• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.524-527
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• 2000

An electroenzymatic system to oxidize veratryl alcohol of on electrodes with in-situ generated hydrogen peroxide was studied. We investigated hydrogen peroxide generation, current efficiency, and veratryl alcohol oxidation in the electrode system at various conditions. The reaction rates of veratryl alcohol oxidation were compared in an electrochemical, an electroenzymatic, and an usual biochemical systems to prove the concept of electroenzymatic oxidation.

• Journal of Electrochemical Science and Technology
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• 제15권1호
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• pp.67-95
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• 2024

Direct alcohol fuel cells (DAFCs) have gained much attention as promising energy conversion devices due to their ability to utilize alcohol as a fuel source. In this regard, Molybdenum-based electrocatalysts (Mo-ECs) have emerged as a substitution for expensive Pt and Ru-based co-catalyst electrode materials in DAFCs, owing to their unique electrochemical properties useful for alcohol oxidation. The catalytic activity of Mo-ECs displays an increase in alcohol oxidation current density by several folds to 1000-2000 mA mg_Pt^-1, compared to commercial Pt and PtRu catalysts of 10-100 mA mg_Pt^-1. In addition, the methanol oxidation peak and onset potential have been significantly reduced by 100-200 mV and 0.5-0.6 V, respectively. The performance of Mo-ECs in both acidic and alkaline media has shown the potential to significantly reduce the Pt loading. This review aims to provide a comprehensive overview of the bifunctional mechanism involved in the oxidation of alcohols and factors affecting the electrocatalytic oxidation of alcohol, such as synthesis method, structural properties, and catalytic support materials. Furthermore, the challenges and prospects of Mo-ECs for DAFCs anode materials are discussed. This in-depth review serves as valuable insight toward enhancing the performance and efficiency of DAFC by employing Mo-ECs.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.160.3-161
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• 2003

Aldehyde and active form of free oxygen produced in alcohol metabolism in liver are the cause of liver cell damage. The main system of alcohol metabolism is composed of alcohol dehydrogenase(ADH), aldehyde dehydrogenase(ALDH) and cytochrome P4502E1. Alcohol dehydrogenase is reversible in alcohol metabolism. To block the backward reaction and enhance alcohol oxidation, acetaldehyde trapping agents were assayed. The assay was carried out by measuring decreasing NADH at 340nm, using acetaldcehyde and NADH as substrate and coenzyme respectively. (omitted)

• 한국응용과학기술학회지
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• 제20권2호
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• pp.141-147
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• 2003

Oxidized polyethylene wax is obtained by oxidation of polyethylene wax and it is composed of various chemicals, e.g., fatty acid, alcohol, ketone and ester. The application of oxidized polyethylene wax is determined by the composition of these chemical substances. In this basic study we observed the basic reaction parameters of time, temperature, oxygen concentration and catalysts on the oxidation reaction of low molecular weight polyethylene(PE wax) by analyzing the acid value, physical and chemical properties of oxidized PE wax to develop a new oxidation process. Acid values are increased with temperature increase in the rage of $150^{\circ}C^{\sim}180^{\circ}C$ but decreased beyond 190$^{\circ}C$. Acid values are also increased with oxygen concentration. As the oxidation reaction proceeds the molecular weight and softening points of oxidation products are decreased by cracking reaction, but the viscosities are increased. To observe the crystallinity of oxidation products SEM experiment was performed. To obtain a high acid-value product in a mild condition, we adopted free radical catalysts and the acid value of the product using catalyst was higher than the product obtained without catalyst in the same reaction condition. The effective initiators were dicumyl peroxide(DCPO), t-butylperoxy-2-ethyl hexanoate(HOPO) and benzoyl peroxide(BPO) having long half-life.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1203-1205
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• 2006

During the synthesis of 4-fluorobenzaldehyde via the SNAr reaction of 4-nitrobenzaldehyde with TBAF, it was found that an equivalent amount of TBAF could oxidize benzaldehyde to benzoic acid. The reaction of 4-nitrobenzaldehyde with tetrabutylammonium fluoride (TBAF) gave 4-nitrobenzoic acid in high yield. Depending on the reaction conditions, other aromatic aldehydes produced acids with fewer amounts of alcohols. However, this type of oxidation has limited practical applications. Nevertheless, the mechanism is quite different from the Cannizzaro reaction because the amounts of the acid salt and alcohol formed were different.

