• Journal of the Korean Chemical Society
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• v.18 no.4
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• pp.244-250
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• 1974

The mechanisms of the electrode reaction of chlorate ion were investigated, using Pt-electrode, by means of the technique of galvanostatic double pulses. For double current pulses (a cathodic pulse followed by an anodic pulse), the mechanism of the electrode reaction of chlorate ion over a current density range from 20 ma/cm2 to 25 ma/cm2 was suggested as the following: $CIO_3^-\;{\longrightarrow^{I}_{n_{1c}}\;CIO_2^-\;{\longrightarrow^{II}_{n_{2a}}\;CIO^-\;{\longrightarrow^{I'}_{n_{1a}}\;CIO_2^-\;{\longrightarrow^{II'}_{n_{2a}}\;CIO_4^-$ For a higher current density from 40 ma/cm2, it was suggested as the following: $CIO_3^-\;{\longrightarrow^{III}_{n_c}}\;CIO^-\;{\longrightarrow^{I'}_{n_{1a}}\;CIO_2^-\;{\longrightarrow^{II'}_{n_{2a}}\;CIO_4^-$ or $CIO_3^-\;{\longrightarrow_{n_c}}\;CIO^-\;{\longrightarrow_{n_a}}\;CIO_4^-$

• Journal of the Korean institute of surface engineering
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• v.30 no.4
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• pp.239-247
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• 1997

The electrochemical machining of carbon steel was carried in various electrolytes which contain NACl and $NaCIO_3$. Though electrolyte containg NaCl yields fast machining rate, dimensional control is rather difficult. In the case of electrolyte with $NaCIO_3$, dimensional control of anode shape can be obtained through modification of cathode design. Mathematical modeling is also performed for these systems and agreements are good compared with experimental date. The constant gap experiment butween two electrode yielded faster machining rate than constant cathode moving rate experiment.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.269-278
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• 2006

This study was performed to extend the shelf-life of duck breast treated with NaCIO(20, 50ppm), lactic acid(1, 2%) and acetic acid(1, 2%). Changes in microbial counts, storage characteristics and color values of duck breasts were determined during storage at 4℃ for 7 days. Although pH values were not different on the first day of storage. they increased up to 3rd days of storage and decreased gradually thereafter. Thiobarbituric acid reactive substances(TBARS) of duck breasts treated with lactic acid and acetic acids were lower TBARS than those with lactic acid on the 7th days of storage. Volatile basic nitrogen(VBN) didn't differ among the treatments(P>0.05). Although the microbial counts were increased in all treatments, acetic acid treatment had lower microbial counts among the treatments during storage. These results indicated that acetic acid would be the best treatment to extend the shelf-life of duck breasts among others.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.1
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• pp.52-61
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• 1997

This study was aimed to decrease AOX(Adsorbed Organic Halide Compounds) by applying bleaching methods of A(HNO$_3$ ＋ NaNO$_2$) and $D^{(H/L)}$(dual pH chlorine dioxide bleaching) to conventional OCEDED bleaching stages. And so we investigate the effects of NSA treatment and the influence of production rate of ion species in chlorine dioxide and pulp mixtures according to various pH as well as dual pH on pulp bleaching. Finally the effects of AOC_DED^{(H/L)}ED^{(H/L)}$ bleaching stage were investigated by measuring AOX, brightness, kappa number and viscosity of pulps. A stage was treated by using 4% $HNO_3$ and 0.05~2.0% $NaNO_2$ on pulp and $D^{(H/L)}$ stage was like that pulp mixed with chlorine dioxide solution was adjusted at pH 7.0 and reacted in pulp cosistency 3%, S~20min, $70^{\circ}C$, and then successively for 160~175min at pH 4.0. It was found that suitable $NaNO_2$ addition rate was at 0.6% where the brigtness of pulp was most higher and pulp viscosity was not decreased much. Chlorate ($CIO_3$) was decreased according to pH increase but chlorite($CIO_2$) was highly decreased according to pH increase. And chloride was slightly increased with pH increase. The applying of A and D^{(H/L)}$ bleaching stages to some various multiple bleaching stages ($AOC_DED^{(H/L)}/EopD^{(H/L)} etc.$) had good results that brightness was increased more 2~3% ISO than conventional method(OCEDEopD), but viscosity was dropped by only 1~2cps.

• Korean Journal of Plant Resources
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• v.16 no.2
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• pp.141-146
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• 2003

To improve the percentage of field germination of Zanthoxytum piperitum DC., storage in ground(control) and several chemicals as treatments was investigated. Germination percentage was 30.3 and 22.7% in GA$_3$(100 ppm) and NaCIO(10%), respectively compared with 17.3％ in storage in ground without treatments. Germination percentage reached maximum between 26 and 33 days after seeding and then increased slowly. Top/Root ratio was the highest at storage in ground after the treatment of GA$_3$ 100ppm.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.841-846
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• 1995

대전지역 토양에서 추출한 흄산(TJHA)과 Am(III), Eu(III)의 착물형성에 대한 안정도상수를 추출용매 di-2-ethylhexyl phosphoric acid와 희석제 toluene을 사용하여 용매추출법으로 구하였다. 이온강도가 0.1M NaCIO$_4$에서 TJHA의 총 carboxylate capacity를 직접 전위차적정법으로 분석한 결과 3.757 meq/g이고, apparent pKa는 5.15 이었다. TJHA와 Am(III) 및 Eu(III)의 조건부 안정도상수의 log$\beta$1 값과 log$\beta$2 값을 흄산의 이온화도 함수로 구한 결과, Eu-TJHA은 0.1M NaClO$_4$일때 log $\beta$1=5.948$\alpha$ + (6.83 $\pm$ 0.3) 및 log $\beta$2 = 5.687$\alpha$ + (10.44 $\pm$ 0.4)이며, Am-TJHA은 log$\beta$$_1$= 4.004 $\alpha$ + (6.96 $\pm$ 0.2) 및 log$\beta$$_2$= 3.719 $\alpha$ + (11.71 $\pm$ 0.2)이었다.

