• Title, Summary, Keyword: ketone

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Effect of Spreading of Neutral Sizing Agent, Alkylketene Dimer, on Sizing Development

  • Seo Won-Sung;Shin Jong-Ho;Cho Nam-Seok
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.37 no.5
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    • pp.1-7
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    • 2005
  • The objective of this work was to investigate the effect of spreading behavior of the sizing agents (AKD or dialkyl ketone) on the sizing development of AKD-sized paper. There was a direct relationship between the spreading behavior of the sizing agents and their melting points. Both AKD and dialkyl ketone showed no substantial spreading until the temperature reaches to their melting points. Consequently, dialkyl ketone did not provide sizing development when the paper was heat-treated below $75^{\circ}C$, while AKD provided sizing effect even the paper heated at $50^{\circ}C$. The ketone, however, provided rather higher sizing effect than that of AKD, when the paper was heat-treated over $100^{\circ}C$. This result means that the ketone also gives sizing development to paper, moreover the ketone could give higher sizing effect to paper than AKD when it was melted and well spreaded on the fiber surface. While the ketone introduced to papers from hydrolyzed AKD emulsion could not contribute to sizing development.

Singlet-Triplet Reactivity of 1-Methyl-2-Cyclohexenyl Aryl Ketones : Racemization vs 1,3-Acyl Shift in the Excited States

  • Woo Ki Chae;Mi Young Chae;Mi Kyung Park;Chung Hee Lee;Eun Hee You
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.241-244
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    • 1990
  • The photochemistry of 1-Methyl-2-cyclohexenyl aryl ketones (phenyl ketone 7a, p-toluyl ketone 7b, biphenyl ketone 7c and -naphthyl ketone 7d) is reported. The aryl ketone 7a, 7b and 7c undergo photo-racemization with efficiencies of 0.75, 0.79 and 0.76 respectively on direct irradiation. Direct irradiation of the ketone 7d, however, undergoes 1,3-shift with an efficiency of 0.02. Triplet states are responsible for the racemizations and singlet state is responsible for 1,3-shift as in general. The ketone 7a, 7b and 7c are good example of a few ${\beta},{\gamma}$-unsaturated ketones which undergo efficient intersystem crossing on direct irradiation.

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C-C Bond Cleavage of 8-Quinolinyl Alkyl Ketone by $\sigma,\eta^{3-}$-Allyl Rhodium(III) Complex

  • 이대윤;임영권;전철호
    • Bulletin of the Korean Chemical Society
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    • v.18 no.8
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    • pp.824-827
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    • 1997
  • Bis(ethylene)rhodium(Ⅰ) chloride dimer reacted with vinylcyclopropane to give σ,η3-allylrhodium(Ⅲ) complex 3. Complex 3 underwent C-C bond cleavage of 8-quinolinyl ethyl ketone 11, to form η3-1,3-dimethylallylrhodium(Ⅲ) complex 8, which was reductively eliminated by trimethyl phosphite to give 8-quinolinyl-1-methylbut-2-enyl ketone (10). More sterically hindered 8-quinolinyl alkyl ketones were allowed to react with complex 3 to afford corresponding alkenes as well as a mixture of complex 8 and η3-1-ethylallyl rhodium(Ⅲ) complex 19, identified as 10 and 8-quinolinyl-pent-2-enyl ketone (20) after reductive elimination. 8-Quinolinyl alkyl ketone bearing a sterically hindered alkyl group showed less reactivity for C-C bond cleavage and higher 20/10 ratio compared with those having a less sterically hindered alkyl group, such as 8-quinolinyl ethyl ketone (11).

