• 한국작물학회지
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• 제51권spc1호
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• pp.35-41
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• 2006

쌀 품질의 고급화를 위한 벼 수확 후 관리기술체계를 확립하기 위하여 벼 수확을 대형포대 및 콤바인포대로 수확한 후 수분함량 별 야적기간 연장에 따른 쌀 품위 및 품질변화에 미치는 영향을 조사였다. 수확당일 수확시간에 따른 정조의 수분함량은 $23.7{\sim}28.8%$로 수확시간이 늦어질수록 낮았고, 수확 후 건조지연에 따른 정조의 외관변화는 저장포대가 대형인 경우 3일째 정조의 색깔이 변하고 악취가 심하게 발생하였으며 콤바인포대는 4일째부터 색깔이 변하고 악취가 발생하였다. 포대내부의 온도변화는 대형포대는 저장기간이 길어질수록 그리고 수분함량이 높을수록 증가되는 폭이 컸으나 콤바인포대는 수확당시 수분함량에 따라 일정한 비율로 증가되는 경향이었다. 대형포대에 저장된 정조의 수분함량은 저장 2일째부터 증가되었고 수분함량이 높을수록 증가폭이 컸으나 콤바인포대의 경우는 수확 시 수분함량이 적은 경우 약간 감소하는 경향이고 높은 경우는 약간 증가되는 경향이었다. 수확 후 건조가 지연될수록 단백질, 아밀로스함량은 차이가 없으나 지방산은 증가되었고 대형포대가 콤바인포대에 저장된 정조보다 지방산 증가폭이 컸으며 수확 후 건조지연일수나 벼 수확 시 수분함량이 높을수록 현미의 완전미율은 감소되고 청미와 피해립율이 증가되었으며 백미품위 역시 비슷한 경향이었다. 따라서 미질저하를 최소화 할 수 있는 포대종류별 건조지연 한계기는 대형포대가 벼 수확 후 $1{\sim}2$일 이내, 콤바인포대는 $2{\sim}3$일 이내로 추정되었다.

• 한국작물학회지
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• 제50권6호
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• pp.406-410
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• 2005

본 실험은 개갑된 인삼종자를 안전하게 장기보존하고, 또한 이를 효율적으로 발아시키기 위하여 인삼종자의 건조 저항성 및 동결보존을 위한 적정 수분함량을 분석하고, 배 발육과 발아에 관여하는 온도와 호르몬의 상호작용 효과에 대하여 조사하였으며, 이에 대한 결과는 다음과 같다. 1. 30일 후의 초기 발아율은 $GA_3$와 BA 등 생장조절제 처리 후 $5^{\circ}C$와 $10^{\circ}C$에서 발아시킬 경우에만 $50\%$ 이상으로 높아졌다. 70일 후의 발아율은 생장조절제의 처리와 상관없이 $5^{\circ}C$와 $10^{\circ}C$에서 모두 $90\%$ 이상으로 높게 나타났고, $15^{\circ}C$에서도 생장조절제 처리구에서는 일부 발아하였다. 2. 개갑 인삼 종자를 무균상 송풍구와 종자건조실에서 건조시킬 경우 각각 12시간(종실 수분함량 $10.6\%$) 및 3일($6.1\%$) 까지는 내과피와 종실간에 수분함량에 차이를 보이면서 급속히 건조되다가 이후 서서히 건조되었다. 3. 무균상에서 0${\~}$l8시간 동안 건조된 종자(수분함량 $57.9{\~}8.7\%$)는 $95\%$ 이상이 발아하였으나, 30시간 건조된 종자($7.2\%$)는 발아율이 $85\%$로 감소하였다. 건조된 인삼종자를 액체질소에 저장 후 발아율을 조사한 바, 12${\~}$30시간 건조($10.6{\~}7.2\%$)된 종자는 $90\%$ 이상이 발아하였다. 4. 건조실에서 건조된 인삼종자는 0${\~}$2일 동안 건조($57.9{\~}9.0\%$)하였을 때 $90\%$이상이 발아하였으나, 6일 건조($3.8\%$)된 종자는 발아율이 $30\%$ 이하로 대폭 감소하였다. 동결보존 후의 발아율은 2일 건조 종자($9.0\%$)만이 $90.5\%$의 높은 발아율을 보였다. 5. 최적수분함량에서 두 건조방법간에 동결보존 전후의 발아율에 유의한 차이가 없었으며, 건조 장해를 받지 않으면서도 동시에 동결장해를 회피할 수 있는 적정 수분함량범위는 $8{\~}l0\%$였다.

• 한국제4기학회지
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• 제18권2호통권23호
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• pp.17-17
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• 2004

The Pleistocene lake level and climate development is described by proxies from sediment, pollen and diatom records in Mongolia and Northwest-China. It could be proved that higher lake levels seem to have existed during the old and mid Pleistocene period interpreted on the base of geomorphological and sedimentological reords. They are dated in a relativ time scale. The lake basins are filled up to 300 m by limnic deposits, which foused on a constant water balance of more than 700.000 years. Late Glacial and Holocene lake level fluctuations and climate changes can be proved by biostratigraphic records pointing to dry and wet phases. Only for the youngest history desiccation of some lakes are related to human impact.

