• 대한수의학회지
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• 제27권2호
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• pp.331-334
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• 1987

The effects of ethylene glycol as a cryoprotective agent on the survival of frozen-thawed mouse embryos were examined. The effects of the stage of development of ethylene glycol were also examined. Eight-cell embryos, morulae, early blastocysts and mid-blastocysts were recovered from superovulated immature ddY mice. Ethylene glycol was added to the embryos in 5 equal increments 5 minutes apart, giving a final concentration of 1.5M. The embryos were cooled to ${-6^{\circ}C}$ at ${1^{\circ}C/min}$ and seeding was induced at ${-6^{\circ}C}$. After being held for a further 5minutes at the seeding temperature, the samples were cooled to ${-35^{\circ}C}$ at ${0.3^{\circ}C/min}$ and then transferred to liquid nitrogen. Rapid thawing was done by placing the straws in ${37^{\circ}C}$ water. The thawed embryos were diluted in PBS of same time and manners as adding procedures. Survival of 8-cell embryos and morulae were assessed as a normal development of the embryos to the blastocyst stage and expanding blastocyst after 54 hours and 48 hours of in vitro culture, respectively. While those of the early and mid-blastocysts were assessed to the expanding blastocyst stage after 24 hours of in vitro culture. The survival rates of 8-cell embryos, morulae, early blastocysts and mid-blastocysts were 73.8%, 74.3%, 87.8% and 77.4%, respectively. Significant difference on the survival rate among the four stages of development was not observed.

• 한국세라믹학회지
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• 제52권4호
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• pp.273-278
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• 2015

${\alpha}-Al_2O_3$ was synthesized by solvothermal synthesis using ${\alpha}-Al_2O_3$ seed, precursor of fine boehmite (Al(OOH)) or gibbsite ($Al(OH)_3$), and 1, 4-butanediol solvent. The seed content and precursor type were selected as variables in order to synthesize ${\alpha}-Al_2O_3$. The formation time of ${\alpha}-Al_2O_3$ was reduced and the size of the particles was decreased with addition of the seed. When the seed content was increased, the size of the synthesized ${\alpha}-Al_2O_3$ was reduced. Morphologies of the as-synthesized ${\alpha}-Al_2O_3$ with ${\alpha}-Al_2O_3$ seed were polyhedron-shaped, while the shape was plate-like or polyhedral without the seed, depending on the additives or the average particle size of the boehmite precursor. The aggregation of as-synthesized ${\alpha}-Al_2O_3$ from boehmite was smaller than that from gibbsite. As-synthesized ${\alpha}-Al_2O_3$, with 140 nm size, was obtained by using the seed and boehmite precursor.

• 한국작물학회지
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• 제37권1호
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• pp.86-92
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• 1992

최근들어 우리나라 국민의 식품소비 형태가 점차 고급화됨에 따라 메밀의 어린 식물체와 종실은 건강 별미식품의 원료로서 수요량은 단속 증가될 전망이다. 엽채소용으로 이용되는 메밀의 어린 식물체는 30% 이상의 단백질과 500mg / 100g 이상의 Rutin과 상당한 양의 미네랄, 비타민 함유하여 단경기 재배시 녹채소의 수량은 파종량, 파종기, 재배환경 조건에 따라서 262～2,270 / 10a로 차이가 매우 컸으며 예상조수익도 52.4～183.5만원 / 10a이었다. 엽채소용 메밀의 육묘기간을 20, 25, 30일로 하였을 경우 육묘기간이 길수록 초장, 줄기의 굵기, 잎의 수와 크기가 증대되었다. 4배체품종 신주대메밀의 생체중은 2배체품종 수원재래와 신농001에 비하여 35%가 더 무거웠으며 엽육이 두껍고 잎이 커서 상품가치가 더 좋았다.

• The Korean Journal of Ecology
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• 제15권2호
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• pp.103-115
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• 1992