• Journal of the Korean Chemical Society
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• v.17 no.3
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• pp.145-153
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• 1973

The temperature effects on the equilibria between polymolybdatd anions in 1M sodium perchlorate solution has been investigated in the temperature range of 20~50$^{\circ}$C. The polymolybdate anions formed are heptamolybdate ($Mo_7O_{24}^{6-}$) ions and the protonized forms of heptamolybdate ions ($H_LMo_7O_{24}^{(6-L)-}$). The equilibrium constants for the formation of heptamolybdate ions calculated by Sillen's method are as follow;$8H^{+}+7MoO_4^{2-}=Mo_7O_{24}^{6-}+4H_2O$, $k_{7.8}=2.77{\times}10^{53}:20^{\circ}C= 9.29{\times}10^{51}:40^{\circ}C$,$k_{7.8}= 4.22{\times}10^{52}:30^{\circ}C = 9.29{\times}10^{51}:50^{\circ}C$ The enthalpy change for calculated for the above reaction is 31.51 kcal/mole. A method of calculation of the equilibrium constants for the formation of protonized heptamolybdate ions from heptamolybdate ions and hydrogen ions has been derived. The equilibrium constants calculated for the formation of protonized heptamolybdate ions are as follow; $ LH^++ Mo_7O_{24}^{-6} = H_LMo_7O_{24}^{(6-L)-} : L = 1\;or\;2$, $k_1 = 2.31{\times}10^4=2.53{\times}10^4=2.76{\times}10^4= 3.10{\times}10^4$, $k_2 = 6.19{\times}10^7\;20^{\circ}C = 7.80{\times}10^7\;30^{\circ}C = 1.22{\times}10^8\;40^{\circ}C = 2.03{\times}10^8\;50^{\circ}C$The enthalpy change for the following step reactions are as follow;$H^{+}+Mo_7O_{24}^{6-}= HMo_7O_{24}^{5-}\;{\Delta}H^{\circ}=1.90 kcal/mole$, $2H^{+}+Mo_7O_{24}^{6-}=H_2Mo_7O_{24}^{4-}\;{\Delta}H^{\circ}=7.50kcal/mole$

• Journal of Korean Society of Water and Wastewater
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• v.18 no.5
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• pp.588-597
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• 2004

In this research, we investigated the variation of transmembrane pressure and permeate water quality with pre coagulation and sedimentation with iron based coagulant and chlorination of feed water for PVDF (polyvinylidene fluoride) based MF membrane filtration. NaCIO was fed to the membrane module with dosage of 0.5mg/L and maintained during filtration. To observe the effect of raw water, three types of raw and processed waters, including river surface water, coagulated water and coagulated-settled water, were applied. In case of river surface water, the transmembrane pressure increased drastically in 500 hours of operation. On the contrary, no significant increase in transmembrane pressure was observed for 1,200 hours of operation for coagulated water and coagulated-settled waters. The turbidity of permeate was lower than a detection limit of equipment for all raw waters. The removal efficiency of humic substances of coagulated water and coagulated-settled water was approximate ten times of that of surface river water. And, the removal efficiency of TOC and DOC was approximate two times of that of surface river water. From the results of plant operation, stable operation was maintained at $0.9m^3/m^2{\cdot}day$ filtration flux through the combination of pre-coagulation and pre-chlorination. However, the water quality of permeate was the best when pre-coagulation-sedimentation process was combined with pre-chlorination.

• Information Systems Review
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• v.7 no.2
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• pp.195-211
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• 2005

The purpose of this case study is to suggest the indicators of an informatization maturity level and critical success factors in small and medium automotive parts manufacturers. To achieve this goal, literature reviews and case studies on 7 automotive parts manufacturers that confirmed to implement information systems successfully, were conducted. Based on literature review, the six functional processes including development, production scheduling, purchase, production, order, and support process, were defined. Each process has 5 levels from 1(low level) to 5(high level) depending on the degree of informatization maturity. In addition, critical success factors were discovered with interviews of CEO or CIO. The results of this study can be applied to any companies which are implementing or intended to the information systems near future.

• Food Science and Preservation
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• v.11 no.3
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• pp.331-335
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• 2004

This study was carried out to improve quality of minimally processed lettuce with various treatments. The treatments for preventing enzymatic browning were using different chemical immersion solutions and controlling microbial growth were using chlorine, electrolyzed water, and organic acid. The solution with ascorbic acid 1$\%$ and citric acid 1 $\%$ showed a positive effect on antibrowning of minimally processed lettuce. In the inhibition of microorganisms growth, 200 ppm NaCIO solution was more effective than fermented pollen solution and Na-dichloroisocyanurate solution. In electrolyzed water system, no-diaphragm system showed inhibitory effect of microorganisms growth. Also, total microorganisms count of minimally processed lettuce with ascorbic acid and citric acid solution was lower by about 4 log cycle after 4 days storage at l0$^{\circ}C$.