• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.153-157
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• 2005

4-(Dimethylamino)pyridinium dichromate was synthesized by the reaction of 4-(dimethylamino)pyridine with chromium(VI)trioxide in $H_2O$, and characterized by IR, EA and ICP. The oxidation of benzyl alcohol using 4-(dimethylamino)pyridinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant, in the order: cyclohexen < chloroform < acetone < N,N-dimethylformamide. In the presence of hydrochloric acid(HCl), 4-(dimethylamino)pyridinium dichromate oxidized benzyl alcohol and its derivatives ($p-CH_3$, H, m-Br, $m-NO_2$) smoothly in N,N-dimethylformamide. Electron-donating substituents accelerated the reaction, whereas electron-withdrawing groups retarded the reaction. The Hammett reaction constant($\rho$) was -0.70 at 303K. The observed experimental data have been rationalized as follows: the proton transfer occurs after the prior formation of a chromate ester in the rate-determining step.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.6039-6046
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• 2013

Cr(VI)-heterocyclic complex[Cr(VI)-2-methylpyrazine] was synthesized by the reaction between of heterocyclic compound(2-methylpyrazine) and chromium trioxide, and characterized by IR and ICP analysis. The oxidation of benzyl alcohol using Cr(VI)-2-methylpyrazine in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order : cyclohexene${\rho}$) was Cr(VI)-2-methylpyrazine= -0.65(308K). The observed experimental data have been ratiolized. The hydride ion transfer causes the prior formation of a chromate ester in the rate-determining step.

• Analytical Science and Technology
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• v.11 no.3
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• pp.222-228
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• 1998

Five kinds of packed column and two kinds of capillary column were used to get optimum condition for ethanol analysis by using fifteen different volatile, low molecular weight organic substances. Only two columns, Gaskuropack 54 and DB-1, showed good separation efficiency. In the adding salt-effect experiment 0.6N - perchloric acid, 1M - meta-phosphoric acid and saturated NaCl solution were used for alcohol concentration measurement of biological fluids and tissue specimens. Among adding salt experiment, adding saturated NaCl solution showed the most stable value of alcohol concentration. This fact might be due to the increased vaporization of alcohol in the saturated NaCl solution. In the time-course of blood alcohol concentration, the alcohol level was lineary decreased to the diameter of vessel containing specimens. This result was interpreted in view of ethanol level, weight, water content, and hematocrit value. The ethanol distribution levels were measured from samples of blood and tissue obtained from 25 postmortems cases investigated by NISI. This study showed that the distribution level was decreased in order of brain, blood, kidney, spleen, liver, and lung.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5990-5996
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• 2011

6-Methylquinolinium dichromate[$(C_{10}H_9NH)_2Cr_2O_7$] was synthesized by the reaction of 6-methylquinoline with chromium trioxide in $H_2O$, and characterized by IR, ICP. The oxidation of benzyl alcohol using 6-methylquinolinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order: cyclohexene < chloroform < acetone < N,N- dimethylformamide. In the presence of hydrochloric acid($H_2SO_4$ solution), 6-methylquinolinium dichromate oxidized benzyl alcohol and its derivatives(p-$OCH_3$, m-$CH_3$, H, m-$OCH_3$, m-Cl, m-$NO_2$) smoothly in DMF. Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant(${\rho}$) was -0.67(303K). The observed experimental data was used to rationalize the hydride ion transfer in the rate-determining step.

• Applied Chemistry for Engineering
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• v.23 no.2
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• pp.241-246
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• 2012

Cr(VI)-heterocyclic complex (2,2'-bipyridinium dichromate) was synthesized by the reaction between of 2,2'-bipyridine and chromium trioxide in $H_2O$, and characterized by IR and ICP. The oxidation of benzyl alcohol using 2,2'-bipyridinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant, in the order: cyclohexene < chloroform < acetone < N,N-dimethylformamide. In the presence of DMF solvent with acidic catalyst such as $H_2SO_4$ solution, 2,2'-bipyridinium dichromate oxidized the benzyl alcohol and its derivatives (p-$p-OCH_3$, $m-CH_3$, H, $m-OCH_3$, m-Cl, $m-NO_2$). Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant was -0.66 (303 K). The observed experimental data was used to rationalize the hydride ion transfer in the rate-determining step.

• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.718-722
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• 2011

2,4'-Bipyridinium dichromate [$(C_{10}H_8N_2H)_2Cr_2O_7$] was synthesized by the reaction of 2,4'-bipyridinie with chromium trioxide in $H_2O$. The structure was characterized by IR and ICP analysis. The oxidation of benzyl alcohol using 2,4'-bipyridinium dichromate in various solvents showed that the reactivity increased with the increase in the order of the dielectric constant (${\varepsilon}$), in the order : cyclohexene < chloroform < acetone < N,N'-dimethylformamide. In the presence of hydrochloric acid, 2,4'-bipyridinium dichromate effectively oxidized benzyl alcohol and its derivatives ($p-CH_3$, H, m-Br, $m-NO_2$) in N,N'-dimethylformamide. Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant (${\rho}$) was -0.65 at 303 K. The observed experimental data was used to rationalize the hydride ion transfer in the rate-determining step.

• Analytical Science and Technology
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• v.7 no.1
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• pp.125-132
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• 1994

Flavours in kimchee are the result of unique combination of various sugars, organic acids and amino acids as well as various volatile organic compounds including sulfur-containing compounds, terpenes, alcohols, and some volatile organic acids. In the experiment for the flavour extracting methods, dynamic headspace(DHS) is more effective for collection of volatile flavour than simultaneous distillation extraction(SDE). The best polarity available at the moment is 5% phenyl methyl poly-siloxane which will separate non-polar, intermediate and polar components with good resolution.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.115-118
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• 2006

The partitioning tracer method has been studied as an alternative method for characterizing aquifers contaminated by nonaqueous phase liquids (NAPLs). Accurate partition coefficients of tracers partitioning between NAPL and water are needed to improve the reliability of the partitioning tracer method. In this research, partition coefficients of alcohol tracers partitioning between benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds and water are estimated from using the approach of equivalent alkane carbon number (EACN). General agreement was observed in between the measured and estimated partition coefficients. Based on these results we can verify that the EACN approach is suitable for estimating the partition coefficient.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.220.1-220
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• 2003

전분질원으로서 밀가루와 찹쌀을 단용 (A : 전량 밀가루 사용, D： 전량 찹쌀 사용) 또는 혼용(B: 밀가루 75%, 찹쌀 25%, C: 밀가루와 찹쌀을 각 50%사용)하여 담금한 고추장의 성분을 분석 한 결과는 다음과 같다. 숙성과정중 조단백질과 아미노태의 질소함량은 대체적으로 A,B,C,Drn의 순으로 높았고, ethyl alcohol은 D,C,B,A 구의 순으로 높았다. pH는 A 구에서 다소 높았으나 수분과 식염은 시험구간에 차이가 없었다. 90일 숙성 고추장중의 유리당은 glucose, fructose, maltose, rhamnose가 검출되었고, 이중 glucose는 양적으로 가장 많았다. 또한 glucose는 A 구에서, fructose는 B 구에서 각각 높았다. 숙성고추장의 알코올류로서 n-propyl, iso-buthyl, iso-amyl alcohol이 검출되었으며, 이들 함량은 3.2mg%이하로 시험구간에는 큰 차가 없었다.

• Proceedings of the Membrane Society of Korea Conference
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• 1992.10a
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• pp.57-58
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• 1992

분리막을 이용한 물질의 분리는 최근 들어 많은 연구가 수행되어 일부 실용화 되고 있으나, 최근에 관심을 끌고 있는 Pervaporation 분리법에 의한 유기물의 분리는 여러가지 이유에서 아직 큰 성과를 올리지 못하고 있다고 생각된다. 그러나, 이 방법만이 갖는 잇점 때문에 국내.외에서 다방면으로 활발히 연구가 진행되고 있다. 한편 Pervaporation 분리법의 분리기구를 규명하는데는 많은 어려움이 있으므로 아직까지 명확히 밝혀지지 않고 있으나 언제인가는 밝혀져야 할 과제라고 생각된다. 따라서 본 연구에서는 투과현상을 좀 더 구체적으로 파악하므로써 분리기구를 해석하는 데 다소나마 기여하기 위하여 물 선택성 막은 Carboxy-methylcellulose(CMC) 막을 제작하여 알코올류, DMF, DMAc, Dioxane등의 유기 수용액의 분리실험을 하였으며, 투과 증기의 조성을 짧은 시간 간격으로 측정하므로써 분리특성과 아울러 투과현상을 파악하였다.