• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.467-472
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• 2009

This study was conducted to break down the self-incompatibility of Astragalus membranaceus Bunge by old-flower pollination, NaCl and $CO_2$ treatment. The old-flower pollination in green house produced fertilization during the 1st and 2nd day after flowering from early September to early October, but almost no fertilization in late August. The most successful pollination occurred in late September at the 1st day after flowering when pod setting was 33.3% and that of seed set was about 86.2%. The old-flower pollination in field showed pod setting for the control group from late August to early October, but no seed set except the days of mid-September and late September. The most successful pollination occurred in late September during the 2nd day of flowering when the percentage of pod setting was 39% and that of seed set was 94.9%. The wrapping in field set pods from late August to early October, but did not set seeds except in mid and end of September. The percentage of pods was 39% and percentage of seeds was 94.9% about flowering after first day in end of September. by field culture. The best result from NaCl treatment was achieved when 1% NaCl treatment in green house produced 21.3% of pod setting in early October and 66.7% of seed set in late September. In field, NaCl 5% treatment produced best result with 7.3% of pod setting and 90.9% of seed set in mid-September. No differences were observed between the $CO_2$ 700ppm treatment and the control group.

• Textile Coloration and Finishing
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• v.4 no.3
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• pp.65-73
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• 1992

To control the hydrolysis rate of PET fabric with NaOH, HCl and $CH_3$COOH(HAc), as regulating reagent, were added to the 0.5 M NaOH solution. The concentrations of acids in 0.5 M NaOH were varied. PET fabrics were treated with aqueous solutions of acids in 0.5 M NaOH under different conditions. The weight loss of PET fabric, the rate of hydrolysis, the apparent activation energy (E$_{\alpha}$), the handle value, the etched surface of treated PET fabric, and the effect of salts such as NaCl, $CH_3$COONa(NaAc), and NH$_4$Cl on the weight loss were discussed. Acids in the aqueous 0.5 M NaOH solution decreased the weight loss of PET fabric bacause of neutralization of OH- and the weight loss of PET fabrics treated with corresponding concentration of aqueous NaOH solution to the concentrations of the aqueous solutions of acids in 0.5 M NaOH was lower than that of PET fabrics treated with aqueous solutions of acids in 0.5 M NaOH. The addition of NaCl to aqueous NaOH solution accelerated the reaction of OH- with PET greatly, the addition of NaAc increased the weight loss slightly, but the addition of NH$_4$Cl decreased the weight loss. It was thought that the very remarkable result that NaCl in aqueous NaOH solution promoted the hydrolysis of PET with NaOH would contribute to the conservation of energy and NaOH in the weight loss finishing process of PET fabric. The etched surface and the handle value of treated PET fabric were independent of the difference in the kinds of acids and salts added.nd salts added.

• Korean Journal of Microbiology
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• v.26 no.4
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• pp.339-347
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• 1988

The rate of bacterial degradation of hydrocarbon was estimated for the measurment of the self-purification capacity of the aquatic ecosystem. Strain ND601P-2, selected as petroleum degrading bacteria from Nakdong River Estuary with high degradability of petroleum, transformed 42% of hexadecane to $CO_{2}$ or cell mateials under the conditions of $25^{\circ}C$, 0.03M NaCl, 167mg-$NH_{4}^+/1, 950 mg-PO_{4}^{3-}$/1, 50 mg-hexadecane/1. The mineralization rate was found to be significantly affected by the temperature and the $Q_{10}$ value was 2.2. Teh optimal salinity of the strain ND601P-2 was 2o/oo. The increased salinity caused the elevation of % respiration value and the prolonged lag phase.

• Korean Journal of Optics and Photonics
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• v.6 no.1
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• pp.39-44
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• 1995

3차원 .delta.-potential을 가진 원자 모델을 이용하여 Nd:YAG(1064nm), Ti:sapphire(806nm), 색소(616nm), XeCl(308nm) 레이저를 기본파로 하고, 1차 이온화된 K/sup +/, Na/sup +/, Li/sup +/ 등의 알칼리 금속 이온을 비선형 매질로 할 때 고차고조파 분포를 수치적으로 해석하였다. 계산 결과 고차고조파 발생에서 특징적으로 나타나는 plateau는 비선형 매질의 이온화 에너지가 클수록, 기본파의 파장이 길수록 높은 차수에서 폭넓게 나타나고, 그 강도는 감소한다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2010.10a
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• pp.219-220
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• 2010

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6187-6195
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• 2012

