• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.137-142
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• 1999

This study was carried out to investigate the effects of bulb size, type of media, depth of planting, and nutrient compositions on sprouting and growth of tissue cultured garlic microbulbs in hydroponic culture. Early and increased sprouting were observed when the microbulbs were transplanted into soil planted in shallow (1 cm in depth), while bulb size and fresh weight of the whole plant increased in deep planting (3 cm in depth). Bulb size have greatly influenced on not only sprouting rate but also plant growth after planting. Large bulbs resulted in high growth rate such as number of leaves, stem width, plant height, and increase in bulb size after planting. It was shown that Oriental nutrient solution (N=0.17, P=0.45, K=1.29, Ca=2.44, and Mg=0.98 me/L) was more effective in sprouting and further growth of microbulbs as compared to Yamazaki solution (N=0.27, P=0.16, K=1.50, Ca=1.36 and Mg=0.78 me/L). Microbulbs grown in mixture of leaf mould + bark + sand or Baroko showed the most vigrous growth.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.417-423
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• 2010

In this study, an effective method to prepare granular binderless ZSM-5 which is as efficient p-xylene separatory adsorbent was explored. Colloidal silica sol 30 wt% solution as an inorganic binder and microcrystalline cellulose as an organic additive were added to ZSM-5 powder ($SiO_2/Al_2O_3$ = 50). Adsorbent with enough strength (0.721 kgf), high crystallinity (94.6%) and high BET specific surface area ($379.2m^2$/g) was obtained by calcination, binderless treatment, ${NH_4}^+$ ion exchange, and activation after spherical granulation process. A batch type adsorption experiment was proceeded with solutions comprising 3 xylene isomers by 1 : 1 : 1 weight ratio to evaluate adsorption characteristics of prepared absorbent. As a result, the obtained binderless ZSM-5 granule showed a higher selective adsorption performance for para-xylene than that of commercial adsorbent.

• Applied Chemistry for Engineering
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• v.2 no.4
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• pp.372-384
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• 1991

The sulfation of the domestic titaniferous magnetite ore with ammonium sulfate was investigated to find a cyclic process for the production of synthetic rutile and high purity iron oxide and to test the feasibility of ammonium sulfate being an alternative sulfation agent. The proper sulfation conditions were determined to be a temperature of $425^{\circ}C$, 2.5 hours of reaction time, the weight ratio of ammonium sulfate to titaniferous magnetite : 11, and particle size or titaniferous magnetite : -250 mesh. 90.4 % of $TiO_2$ and 85.3 % of iron were extracted from the titaniferous magnetite sulfated under these conditions by the water leaching. From the leachate $TiO_2$ of 93.8 % purity as a mixture of rutile and anatase and ${\alpha}-Fe_2O_3$ of 97.6 % purity were obtained.

• Fire Science and Engineering
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• v.13 no.4
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• pp.7-12
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• 1999

Thermal properties of EVA dust and its risks of coexisting with oxidizer were investigated by a pressure vessel. The decomposition of EVA dust with temperature using DSC and the weight loss with temperature using TGA were also investigated to find the thermal hazard of EVA dust. Using the pressure vessel which can estimate ignition and explosion of EVA dust coexisting with oxidizer by bursting of a rupture disc, many experiments have been conducted by varying the orifice diameter, heating rate, the weight ratio of the sample coexisting with oxidizer, and the species of oxidizer. According to the results of the thermal analysis of EVA dust, a little change of the decomposition initiation temperature with the heating rate could be found and the decomposition temperature zone of EVA dust was 250 to 50$0^{\circ}C$. The risk of EVA dust coexisting with oxidizer was increased as the orifice diameter was decreased. On the other hand, it was increased as the heating rate and the weight ratio of the sample coexisting with oxidizer were increased. In addition, the risk of EVA dust coexisting with oxidizer was affected by the decomposition temperature of the sample and oxidizer, respectively, at slow heating rate, but it was affected by the oxygen weight percent of oxidizer at fast heating rate.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.10
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• pp.1069-1074
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• 2014

In this study, the piezoelectric characteristics of a piezoelectric paint sensor were investigated in relation to the poling time. This piezoelectric paint sensor was composed of PNN-PZT powder and epoxy resin with a 1:1 weight ratio. The dimensions of the paint specimen were $40{\times}10{\times}1mm^3$, and the top and bottom sides were both coated with a silver paste to create electrodes. During the poling treatment, the poling time was controlled to examine the effect of the piezoelectric properties, while the poling temperature was fixed at room temperature and the electric field was set to 4 kV/mm. The piezoelectric properties were measured by comparing the output voltage from the paint sensor to the force signal from an impact hammer when the impact hammer hit the specimen. In conclusion, the optimal poling conditions were found to be an electric field of 4 kV/mm and a poling time of around 30 min at room temperature.

