• Title/Summary/Keyword: iodine reaction

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Optimization of hydrochar generated from real food waste using titration methods (음식물폐기물-하이드로촤 최적 반응조건 도출을 위한 적정법 응용)

  • Choi, Minseon;Choi, Seong-Eun;Han, Sol;Bae, Sunyoung
    • Analytical Science and Technology
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    • v.28 no.1
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    • pp.40-46
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    • 2015
  • Hydrochar has been generated from food waste via hydrothermal carbonization (HTC) reaction. As a solid product of HTC reaction, hydrochar has a great potential as an adsorbent of pollutants from the various media. The surface area and pore volumes are very important parameters to be served as an adsorbent. It requires an expensive equipment and consumes time to measure those parameter. Therefore, titration methods including iodine and methylene blue adsorption were evaluated to be correlated with that of BET analysis. Even though the absolute values of the computed surface area and pore volumes were not able to be matched directly, the patterns of change were successfully correlated. Among the reaction conditions, the reaction time and temperature at $230^{\circ}C$ for 4 h was determined as an optimization condition, which confirmed by titration method and BET analysis. Titration method for surface area and pore volumes computed by combination of iodine and methylene blue adsorbing values would be a simple and fast way of determining the optimization condition for hydrochar as an adsorbent produced by HTC reaction.

Changes of Linolenic Acid Content and Reactivity during Partial Hydrogenation of Soybean Oil with and without Lecithin (레시틴의 첨가 유, 무에 따른 대두유의 수소첨가 반응성과 리놀렌산의 변화)

  • Kwon, Hye-Soon
    • Korean Journal of Food Science and Technology
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    • v.27 no.1
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    • pp.41-46
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    • 1995
  • Changes of fatty acid composition and reaction rate were investigated according to reaction condition during partial hydrogenation reaction of soybean oil until its iodine value decreased from 134 to 110. The reaction conditions were varied in the range of from $170^{\circ}C$ to $210^{\circ}C$ of temperature, from 1.3 atm to 4.2 atm of pressure and from 0.005% to 0.1% of nickel concentration as catalyst. Lecithin was added in soybean oil to investigate the change of reaction rate. The result of addition of lecithin showed that reaction rate decreased to from 2 to 6 times in comparison with non-additive system.

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Studies on the Wastewater of General Hospital and It에s Treatment -Effects of Disinfectants on Activated Sludge Process- (病院廢水의 特性과 處理에 關한 硏究 -消毒劑가 활성스러지법에 미치는 영향-)

  • Ra, Kyu Hwan;Ok, Chi Sang
    • Journal of Environmental Health Sciences
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    • v.10 no.1
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    • pp.13-20
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    • 1984
  • The hospital wastewaters have to be so disposed as to prevent disease and to protect water resources from hazardous substances disinfectants, medicines, and chemicals. Polyvinylpyrrolidone-iodine complex (povidone-iodine) is widely used in the hospital as one of disinfectants. This study was carried out to manifest the effect of disinfectants in growth of activated sludge in treatment of the hospital wastewater by the activated sludge process. The results are as follow. 1. An average water quality of the hospital wastewater showed 7.2 in pH, 3.2 ppm in DO, 293.3 ppm in SS, 96.0 ppm in BOD, 151.1 ppm in COD, 0.4 ppm in povidone-iodine, 0.5 ppm in phenols, 5.4 ppm in surfactants, 1.6 ppm in o-phosphate, 4.6 ppm in $NH_3-N, 249\times 10^4$ counts/100 ml in coliform group organisms, and $1,369\times 10^2$ counts/ml in general counts of bacteria. And wastewater amounts discharged per bed was calculated 70 l/d/bed. 2. In batch culture activated sludge process, each of cresol and povidone-iodine was not effected in less than 0.1 ppm concentration, but the more concentration, the more inhibit the growth rate of activated sludge. In the mixture of two disinfectants, the growth was more inhibited the effect of single disinfectants. So that this reaction is considered as addition effect of two disinfectants. 3. The removal rates of the disinfectants-by continuous culture activated sludge process were 77.6% in 0.4 ppm povidone-iodine, and in BOD was 85.6%. 4. It is desirable that the hospital wastewater is planed in order to be discharged to two system separately, sewer from life system and wastewater from medical system. From those results, it has been concluded that the hospital wastewater has to be treated safely by the activated sludge process.

