• 충청수학회지
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• 제29권2호
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• pp.221-227
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• 2016

This paper will discuss the huge change of b - separated, b - connectedness, b - disconnectedness and their applications when the definition of b - separated and b - connectedness are small changed.

• Journal of Magnetics
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• 제12권3호
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• pp.93-96
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• 2007

We investigated the electronic structure and magnetic properties of zinc-blende CrP/SrBi interface by using the all-electron full-potential linearized augmented plane wave method within the generalized gradient approximation. It is found that the half-metallicity is destroyed when the two half-metals are in contact. Magnetic moments of the atoms forming the supercell differ considerably from the respective values obtained for the bulk structures of the two materials. Cr atoms being and not being in contact with Bi atoms have magnetic moment 3.43 and $2.69{\mu}_B$, respectively. Bi atoms lose their majority electrons which results in their negative polarization. Alkaline Sr atoms are very weakly negatively polarized. The spin distribution within the supercell is such that well separated regions of positive and negative polarization are seen, especially around the layer of P atoms being in contact with the layer of Sr atoms.

• Bulletin of the Korean Chemical Society
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• 제5권4호
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• pp.154-158
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• 1984

In order to characterize the permeability of small unilamellar vesicles (SUV), efflux of 6-carboxyfluorescein (6-CF) from the vesicles was monitored spectrophotofluorometrically. Since the entrapped highly quenched 6-CF (200 mM) became fluorescent upon release from the vesicles, the 6-CF could be used as an efflux probe. SUV containing entrapped 6-CF was prepared from egg phosphatidylcholine and separated by gel filtration on Sepharose 4B. Observed change of relative fluorescent intensity with time was sigmoidal. From this curve, the parameter of permeability was determined either by half-time or a released amount per unit time from the initial slope. Half-time of efflux of prepared SUV having 302 ng phospholipid/ml in 10 mM Tris-HCl buffer pH 7.4 was 21.0 min at $37{\circ}C$. Various factors which could affect the half-time were examined including temperature, pH, salt, and vesicle concentration. In particular the effect of vesicle concentration on the efflux revealed that the permeability can be a function of the concentration.

• 분석과학
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• 제10권3호
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• pp.168-178
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• 1997

기체 크로마토그래피법을 이용하여 제초제인 ethalfluralin의 잔류분석을 위한 최적 측정 조건을 구하고, 토양에서의 잔류량과 반감기를 조사하였다. 토양시료를 methanol과 dichloromethane으로 추출하여 농축하였다. Toluene으로 다시 녹이고, cyanosilica gel 카트리지로 분리하여 전자포착형 검출기가 장착된 기체 크로마토그래프(GC-ECD)로 분석하였다. 0.1과 1.0ppm의 표준물을 첨가하였을 때, 92.8~101.2%의 회수율을 얻었으며, 검출한계는 0.004ppm이었다. Ethalfluraline의 반감기는 토양 (A)의 경우에는 실내에서 35일, 야외에서 7.2일이었으며, 토양 (B)의 경우에는 실내에서 45일, 야외에서 9.7일이었다.

• 환경생물
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• 제39권4호
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• pp.423-434
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• 2021