This dissertation, which has been prepared in the region of cheju(33o31'N, 126o32'E) from may,1987 to appril, 1989, is to elucidate the dominant characteristics of early stages in secondary succession, by examining the life history of erigeron annuus for the seeding depth of a seed was dependent upon the degree of shading. That is, on the area of ocm,the more tense the shading was, the more germination percentage was increased, while, in the case of 1.5cm, it was somewhat increased, when shading bwcame ess and less tense. The rosette of e. annuus, through its relative light intensity was decreased by shading, up to 5% of natural light, showed some strong shade tolerance, which had no difficulty in matter production. The species diversity of mixed-species community was the highest in the middle of April, the lowest in the last of may. The dominance index was the highest in the late may, the lowest in the middle of April. Toward the end of may, the occupation rate of dominance species was the highest. There was a neutral relationship between intraspecific and interspecific, owing to the differentiation of its niche, temporally and spatially. Productive structure of the community revealed a narrow leaf type which was concentratively distributed in the mid part of community height. The relative light intensity of community ground surface was 6.1%, the leaf inclination 60o,the extinction coefficient(k) 0.4, biomass of community 1,045.6 g.d.w./m2,T/Rratio 9.3, C/Frate 7.0 and sumgermanition, shade toarance and community characteristics on erigeron annuus l.in chejumed leaf area index 3.88. through the various life cycles o e.annuus, we can say that it decreases mortality of seeding caused by some stress and disturbance, for germination lasts for a long time at any opportunity available, and it promotes population growth. The strong shade tolerance of a rosette and the variableness of a life from differentiate the niche between intraspecific and interspecific within the community, and avoid the direct competition between them, thus poromoting community growth.

• 한국작물학회지
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• 제44권3호
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• pp.248-252
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• 1999

This study examined the effects of growth retardants and midsummer drainage on lodging-related characters in direct seeding rice culture on flooded paddy surfaces. Treatments included in this study were continuous flooding, two time midsummer drainages (TTD), and inabenfide or trinexapac-ethyl application after TTD. Culm length was reduced most by 11.4cm in trinexapac-ethyl treatment after TTD, followed by 4.1cm in inabenfide treatment after TTD compared to TTD treatment. A significant reduction in culm length occurred at the 3rd internode in inabenfide treatment applied at 40 days before heading (DBH), while trinexapac-ethyl application at 8 DBH reduced the 3rd>2nd>1st internode. The culm diameter of the 4th internode was increased by the application of trinexapac-ethyl following TTD compared to TTD treatment. Thickness of culm wall was significantly increased by trinexapac-ethyl but not by inabenfide applications. Lodging index was the highest in continuous flooding and the lowest in trinexapac-ethyl treatment after TTD. Subsequently, field lodging did not occur in plots treated by trinexapac-ethyl. Rice plants subjected to midsummer drainage or growth retardants showed higher ripened grain ratio and 1000-grain weight, resulting in higher rice yield. These results indicate that trinexapac-ethyl, which can be applied at the relatively later growth stage after proper judgement of lodging occurrence, could be a useful tool for reducing lodging in direct seeding rice culture on flooded paddy fields.

• Current Research on Agriculture and Life Sciences
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• 제23권
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• pp.1-8
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• 2005

경상북도 의성지역의 벼 자동화 육묘시설에서 파종기별 적정 묘대기간을 선정하기 위하여 실험한 결과를 요약하면 다음과 같다. 파종기가 늦어지고 육묘일수가 길어질수록 묘초장은 증가하였다. 의성지역에서 이앙 가능한 묘초장 10cm 이상을 확보하기 위해서는 10일묘는 5월20일, 15일묘는 5월5일이 파종적기로 나타났다. 묘충실도는 파종기가 늦어지고 육묘일수가 길어질수록 불량해졌는데, 10일묘의 경우는 6월 20일 이후, 15일 묘는 5월 10일 이후 파종에서 각각 묘충실도가 크게 나빠지는 경향이었다. 주당수수는 육묘기간이 길어질수록 감소하였고, 수당립수, 등숙률 및 천립중은 일정한 경향이 없는 것으로 나타났다. 1모작인 5월 하순 이앙구의 정조수량은 10일묘에서 748 kg/10a로 가장 높았고 묘대일수가 길어질수록 감소하였으며, 2모작인 6월 27일 이앙구에서도 10일묘를 이앙했을 때 수량성이 가장 높았다.

• 한국결정성장학회지
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• 제17권3호
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• pp.95-101
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• 2007

수열합성 장치를 이용하여 종자 결정이 도포된 알루미나 지지체 위에 제올라이트 박막을 합성하였다. X-선 회절 분석과 전자현미경 사진을 이용하여 반응기 내에 생성된 제올라이트 A 분말과 제올라이트 A박막의 생성과 전이 생성물에 대해 합성온도, 합성시간, 종자결정의 영향에 대해서 고찰하였다. 제올라이트 A박막의 생성은 지지체 표면에 도포된 종자 결정에서 치밀한 연속적인 박막이 형성된 다음 용해과정을 거쳐 결정의 크기가 큰 다결정 층을 형성하고, 최종적으로 소다라이트를 거쳐 무정형으로 진행하였다. 반면에 분말에서는 반응초기부터 소다라이트가 관찰되는데 고정된 제올라이트 A 박막과 다르게 결정주위의 공간적인 차이에 의해 소다라이트가 생성하기에 용이한 공간을 갖기 때문에 소다라이트가 쉽게 생성되는 것으로 생각된다. 합성온도가 높으면 짧은 시간 내에 전이 생성물을 거쳐 무정형으로 진행하였고 온도가 낮으면 합성 시간이 길고 피복도가 다소 낮은 제올라이트 A 박막을 얻었다. $120^{\circ}C$, 12시간에서 피복도가 높은 치밀한 제올라이트 A박막을 합성하였다.

