• Archives of Pharmacal Research
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• v.9 no.4
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• pp.229-232
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• 1986

Three inexpensive oxidation reagents, namely pyridinium chlorochromate, chromium trioxide-dipyridine and nicotinium dichromate were utilized for oxidation of carbohydrates in 78-92% yield. Hydration could be eliminated in the oxidation of pentopyranosides and hexopyranosides, while pentofuranosides had a tendency to be easily hydrated during the oxidation. In the carbon-13 n. m. r. study, the carbonyl function resulted from the oxidation affected on the chemical shifts of $\alpha$- and $\beta$-carbons of methyl 3. 4-O-isopropylidene-$\beta$-D-arabinopyranosid-2-ulose (8) and 1,2 : 4, 5-di-O-isopropylidene-$\beta$-D-erythro-2, 3-hexodiulo-2, 6-pyranose (10) to slightly down fields (0.7-2.6 p. p. m.) compared with the chemical shifts before oxidation. While the carbonyl groups of 1. 2-O-isopropylidene-5-O-ethyloxycarbonyl-$\alpha$-D-erythro-pentofuran-3-ulose (4) and methyl 3, 5-0-isopropylidene-$\alpha$-D-threo-pentofuranosid-2-ulose (6) pushed the $\alpha$-carbons to up fields (3, 2-18.3 p. p. m. However, the order of signals on the spectra before and after oxidation remained unaltered.

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.539-541
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• 2012

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2513-2516
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• 2008

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1723-1725
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• 2010

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2685-2690
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• 2013

The activities of Au-modified Cu electrodes toward glucose oxidation are evaluated according to their fabrication conditions and physico-chemical properties. The Au-modified Cu electrodes are fabricated by the galvanic displacement of Au on a Cu substrate and the characteristics of the Au particles are controlled by adjusting the displacement time. From the glucose oxidation tests, it is found that the Au modified Cu has superior activity to the pure Au or Cu film, which is evidenced by the negative shift in the oxidation potential and enhanced current density during the electrochemical oxidation. Though the activity of the Au nanoparticles is a contributing factor, the enhanced activity of the Au-modified Cu electrode is due to the increased oxidation number of Cu through the electron transfer from Cu to more electronegative Au. The depletion of electron in Cu facilitates the oxidation of glucose. The stability of the Au-modified Cu electrode was also studied by chronoamperometry.

• Journal of Environmental Health Sciences
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• v.23 no.1
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• pp.34-42
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• 1997

A laboratory experiments were performed to investigate the treatment of photographic processing wastewater by chemical oxidation and biological treatment system. The effect of reaction conditions such as hydrogen peroxide dosage, ferrous sulfate dosage and pH on the COD removal in Fenton oxidation were investigated. The optimal dosage of hydrogen peroxide was 2.58 M and 3.87 M for the developing and fixing process wastewater, respectively. The Fenton oxidation was most efficient in the pH range of 3-5 and the optimal condition for initial reaction pH was 5 for a developing process wastewater. With iron powder catalyst, the COD for a developing process wastewater was removed in lower pH than with ferrous sulfate catalyst. The removal efficiency of COD for refractory compounds such as Diethyleneglycol, Benzylalcohol, Hydroxylamine Sulfate, Ammonium Thiosulfate, Ammonium Ferric EDTA and Disodium EDTA in the photogaphic wastewater was found than 90% except Potassium Carbonate. When the photographic processing wastewater after pretreatment by Fenton oxidation was treated with batch activated sludge process, the addition of $KH_2PO_4$ as a phosphorous compound improved the removal efficiency of COD. During the continuous biological treatment of developing and fixing process wastewater after pretreatment by Fenton oxidation, the effluent COD concentration less than 100 mg/l was obtained at 0.425 and 0.25 kgCOD/m$^3$.d, respectively.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2019-2024
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• 2014

