대두단백+메치오닌(0.2$\%$)에 비하면 이용율이 낮은데 그 이유는 아마 피마자박중의 리그닌과 조섬유 함량이 높기 때문일 것이다. 피마자박의 사료는(사료중 40$\%$) 조섬유가 약 15$\%$나 되어 이것 때문에 사료 섭취량이 대두단백사료 보다 증가하게 되고 사료섭취량이 많으면 단백질 섭취도 많게 되어 피마자박의 단백질 이용율이 낮게 된다. 즉 최종 단백질 이용율은 단백질 섭취량과 역비례한다. 만약 피마자박의 조섬유를 일부 혹은 전부 제거하기만 한다면 양계및 기타 단위 동물의 단백질 사료 자원으로서 그 가치가 훨씬 높아질 것이다. 더욱 희망적인 것은 피마자박 생산자측에 의하면 피마자씨 껍질의 상당한 부분을 제거하는 것은 가능하다고 한다.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.385-390
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• 2015

In order to develop an eco-friendly biofertilizer, a plant growth promoting rhizobacterium (PGPR), Bacillus sp., SH1RP8 was investigated. SH1RP8 was lyophilized via freeze-drying along with other protective agents that protect cells from lysis. The freezedried powder of Bacillus sp. SH1RP8, containing 5% skim milk (w/v), exhibited the highest survival rate of 30.6% among all the protective agents (skim milk, glucose, and peptone). The lyoprotective effect of the skim milk, mixture including 5% skim milk, and substrates on the survival of the test strain was examined. Control group was added only skim milk and test groups were added skim milk and other substrates. As a result, the group supplemented with both glycerol and 5% skim milk showed the protective effect much higher by 214.29% than the control group. Freeze-dried Bacillus sp. SH1RP8 could be a good candidate as a potential biofertilizer due to its effective PGPR activity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.49-58
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• 2010

This experiment was carried out to estimate the nutritive value of mixed-sowing winter forage crop and whole crop barley by investigating the effects of feeding mixed-sowing winter forage crop and whole crop barley in KBG (Korean black goat) on feed intake, average daily body weight gain, nutrient digestibility and nitrogen retention. The 12 male KBG were divided into four experimental groups - i.e. T1: barley silage added group, T2: mixed-sowing hairy vetch silage added group, T3: mixed-sowing field peas added silage, T4: mixed-sowing Italian rye grass added silage group. Three KBG per each treatment were allotted into individual metabolic cages by Latin-square design. The results from this study are as follow. The DMI (dry matter intake) and organic matter intake in T4 were significantly (p<0.05) higher than those in T1 and T3 and crude protein intake in T4 also recorded the highest among treatments (p<0.05). The highest values in intakes of ADF and NDF were observed in T4 followed by T2, T1 and T3 in order. The average daily body weight gains in T4 and T2 were significantly (p<0.05) higher than those in TI and T3. The dry and organic matter digestibility in T2 and T4 were significantly (p<0.05) higher than those in T1 and T3. The crude protein digestibility in T1 was significantly (p<0.05) lower than those in T2 and T4. The nitrogen intakes in T2 and T4 were significantly (p<0.05) higher than those in T3. The results obtained from this study suggested that the feeds supplemented with whole crop barley with hairy vetch and Italian rye grass mixture silage increased KBG productivity resulted from increases in feed intake, nutrient digestibility and nitrogen retention.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.105.2-105.2
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• 2010

전처리 후 얻어진 셀룰로스 고분자를 단당류로 전환하기 위해서는 셀룰라제를 이용한 당화 과정이 필요하다. 통상 실험식 연구에서는 셀룰로스 당화시 당수율을 최대로 하기위해 pH조절을 위한 Citrate buffer와 미생물 오염을 막기 위한 Autoclave에서의 멸균 과정을 거친다. 하지만 대량생산을 목적으로 하는 산업체에서는 적용이 어렵다는 문제점이 있다. 따라서 본 연구에서 이를 대신하여 산업체에서 적용 가능한 당화전환 공정의 효율성을 평가하고자 하였다. Autoclave 멸균을 대체하는 공정으로 항생제 첨가와 여과에 의한 제균을 선택하였고, citrate buffer를 대신하여 buffer를 첨가하지 않은 물을 pH를 조정하여 사용 하였다.실험결과 기존의 당화공정을 사용하였을 때 당화율이 81%이었고, pH를 조절한 제균 water에 항생제를 첨가하는 공정은 71%로 나머지 배지들 중 가장 높은 당화율을 나타냈다. 이것은 기존의 당화율보다 10% 낮은 수치이나 공정비를 교려하여 봤을 때 효율성 있는 공정으로 판단된다.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.729-734
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• 1995

