• 분석과학
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• 제13권3호
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• pp.315-322
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• 2000

시금치의 뿌리 조직과 ferrocene을 탄소반죽 전극에 고정하여 과산화수소를 정량할 수 있는 전극을 만들었다. Ag/AgCl 전극에 대하여 -0.3~0.0V의 전위의 범위에서 전극의 감도를 관찰하였으며 전극의 감응시간은 11.8sec로 나타났다. 전극의 검출한계는 $2.25{\times}10^{-6}M$ 이었으며, $1.0{\times}10^{-3}M$ 과산화수소를 이용해 15회 반복 측정한 결과, 상대표준편차는 1.87% 이었다. 효소전극의 감도는 19일 사용 후 40%로 감소하였다.

• International Journal of Aeronautical and Space Sciences
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• 제18권2호
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• pp.270-278
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• 2017

This paper describes development procedure and verification test results of a bi-propellant thruster using hydrogen peroxide and kerosene. The design thrust of the thruster is about 500 N and six swirl type coaxial injectors were used. The passage type manifolds were employed for the injector head to reduce the response time. The passage was designed to minimize stagnation points and recirculation region to ensure uniform flow distribution and sufficient cooling performance through flow analysis using Fluent. A catalytic igniter using hydrogen peroxide was installed at the center of the injector head. The propellant feeding and spray characteristics were confirmed by hydraulic tests. Combustion tests were performed on design and off-design points to analyze combustion characteristics under various mixture ratio conditions. The combustion test results show that combustion efficiency was over 95 % and chamber pressure fluctuation were less than 1.5 % under all test conditions.

• 자원리싸이클링
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• 제10권2호
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• pp.20-26
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• 2001

석유화학 폐촉매의 유가금속을 회수하기 위하여 과산화수소를 환원제로 사용하여 코발트, 망간, 철의 황산침출거동을 조사하였다. 유가금속의 침출은 반응시작 30분 이내에 모두 이루어졌으며, 고액농도 10 g/L, 0.5N $H_2$$SO_4$, $25^{\circ}C$, 30분 300 rpm에서 과산화수소를 0.027mol/L 첨가한 경우가 첨가하지 않은 경우에 비해 망간, 코발트, 철의 침출율이 24.9%, 20.6%, 30.1온에서 93.0%, 87.0%, 100%로 각각 향상되었다 황산농도가 0.5N H2s04까지 증가함에 따라 각 금속들의 침출율은 증가하였으며, 그 이상의 농도에서는 일정한 침출율을 나타내었다 한편, 반응온도가 증가할수록 망간, 코발트, 철의 침출율이 감소하는 경향을 보였다

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 제33회 추계학술대회논문집
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• pp.74-77
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• 2009

본 연구에서는 과산화수소/케로신 촉매 점화기의 최적 설계를 위하여 점화기 설계와 운용 조건에 따른 점화 특성을 확인하였다. 그 결과 촉매대의 출구 면적은 분해된 가스가 쵸킹이 발생하지 않도록 충분하여야 하며, 케로신은 촉매대 중앙에서 미립화가 잘되도록 분무하여야 함을 확인하였다. 또한 점화기를 운용하는데 있어 예열이 없을 경우 과산화수소를 약 3초 정도 리드해야 하며, 퍼지는 케로신 공급과 같거나 늦게 공급하는 것이 바람직함을 확인하였다.

• 생약학회지
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• 제27권2호
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• pp.101-104
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• 1996

Hydrogen peroxide is one of major chemicals mediating antitumor and antimicrobial activities of macrophages. We searched natural products enhancing hydrogen peroxide generation from murine macrophage-like cell line J774. Among 21 methanol extracts of Korean medicinal plants, the extract from Cornus officinalis was the most effective. The active component from the fractions was searched by activity guided fractionation, and identified as ursolic acid by spectral data.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 1998년도 가을 학술발표회 프로그램
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• pp.1-1
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• 1998

Advanced (Chemical) oxidation processes (AOP) differ from most conventional ones in that hydroxyl radical(OH.) is considered to be the primary oxidant. Hydroxyl radicalcan react non-selectively with a great number of organic and inorganic chemicals. The typical rate constants of true hydroxyl radical reactions are in the range of between 109 to 1012 sec-1. Many processes are possible to generate hydroxyl radical. These include physical and chemical methods and their combinations. Physical means involves the use of high energy radiation such as gamma ray, electron beam, and acoustic wave. Under an applied high energy radiation, water molecules can be decomposed to yield hydroxyl radicals or aqueous electrons. Chemical means include the use of conventional oxidants such as hydrogen peroxide and ozone, two of the most efficient oxidants in the presence of promoter or catalyst. Hydrogen peroxide in the presence of a catalyst such as divalent iron ions can readily produce hydroxyl radicals. Ozone in the presence of specific chemical species such as OH- or hydrogen peroxide, can also generate hydroxyl radicals. Finally the combination of chemical and physical means can also yield hydroxyl radicals. Hydrogen peroxide in the presence of acoustic wave or ultra violet beam can generate hydroxyl radicals. The principles for hydroxyl radical generation will be discussed. Recent case studied of AOP for water treatment and other environmental of applications will be presented. These include the treatment of contaminated soils using electro-Fenton, lechate treatment with conventional Ponton, treatment of coal for sulfur removal using sonochemical and the treatment of groundwater with enhanced sonochemical processes.