NiCu alloys have been suggested as potential candidates for catalysts in glucose oxidation. In this study, NiCu alloys with different compositions were prepared on a glassy carbon substrate by changing the electrodeposition potential to examine the effect of Ni/Cu ratios in alloys on catalytic activity toward glucose oxidation. Cyclic voltammetry and chronoamperometry showed that NiCu alloys had higher catalytic activity than pure Ni and Cu catalysts. Especially, Ni59Cu41 had superior catalytic activity, which was about twice that of Ni at a given oxidation potential. X-ray analyses showed that the oxidation state of Ni in NiCu alloys was increased with the content of Cu by lattice expansion. Ni components in alloys with higher oxidation state were more effective in the oxidation of glucose.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.307-314
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• 2008

폐기물 매립지의 조기 안전화를 위해 여러 가지 Chemical Oxidation법이 개발되어 왔지만, 이 방법을 폐기물 매립지에 적용하고 난 후에 생성될 수 있는 부산물들이 주변 환경에 영향을 줄 가능성이 있다. 그래서, 이 방법을 실제 매립지에 적용하기 전에, 일본 키타큐슈에 있는 소각재가 묻혀 있는 모형 매립지에 다섯 가지 조건 -A, 콤포스트 추가; B, 과산화수소수 살수; 과산화수소수+공기주입; D, 공기주입; E, control- 을 적용하여 그 효능을 테스트하였고, 이 매립지에서 이 방법들의 적용 후에 생성되는 침출수의 급성 독성을 세 가지 microbiotests를 이용하여 monitoring하였다. 테스트 기간 중, 침출수의 수질은 개선되었고, 그 급성 독성은 점차적으로 감소하였다. 과산화수소수와 공기의 조합을 적용한 후 생성된 침출수의 급성 독성이 가장 빨리 감소하여 폐기물 매립지의 조기 안정화에 도움을 주었다. 이러한 독성 시험 결과는 몇 가지 화학적 parameters와 상관성이 있었고 여기에 사용된 급성 독성 테스트법은, 매립지 안정화를 위한 Chemical Oxidation법의 적용 후, 침출수 수질을 monitoring하는데 적절하였다. 그러므로 폐기물 매립지의 조기 폐지 기준에 독성 시험의 포함을 고려해 볼 필요가 있다고 생각한다.

• Tribology and Lubricants
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• v.12 no.1
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• pp.36-41
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• 1996

The suitability of a pressure differential scanning calorimetry (PDSC) in monitoring the quality of synthetic base fluids has been investigated using polyalphaolefin (PAO) oils as an example. Induction period meassured at 170, 180 and 19$0^{\circ}C$, and 3.53 MPa oxygen pressure was applied to characterize their oxidation stability. The PDSC method has proven to be simple and repeatable and requires only small sample size for testing. More importantly, it can be applied in differentiating the oxidation performance quality of PAO oils and is versatile enough for use in studying kinetic aspects of PAO oil oxidation which include the effect of temperature and antioxidant concentration. Additionally, the method appears to correlate well with a rotary bomb oxidation test (RBOT).

• Journal of Electrochemical Science and Technology
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• v.11 no.1
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• pp.84-91
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• 2020

The PtBi/C and PtBiPd/C electrocatalysts were synthesized via the irreversible adsorption of Pd and Bi ions precursors on commercial Pt/C catalysts. XRD and XPS revealed the formation of an alloy structure among Pt, Bi, and Pd atoms. The current of direct formic acid oxidation (I_d) increased ~ 8 and 16 times for the PtBi/C and PtBiPd/C catalysts, respectively, than that of commercial Pt/C because of the electronic, geometric, and third body effects. In addition, the increased ratio between the current of direct formic acid oxidation (I_d) and the current of indirect formic acid oxidation (I_ind) for the PtBi/C and PtBiPd/C catalysts suggest that the dehydrogenation pathway is dominant with less CO formation on these catalysts.