원자력용 316L강에 질소를 첨가한 경우의 고온 인장성질을 조사하였다. 온도가 증가하면 인장강도는 감소하다가 온도범위가 30$0^{\circ}C$~50$0^{\circ}C$에서는 일정한 값을 나타낸 후 급격한 감소를 나타내었고 연신율은 감소하다가 40$0^{\circ}C$에서 최소값을 나타낸 후 다시 증가하는 경향을 나타내었다. 질소를 첨가하면 인장강도증가와 함께 연신율도 증가하였다. 동적변형시효 온도구간에서 변형속도변화에 따른 인장강도 및 연신율의 변화는 매우 작다. 동적변형시효를 위한 활성화에너지를 구해본 결과 동적변형시효를 일으키는 원소는 Cr이다. 질소를 첨가하면 동적변형시효가 발생되는 온도가 고온 쪽으로 이동되었는데 이것은 질소가 Cr과의 상호작용에 의해 Cr의 확산속도를 낮추기 때문이다. 가공경화지수는 동적변형시효와 회복의 영향으로 40$0^{\circ}C$에서 최대값을 나타내었으며 이 온도는 연신율이 최소값을 나타내는 온도와 인장강도가 일정하게되는 온도와 일치하므로 강도강화기구는 동적변형시효로 판명되었다.

• Korean Journal of Animal Reproduction
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• v.20 no.1
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• pp.1-8
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• 1996

The objective of this study was to determine effects of oviductal fluid on the sperm penetration and subsequent in vitro development of porcine oocytes. The addition of oviductal fluid to the fertilization medium decreased sperm pen etration and the mean number of spermatozoa in penetrated eggs. The number of spermatozoa firmly bound to zona pellucida was also decreased in the presence of oviductal fluid. Chlortetracy cline (CTC) fluorescence patterns were used to determine incidence of capacitation and acrosome reaction. The proportion of capacitated a and acrosome free spermatozoa increased when spermatozoa were exposed for 1.5 and 3 h to oviductal fluid. These results suggest that the factor(s) in secretion from the oviduct reduces polyspermic fertilization and the number of spermatozoa that will penetrate porcine oocytes. The reduction of polyspermic penetration by oviductal secretions may be due to a reduced number of spermatozoa in the fertilization me-dium into an intact acrosome.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.5
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• pp.87-92
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• 2010

This study set up 25, 35% for silica fume, SFFB's 2 level and water-combination material ratio, silica fume 10% for substitution ratio, and 4 level of SFFB 5, 10, 15(%) in order to compare and analyze the quality characteristic of ultra high strength concrete according to the substitution ratio of silica fume free binder (SFFB) that can be utilized as a substitute material for silica fume. As a result of an experimentation, the lower water-combination material ratio was, the higher addition ratio of high performance water-reducing agent for securing target liquidity increased, and it indicated the tendency that addition ratio of high performance water-reducing agent decreases because of material characteristic that SFFB has a lower absorptiveness than silica fume. The best strength was shown when SFFB substitution ratio is 10% at compressive strength and when substitution ratio is 15% at tensile strength, and it was indicated that at autogenous shrinkage contraction decreases compared to Plain(SF) regardless of substitution ratio of W/B and SFFB.

• Journal of the Korean Ceramic Society
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• v.34 no.3
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• pp.281-288
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• 1997

The effects of 0 to 6 mol% excess 91PbO-9WO3 addition on the microstructure and the dielectric pro-perties in 40Pb(Mg1/3Nb2/3)O3-30PbTiO3-30Pb(Mg1/2W1/2)O3 ternary system were investigated. Excess 91PbO-9WO3 addition enhanced densification at relatively lower temperature due to the formation of liquid phase. The dielectric constant of the specimen with standard composition was 16,400 and that of specimen with 1 mol% excess additive was the maximum of 18,500. And more than 2 mol% excess addition decreased dielec-tric constant. Specimens with 2~4 mol% 91PbO-9WO3 addition showed dual peak maxima in the tem-perature dependence of dielectric constant. In the specimens which have more than 5 mol% excess addition a new phase with W-rich composition was formed at grain boundary.