• 생명과학회지
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• 제16권6호
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• pp.898-903
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• 2006

한국내 분포하는 장미과의 솜양지꽃(Potentilla discolor Bunge) 15집단에 대한 19 알로자임 대립유전자좌위에서 유전적 다양성과 집단구조를 분석하였다. 조사한 좌위에 대해 약 73.7%가 다형성을 나타내었다. 종과 집단 수준에서 유전적 다양도는 각각 0.215, 0.196이었으며, 집단간 분화정도는 낮았다$(G_{ST}\;=\;0.069)$. 전체 유전적 다양성은 0${\sim}$0.656이며 평균 0.292였다. 유전적 다양도 중 집단내 변이는 높았다$(H_{S}\;=\;0.274)$. 전체 유전적 변이에서 집단간 차이는 Pgm-2에서 0.010, Pgd-2에서 0.261로 평균 0.069였다. 이는 전체 알로자임 변이 중 약 6.9%가 집단간에 있음을 의미한다. 솜양지꽃의 특성으로 광범위한 분포, 다년생 초본, 여러 세대의 존재 등이 높은 유전적 다양성을 나타내는데 기여하는 것으로 설명된다. 조사한 솜양지꽃 집단에서 세대당 이주하는 개체수는 3.36으로 평가되었다.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제5권1호
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• pp.35-45
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• 2001

In this paper we point out an Ostrowski type inequality for the Riemann-Stieltjes integral ${\int}_a^b$ f (t) du (t), where f is of p-H-$H{\ddot{o}}lder$ type on [a,b], and u is of bounded variation on [a,b]. Applications for the approximation problem of the Riemann-Stieltjes integral in terms of Riemann-Stieltjes sums are also given.

• 대한화학회지
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• 제23권5호
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• pp.320-324
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• 1979

Halobacterium halobium으로부터 분리 정제된 퍼플멤브레인을 7.5% 폴리아크릴아미드겔에 혼합시켰다. 이 겔을 사용하여 pH 변화에 따른 흡수 스펙트라와 원편광 이색성스펙트라를 얻었다. pH 7.0에서 보여준 이들 스펙트라의 성질들은 수용액내에 부유하고 있는 퍼플멤브레인으로부터 얻은 것들과 동일하였다. pH 2.7에서는 최대흡광도를 605nm에서 나타내었으며 pH 0.8에서는 565nm에서 보여주었다. 광에 노출되지 않았던 겔의 경우는 광에 노출되었던 겔과는 달리 등흡광점을 보여주었다. pH 2.7과 pH 0.8에서 측정한 원편광 이색성스펙트라는 pH 7.0에서 보여준 bilobed형을 유지하였으며 UV영역에서 분자편광도나 스펙트라의 모양도 pH에 따라 큰 영향을 받지 않았다. pH 2.7에서 생성된 bR605acid 가 퍼플멤브레인의 정상 광화학 순환기 중간 생성물인 $O^{640}$와 유사한 성질을 가진종이 아닐까 추측된다.

• 한국세라믹학회지
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• 제49권5호
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• pp.442-447
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• 2012

This study investigated on the early hydration and physical characteristics of BFS by pH variation. NaOH solution was used as a pH activator. In the range from pH 12 to pH 14, Experiment was compared the hydration propertied of OPC(Ordinary Portland Cement) and BFS(Blast Furnace BFS) and BFS containing 2 wt% of gypsum. It was found that CAH(Calcium Aluminate Hydrates) phases and CSH(Calcium Silicate Hydrates) phases were formed during the early hydration of BFS, and that CAH phases, CSH phases and ettringites were formed during the early hydration of BFS containing 2 wt% of gypsum. Furthermore, early hydration of BFS and BFS containing 2 wt% of gypsum were faster then OPC at pH 14, and the 1 day compressive strength of BFS increased by approximately 30% compared to OPC, and BFS containing 2 wt% of gypsum also increased by approximately 40% compared to OPC.

• Bulletin of the Korean Chemical Society
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• 제21권12호
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• pp.1217-1221
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• 2000

L-alanine dehydrogenase from Bacillus subtilis exhibits allosteric kinetic properties in the presence of $ZN^{2+}$. $ZN^{2+}$ induces the binding of substrate (L-alanine) to be cooperative at pH 8.0. The effect of pH variation between pH 7.0 and pH 10.0 on the inhibition by $ZN^{2+}$ correlates with the pH effect on the $K_m$ values for L-alanine within these pH range indicating that $ZN^{2+}$ and substrate compete for the same site. No such cooperativity is induced by $ZN^{2+}$ when the reaction is carried out at pH 10. At this higher pH, $ZN^{2+}$ binds with the enzyme with lower affinity and noncompetitive with respect to L-alanine. Inhibition of L-alanine dehydrogenase by $ZN^{2+}$ depends on the ionic strength. Increase in KCI concentration reduced the inhibition, but allosteric property in $ZN^{2+}$ binding is conserved. A model for the regulatory mechanism of L-alanine dehydrogenase as a noncooperative substrate-cooperative cofactor allosteric enzyme, which is compatible in both concerted and the sequential allosteric mechanism, is proposed.