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Numerical Study on Heat Transfer Characteristics in a directly Heated $SO_3$ Decomposer for the Sulfur-Iodine process (황-요오드 공정용 직접접촉 삼산화황 분해반응기내 열전달 특성에 관한 수치적 연구)

  • Choi, Jae-Hyuk;Shin, Young-Joon;Tak, Nam-Il;Lee, Ki-Young;Chang, Jong-Wha;Chung, Suk-Ho
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.2244-2249
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    • 2007
  • A directly heated $SO_3$ decomposer for the sulfur-iodine and hybrid-sulfur processes has been introduced and analyzed by using a computational fluid dynamics code(CFD) with the CFX 5.7.1. The use of a directly heated decomposition reactor in conjunction with a VHTR allows higher decomposition reactor operating temperature. However, the thermochemical and hybrid hydrogen production processes accompanied with the high temperature and strongly corrosive operating conditions basically have material problems. In order to resolve these problems, we carried out the development of a structural material and equipment design technologies. The results show that the maximum temperature of the structural material (RA330) could be maintained at 800$^{\circ}C$ or less. Also, it can be seen that the mean temperature of the reaction region packed with catalysts in the $SO_3$ decomposition reactor could satisfy the temperature condition of around 850 $^{\circ}C$ which is the target temperature in this study.

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A Study on the Development of Activated Carbon from Rice-Hull (왕겨를 이용한 활성탄 개발에 관한 연구 (I))

  • 이희자;조양석;조광명
    • Journal of Environmental Science International
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    • v.9 no.1
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    • pp.81-88
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    • 2000
  • Every year, 1.1 million tons of rice-hull are produced in South Korea by the by-product in pounding rice. But they has mainly been utilized as a fuel, agricultural compost and moisture proofs. So, it's very valuable to use waste rice-hull for activated carbon manufacture. SiO2 content was the highest among inorganics in rice-hull. Therefore, the SiO2 extraction experiments were carried out under the various conditions of pH 9 to 14, reaction time from 2 to 24 hrs and various temperature of 20 to 100℃. The results showed that increase in pH and temperature enhanced SiO2 extraction from the carbonized rice-hull. The surface area of the carbonized rice-hull indicating activated carbon adsorption capacity was very small as 178∼191 m2/g at first. However, it was increased to 610∼675 m2/g when extracted in alkali solution at 100℃. When the mixing rate of carbonized rice-hull and NaOH was 1:1.5, iodine No. and surface area of activated rice-hull during 10 min at 700℃ were 1,650 mg/g and 1837 m2/g, respectively. Subsequently, an activated carbon with specific surface area of 1,300∼1,900m2/g was manufactured in a short contact time of 10∼30 min with a mixing rate of 1:1.5 in carbonized rice-hull and NaOH, and iodine No. and specific surface area increased as the amount of SiO2 removal increased.

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A Straightforward Synthesis of K-7174, a GATA-Specific Inhibitor

  • Majik, Mahesh S.;Yu, Jin-Ha;Jeong, Lak-Shin
    • Bulletin of the Korean Chemical Society
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    • v.33 no.9
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    • pp.2903-2906
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    • 2012
  • K-7174, a GATA-specific inhibitor, is a putative anti-inflammatory agent that attenuates effects of inflammatory cytokines in certain cell types. An expeditious four-step synthesis of K-7174 is described in this paper. The route employs Wittig olefination and bis-alkylation of homopiperazine as the key reactions. The iodine-catalyzed isomerization of the Z-isomer results in complete conversion to the E-isomer is the highlight of our synthetic endeavors.

The Oxidative Iodination of Pyrimidine Bases and their Nucleosides using Iodine/Dimethylformamide/m-Chloroperbenzoic Acid

  • Hwang, Chang-Ho;Park, Jung-Sup;Won, Jeong-Hee;Kim, Jae-Nyoung;Ryu, Eung K.
    • Archives of Pharmacal Research
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    • v.15 no.1
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    • pp.69-72
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    • 1992
  • Pyrimidine bases and their mucleosides were oxidatively iodinated at C-5 position by the reaction of iodine in DMF (dimethylformamide) with MCPBA (m-chloroperbenzoic acid) under mild conditions. For uracil derivatives such as uracil 1a. 1, 3-dimethyluracil 1b, uridine 1c, and 2'-deoxyuridine 1d, the corresponding 5-iodo derivatives were obtained in high yields (71-95%). The iodination of cytidine 3a and 2'-deoxycytidine 3b was achieved in moderate yields (41-56%).

