• Journal of Life Science
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• v.12 no.6
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• pp.740-744
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• 2002

This experiment was conducted to clarify the effects of physiological properties in culture media on the proliferation and the acclimation of bulblets of several kinds of lilies cultured in vitro. Proliferation rate of bulblets from bulblet of Oriental hybrid ‘Marco Polo’, ‘Casa Blanca’ and Asiatic hybrid ‘Jolanda’ was higher in solid MS media compared with bulblets from scale Acclimation rate of regenerated bulblets was high in solid media which was pre-cultured in vitro, compared with liquid media. Sprouting rate of bulblets from bulblet was higher than bulblets from scale.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.197-201
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• 2004

Shoot clusters were induced from bulb scales of Lilium longiflorum 'Geogia', and proliferated on medium containing 0.5 mg/L BA and 0.5 mg/L IAA. Thereafter, these shoot clusters were cultured in 5 L air-lift bioreactors to form and grow normal bulblets. Number of bulblets increased on medium with 30 g/L sucrose, but growth of bulblets was effective on medium with 60 g/L sucrose. The number of bulblets from shoot clusters had no differences, though bulblet growth was very effective on medium with between full and double strength of MS salts. The inoculation of 100 g shoot clusters as a cultural material was suitable for formation and growth of bulblets in 5 L bioreactors. Air-lift type was more effective for the formation and growth of bulblets than that in ebb and flood one, and 200∼300 mL$.$min$^{-1}$ injection of air was suitable in growth of bulblets.

• Journal of Plant Biotechnology
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• v.29 no.1
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• pp.19-23
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• 2002

This experiment was conducted to micropropagate bulblets via shoot cluster formation and massproduce normal bulblets from the sections of proliferated shoot clusters in Lilium asiatic hybrid 'Hae Hwa'. The induction of shoot clusters from the culture of bulblet sections was more effective than that of bulb scales on MS medium with 1.0 mg/L BA and 0.5 mg/L IAA. Proliferation of shoot clusters from the formed shoot cluster sections was the most favorable on medium containing 5.0 mg/L BA and 0.5 mg/L IAA. The formation and the growth of bulblets from shoot cluster sections were achieved effectively on medium with 60∼90 g/L sucrose. The leaves derived from shoot clusters grew vigorously but the bulblets from shoot clusters grew very poor in 5L air-lift bioreactor culture. By the addition of 30 mL fresh liquid medium containing doulble strength MS salts, 250 g/L sucrose and 5 g/L activated charcoal after 8 weeks in the shoot cluster culture on MS medium with 5.0 mg/L BA and 0.5 mg/L IAA, the number of bulblets was increased in light condition, but the growth of bulblets was not affected by light. Bulblet production was possible with the bulblet product at 53 to 68 mg in fresh weight by liquid medium addition after the proliferation of shoot cluster.

• Electrical & Electronic Materials
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• v.1 no.4
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• pp.319-332
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• 1988

높은 포화자속밀도와 낮은 철손을 갖는 Fe/aub 80/B$_{12}$Si$_{8}$ 비정질합금을 일반열처리, 자장열처리시켜 그의 자기적특성과 자구구조와의 관계를 조사하였다. 이를 위하여 Fe$_{80}$B$_{12}$Si$_{8}$ 비정질리본을 단롤법으로 제작하여 결정화온도를 측정하였으며 측정된 결정화온도 이하의 여러 온도에서 30분간 Ar-gas 분위기하에서 일반열처리, 자장열처리를 행하였다. 이와같이 하여 준비된 시료의 자기적특성을 조사하기 위하여 D.C., A.C. Recorking Fluxmeter를 이용하였으며 자구구조는 Bitter method로 관찰하였다. as-cast 상태의 시료를 일반열처리함에 따라 내부응력이 완화되면서 maze자구가 점차 사라지고 wave형태의 180.deg.자구가 관찰되었다. 동시에 자화과정에 있어서 자기이력곡선은 Barkhausen jump가 없어 smooth하였다. 그리고 자장열처리시에는 as-cast 상태나 일반열처리에 비해 자기적특성이 현저하게 향상되었으며 이는 열처리를 행함에 따라 내부응력이 완화되면서 maze 자구가 없어지고 일축자기 이방성으로 리본길이방향에 평행하게 형성된 180.deg.자구에 기인하는 것이라 사료된다. 그리고 자장열처리의 경우, 폭방향으로 열처리한 리본의 자구폭은 길이방향으로 열처리한 리본의 폭보다 미세하였으며 전자의 이력손실이 후자의 것보다 더 컸다.다.