• 한국세라믹학회지
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• 제50권4호
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• pp.294-300
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• 2013

The effect of chemical treatments of porous silicon in organic solvents on its nanostructural and optical features was investigated. When the porous Si was dipped in the organic solvent with various PH values, the morphological, chemical, and structural properties of the porous silicon was sensitively affected by the chemical conditions of the solvents. The size of silicon nanocrystallites in the porous silicon decreased from 5.4 to 3.1 nm with increasing pH values from 1 to 14. After the samples were dipped in the organic solvents, the Si-O-H bonding intensity was increased while that of Si-H bonding decreased. Photoluminescence peaks shifted to a shorter wavelength region in the range of 583 to 735 nm as the pH value increased. PL intensity was affected by the size as well as the volume fraction of the nanocrystalline silicon in the porous silicon.

• 한국지구과학회:학술대회논문집
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• 한국지구과학회 2005년도 춘계학술발표회 논문집
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• pp.115-125
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• 2005

Carbon isotopic composition of a stream (Odaecheon Stream) monitored over 7 months from July 2004 to January 2005 in Gangweon Province ranges from -9.24 to -4.69‰. Strong negative correlation between ${\delta}^{13}C_{DIC}$ and water temperature suggests that temperature is a dominant factor controlling ${\delta}^{13}C_{DIC}$ in the Odaecheon Stream. The variation pattern of ${\delta}^{13}C_{DIC}$ was thought to be caused by fractionation of C isotope between stream water and atmosphere and more fractionation at reduced temperature. More fractionation of C isotope between stream water and atmosphere at reduced temperature resulted in increase of ${\delta}^{13}C_{DIC}$ of stream water in winter compared to summer. Photosynthesis and respiration of aqueous biota seem to affect little in ${\delta}^{13}C_{DIC}$ as indicated by little variation of dissolved oxygen and reverse variation pattern of Eh in the stream and scarce aqueous biota in stream water. pH seems to be controlled by $CO_2{2}$ exchange between stream water and atmosphere. During summer more $CO_2{2}$ exchange between stream water and atmosphere resulted in decrease in pH value.

• 생명과학회지
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• 제17권7호통권87호
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• pp.877-881
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• 2007

전분 젤 전기영동을 사용하여 한국내 분포하는 세잎양지꽃 8개 집단에서 유전적 다양성과 집단구조를 평가하였다. 종수준에서 효소내 다형현상을 나타내는 대립유전자좌위는 68.4%였다. 집단 수준에서 유전적 다양도는 유사한 생활사를 가진 초본류의 평균값에 비해 높았다. 전체 유전적 다양도는 조사한 8개 집단에 대해 0.190과 0.584사이에 있었으며 평균은 0.371이였다. 집단내 유전적 다양도는 0.354였다. 집단간 분화정도는 비교적 낮았다($G_{ST}$ = 0.065). 고정지수 분석 결과 많은 집단과 대립유전자좌위에서 이형접합체의 결핍이 있었다. 이는 세잎양지꽃은 줄기에서 꽃을 형성하여 종자번식을 하는 타가수분방식과 분지하여 새로운 개체를 형성하는 영양번식을 영위할 수 있는 다양한 번식법을 가지고 있는 클론 식물의 특성에 기인한 것으로 사료된다. 따라서 같은 집단에서 다양한 세대의 존재하여 내교잡(inbreeding)이 발생한 것으로 볼 수 있다.

• 대한화학회지
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• 제13권2호
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• pp.187-193
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• 1969

As part of an extensive program on the microbiological oxidation of hydrocarbons, reaction conditions and nutrients consumption of candida lipolytica grown on alkane as carbon source were studied. For optimum growth of yeast, the conditions of pH 5, temperature $30^{\circ}C$, carbon number $C_{16}$& $C_{18}$aeration 25.6 1/l/hr, agitation 3000 r.p.m., hydrocarbon concentration 10% were obtained. Carbon and nitrogen balance related to these conditions were also investigated. In the course of this investigation, some significant effects of pH and carbon number of hydrocarbon variation were observed.

• 한국자원식물학회지
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• 제19권6호
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• pp.677-679
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• 2006

The objectives of this study were to examine the genetic variation of 20-year-old tree height and to estimate heritabilities and genetic gains of Korean white pine. Analysis of variance showed that families and family x block interaction had the significant (p=0.01) effects on tree height. However, family variation appears to be much greater than the variation due to family x block interaction. Individual tree heritability was higher ($h_I^2=0.73$) than family heritability, ($h_F^2=0.83$) therefore, combined selection showed the largest genetic gain (17.76%) in a given equal intensity of selection.