• Korean Journal of Microbiology
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• v.45 no.4
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• pp.300-305
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• 2009

We constructed the deletion mutants of fission yeast Schizosaccharomyces pombe spNab2 gene that is homologous to poly(A)-binding protein NAB2 in budding yeast Saccharomyces cerevisiae, which plays crucial roles in mRNA 3' end formation and mRNA export from nucleus into the cytoplasm. A null mutant in an $h^+$/ $h^+$ diploid strain was constructed by replacing the spNab2-coding region with an $ura4^+$ gene using one-step gene disruption method. Tetrad analysis showed that the spNab2 is not essential for vegetative growth and mRNA export. However, over-expression of spNab2 cause the severe growth defects and intensive accumulation of poly(A) RNA in the nucleus. Also, the spNab2-GFP fusions were localized mainly in the nucleus. These results suggest that spNab2 is also involved in mRNA export out of the nucleus.

• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.321-326
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• 1998

Two strains, each of Tremella fuciformis and Hypoxylon sp. were isolated and their mycelial properties were investigated. T. fuciformis produced yeast-like conidia and dikaryotic mycelia from white to yellow color. The diameter of the hyphae was $1.5\;to\;3.0\;{\mu}m$, and septa with clamp connections were present. Secondary mycelia with clamp connections could produce fruitbodies on sawdust medium when the environmental conditions were suitable for fructification. The symbiotic fungus, Hypoxylon sp. produced white feather-like mycelia. But the color of old mycelia was changed to light yellow or light brown and pigmented the culture medium from light brown to brown or very dark green. Generally it did not produce conidia, but in a special case it produced conidia of which color was yellow green to grass green and of which shape was sub-elliptical with the size of approximately $3\;to\;5\;{\mu}m$.

• Journal of ILASS-Korea
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• v.26 no.3
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• pp.127-134
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• 2021

Fire sprinkler initial spray was analyzed by Large eddy simulation (LES) and Volume of Fluid (VoF) integrated method. The IsoAdvector geometric VoF was used to identify the liquid-gas interface clearly even with the large Courant-Friedrichs-Lewy number. To reduce the computational costs, sector meshes and Adaptive Mesh Refinement up to level 3 were used. Base mesh size was 1 mm, which is roughly equivalent to the initial sprinkler droplet. Top surface radius of boss and deflector size were modified to investigate the effects of sprinkler head design on primary breakup process. When top surface radius of boss was increased, vertical liquid sheet was formed. This phenomenon reduced the sheet breakup radius, sheet thickness and velocity. Due to reduced liquid sheet thickness, a large amount of ligaments was created from the liquid sheet. As a result, there was a dramatic decrease in volume per surface area, indicating an increase in breakup process. Spray pattern viewed in radial direction also changed when top surface radius of boss increased. When top surface radius of boss was increased, a T-shaped pattern was observed while a V-shaped pattern was observed in all other cases. When the deflector size increases, the spray pattern remains V-shaped, even if the top surface radius of boss increased. Further studies on promoting atomization of the water supplied to the lower part of the sprinkler head in the T-shape pattern should be conducted.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.76-80
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• 1983

In order to investigate the effect of boron and phosphorus for reduction of cold injury of rice, this experiment was undertaken by pot trial. Two levels of phosphorus and 6 levels of boron were applied once at the three stages such as tillering, panicle formation and meiosis stage. Cold water was irrigated to maintain cool temperature ranging 15 to $18^{\circ}C$ from panicle formation stage. It was shown a tendency that three to seven days of early heading were resulted by the 3, 5 and 10kg of boron application per 10 are. The ripening ratio and physiological root activity was rather slightly increased in the above boron levels.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.2147-2159
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• 1991

The effects of principal dimensions of internal mixing twin-fluid atomized and operating conditions on the atomizing characteristics are experimentally investigated. The tests are conducted over the wide range of air/liquid ratio to predict influences of the diameter and length of nozzle, contacting angle between air and liquid in the mixing chamber, and air orifice diameter on the mean drop size(SMD), spray angle, distribution of drop size, and spray dispersion, And also, initial distribution of liquid column by air stream within the mixing chamber are observed through the transparent nozzles. A He-Ne laser particle sizer(MALVERN Model 2604) was used to measure the Sauter.s mean diameter( $D_{321}$) and droplet sizes distribution. In this experiment the air/liquid ratio, mixing length and nozzle diameter have a great influence on SMD, spray angle, droplet sizes distribution and spray dispersion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.429-434
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• 1997