• 한국환경과학회지
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• 제11권6호
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• pp.529-535
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• 2002

Efffcts of physico-chemical factors on the zonation and vertical distribution of benthic microalgal communities in the tidal flats of Youngkwang and Canaiin, Korea, were studied. Concentrations of nutrients were low throughout the study period. A 38 species of benthic microaigae was identified. Most of the algae were pennate diatoms with small size. Cell numbers at silty sediments were higher than sandy sediments, and showed high patchy distribution. Zonal distributions of benthic microalgae showed higher variation from silty sediment than sandy sediments. Benthic microalgae showed vertical migration within the upper few mm of sediment with periodicity closely related to tidal cycles. Maximum cells were observed from 0 mm depth both sandy and silty sediments. Cells of benthic microalgae in the 1 - 2 mm depth decreased after desiccation of sediments. The variation of cells was higher at sandy sediments than silty sediments. Cell numbers of benthic microalgae showed no positive relationships with pH and nutrinets except NH$_4$-N.

• BMB Reports
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• 제29권3호
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• pp.248-252
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• 1996

The epidermal organ of the leech contains a complex glycoprotein molecule of mucus. The mucus excreted from annelids plays Significant role in protection against desiccation and parasites. Mucus from the Korean native leech, H. nipponia, was investigated for biochemical characteristics for possible development of biomaterials of cosmetic and pharmaceutical agents. The leech skin mucus was heavily glycosylated mucin-like protein with a high molecular weight comprised 80% carbohydrate and 20% protein. Threonine, serine, and glycine were the major components of the isolated protein and these accounted for 50% of total amino acids. The carbohydrate portion contained glucosamine, galactosamine. galactose, glucose. mannose and sialic acid in oligosaccharide form linked with threonine and serine residues of the glycoprotein.

• The Korean Journal of Ecology
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• 제8권3호
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• pp.141-146
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• 1985

Colonization ability was studied with Lemna paucicostata and Spirodela polyrhiza. Colonization ability of each species was defind as its ability to; (1) tolerate to desiccation, (2) multiplicate and spread in the new habitat, (3) inhibit the other species competitively. Lemna paucicostata was inferior to Spirodela polyrhiza in ability (1), but superior to Spirodela polyrhiza in abilities (2) and (3). Whenever lemna paucicostata and Spirodela polyrhiza are colonized recently, only these three abilities can not explain which species is better colonist. Even short unsuitable periods would eliminate a species, with time lag occurring before recolonization. This would result in a discontinuous of the species concerned.

• Computers and Concrete
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• 제13권3호
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• pp.361-375
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• 2014

The moisture transport in underground concrete was experimentally investigated and the nonlinear model of moisture transport considering the effects of water diffusion, hydration of cementicious materials and water permeability was proposed. The consumed moisture content by self-desiccation could be firstly calculated according to evolved hydration degree of cement and mineral admixtures. Furthermore, the finite differential method was adopted to solve the moisture transport model by linearizing the nonlinear moisture diffusion coefficient. The comparison between experimental and calculated results showed a good agreement, which indicated that the proposed moisture model could be used to predict moisture content evolution in underground concrete members with drying-wetting boundaries.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.789-792
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• 2005

Development of high-strength concrete and improved durability has brought new opportunities to the construction industry. However, some attention was given to characteristics of such concrete, in particular with respect to their cracking sensitivity. It has been argued and demonstrated experimentally that a low water/cement ratio concrete undergoes shrinkage due to self-desiccation. This so-called autogenous shrinkage cracking is a major concern for concrete durability. One possible method to reduce cracking due to autogenous shrinkage is the addition of expansive additive. Tests conducted by many researches have shown the beneficial effects of addition of expansive for reducing the risk of shrinkage-introduced cracking. This paper aimed at forecasting deformation of high strength cement paste with expansive additive for early age.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.469-470
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• 2010

The high-strength concrete(HSC) compared to normal concrete represents higher autogenous shrinkage due to lower water-to-binder ratio(W/B) and supplementaries, fly ash(FA) and granulated blast-furnace slag(BFS), etc. The potential of early age cracking which reduces durability of concrete structures is normally influenced by autogenous shrinkage and degree of restraint. Therefore, this paper studies on the evaluation of the characteristics of autogenous shrinkage for HSC, ultra-high-strength concrete(UHSC) containing admixtures by experimental test and the test results are compared with existed prediction models.

• Animal cells and systems
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• 제16권5호
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• pp.425-430
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• 2012

The southwestern Australian frog Crinia georgiana (Anura; Myobatrachidae) inhabits ephemeral pools in which the tadpoles often face desiccation. Under these conditions selection on tadpoles can be severe and can directly affect fitness during the aquatic as well as the terrestrial developmental stages. A quantitative genetic study using a half-sib breeding design was conducted to understand the genetic effects on larval life-history traits. We found no significant additive genetic variance in any of larval traits. Except for hatching period, heritability estimates based on females were high in egg size, larval period, snout-vent length, and weight at metamorphosis, suggesting non-additive genetic effects. These results indicate that any response to selection during hatching and larval periods should be predominately governed by non-additive genetic effects in C. georgiana.