Recycling process of iron should be developed for efficient recovery of neodymium(Nd), rare metal, from acid-leaching solution of neodymium magnet. In this study, $FeCl_3$ solution as iron source was used for synthesis of iron nanoparticle with the condition of various factors, etc, reductant, surfactant. $Na_4O_7P_2$ and polyvinylpyrrolidone(PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed with instruments of XRD, SEM and PSA for measuring shape and size. Iron nanoparticles were made at the ratio of 1 : 5(Fe (III) : $NaBH_4$) after 30 min of reduction time. Size and shape of iron particles synthesized were round-form and 50 nm ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4O_7P_2$ was negative value, which is good for dispersion of metal particle. When $Na_4O_7P_2$(100 mg/L), PVP($FeCl_3$ : PVP = 1 : 4, w/w) and Pd($FeCl_3$ : $PdCl_2$ = 1 : 0.001, w/w) were used, iron nanoparticles which are round-shape, well-dispersed, near 100 nm-sized can be made.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.229-232
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• 2005

The study on the improvement of manufacturing process of RJ-4 liquid fuel that have high flash point, was carried out. In preparing of RJ-4 using commercially available MCPD, 1st, 2nd hydrogenation and isomerization reaction were enabled 1 step continuous process by combined use of heteropoly phosphoroustungstic cesium salt catalyst and 2nd stage-heat-controllable reactor. Also when heteropolyacid cesium salt was used as a isomerization catalyst instead of aluminum chloride, formation rate of exe-THDMCPD was higher, the catalyst could be easily separable from product and there was no production of waste acid, so this new reaction condition was confirmed as the environment friendly process.

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.574-578
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• 1993

Laser-induced photoacoustic spectroscopy (LIPAS), which utilizes the photothermal effect that results from nonradiative relaxation of excited state molecules, was used in the speciation analysis of the complexes of neodymium(III) and water soluble synthetic polyelectrolyte, poly methacrylic acid (PMAA), in 0.1 M $NaClO_4$ at pH of 6.0. The minimum detection limit of Nd(III) by LIPAS was $5.O{\times}10^{-6}$ M. Experiment was carried out at low concentration ratio of Nd(III) to PMAA to assure that 1 : 1 complexes predominate. The bound and free Nd(III) species were characterized by measuring nonradiative relaxation energy of the excited states $(^2GM{7/2}\;and\;^4G_{5/2})$ to the metastable state $(^4G_{3/2})$. Two species were quantified by deconvolution of the mixed spectrum using their respective reference spectra. The conditional stability constant measured by LIPAS was 5.52 L$mol^{-1}$.

• Journal of Electrochemical Science and Technology
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• v.12 no.4
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• pp.398-405
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• 2021

To fabricate a full-scale pilot model of the cost-effective Na-(Ni,Fe)Cl₂ cell, a Na-beta-alumina solid electrolyte (BASE) was developed by applying a one-step synthesis cum sintering process as an alternative to the conventional solid-state reaction process. Also, Fe metal powder, which is cheaper than Ni, was mixed with Ni metal powder, and was used for cathode material to reduce the cost of raw material. As a result, we then developed a prototype Na-(Ni,Fe)Cl₂ cell. Consequently, the Ni content in the Na-(Ni,Fe)Cl₂ cell is decreased to approximately (20 to 50) wt.%. The #1 prototype cell (dimensions: 34 mm × 34 mm × 235 mm) showed a cell capacity of 15.9 Ah, and 160.3 mAh g^-1 (per the Ni-Fe composite), while the #2 prototype cell (dimensions: 50 mm × 50 mm × 335 mm) showed a cell capacity of 49.4 Ah, and 153.2 mAh g^-1 at the 2^nd cycle.

• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.374-378
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• 1991

The electrochemical reduction behavior of Bilirubin (BR) in phosphate buffer (pH 7.8) solution was studied by DC polarography, differential pulse polarography, cyclic voltammetry and controlled potential coulometry. In DC polarogram, two reduction waves of BR were found. The half wave potentials of two reduction waves were -1.32 and -1.51 volts vs. Ag/AaCl respectively. The current type of 1st reduction wave was diffusion-controlled and the 2$^{nd}$ reduction wave was diffusion current containing a little kinetic current. The electrochemical reduction process of BR at each reduction step was all irreversible. The prewave appeared at lower concentration than 3.4 ${\times}$ 10$^{-4}$M, this prewave was identified as adsorption prewave. And the number of electron transfered in reduction steps, n$_{app}$ was two for the 1st reduction step and one for the 2$^{nd}$ reduction step.