• Title/Summary/Keyword: hydrogen extraction

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The Comparative Study on Decoctions of Yukmijihwang-tang (Liuweidihuang-tang) Extracted by Different Extraction Method and Extraction Time (전탕 방법 및 전탕 시간에 따른 육미지황탕 전탕액 비교 연구)

  • Kim, Jung-Hoon;Seo, Chang-Seob;Jeon, Woo-Young;Shin, Hyeun-Kyoo
    • Herbal Formula Science
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    • v.19 no.1
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    • pp.175-182
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    • 2011
  • Objectives : This study was performed to compare the differences between decoctions extracted by different extraction method and extraction time. Methods : Decoctions were prepared with pressed or non-pressed extraction conditions for 60, 120 and 180min. The yields of extracts, sugar contents, hydrogen ion concentrations(pH), the contents of reference compounds in Yukmijihwang-tang(Liuweidihuang-tang) were investigated. Results : The yields and the dissolved solid content containing sugar content of decoctions were more in pressed extraction method than unpressed extraction method, and they tended to be increased as extraction time increased. The pH values of decoctions methods did not show significant differences between pressed and unpressed extraction methods or extraction times. Most of reference compounds showed higher contents in pressed extraction method than unpressed extraction method and their contents were augmented according to increase of extraction time. The content of paeonol was decreased when extracted in more than 120min with pressed extraction method and tended to be decreased as extraction time increased in unpressed extraction method. Conclusions : The pressed extraction with long extraction time could be useful for decoction of Yukmijihwang-tang(Liuweidihuang-tang). However, another ingredients possible to decrease in such condition need to be considered to determine suitable extraction condition.

Manufacture of Permalloy Soft Magnets by Powder Injection Molding

  • W.Y. Jeung;Park, J.W.
    • Journal of Magnetics
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    • v.6 no.1
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    • pp.13-18
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    • 2001
  • Permalloy soft magnets have been produced by the powder injection molding process. Rheological characteristics of mixtures, debinding conditions, and the magnetic properties of permalloy after sintering have been investigated. A permalloy soft magnet with a permeability of 14200 could be obtained by preparing a mixture with a powder loading of 65.4 vol % and a PP/PEG binder systems solvent extraction, thermal debinding, and subsequent sintering at 1350$\^{C}$ in hydrogen. The permalloy soft magnet sintered in hydrogen had 95% of theoretical density and a magnetic induction of 13.2 kG in an applied magnetic field of 50 Oe.

Manufacturing of the Permalloy Soft Magnet by Powder Injection Molding Process

  • W. Y. Jeung;Park, J. W.
    • Proceedings of the Korean Magnestics Society Conference
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    • 2000.09a
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    • pp.217-227
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    • 2000
  • The permalloy soft magnet was produced by powder injection molding process. Rheological characteristics of mixtures, debinding conditions and the magnetic properties of permalloy after sintering ware investigated. The permalloy soft magnet with a permeability of 14200 could be obtained by preparing a mixture with a powder loading of 65.4 vol.% and PP/PEG binder system, solvent extraction, thermal debinding and subsequent sintering at 1350 $^{\circ}C$ in hydrogen. The permalloy soft magnet sintered in hydrogen showed a 95 % of theoretical density and a magnetic induction of 13.2 kG at the applied magnetic field of 50 Oe

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The influences of extraction time and pressure on the chemical characteristics of Gyejibokryeong-hwan decoctions

  • Kim, Jung-Hoon;Lee, Nari;Shin, Hyeun-Kyoo;Seo, Chang-Seob
    • The Korea Journal of Herbology
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    • v.29 no.6
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    • pp.1-6
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    • 2014
  • Objectives : This study was aimed to compare Gyejibokryeong-hwan (GBH) decoctions produced using different pressure levels for various extraction times to find the optimal extraction conditions through extraction yield, total soluble solids content (TSSC), hydrogen ion concentration (pH), and the contents of chemical compounds. Methods : Decoctions of GBH were prepared under the pressure levels of 0 or $1kgf/cm^2$ for 30-180 min using water as extraction solvent. The extraction yield, TSSC, and pH were measured, and the amounts of the chemical compounds were determined using high performance liquid chromatography-photodiode array detector. Results : The higher pressure and longer extraction time increased the values of TSSC and extraction yield, while decreased the pH value. The decoctions produced in 180 min by pressurized method and produced in 150 min by non-pressurized method showed maximum values of extraction yield and TSSC with minimum value of pH. The amounts of chemical compounds showed variations in pressurized and non-pressurized decoction during overall extraction times. The influences of pressure and extraction time on extraction yield, TSSC, pH, and the contents of chemical compounds were confirmed by regression analysis, which showed that all extraction values were significantly affected by at least one of two extraction factors, pressure and extraction time. Conclusions : This study suggests that the pressure and extraction time can significantly affect the extraction efficiency of components from GBH decoctions. However, optimal extraction conditions could not be chosen due to the variation of the amounts of chemical compounds.