• BMB Reports
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• 제46권12호
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• pp.600-605
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• 2013

Interplay between calcium ions ($Ca^{2+}$) and reactive oxygen species (ROS) delicately controls diverse pathophysiological functions of vascular smooth muscle cells (VSMCs). However, details of the $Ca^{2+}$ and ROS signaling network have been hindered by the absence of a method for dual measurement of $Ca^{2+}$ and ROS. Here, a real-time monitoring system for $Ca^{2+}$ and ROS was established using a genetically encoded hydrogen peroxide indicator, HyPer, and a ratiometric $Ca^{2+}$ indicator, fura-2. For the simultaneous detection of fura-2 and HyPer signals, 540 nm emission filter and 500 nm~ dichroic beamsplitter were combined with conventional exciters. The wide excitation spectrum of HyPer resulted in marginal cross-contamination with fura-2 signal. However, physiological $Ca^{2+}$ transient and hydrogen peroxide were practically measurable in HyPer-expressing, fura-2-loaded VSMCs. Indeed, distinct $Ca^{2+}$ and ROS signals could be successfully detected in serotonin-stimulated VSMCs. The system established in this study is applicable to studies of crosstalk between $Ca^{2+}$ and ROS.

• Applied Biological Chemistry
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• 제33권2호
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• pp.129-132
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• 1990

저온에서 식물체중에 축적되는 과산화수소의 생리적 기능을 IAA수준의 조절과 관련하여 연구하였다. 과산화수소는 10mM농도에서 완두의 발근과 귀리 초엽의 신장을 억제하였으며 IAA의 호르몬 효과도 억제하였다. 이 억제효과는 catalase를 첨가하면 해제되었다. 유리의 IAA는 과산화수소와 반응하여 Salkowski시약에 민감하지 않은 어떤 복합체를 형성하여 과산화수소에 의하여 불활성화되는 것처럼 보였다. 그러므로 저온에서 식물체내에 축적된 과산화수소는 IAA를 불활성화하여 세포의 유용한 IAA수준을 하향조절하였을 것으로 여겨졌다.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3668-3674
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• 2010

Mesoporous SBA-15 was synthesized using tetraethylorthosilicate (TEOS) as the silica source and Pluronic (P123) as the structure-directing agent. The defective Si-OH groups present in SBA-15 were successively grafted with 3-chloropropyltrimethoxysilane (CPTMS) followed by tris-(2-aminoethyl) amine (TAEA) and/or tetraethylenepentamine (TEPA) for effective immobilization of silver nanoparticles. Grafting of TAEA and/or TEPA amine and immobilization of silver nanoparticles inside the channels of SBA-15 was verified by XRD, TEM, IR and BET techniques. The silver nanoparticles immobilized on TAEA and /or TEPA grafted SBA-15 was subjected for electrocatalytic reduction of hydrogen peroxide ($H_2O_2$). The TEPA stabilized silver nanoparticles show higher efficiency for reduction of $H_2O_2$ than that of TAEA, due to higher number of secondary amine groups present in TEPA. The amperometric analysis indicated that both the Ag/SBA-15/TAEA and Ag/SBA-15/TEPA modified electrodes required lower over-potential and hence possess high sensitivity towards the detection of $H_2O_2$. The reduction peak currents were linearly related to hydrogen peroxide concentration in the range between $3{\times}10^{-4}\;M$ and $2.5{\times}10^{-3}\;M$ with correlation coefficient of 0.997 and detection limit was $3{\times}10^{-4}\;M$.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.120-127
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• 2017

로켓 등급의 고농도 과산화수소는 촉매 분해를 통해 높은 온도의 산소와 수증기를 발생하며, 이와 같은 성질을 이용하여 우주 추진 기술로 사용된 바 있다. 본 연구에서는 과산화수소의 촉매 분해를 이용한 수중 추진 시스템 관련 문헌 조사 및 개념 설계를 진행했다. 과산화수소 분해 가스를 분사하는 분사기 설계의 경우 로켓 노즐 설계 방식과 유사하게 진행했으며, 두 종류의 형태로 엔진 설계를 진행했다. 환형의 형태의 가스 분사기를 갖는 엔진을 제작하여 수중 환경에서 작동 시험을 수행했으며, 엔진 노즐 출구의 면적에 따른 성능 변화를 관찰했다. 향후 중앙에서 가스를 분사하는 방식의 엔진을 제작하여 성능 평가를 수행할 예정이다.