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Ailanthoidol Derivatives and their Anti-inflammatory Effects

  • Lee, Na-Li;Lee, Jae-Jun;Kim, Jin-Kyung;Jun, Jong-Gab
    • Bulletin of the Korean Chemical Society
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    • v.33 no.6
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    • pp.1907-1912
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    • 2012
  • Ailanthoidol showed a strong $anti$-inflammatory effect in a previous result. Ailanthoidol derivatives were prepared for the $anti$-inflammatory test using Sonogashira coupling, iodine induced cyclization and Wittig reaction. $Anti$-inflammatory effects of the prepared ailanthoidol derivatives were examined in lipopolysaccharide (LPS)-stimulated RAW 264-7 macrophages. The results showed that some ailanthoidol derivatives inhibited significantly the production of inflammatory mediator nitric oxide.

TWO-DIMENSIONAL SIMULATION OF HYDROGEN IODIDE DECOMPOSITION REACTION USING FLUENT CODE FOR HYDROGEN PRODUCTION USING NUCLEAR TECHNOLOGY

  • CHOI, JUNG-SIK;SHIN, YOUNG-JOON;LEE, KI-YOUNG;CHOI, JAE-HYUK
    • Nuclear Engineering and Technology
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    • v.47 no.4
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    • pp.424-433
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    • 2015
  • The operating characteristics of hydrogen iodide (HI) decomposition for hydrogen production were investigated using the commercial computational fluid dynamics code, and various factors, such as hydrogen production, heat of reaction, and temperature distribution, were studied to compare device performance with that expected for device development. Hydrogen production increased with an increase of the surface-to-volume (STV) ratio. With an increase of hydrogen production, the reaction heat increased. The internal pressure and velocity of the HI decomposer were estimated through pressure drop and reducing velocity from the preheating zone. The mass of $H_2O$ was independent of the STV ratio, whereas that of HI decreased with increasing STV ratio.

Evaluation of a Waterless, Scrubless Chlorhexidine Gluconate/Ethanol Surgical Scrub and Povidone-Iodine for Antimicrobial Efficacy (물과 솔 없이 사용하는 외과적 손 소독제 Chlorhexidine/Ethanol 혼합제와 Povidone-iodine의 소독 효과)

  • Choi, Jeong-Sil
    • Journal of Korean Academy of Nursing
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    • v.38 no.1
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    • pp.39-44
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    • 2008
  • Purpose: The purpose of this study was to compare 1% chlorhexidine-gluconate/61% ethanol (CHG/Ethanol) emollient and 7.5% povidone-iodine (PVI) scrub for antimicrobial, residual effect, and skin condition. Method: CHG/Ethanol emollient hand hygiene was performed waterless, and brushless by operating doctors and nurses (N=20). PVI hand washing was performed with water and a brush (N=20) for 5 min. The subjects were asked to press their left hand in hand-shaped agar before a surgical scrub, immediately after a surgical scrub and after the operation. The amount of isolated microorganisms were calculated by counting the number of divided areas($1{\times}1cm$, 160 cell) which were culture positive in the hand culture plate. The skin condition was evaluated. Result: The antimicrobial count of CHG/Ethanol emollient and PVI immediately post surgical scrub was 0.0 vs. 4.1 (p>.05), and after the operation was 0.1 vs. 37.8 (p>.05)respectively. The Residual effect of CHG/Ethanol emollient immediately post surgical scrub and after the operation were 0.0 vs. 0.1 (p>.05), and PVI were 4.1 vs. 37.8 (p>.05)respectively. The skin condition and satisfaction of CHG/Ethanol emollient was higher than PVI (p<.05). Conclusion: The antimicrobial effect between CHG/Ethanol emollient and PVI were the same. Considering skin condition, satisfaction and allergic reaction CHG/Ethanol emollient for surgical scrub is recommended in Korea.