• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.428-433
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• 1973

The quantitative separations of a mixture containing equal amount of each anion such as Si(IV), As(V), P(V), S(VI), W(VI) and Cr(VI) are carried out by the elution through 20${\times}3.14cm^2$ column of anion exchange resin, Dowex 1${\times}$8. The eluents are a mixture of 0.07 M hydrochloric acid and 0.03 M sodium chloride (pH = 1.30) for Si(IV), As(V) and P(V) species, a mixture of 0.6 M sodium chloride and 0.3 M sodium hydroxide for S(VI), W(VI) and Cr(VI) species, and 0.1 N sodium sulfite (pH = 3.48) for P(V) and As(V) species. The subsidiary anions in a standard mixture such as Si(IV), As(V), S(VI), P(V) and W(VI) are separated together from large amount of Fe(III) by the elution through 30cm${\times}3.14cm^2$ column of the resin, Dowex${\times}$50w${\times}$12, using a mixture of 0.1 M sodium nitrate and 2 percent dimethylsulfoxide aqueous solution as an eluent. Si(IV), As(V), S(VI), P(V) and W(VI) eluted together are separated quantitatively under the same conditions as in the separations of the anion mixture. By the conditions obtained in the separations of the standard mixture, Fe(III) and all of the subsidiary anions in steel are quantitatively separated.

• Resources Recycling
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• v.27 no.6
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• pp.53-58
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• 2018

Solvent extraction of Li(I) from weak HCl solution was investigated by the mixture of TBP/MIBK with other neutral extractants such as Cyanex 923, TOPO and TOP. The TBP/MIBK organic phase was loaded with 0.1 M $FeCl_3$ at different HCl concentrations (1-9 M). Extraction of Li(I) from weak HCl solution is related to the stability of $FeCl_3$ in the organic mixture. As HCl concentration increased in preparing the loaded TBP phase, the stripping percentage of Fe(III) during the extraction of Li(I) became reduced and thus Li(I) could be extracted by ion exchange reaction with hydrogen ion in the organic. The concentration of TBP in the extractant mixture affected the stability of $FeCl_3$. Compared to TBP, Fe(III) was easily stripped from the loaded MIBK and thus no Li(I) was extracted by the mixture with MIBK. The nature of neutral extractant with TBP/MIBK showed little difference in the extraction of Li(I) and stripping of Fe(III).

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.992-1000
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• 1997

Background : Since up to 90% of a theophylline dose is biotransformed, probably by interaction with one or more the variants of the cytochrome P-450 drug metabolism system, anti-tuberculosis agents including drugs influencing microsomal enzyme systems, such as isoniazid and rifampicin. may be affect the elimination of theophylline. Method : The effect of combination therapy with isoniazid(INH), rifampicin(RFP), ethambutol(EMB) and pyrazinamide(PZA) on the pharmacokinetics of theophylline was evaluated by a computer program using Bayesian method. Three group were divided as follows. Group I is control, Group II is treated with INH. RFP, EMB and PZA and Group III is treated with INH, RFP and EMB. All of them were ilon-smoker who were normal in liver and renal functions, and not administered drugs affecting on the clearance of theophylline with exception of anti-tuberculous agents. Results : When it compared control with test groups, the clearance of theophylline in Group II and Group III was significantly decreased(p<0.001), and half life in Group II and Group III showed significant elevation(p<0.001). However there were no significant differences in clearance and half life between the Group II and Group III. Conclusion : These results suggest that theophylline dose may be need of readjustment in concurrent medication of anti-tuberculous agents including INH, RFP, and EMB.

• Journal of the Korean Chemical Society
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• v.46 no.6
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• pp.509-514
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• 2002

A method to determin Fe(II) and Fe(III) ion in aqueous solution by chemiluminescence method using a stopped flow system has been studied. The method is based on the increased chemiluminescence intensity with the addition of Fe(III) ion to a solution of lucigenin and hydrogen peroxide. The effects of KOH concentration, flow rate of reagents, $H_2O_2$ concentration and citric acid concentration used for the masking of Fe(II) ion on the chemilu-minescence intensity have been investigated. The calibration curve for total Fe was linear over the range from 1.0${\times}$$10^{-6}$ M to 1.0${\times}$$10^{-4}$M, coefficient of correlation was 0.996 and the detection limit was 1.0${\times}$$10^{-7}$M under the optimal exper-imental conditions of 4.0 M, 2.0 M, 3.5 mL/min for the concentration of $H_2O_2,$ KOH and flow rate of reagents, respec-tively. The calibration curve for Fe(Ⅲ) was linear over the range from 1.0${\times}$$10^{-6}$M to 1.0${\times}10^{-4}$ M, the coefficient of correlation was 0.997 and the detection limit was 5.0${\times}$$10^{-7}$M under the optimal experimental conditions.