• 한국물환경학회지
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• 제21권1호
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• pp.59-65
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• 2005

A phosphate recovery system from artificial wastewater was developed using a completely mixed phosphorus crystallization reactor, in which powdered converter slag was used as a seeding crystal. In preliminary test, the optimal pH range for meta-stable hydroxyapatite crystallization for high phosphorus concentration was observed to be 6.0 to 7.0, which was different from the conventionally known pH range (8.0~9.5) for effective crystallization in relatively low phosphorus concentration less than 5 mg/L. The average phosphorus removal efficiency in a lab-scaled completely mixed crystallization system for artificial wastewater with about 100 mg/L of average $PO_4-P$ concentration was shown to be 60.9% for 40 days of lapsed time. XRD analysis exhibited that crystalline of hydroxyapatite formed on the surface of seed crystal, which was also observed in SEM analysis. In EDS mapping analysis, composition mole ratio (=Ca/P) of the crystalline was found to be 1.78, indicating the crystalline on the surface of seed crystal is likely to be hydroxyapatite. Particle size distribution analysis showed that average size of seed crystal increased from $28{\mu}m$ up to $50{\mu}m$, suggesting that phosphorus recycling from wastewater with high phosphorus concentration can be successfully obtained by using the phosphorus crystallization recovery system.

• 한국산림과학회지
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• 제87권4호
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• pp.503-509
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• 1998

최근 환경수로서 가치가 높아지고 있는 때죽나무에 대하여 몇 가지 전처리에 의한 종자 발아촉진과 실생묘의 생장상태, 그리고 시기별, 처리별 종자내 성분의 변화 과정을 조사하여 다음과 같은 결과를 얻었다. 1. 1년 이상 노천매장을 해야만 발아가 되는 때죽나무 종자에 몇 가지 전처리를 하여 파종한 결과, $H_2SO_4$ 70% 용액에 30분간 침지 후 $GA_3$ 3,000ppm 처리하여 5개월간 층적처리한 시험구에서 55%의 발아율을 보여 당년 발아가 가능하였다. 2. 파종 후 160일 후에 발아된 치묘의 생장량을 조사한 결과 전처리에 의해 당년 발아된 묘목과 2년 발아된 묘목사이에 차이가 없었다. 3. 때죽나무의 1년 종자에 몇 가지 전처리를 한 후 종자내 성분을 분석한 결과 점차 함수량은 증가하고, 조지방과 탄수화물 및 조회분 등은 감소하여 파종 직전에는 2년 종자의 성분 비율과 유사해졌다.

• 한국작물학회지
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• 제42권6호
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• pp.673-677
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• 1997

가시오가피 종자는 채종직후 미분화 상태의 배로 발아를 위해서는 후숙이 필요하다. 가시오가피 종자의 후숙을 위하여 습윤층적처리한 후 미분화 배의 생장과 개갑특성을 조사한 결과는 다음과 같다. 1. 가시오가피의 내과피를 포함한 종자의 형태는 길이 7.1$\pm$0.9mm, 폭 3.0$\pm$0.3mm, 두께 1.47$\pm$0.12mm 정도이었으며 1,000 입중 18.5$\pm$1.9g 정도이었다. 2. 가시오가피 종자의 후숙전 0.30$\pm$0.06mm 정도이며 배장율은 .4.8%의 미분화 배로 층적처리 20일 전후에 배의 생장이 시작되었고 40일 전후에 배축과 자엽이 분화되었다. 3. 후숙기간과 배장율과는 높은 정의 상관(r=0.845)을 보였으며 배의 생장은 층적처리 후 60~80일 사이에 급격히 증가하였고 후숙 80일 이후에는 증가폭이 다소 둔화되었다. 4. 가시오가피 종자는 배가 어느 정도 생장하면 종피의 봉선이 터져 열개되는 개갑종자이었으며 배장율 60~70%에서 가장 높은 개갑빈도를 나타냈다. 5. 개갑율은 후숙 40일에 15.3%가 개갑되었고 60일 이후 개갑율이 급격히 증가되었으며 후숙 150일에 76.5%가 개갑되었다.