The most typical morphological characteristics of seeds of eight species in Umbelliferae are summarized as follows: 1. The common characteristics of seeds in Umbelliferae were bi-partite fruits, compound of 2-seeds, (fruitlet) oil canals and funiculus or carpaphore. 2. Seed shape of Umbelliferae were oblong or elliptic and ovate; seed colors were yellow, pale yellow or brown, dark brown or black. 3. Seed size ranged from 2 to 7mm in length and 2∼5mm in width. Angelica dahurica bore the largest seed while Ligusticum acutilobum showed the smallest. The 1000-seed weight ranged from 1. 7g in Bupleurum falcatum to 3.9g in Angelica gigas.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.149-152
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• 2009

Spray characteristic parameters such as droplet mean velocity, diameter, and volume flux are measured at various locations of spray in order to investigate the evolutionary feature of droplets exiting from a direct-injection type thruster nozzle-orifice. The experimental results indicate that the large droplets with high velocity at the center of upstream are broken-up into smaller droplets with low velocity due to their continuous momentum loss to surrounding air along with spray evolution toward downstream. Also it is found that the high volume flux expands its distribution in radial direction as a results of spray spreading and dispersion.

• Journal of the korean Society of Automotive Engineers
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• v.5 no.4
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• pp.10-16
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• 1983

액체의 미립화는 기계산업분야 뿐만 아니라, 농약살포, 화학 공학의 분무건조, 반응의 촉진, 분 체제조, 식품공업 등 폭넓게 이용되며 또한 각분야에서 그 필요성이 강조되고 있다. 특히 기계 산업분야에서는 액체연료의 분무연소(boiler, gas turbine, 자동차용engine등) 원자로 노심의 spray cooling, spray drying, spray painting 등 그 이용도는 날로 증가되는 추세에 있다. 액체를 미 립화하는 이유는 각각의 분야나 사용하는 목적에 따라 다르지만, 대별하면 다음과 같다. (1) 액체의 단위 체적당 표면적을 증대시키기 위하여 (2) 직경이 작은 입자의 필요성 (3) 균일한 입경의 액적군을 얻기 위하여 등을 들 수 있다. 액체의 미립화에 대한 요구는 산업의 발당, 대기오염, 생energy 등의 문제가 중요시됨에 따라 다양화되고 있다. 따라서 응용면에서는 atomizer의 성능개선과 설계법, 새로운 미립화방법, 상업에의 분무이용기술, 분무계측법 등의 개발이 필요하게 된다. 액체미립화에서 취급하는 사항은 그 내용에 따라 다음과 같이 분류된다. (1) 액체의 미립화기구 : 기액계면의 불안정성과 분열기구에 관한 것으로, 액체형상으로써 액주, 액막 및 액적으로 나눌 수 있다. (2) 액체의 미립화 방법과 특성 : energy의 종유와 부가방식에 따랄 나누어진다. (3) 합체, 분산, 증발 등 분무의 운동이나 열적거동 (4) 분무입경이나 운동의 계측법과 특성도시 (5) 액체미립화의 각종응용 본보에서는 상기의 각 항목중, 특히 액체의 미립화방법과 분무특성에 대해서만 말하기로 한다.

• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.322-325
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• 2011

본 연구는 넓은잎 딱총나무 잎으로부터 유도된 캘러스의 형태학적 특성과 효능에 관한 것이다. 딱총나무에서 유도된 캘러스 내의 세포들을 촬영한 표면주사현미경 사진에서 분열능이 높은 세포의 특성을 보여주었다. 유도된 넓은잎 딱총나무 캘러스를 생물반응기 내에서 배양시켜 얻은 딱총나무 식물세포배양 추출물은 DPPH 제거 및 $PPAR{\alpha}$ 활성 실험결과에서 자유라디컬 제거능 및 항염증 효능이 높게 나타났다. 이러한 딱총나무 캘러스 세포 배양 추출물은 화장품의 항노화 신소재로서 응용될 수 있다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.143-148
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• 2012

This study is an investigation on macroscopic spray behavior of nonimpinging-type injector equipped on the hydrazine thruster under development. An electron microscope is employed for the acceptance examination of injector orifice. Initial performance characteristics and spray behavior of injector are observed through the instantaneous spray images which are captured by high speed camera and Schlieren method with varying injection pressures. The injector performance is scrutinized by the velocity along with penetration length of spray and categorized by dimensionless parameters. It is confirmed that there exist varying characteristics related to the spray breakup caused by fabrication errors of injector-orifices. Unexpected spray behavior, which needs to be reexamined, is grasped at specific pressure level, as well.