Two new free-living marine nematodes of the genus Belbolla Andrássy, 1973 belonging to family Enchelidiidae are newly described based on specimens obtained from a shallow subtidal sediment of the western and southern outermost islands of Korea. Belbolla koreensis sp. nov. differs from other species of the genus by the combination of the following characteristics: longer body length (3,080-3,462 ㎛ long), eight oesophageal bulbs in the posterior region of pharynx, well-developed two winged precloacal supplements (anterior precloacal supplement slightly longer than posterior one: 47-59 ㎛ vs. 43-46 ㎛ long), strongly arcuated, very thick, L-shaped spicule (122-127 ㎛ long, 1.7-1.9 anal body diameter(a.b.d.) long) with three separated blunt distal tips, and well-developed relatively long cylindrical shaped gubernacular apophysis with blunt teeth covering two thirds of the dorsal margin (57-58 ㎛ long, 0.8-0.9 a.b.d. long). Belbolla hoonsooi sp. nov. is characterized by the following combination of characteristics: longer body length (3,494 ㎛ long), eight oesophageal bulbs in the posterior region of pharynx, well-developed two winged precloacal supplements (anterior precloacal supplement slightly longer than posterior one: 43 ㎛ vs. 36 ㎛ long), strongly arcuated, L-shaped spicule (119 ㎛ long, 1.5 a.b.d. long) with three separated blunt distal tip, and well-developed relatively long inverted triangle shaped gubernacular apophysis with blunt teeth covering half of the dorsal margin (45 ㎛ long, 0.6 a.b.d. long). Detailed morphological characteristics and illustrations of two new Belbolla nematodes from the Korean seawaters were provided by differential interference contrast microscopy. Comparative tables on biogeographical and morphological characteristics of Belbolla species are also provided herein.

• 한국의류학회지
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• 제28권8호
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• pp.1175-1185
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• 2004

This study evaluated thermo-physiological and subjective properties of improved disposable coveralls for railroad carriage maintenance through climatic chamber trials and a filed study. Subjects wore five kinds of disposable coveralls (Type A: a disposable coverall on the market, Type B: a coverall with an improved hood and size-adjustable design, Type C: a coverall with a portable hood, Type D: a coverall with small holes for ventilation, Type E: a sleeveless coverall, Type F: a separated type of coverall with half sleeves) The air temperature in the climatic chamber was set in 9$^{\circ}C$ and 30$^{\circ}C$ For each condition, subjects simulated the railroad work for 120min. and rectal temperature, skin temperatures, clothing microclimate and subjective sensations were measured. The results of chamber trials showed rectal temperature and clothing microclimate did not display significant differences by clothing type. In 30$^{\circ}C$ air temperature, mean skin temperature was higher in Type E and Type F than in Type A(p＜0.05) but between the improved coveralls(B-F), we could not find any significant difference. In the case of thermal comfort, the most preferred types were Type B and Type C in 9$^{\circ}C$ and Type F in 30$^{\circ}C$. All subjects felt more comfortable in the improved coveralls than in coveralls of the market (Type A). In field study, workers preferred Type B, Type C and Type F to Type A but the most favorite type differed by the specific type of work. Especially, workers were dissatisfied that Type D tore easily due to lots of small holes around the armpits and Type I did not protect workers＇ shoulder and arms from oil contamination. According to the climatic chamber trials and field study, the most effective coveralls were Type B and Type C for winter and Type F for summer.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1568-1572
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• 2007

To develop a natural fungicide against Botrytis cinerea and Colletotrichum gloeosporioides, a total of 25 essential oils were tested for their fumigant activity against post-harvest pathogens. The vaporous phases of oils were treated to each fungus on potato dextrose agar medium in half-plate separated Petri plates at $10\;{\mu}g$ per plate. The essential oil of Illicium verum strongly inhibited the mycelial growth of both B. cinerea and C. gloeosporioides by over 90%. On the other hand, the essential oil of Schizonepeta tenuifolia showed inhibitory activity against mycelial growth of only B. cinerea by over 90%. Gas chromatography-mass spectrometry and bioassay indicated trans-anethole in I. verum and menthone in S. tenuifolia as a major antifungal constituent. The essential oils of I. verum and S. tenuifolia and their major constituents could be used to manage post-harvest diseases caused by B. cinerea and C. gloeosporioides.