Equlibrium and Kinetics of Metal Extraction by Amidoxime (Amidoxime에 의한 금속 추출 평형 및 추출 속도)

  • Shin, Jeong-Ho;Min, Seong-Kee;Jeong, Kap-Seop;Kim, Joo-Seok
    • Applied Chemistry for Engineering
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    • v.5 no.1
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    • pp.149-159
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    • 1994
  • The kinetics and equilibrium of metal extraction by benzamidoxime and phenylacetamidoxime-chloroform were investigated to apply amidoxime to metal extraction as chelating agent. The overall extraction constant extraction mechanism and selective extraction of copper were examined from the relation among extraction ratio, hydrogen ion concentration and extractant concentration. The experimental rate equation of copper extraction coincided with the theoretical rate equation and was expressed as $R_o=k{\overline{C}}_{HRo}(C_{Mo}/C_{Ho})^{1/2}$. The chemical species extracted was found to the type of ${\overline{CuR_2}}$.

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Compositional Differences of Ojeok-san (Wuji-san) Decoctions Using Pressurized or Non-pressurized Methods for Variable Extraction Times

  • Kim, Jung-Hoon;Seo, Chang-Seob;Kim, Seong-Sil;Shin, Hyeun-Kyoo
    • Journal of Pharmacopuncture
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    • v.15 no.2
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    • pp.24-30
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    • 2012
  • This study compared Ojeok-san (Wuji-san in Chinese) decoctions produced using different extraction methods for variable times. Decoctions were extracted in pressurized or non-pressurized conditions for 60, 120, and 180 mins. We investigated the Ojeok-san extract yield, the total soluble solid content, the hydrogen ion concentration (pH), and the reference compound content. The extract yield and the total soluble solid content were higher in decoctions produced by non-pressurized extraction; both were proportional to the extraction time. The pH tended to decrease as the extraction time was increased in decoctions produced using both methods. After 60 and 180 mins, the levels of albiflorin, paeoniflorin, nodakenin, naringin, and neohesperidin were significantly higher in decoctions extracted using the non-pressurized method compared with those extracted using the pressurized method. After 120 mins, only cinnamaldehyde was extracted in a greater amount in pressurized decoctions compared with non-pressurized decoctions. The levels of paeoniflorin, ferulic acid, nodakenin, naringin, hesperidin, neohesperidin, and glycyrrhizin increased with time in non-pressurized decoctions. This study showed that the use of pressurized and non-pressurized extraction methods for different times affected the composition of Ojeoksan (Wuji-san) decoctions.

Pulp Bleaching Effect and Ionization Rate of Chlorine Dioxide by Additive and Various pH Conditions (II) (pH와 첨가제에 의한 이산화염소의 분해율 및 펄프 표백효과(2)-첨가제가 chlorate 생성량의 감소와 펄프 표백 효과에 미치는 영향)

  • 윤병호;왕립군
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.4
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    • pp.49-57
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    • 1999
  • In CLO2 delignification and bleaching process, formation of chlorate corresponds to a loss of 20-36% of the original CKO2 charge. Because chlorate is inactive and harmful to environmental, it will be of benefit to find methods that can reduce the formation of chlorate during chlorine dioxide bleaching. Chlorate is mainly formed by the reaction HCIO +ClO2 $\longrightarrow$H+ + Cl_ +ClO3-2 On the other hand, AOX in chlorine dioxide bleacing is formed also due to the in-situ produced hypochlorous acid. THus both AOX and chlorate could be reduced by addition of hypochlorous acid. Some paper son the reduction of AOX by additives appeared , but systematic data on chlorate reduction as well as pulp and effluent properties are not available. THus this paper of focused on the effects on the reduction of chlorate and chlorine dioxide bleachability. The additives, fulfamic a챵, AMSO, hydrogen peroxide, oxalic acid were found to eliminate chlorine selectively in chlorine and chlorine dioxide mixture.However, when they were added to bleaching process, sulfamic acid and DMSO showed significant reduction of chlorate formation but hydrogen peroxide and oxalic aicd did not, and significant amount ofhydrogen peroxide was found resided in the bleaching effluent , In addition, sulfamic acid and DMSO decreased the bleaching end ph values while hydrogen peroxide and oxalic acid did not, which also indicated that hydrogen peroxide and oxalic acid were ineffective. The difference might be ascribed to the competitives of hypochlorous acid with lignin, chlorite (CKO2) and additives. Sulfamic acid and DMSO showed better pulpbrightness development but less alkaline extraction efficiency than hydrogen peroxide , oxalic acid and control, which means that insitu hypochlorous acid contributes to the formation of new chromophore structures that can be easily eliminated by alkaline extraction. DMSO decreased the delignification ability of chlorine dioxide due to the elimination of hypochlorous acid, but sfulfamic acid did to because the chlroinated sulfamic acid had stable bleachability. In addition, sulfamic acid, and SMSO shwed decreased color and COD of bleaching effluents, hydrogen peroxide decreased effluent color but not COD content, and oxalic acid had no statistically significant effects. No significant decreases of pulp viocosity were found except for hydrogen peroxide. Based on our results , we suggest that the effectiveness of hydrogen peroxide on the reduction of AOX in literature might be explained by other mechanisms not due to the elimination of hypochlorous acid , but to the direct decomposition of AOX by hydrogen peroxide.