• Bulletin of the Korean Chemical Society
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• 제22권9호
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• pp.943-944
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• 2001

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.3003-3008
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• 2011

Reactions of benzyl alcohol and its derivatives by [Ru$^{IV}$(tpy)(dcbpy)(O)]$^{2+}$ (tpy = 2,2':6',2"-terpyridine; dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) leading to the corresponding benzaldehydes in acetonitrile and water have been studied. Kinetic studies show that the reaction is first-order in both alcohol and oxidant, with k = 1.65 (${\pm}$ 0.1) $M^{-1}s^{-1}$ at $20^{\circ}C$, ${\Delta}H^{\ddag}$ = 4.3 (${\pm}$ 0.1) kcal/mol, ${\Delta}S^{\ddag}$ = -22 (${\pm}$ 1) eu, and $E_a$ = 4.9 (${\pm}$ 0.1) kcal/mol. High ${\alpha}$ C-H kinetic isotope effects are observed, but O-H solvent isotope effects are negligible. Spectral evidences with the isotope effects suggest that oxidation of benzyl alcohols occurs by a two-electron, hydride transfer. The catalytic cycles of aerobic benzyl alcohol oxidation are employed.

• 공업화학
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• 제25권3호
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• pp.281-285
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• 2014

호기성 벤질 알코올 산화반응용 촉매로 팔라듐이 담지된 이산화티타늄 입자를 제조하였다. 우선 합성한 이산화티타늄입자에 10 wt% 팔라듐을 함침한 후, 다양한 온도에서 소성하여 촉매를 제조하였다. 촉매의 비표면적은 소성온도에 따라 변하였는데, $300^{\circ}C$에서 소성한 촉매의 비표면적이 가장 높게 측정되었다. 제조된 촉매의 반응 결과 $300^{\circ}C$에서 소성한 입자가 가장 우수한 반응성능을 보였다. 또한 팔라듐의 농도를 5 wt%에서 15 wt%까지 조절하여 함침한 후 $300^{\circ}C$에서 소성하여 촉매를 합성하였다. 팔라듐의 농도가 10 wt%인 $Pd/TiO_2$ 입자가 벤질알코올 산화반응에 최적의 촉매로 규명되었다. 이는 상대적으로 높은 촉매의 비표면적 및 팔라듐 분산도에 기인한다.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2748-2752
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• 2012

Cr(III) and Co(III) complexes with acetylacetonate were anchored onto a mesoporous MCM-41 through Schiff condensation. The materials were characterized by XRD, FT-IR, BET, CHN and ICP techniques. Elemental analysis of samples revealed that one C=N bond was formed through Schiff condensation on MCM-41 surface. The catalysts were tested for the alcohol oxidations using t-butyl hydroperoxide (TBHP) and $H_2O_2$ as oxidant. The catalytic experiments were carried out at both room temperature and reflux condition. Various solvents such as dichloromethane, acetonitrile and water were examined in the oxidation of alcohols. Among the different solvents, catalytic activity is found more in acetonitrile. Further, the catalysts were recycled three times in the oxidation of alcohols and no major change in the conversion and selectivity is observed, which shows that the immobilized metal-acetylacetonate complexes are stable under the present reaction conditions.

• 공업화학
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• 제33권4호
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• pp.436-439
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• 2022

벤질알코올의 전기화학적 산화를 통해 𝛽-hydroxynitrile과 𝛽-ketonitrile을 합성하였다. 이 생성물은 용매인 아세토나이트릴이 전기화학적으로 환원되어 생성된 아세토나이트릴 음이온과 벤질알코올이 산화된 벤즈알데하이드의 첨가반응을 통해 생성되었을 것이라고 예상된다. 그리고 20 mA의 전류를 3 h 인가하였을 때, cyanomethylation를 통해 생성된 𝛽-hydroxynitrile이 전기화학적으로 산화되어 최종적으로 𝛽-ketonitrile이 합성됨을 확인하였다. 본 연구에서는 상온에서 가장 범용적으로 사용되는 백금 전극을 이용하여 벤질알코올을 전기화학적으로 𝛽-hydroxynitrile 또는 𝛽-ketonitrile로 합성하는 것이 가능한 것을 입증하였다.