• 제목/요약/키워드: Aerobic oxidation

검색결과 190건 처리시간 0.025초

Preparation of Ruthenium Incorporated Heterogeneous Catalysts Using Hydroxyapatite as Catalytic Supports for Aerobic Oxidation of Alcohols

  • Kim, Sohee;Jung, Jong-Hwa;Kim, Dong-Hee;Woo, Dong Kyun;Park, Joon B.;Choi, Myong Yong;Kwon, Ki-Young
    • Bulletin of the Korean Chemical Society
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    • 제34권1호
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    • pp.221-224
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    • 2013
  • Three different kinds of hydroxyapatites (HAPs) having different sizes and compositions are prepared by hydrothermal and molten salt syntheses. Using the ion exchange reactions, ruthenium ions are incorporated on the surface of HAPs. The crystallinity, morphology and ruthenium contents are investigated by XRD, SEM, TEM and ICP. We found that smaller size of HAP having large amounts of ruthenium under ion exchange reaction shows higher catalytic activity for aerobic oxidation of alcohols.

Facile One-Pot Synthesis of 1,3,5-Trisubstituted Pyrazoles from α,β-Enones

  • Yu, Jin;Kim, Ko Hoon;Moon, Hye Ran;Kim, Jae Nyoung
    • Bulletin of the Korean Chemical Society
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    • 제35권6호
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    • pp.1692-1696
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    • 2014
  • A practical and efficient one-pot synthesis of 1,3,5-trisubstituted pyrazoles from ${\alpha},{\beta}$-enones and arylhydrazine hydrochlorides has been developed. The pyrazoles were formed via a tandem formation of the corresponding pyrazolines and an acid-catalyzed aerobic oxidation process.

An Efficient and Mild Oxidation of α-Isophorone to Ketoisophorone Catalyzed by N-Hydroxyphthalimide and Copper Chloride

  • Chen, Lihua;Tang, Ruiren;Li, Zhongying;Liang, Shan
    • Bulletin of the Korean Chemical Society
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    • 제33권2호
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    • pp.459-463
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    • 2012
  • N-hydroxyphthalimide (NHPI) and copper chloride ($CuCl_2$) were first utilized for aerobic oxidation of ${\alpha}$-isophorone (${\alpha}$-IP) to ketoisophorone (KIP) and the effects of co-catalysts, temperature, reaction time, solvent, amount of $CuCl_2$ and pressure of oxygen were investigated extensively. NHPI/$CuCl_2$ turned out to be highly efficient to this oxidation with up to 91.3% conversion and 81.0% selectivity under mild conditions. And various hydrocarbons including benzylic compounds, cycloalkene and its derivatives were also oxidized smoothly under optimized conditions. Moreover, the possible reaction mechanism was proposed and verified by FT-IR spectra.

호기성 벤질 알코올 산화반응을 위한 팔라듐 이산화티타늄 촉매 개발 (Synthesis of Pd/TiO2 Catalyst for Aerobic Benzyl Alcohol Oxidation)

  • 조태준;유계상
    • 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.

Packaging Effect on Microbial and Physicochemical Changes in Irradiated Cooked Pork Sausage during Frozen Storage at $-21^{\circ}C$

  • Cheorun Jo;Son, Jun-Ho;Kim, Jae-Hyun;Cho, Kyoung-Whan;Byun, Myung-Woo
    • Preventive Nutrition and Food Science
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    • 제6권4호
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    • pp.211-215
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    • 2001
  • The packaging effect on physicochemical changes in irradiated sausage stored at -2$0^{\circ}C$ was studied. Emulsion-type cooked pork sausage was made with (156 ppm) or without NaNO$_2$ (0 ppm), and packaged in three different conditions such as aerobic, vacuum and $CO_2$ (100%). The samples irradiated at 0, 5 and 10 kGy absorbed dose, and the total number of microorganisms, lipid oxidation, color and texture were analyzed during frozen storage at-2$0^{\circ}C$. Irradiation of the sausage at 10 kGy completely controlled microbial growth during storage. An NaNO$_2$ addition to the sausage significantly reduced lipid oxidation, and the TBARS value of the sausage with aerobic packaging was higher than that with the vacuum and $CO_2$ packaging. The NaNO$_2$ addition increased Hunter color a-value dramatically, but no packaging effect was found (p > 0.05). Irradiation influenced shear values resulting in lower shear values in 10 kGy-irradiated sausages with aerobic packaging, and $CO_2$ packaged sausage showed comparatively lower shear value than other packaging methods. From the results, vacuum or $CO_2$ (100%) packaging were better than aerobic packaging for frozen stored pork sausage, especially far microbial quality and lipid oxidation.