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The Synthesis of 2-Furyltriisopropoxytitanium and its Reactivity to Carbonyl Compounds (2-Furytriisopropoxytitanium의 합성 및 카르보닐 화합물에 대한 반응성)

  • Koo, Doo-Hyo;Kyung, Suk-Hun
    • Applied Biological Chemistry
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    • v.39 no.4
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    • pp.309-314
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    • 1996
  • 2-Furyltriisopropoxytitanium was synthesized in situ through transmetallation of 2-furyllithium with chlorotitaniumtriisopropoxide. The compound could be isolated at room temperature and preserved at $-10^{\circ}C$ for several weeks. The reactivity 2-furyltriisopropoxytitanium to carbonyl compounds proved to be high. A complete aldehyde selectivity was observed in competition reactions of 2-furyltriisopropoxytitanium with a 1:1 mixture of aldehyde and ketone. In competition reactions of 2-furyltriisopropoxytitanium with a 1 : 1 mixture of ketone and ketone, the degree of ketone / ketone discrimination was substantial. In the reaction of 2-furyltriisopropoxytitanium to ketone-ester function, the reagent was solely reacted with the ketone function.

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A Study for the Standardization of Elsholtzia ciliata (Thunb.) Hylander and Elsholtzia splendens Nakai ex F. Maekawa

  • Yun, Jong-Seong;Lee, Sang-In;Rhee, Jae-Seong;Park, Ho-Koon
    • The Journal of Korean Medicine
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    • v.19 no.1
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    • pp.19-26
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    • 1998
  • The purpose of present study is to clarify the differences between EIslwitzia Ciliata (Thunb.) Hylander(향유) and Elsholtzia splendens Nakai ex F. Maekawa (꽃향유) for standardization and the proper usage as medicinal herbs. The major ingredients of both species were isolated by distillation and extraction. The qualitative and quantitative analyses of major distillates were carried out by the use of GC/MS. There was a significant difference between the components of Elsholtzia ciliata and Elsholtzia splendens in the aspects of major components. Several common ingredients were identified as linalool, cumene, elsholtzia ketone, naginata ketone isomer, naginata ketone, myristicin, and sesquiterpene alcohol. Comparison between Elsholtzia. ciliata and Elsholtzia splendens was done in the aspect of major compounds. Myristicin (33.7%) has been shown to be the major component in Elsholtzia ciliata whereas naginata ketone isomer (26.1%) was believed to be a major ingredient in Elsholtzia splendens. The elsholtzia ketone was also one of the major differentiating factors between Elsholtzia splendens and Elsholtzia ciliata, and the quantity is 15.1% in Elslwltzia splendens compared to 2.87% in Elsholtzia ciliata. Moreover, in the Elsholtzia splendens, 4- vinylguaiacol and isoosmorhizole were absent, but both compounds were present in the EIsholtzia ciliata.

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The Effect of Iron Catalysts on the Formation of Alcohol and Ketone in the Biomimetic Oxidation of Cyclohexane

  • Kim Seong-Bo;Lee Kyu-Wan;Kim, Yong-Joon;Hong Seog-In
    • Bulletin of the Korean Chemical Society
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    • v.15 no.6
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    • pp.424-427
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    • 1994
  • Effects of iron compounds in known biomimetic oxidation systems (Gif IV and GoAgg II) have been studied on activity and ketone/alcohol selectivity of cyclohexane oxidation. Both ketone/alcohol ratio and cyclohexane conversion were affected by counter-ion Z of iron compounds Z-Fe. When Z has a more electron withdrawing property, the reactivity is increased and the formation of ketone is favored. From these experimental results, a new mechanism is proposed for the biomimetic oxidation system.

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cis-trans Isomeric and Substituent Effects on the Lanthanide Induced Shifts in 2-Phenylcyclopropanic System

  • So, Jung-Ho;Cho, Nam-Sook
    • Bulletin of the Korean Chemical Society
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    • v.5 no.6
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    • pp.226-230
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    • 1984
  • LIS's of cis and trans-methyl-2-phenylcyclopropanecarboxylate, cis and trans-t-butyl-2-phenylcyclopropanecarboxylate, cis and trans-N,N-dimethylcyclopropanecarboxamide, trans-2-phenylcyclopropyl methyl ketone and trans-2-phenylcyclopropyl t-butyl ketone have been studied. The LIS's hold the McConnell-Robertson relation and are mainly influenced by the steric effect. LIS's of trans isomers are larger than those of cis isomers. In trans isomers, the LIS's decrease in the following order: methyl ketone > methyl ester > N,N-dimethyl amide > t-butyl ketone${\sim}$t-butyl ester.