• Biomedical Science Letters
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• v.5 no.1
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• pp.51-58
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• 1999

To evaluate an effect of liver damage on the dermal oxygen free radical metabolizing enzyme activities, the $CCl_4$ (0.1 ml/ 100 g body wt., 50% $CCl_4$ in olive oil) was intraperitoneally given to the rats every other day for 2 weeks. Based on the histopathological findings, liver weight (%), serum alanine aminotransferase, xanthine oxidase activities and hepatic lipid peroxide contents, the animals were induced severe liver damage. In the present liver damaged animal, all the activities of dermal scavenging enzymes such as superoxide dismutase, catalase and glutathione peroxidase were significantly decreased compared with central. And under the cytochemical electron microscopy the more coarse granules of cerrous perhydroxide were found compared with the control. In conclusion, the $CCl_4$-induced liver damage may influence upon the activities of some dermal oxygen free radical scavenging enzymes.

• Research in Plant Disease
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• v.22 no.4
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• pp.284-288
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• 2016

A plant growth promoting rhizobacterium, Bacillus vallismortis BS07M, was formulated as a clay pellet (CP) to evaluate its pepper growth promotion and induced resistance against various diseases under field and storage conditions. Peppers were grown in 50-hole tray containing potting mixture with CP in seedling raising stage, and then it was transplanted into a field. After transplanting, pepper plants treated with CP in seedling raising stage increased shoot growth and reduced disease severity caused by Phytophthora capsici in detached pepper leaves compared to untreated control. Moreover, treatment with CP in seedling raising stage increased fruit weight per plant; after harvesting, pepper fruits shown reduced diameter of lesions by Colletotrichum acutatum, and occurrance of soft rot in storage condition. These results indicated that CP could affect plant growth and induced resistance in pepper plants under field condition, and maintenance of fruit during storage.

• Journal of Navigation and Port Research
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• v.35 no.8
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• pp.613-618
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• 2011

Vessels on anchoring are sometimes dragged due to the increased external forces. For preventing the dragging, it is required to enhance the holding power of the anchor. The holding power depends on the type and weight of the anchor and the seabed condition. Especially, the holding power of AC-14 type anchor is known to be 2~2.5 times bigger than that of ASS type anchor. However, these coefficients was determined nearly by the result of the model test, so there is a need to verify that by sea trial. Therefore actual dragging case was analyzed and then compared with the coefficients in use, it was found that the two of them are much alike.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.202.1-202.1
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• 2014

최근 대용량 에너지 저장장치로 사용하고자 하는 리튬-공기전지는 리튬 음극과 액체 전해질 사이의 화학적 불안정성이 문제가 되고 있다. 또한 리튬이온전지는 액체전해질의 사용으로 인해 폭발 등의 안정성 문제가 대두되고 있는 실정이다. 때문에 리튬-공기전지에서 리튬 음극을 액체 전해질로부터 보호할 수 있으며, 리튬이온전지의 액체전해질과 대체하였을 때 전극과도 안정한 고체전해질의 연구가 필요하다. 고체전해질은 구조적으로 crystalline, glassy, 폴리머로 나눌 수 있는데, 이 중 crystalline 구조의 고체전해질은 glassy 및 폴리머 고체전해질에 비해 상온에서 비교적 이온전도도가 높다고 알려져 있다 [1]. 그러나 이온전도도가 높은 황화물 및 질화물 고체전해질은 수분에 민감한 반면 [2,3], 산화물 계열의 물질은 안정할 것으로 예상된다. 본 연구에서는 이온전도도가 높은 산화물인 lithium lanthanum titanate ($Li_{0.5}La_{0.5}TiO_3$, LLTO)를 고체전해질로 선정하여 다양한 환경에서 화학적 안정성에 관해 연구하였다. LLTO와 각종 용액과의 화학적 안정성을 살펴보기 위해 고체전해질을 DI water, 1 M $LiPF_6$ Ethylene Carbonate (EC)-Dimethyl Carbonate (DMC) (50:50 vol.%), 0.57 M LiOH (pH=13), 0.1 M HCl (pH=1)에 immersion하고 무게, 표면형상, 상(phase), 이온전도도 등의 변화를 관찰하였다. 또한 LLTO와 전극간의 반응성을 알아보기 위해 LLTO 분말과 음극물질인 $Li_4Ti_5O_{12}$ 및 양극물질인 $LiCoO_2$ 분말을 혼합한 후 $300^{\circ}C{\sim}700^{\circ}C$의 온도범위에서 열처리하여 반응을 가속화 한 후 상변화 현상을 살펴보았다.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.348-352
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• 1983

The atomization of barley tea concentrate with paint spray gun of two fluid nozzle was investigated. The physical properties of barley tea concentrate were correlated to the operating parameters; soluble solid concentration, viscosity, specific gravity and surface tension. The air to liquid feed ratios at various barley tea concentration were correlated to the air pressures applied. The diameters of sprays at various air pressures (from 164 mmHg to 564 mmHg) and soluble solid concentrations (from 3.1% to 25.2%) were also investigated.