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Changes in Chemical Compositions of Green Tea (Camellia sinensis L) under the Different Extraction Conditions (침출 조건에 따른 녹차 추출물의 성분 조성 변화)

  • 최혜자;이우승;황선주;이인중;신동현;김학윤;김길웅
    • Journal of Life Science
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    • v.10 no.2
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    • pp.202-209
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    • 2000
  • The factors affecting chemical composition of green tea (Camellia sinensis L.) during extraction process were temperatures and times. The optimum extraction conditions were measured in relation to the changes of chemical compositions from water extracts of green tea (Camellia sinensis L.) under different extraction temperatures (50, 70, 9$0^{\circ}C$) and extraction times (1, 3, 5 minute). The change of color intensity during browning reaction, flavonoid components, contents of total phenols and hydrogen donating activity (reducing activity for $\alpha$, $\alpha$'-diphenyl-$\beta$ -picryhydrazyl) of water extracts form green tea increased as extraction temperatures increased from 50 to 9$0^{\circ}C$ and extraction times prolonged from 1 to 5 min. The contents of important free sugars such as sucrose and glucose slightly increased as the extraction time was prolonged, while little difference in the content of fructose with the prolonged extraction time. Catechins contents extracted from the commercial steamed green tea were increased at higher temperature and longer extraction time. Epigallocatechin (EGC) extracted from 9$0^{\circ}C$ (extraction time 5 min). presented 99.9 mg/g in highest composition of catechin followed by epigallocatechin gallate (EGCg), epicatechin (EC), epicatechin gallate (ECg). The content of vitamin C extracted from green tea was increased about 2 times as the extraction temperature increased from 50 to 9$0^{\circ}C$ and as the extraction time increased from 1 to 5 min. with exception at 9$0^{\circ}C$(extraction time:5 min) which showed less vitamin C content than 7$0^{\circ}C$(extraction time : 3 min) probably due to possible destruction of vitamin C by high temperature.

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The Compositional Differences of Sipjeondaebo-tang(Siquandabu-tang) Decoctions Extracted by Different Extraction Method and Extraction Time (전탕 방법 및 전탕 시간에 따른 십전대보탕 전탕액 비교 연구)

  • Kim, Jung-Hoon;Seo, Chang-Seob;Jeon, Woo-Young;Shin, Hyeun-Kyoo
    • The Journal of Korean Obstetrics and Gynecology
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    • v.25 no.2
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    • pp.108-119
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    • 2012
  • Objectives: This study was performed to compare the differences between decoctions extracted by different extraction method and extraction time. Methods: Decoctions were prepared with pressurized or non-pressurized extraction for 60, 120 and 180min. The yield of extract, total soluble solid content, hydrogen ion concentration(pH) and the content of reference compound in Sipjeondaebo-tang (Siquandabu-tang) were investigated. Results: While yields and the total soluble solid of decoction were higher in pressurized method proportional to extraction time, pH values were lower in pressurized method and showed decreasing values with increasing extraction time. Albilflorin, ferulic acid, nodakenin, coumarin, cinnamaldehyde and glycyrrhizin were contained in decoctions by pressurized extraction method more than non-pressurized method whereas the content of coumarin was higher in decoctions by non-pressurized extraction method. In addition, coumarin was extracted increasingly with extraction time in decoctions by pressurized method, however, nine compounds except cinnamaldehyde showed the tendency of increasing proportional to extraction time. Conclusions: The results show that extraction methods including pressurized or non-pressurized extraction, and extraction time could affect the physicochemical characteristic or composition of Sipjeondaebo-tang(Siquandabu-tang) decoction.

Antioxidative Effect of Suaeda japonica Ethanol Extract and Solvent Partitioned Fractions (칠면초 추출물의 항산화 효과)

  • Lee, Kyung-Seok;Gim, Jae-Chun;Son, Seok-Min;Lee, Ki-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.6
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    • pp.804-808
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    • 2011
  • We studied the antioxidant activity of Suaedajaponica, found in Korean mud flats. A 70% ethanol extraction yielded 9.74%. The 70% ethanol extract was further fractionated with hexane, chloroform, ethyl acetate, butanol, and water. The water fraction resulted in the highest extraction yields, but the ethyl acetate fraction resulted in the highest total phenol content and also total flavonoid content. The antioxidative activity of the fractions was evaluated using several methods and compared to commercial antioxidants. The scavenging activities of the hydroxyl radical, hydrogen radical, hydrogen peroxide, and xanthine oxidase of the ethyl acetate fraction were equivalent to that of BHA. The scavenging activities of the hydroxyl radical, hydrogen peroxide, and xanthine oxidase of the ethanol extracts were approximately 80~90% of that of BHA.