• Elastomers and Composites
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• v.49 no.1
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• pp.59-65
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• 2014

In this study, in order to complete curing reaction of the molding compound comprising an epoxy/anhydride at $71^{\circ}C$ for 40 hours, metal coordination complexes such as cobalt (II) acetylacetonate, potassium acetylacetonate, iron (III) acetylacetonate and chromium (III) octoate as a catalyst were applied to the epoxy/anhydride compounds respectively. The weight ratio of an epoxy part/an anhydride part was adjusted to improve the mechanical properties of the molding compound. According to the experimental results, an epoxy/anhydride compound containing chromium (III) octoate showed a high conversion at $71^{\circ}C$ for 40 hours as well as a proper processability at room temperature among the several metal coordination complexes. For the mechanical properties of the cured epoxy/anhydride compound, the compounds containing weight ratio from 0.9/1 to 0.5/1 of the epoxy part/anhydride part with chromium (III) octoate showed the high flexural strength, and higher compressive strength was shown with increasing of the hardener part.

• Journal of Life Science
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• v.18 no.1
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• pp.75-83
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• 2008

This studies were designed to elucidate whether inhibitors of topoisomerase regulate function and activity of topoisomerase, and gene expression in HL-60 human leukemia cells. HL-60 cells were treated with 10-hydroxycamptothecin or doxorubicin, total RNA was isolated, and expressed genes were investigated with human oligonucleotide microarray containing 10K gene, respectively. Expression profiles of the human leukemia HL-60 cells treated with 10-hydroxycamptothecin (10-CIT) or doxorubicin associated with signal transduction,. cell adhesion, cell cycle, cell growth, cell proliferation, cell differentiation, transcription and immune response, especially genes related with transcription and cell growth. In HL-60 cells treated with 10-CPT, the expression of topoisomerase III${\alpha}$, III${\beta}$ and I gene from oligo chip microarray analysis were increased over, but the expression of topoisomerase II${\alpha}$ and II${\beta}$ gene were decreased over. In contrast, the expression of topoisomerase II${\alpha}$ and II${\beta}$ gene were increased over in HL-60 cells treated with doxorubicin, whereas the expression of topoisomerase III${\alpha}$ and III${\beta}$ mRNA remained no significant change. These results suggest that these data may be useful for novel therapeutic markers.

• Journal of the Korean Chemical Society
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• v.43 no.5
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• pp.522-526
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• 1999

2-Hydroxybenzaldehyde-5-nitro-pyridylhydrazone (2HB-5NPH) was synthesized and its application to the spectrophotometric determination of iron was studied. The reagent reacts with iron in the pH range 6.0-7.5 to form a yellow coIored 1:2 chelate which is very stable in methanol solution. Beer's law is obeyed in the concentration range 0.05∼2.0 ${\mu}gmL^{-1}$ iron and separation procedure using a short column filled with Amberlite XAD-7 nonionic chelating resin is proposed for the spectrophotometric determination of traces of iron. The influence of several ions as interference was discussed. The separation of Fe(III) ion from the mix-ture solution were carried out with the buffer solution (pH 5.0) and 0.25M HCl as eluents.

• Resources Recycling
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• v.23 no.6
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• pp.22-29
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• 2014

Recycling process of iron should be developed for efficient recovery of neodymium (Nd), rare metal, from acid-leaching solution of Nd magnet. In this study, $FeCl_3$ solution as iron source was used for preparation of iron nano particles with the condition of various factors, such as, reductant, and surfactant. $Na_4P_2O_7$ and Polyvinylpyrrolidone (PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride ($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed by using XRD, SEM for measuring shape and size. Iron nano particles were prepared at the ratio of 1:5 (Fe (III) : $NaBH_4$). Size and shape of iron particles were round-form and 50 ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4P_2O_7$ was negative value, which was good for dispersion of metal particle. When $Na_4P_2O_7$ (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 nano particles which were round-shape, well-dispersed and near 100 nm-sized range. In this condition, $FeCl_3$ solution changed with spent Nd leachate solution, and then it is possible to be made round-formed iron nano particles at pH 9 and at the reaction bath over 20 L which is not include any surfactant.

• 월간산업보건
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• s.71
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• pp.15-21
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• 1994

발암물질에 대한 폭로를 완전히 제거한다는 것은 불가능하기 때문에, 어느정도로 폭로되는 것이 안전한 가를 규정하는 것은 매우 중요한 일이다. 작업성 암의 발생위험도를 정량적으로 평가한다는 것은 그 한 부분을 차지한다. 이에 대한 많은 시도가 행하여져 왔으나 실제로 이러한 정량적인 평가는 많은 가정(assumption)들을 근거로 하고 있다. 이 글은 Scandinacian Journal of Kork and Environmental Health 1992년 18호 Supplement 1 : 90-6호에 실린 내용을 중심으로 어떠한 가정들이 사용되고 있으며 이러한 평가가 어느 수준에 와있는지를 살펴보고자 하였다.

• Journal of Chest Surgery
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• v.11 no.4
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• pp.451-455
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• 1978

Rhabdomyosarcoma is relatively rare in general pediatric population. Furthermore, the primary site in the thorax is one of the least sites. Because most patient, when first seen, are extensively advanced and bad in prognosis, an adequate work-up prior to any definitive therapy must be undertaken. Author experienced 2 cases of embryonal rhabdomyosarcoma originating from chest wall. Both 2 cases are included in Group III [Rhabdomyosarcoma-Intergroup Protocol Grouping], one case is treated with radical surgery and radiation therapy, and the other case is treated with radiation therapy and chemotherapy. So author present 2 cases of embryonal rhabdomyosarcoma with reference.