• Journal of the Korean Magnetics Society
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• v.27 no.1
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• pp.35-40
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• 2017

Kerr microscopy was assembled to observe magnetic domain image of ultra thin 3 %Si-Fe by using parts of an optical microscope. Digital images were obtained from CCD camera attached to the microscopy. A method was suggested to decide a boundary between magnetic domain regions in this study. The method was using some operations such as subtraction, integration and least mean square approximation for pixel values in the digital image. The method has a strong point that high priced image processor is not needed in the Kerr microscopy system. From the results that three different domain walls were observed and magnetic flux density of 0.085 [T], this method could be applied in the magnetic domain regions having a straight $180^{\circ}$ domain wall.

• Journal of the Korean Magnetics Society
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• v.5 no.3
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• pp.179-184
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• 1995

The ac magnetic susceptibility of {100} iron whiskers as a function of currents is studied with and without external field. The ac susceptibility depends on the magnitude and the direction of the applied dc current when a small external field is applied along the magnetization of the central domain of the whisker. Variation of the central domain size accounts for the current-dependent response. The measured magnetic responses are explained, using a micromagnetic calculation based on a simple model, as a function of applied currents over a wide range except critical values.

• Current Research on Agriculture and Life Sciences
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• v.29
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• pp.21-27
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• 2011

This study was carried out to produce multiple shoots and bulblets from flower stalk tissue cultures of Muscari armeniacum LEICHTLIN ex BAKER 'Early Giant', which were cultured in the half strength Murashige & Skoog's (MS) medium supplemented with auxin, NAA in combination with kinetin, BA, and TDZ, alone and/or. In flower stalk tissue culture, upper part explant was the most suitable as a source of culture material. Direct shoot formation was much more favorable in half strength MS medium supplemented with $0.1mg{\cdot}L^{-1}$ NAA and $1.0mg{\cdot}L^{-1}$ TDZ. On the other hand, bulblet formation was increased when cultured in half strength MS medium added with $0.01mg{\cdot}L^{-1}$ NAA and $0.1mg{\cdot}L^{-1}$, $0.2mg{\cdot}L^{-1}$ kinetin. Acclimatized plant flowered during the second year of the growing period without any phenotypic variations and formed average 1.5 bulblets per mother bulb.

• Korean Journal of Plant Tissue Culture
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• v.22 no.2
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• pp.83-87
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• 1995

Regulation of organ differentiation by growth regulators was investigated through the shoot-tip and bulb-scale cultures of Lilium longiflorum (cv Georgia). When shoot tips were placed on MS medium supplemented with 0.1 mg/L NAA alone or 0.1 mg/L NAA and 0.1 mg/L BA, axillary shoots were proliferated. Root diffentiation and growth were stimulated on the basal medium. Although growth regulation did not seem to be necessary when bulb scales were used as explants for shoot differentiation, its differentiation was promoted vigorously by 0.2 mg/L NAA, but suppressed by BA. Bulblets were formed from bulb-scale-derived plantlets cultured on MS medium supplemented with 0.1 mg/L IBA. And more bulblets were formed from the plantlet in MS medium supplying 0.2 mg/L NAA with 6% than3% sucrose

• Horticultural Science & Technology
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• v.16 no.3
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• pp.358-360
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• 1998

Series of in vitro experiments in Lilium callosum were conducted to investigate efficient multiplication through finding the optimal cultural environment, and organogenic capability of cultural explants, and then to determine the progressive method for enhancing bulblet growth in Lilium callosum scale culture. Twenty-four hr photoperiod was most effective for the growth of bulblet and the formation of other organs. Optimum light intensity for bulblet growth was 2,500~5,000 Lux. When bulbets were subcultured, growth of bulblets were enhanced by removing excessive leaf blade. Number of bulblets per scale increased as mother scale size increased, whereas diameter of bulblet from the small size mother scale increased. Bulblet formation and development was induced when explants were placed above the medium to be exposed to more light.

• Journal of the Korean Magnetics Society
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• v.14 no.6
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• pp.224-227
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• 2004

We have studied local magnetization reversal by laser annealing in exchange biased NiFe/FeMn bilayer. Local magnetization reversal was performed by using the DPSS laser under external magnetic field of 600G. When the laser illuminated the patterned film with the power of above 300 mW during 15 min, a magnetoresistance (MR) curve with symmetric peaks at the opposite field was obtained due to the local reversal of exchange biasing. The direction of exchange anisotropy in the locally reversed region can be restored by local laser annealing under alternating magnetic field, even if its MR peak was reduced by the damage and interdiffusion. The magnetic domain structure of the locally reversed region was measured by MFM. The new domains were generated by laser annealing near the exposed area.