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A Study on the Characteristics of Pyrolysis of Methyl Ethyl Ketone Peroxide with Addition of Sulfuric Acid (황산의 첨가에 따른 Methyl Ethyl Ketone Peroxide의 열분해 특성에 관한 연구)

  • Jung Doo-Kyun;Choi Jae-Wook;Lee In-Sik
    • Fire Science and Engineering
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    • v.18 no.4
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    • pp.52-56
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    • 2004
  • An experiment to examine the characteristics of pyrolysis of Methyl Ethyl Ketone Peroxide was conducted in an air-present environment, using TG-DTA. Decomposition starting temperature was decreased as the increase of 98% concentrated H₂SO₄ to the MEKPO and the maximum decomposition temperature of MEKPO was 116.8℃. The activated energy calculated from differential method of pure MEKPO, MEKPO with 1 wt%, 3wt%, and 5wt% of H₂SO₄ were 0.576㎉/mo1, 0.355㎉/㏖, 0.284㎉/㏖ and 0.258㎉/㏖ respectively.

Characterization of Polymer Blends of Poly(ether sulfone)/Sulfonated Poly(ether ether ketone) for DMFC (직접메탄올 연료전지용 Poly(ether sulfone)/Sulfonated Poly(ether ether ketone) 블렌드 막의 특성 연구)

  • Cheon, Hun Sang;Lee, Choong Gon;Hong, Seong Uk
    • Applied Chemistry for Engineering
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    • v.16 no.1
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    • pp.144-149
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    • 2005
  • Sulfonated poly(ether ether ketone) (SPEEK) was blended with poly(ether sulfone) (PES) at various compositions. To investigate the possibility of using the blend membranes as polymer electrolyte membranes for direct methanol fuel cell, the blend membranes were characterized in terms of methanol permeability, proton conductivity, ion exchange capacity, and water content. Both proton conductivity and methanol permeability of SPEEK were relatively high. As the amount of PES increased, methanol permeability decreased more rapidly compared to proton conductivity. The experimental results indicated that the blend membrane with 40 wt% PES was the best choice in terms of the ratio of proton conductivity to methanol permeability.

The Effectiveness of Blood β-ketone Testing in Patients with Diabetic Ketosis: A Systematic Review & Meta-analysis (당뇨환자에서 자가관리형 베타케톤검사의 유효성: 체계적 문헌 고찰 및 메타분석)

  • Mo, Jin A;Jang, Sunyoung;Bang, Hee Young
    • Korean Journal of Health Education and Promotion
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    • v.31 no.4
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    • pp.1-10
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    • 2014
  • Objectives: The effectiveness of Blood ${\beta}$-ketone testing by using self-monitoring strip on diabetic patients. Methods: Clinical effectiveness of blood ${\beta}$-ketone testing was assessed through correlation with reference test that measured blood ${\beta}$-ketone value through gas chromatography or enzyme method, diagnostic accuracy, time taken for the test and time taken for confirmative diagnosis of diabetic ketosis by selecting literatures on researches that conducted this test on ketosis(suspected) patients or diabetic ketosis(suspected) patients. Each of the stages from literature search to application of selection standards and extraction of data were carried out independently by the Subcommittee along with 2 researchers. Results: 7 reports were selected. ${\beta}$-ketone testing displayed high level of correlation in the range of r=0.92~0.99 with test using enzyme method as the reference standard. Regarding the diagnostic accuracy, sensitivity of 0.82, specificity of 0.74. The time taken for the test was 30seconds for the index test, which is shorter than reference standard test. Conclusion: Blood ${\beta}$-ketone testing was assessed to be a safe and effective test to monitor ketosis and assess the level of risk of ketosis by measuring the blood ${\beta}$-ketone on ketosis patients and diabetic ketosis patients since it has high level of correlation with reference test and short period of testing.