• Biomolecules & Therapeutics
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• 제6권3호
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• pp.276-282
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• 1998

Retinoids regulate a wide variety of biological processes such as cellular proliferation and differentiation in many cell types. They have also shown to stimulate replication of several viruses including human cytomegalovirus (CMV). Retinoid signalling pathway involves two distinct subfamilies of nuclear receptors, retinoic acid receptors (RARs) and retinoid X receptors (RXRs) that bind to specific retinoic acid response elements (RAREs) in the promoter regions of retinoid-target genes. Here, we characterized RAREs in the regulatory regions of the CMV and of the hepatitis B vi.us (HBV). The viral RAREs, i.e., CMV-RARE and HBV-RARE, are composed of two consensus RARE half-sites (A/GGGTCA) arranged as a direct repeat separated by 5-bp and 1-bp, respectively. The RAREs were activated by both RAR/RXR heterodimers and RXR homodimers in transient transfection experiments. We also found that COUP-TF$\alpha$ (chicken ovalbumin upstream promoter-transcription factor u) and COUP-TF$\beta$ repressed the retinoid response of the viral elements. Further we demonstrated that previously known retinoid antagonist, SRI 1330, repressed retinoid-induced transactivation of the CMV-RARE. These results implicate Vitamin A, it's nuclear receptors and COUP-TFs as important regulators of the CMV and HBV pathogenesis and the SRl1330 as potential negative modulator of such retinoid-dependent processes.

• 수산해양기술연구
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• 제31권3호
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• pp.296-305
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• 1995

보일러 및 연소로 등에서의 부유체 환경에서 입자와 벽면 사이의 열전달 현상을 규명하기 위한 수치적인 모델링을 행하였다. 본 연구에서는 벽면에 수직 충돌하는 입자에 의한 열전달 현상을 알아보기 위해 2차원 모델을 사용하였다. 입자표면에서 단열된 경계조건과 등온의 경계조건을 사용한 결과를 비교함으로써, 입자가 벽면에 충돌할 때 유체를 매개로한 전도와 입자에 의해 야기된 대류 현상을 비교할 수 있었다. 계산 결과, 입자가 벽면에 충돌하기 직전에는 입자 크기의 반정도의 거리에 도달할 때까지는 입자의 영향이 별로 없고, 충돌하고 난 후에 영향이 많았다. 또한, Pe 수가 작을 때는 유체를 매개로 한 전도가 지배적이며, Pe 수가 증가할수록 야기된 대류의 효과가 점차 증가하였다

• 조명전기설비학회논문지
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• 제13권4호
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• pp.7-13
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• 1999

본 연구는 의복디자인에 있어 색채적용에 도움이 되는 자료를 얻고자 1차색의 지각범위에 대하여 여대생 29명을 대상으로 실험을 하였다. 실험기간은 1998년 7월∼10월이다. 그 결과는 다음과 같다. 1) 30[%] 이상의 피험자가 지각한 지각범위 형태는 빨강에 대해서는 표준색 5R 4/14를 중심으로 5R 4/12, 5R 4/10, 5R 5/14로 명도축보다 채도축의 범위가 더 넓다. 노랑의 지각범위 형태는 표준색 5Y 8/14를 중심으로 채도축의 범위가 더 넓다. 파랑의 지각범위 형태는 표준색 5B 4/10을 중심으로 명도 축의 범위가 넓다. 2) 색도도에서 보면 1명 이상의 지각범위는 빨강은 전체 범위의 3/4에 걸쳐 넓게 분포하며, x축 선상으로 쭉 뻗어 있다. 노랑은 전체의 약 1/2에 걸쳐 분포하고 있으며, 전체가 연결되어 있지 않고 소수가 분리된 형태를 가진다. 파랑은 전체의 약 2/3에 걸쳐 분포하고 있으며, 그 선 상으로 늘어진 모든 색표가 포함되어 있다. 결론적으로 빨강의 지각범위는 상당히 넓게 분포되어 있으며, 피험자간의 공통성은 비교적 높으며, 노랑의 지각범위는 중간정도의 범위에 분포되어 있으며 피험자간의 공통성은 낮다. 또한 파랑의 지가범위는 약간 넓은 범위에 분포되어 있으며 피험자간의 공통성은 높다고 말할 수 있다.