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포장방법에 따른 양념갈비의 저장 중 총균수, 전자공여능 및 지방산화의 감마선 조사효과 (Effect of Gamma Irradiation on Microbial Growth, Electron Donating Ability, and Lipid Oxidation of Marinated Beef Rib (Galbi) with Different Packaging Methods)

  • 강호진;조철훈;이나영;김정옥;변명우
    • 한국식품영양과학회지
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    • 제33권5호
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    • pp.888-893
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    • 2004
  • 양념갈비의 품질 안정성 및 저장성 확보를 위한 일환으로 시판되는 양념갈비에 감마선 조사(0, 2.5, 5, 7.5 kGy)하여 포장 방법(함기 vs 진공) 및 저장 기간에 따른 양념갈비의 총균수, pH, 수분활성도, 전자공여능 및 지방산패도를 측정하였다. 감마선 조사한 양념갈비의 미생물 생육은 조사선량이 증가할수록 저하되었고 포장방법별로는 함기포장구보다 진공포장구가 미생물 생장억제에 더욱 효과적임을 확인하였다. pH는 함기포장구에서 저장 7일째 다소 감소하는 경향을 보였으나 포장방법과 조사선량에 따른 유의 차가 나타나지 않았다. 감마선 조사한 양념갈비의 전자공여능은 저장기간에 따라 감소하는 경향을 보였으나 그 감소폭은 함기포장구가 진공포장구보다 크게 나타났다. TBARS값은 진공포장구의 경우 감마선 조사선량과 저장기 간에 따라 유의적인 차이는 없었다. 그러나 함기포장구는 조사선량이 증가할수록 그리고 저장기간에 따라 유의적으로 증가하여 저장 7일째 진공포장구보다 2배의 높은 값을 나타내었다. 따라서 시판되는 양념갈비의 저장 중 유통안전성을 확보하기 위한 감마선 조사의 사용에서 품질을 유지하기 위해서는 진공포장으로 유통하는 것이 바람직하다고 판단된다.

생물학적 질소 제거공정에서 ORP 측정을 통한 외부탄소원의 자동 주입 제어 (Automatic Addition Control of the External Carbon Source by the Measurement of ORP in Biological Nitrogen Removal Process)

  • 신춘환
    • 한국환경과학회지
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    • 제21권3호
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    • pp.383-390
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    • 2012
  • For the cost-effective biological nitrogen removal (BNR) process whose characteristics of influent have low COD/N ratios, the automatic control system for the addition of external carbon based on oxidation-reduction potential (ORP) data in an anoxic reactor has been developed. In this study, it was carried out with a pilot-scale Bardenpho process which was consisted of anoxic 1, aerobic 1, aerobic 2, anoxic 2, aerobic 3 tank and clarifier. Firstly, the correlation coefficient ($R^2$) of the dosage of external carbon source and ORP value was about 0.97. Consequently, the automatic control system using ORP showed that the dosage of external carbon source was decreased by about 20% compared with a stable dosage of 75 mg/L based on the COD/N ratio of the anoxic influent.

혐기소화액의 고온호기산화 공정 적용에 관한 연구 (Application of the Thermophilic Aerobic Oxidation (TAO) System to Anaerobic Digestate Stabilization in Korea)

  • 김수량;김하제;조슈아 나이젤 할더;이지혜;신명철;김태하;이명규
    • 한국축산시설환경학회지
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    • 제21권1호
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    • pp.21-28
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    • 2015
  • We studied the possibility on the application of the Thermophilic Aerobic Oxidation (TAO) process to anaerobic digestate stabilization. In treating digestate with TAO reactor the internal temperature of the reactor was increasing higher and $51^{\circ}C$ and over was maintained after 6 days on. The physiochemical compositions of liquids increased from pH 8.1 to 9.8 and EC decreased from 29.8 to 12.0 mS/cm in treating process of digestate with TAO reactor. CODcr decreased from 22,654 to 18,843 mg/L, showed about 16.82% of remove efficiency. TN and $NH_4-N$ decreased from 4,813 to 1,733 mg/L, from 3,815 to 812 mg/L respectively, which showed about 64.0% and 78.7% of removal efficiency respectively.