• 한국가스학회지
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• 제19권6호
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• pp.105-109
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• 2015

본 연구는 해상 유류오염사고가 발생한 경우 효율적인 방재 작업을 수행하기 위하여 개발된 오일 회수장치로서, 오일 회수장치를 통하여 해상에 유출된 기름을 높은 회수율로 신속하게 처리하는 것을 목표로 한다. 오일 회수장치는 기존의 흡착포 및 유류처리제를 이용한 정화 방식에서 발생하는 2차 오염을 방지할 수 있으며 오일 회수율 또한 우수한 특징을 가진다. 또한 유증기에 의한 폭발 방지 기구를 채택하여 오일 회수 작업시 발생할 수 있는 위험 요소를 제거 하였다.

• Bulletin of the Korean Chemical Society
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• 제22권7호
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• pp.685-688
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• 2001

A gas chromatography/mass spectrometric assay method has been developed for the simultaneous determination of benzidine (BZ), N-acetyl benzidine (ABZ) and N,N-diacetyl benzidine (DABZ) in rat urine. BZ, ABZ and DABZ were extracted from urine at pH 8 with ethyl ether. Conjugated urinary metabolites were extracted at pH 8 after hydrolysis with 1 M HCl for 30 min at 100 $^{\circ}C.$ The dried extract was dissolved in 100 ${\mu}{\ell}$ of ethylacetate and then injected in gas chromatography-mass spectrometric (GC-MS) system without further purification or modification. BZ, ABZ and DABZ have good chromatographic properties and offer very sensitive response for the EI-MS (SIM) without any derivatization. The recoveries for BZ, ABZ and DABZ were about 98.0, 81.8 and 71.4%, respectively, at pH 8.0 and the concentration of 5.0 ng/mL. The coefficients of variation of BZ and ABZ were less than 9.5% from 0.1 to 100 ng/mL and that of DABZ was less than 13% in the same concentration range. The detection limits of the assay were 0.01 ng/mL for both BZ and ABZ, and 0.05 ng/mL for DABZ in urine or plasma 1.0 mL.

• 대한금속재료학회지
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• 제48권5호
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• pp.424-429
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• 2010

In the RH process, it is possible to obtain quicker processing times by enhancing the decarburization rates at a low carbon range of steel melt through Ar gas injection into the vacuum vessel. The RH decarburization reaction was simulated through a dissolved oxygen removal reaction by injecting nitrogen into a 1/8 scale RH water model system. The gas nozzles for the N$_{2}$ injection into the vacuum vessel were located at the lowest level of the vessel's outer wall. The nitrogen bubbling in the vacuum vessel resulted in an increase in the reaction rate constant, which rose in accordance with an increase in the bubbling flow rate and number of nozzles used. However, there was almost no variation in the reaction rate constant, which depended on the horizontal positions of the bubbling nozzles.

• Korean Membrane Journal
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• 제1권1호
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• pp.1-7
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• 1999

Pd-ceramic composite membranes and catalytic membrane reactors(CMR) have been studied for hydrogen and its isotopes (deuterium and tritium) purification and recovery in the fusion reactor fuel cycle. Particularly a closed-loop process has been studied for recovering tritium from tritiated water by means of a CMR in which the water gas shift reaction takes place. The development of the techniques for coating micro-porous ceramic tubes with Pd and Pd/Ag thin layers is described : P composite membranes have been produced by electroless deposition (Pd/Ag film of 10-20 $\mu$m) and rolling of thin metal sheets (Pd and Pd/Ag membranes of 50-70 $\mu$m). Experimental results of the electroless membranes have shown a not complete hydrogen selectivity because of the presence of some defects(micro-holes) in the metallic thin layer. Conversely the rolled thin Pd and Pd/ag membranes have separated hydrogen from the other gases with a complete selectivity giving rise to a slightly larger (about a factor 1.7) mass transfer resistance with respect to the electroless membranes. Experimental tests have confirmed the good performances of the rolled membranes in terms of chemical stability over several weeks of operation. Therefore these rolled membranes and CMR are adequate for applications in the fusion reactor fuel cycle as well as in the industrial processes where high pure hydrogen is required (i.e. hydrocarbon reforming for fuel cell)

• 청정기술
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• 제17권4호
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• pp.389-394
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• 2011

바이오가스로부터 이산화탄소와 질소를 제거하기 위한 흡착공정은 많이 논의되고 있다. 특히 흡착공정 중에서 압력변동흡착(Pressure swing adsorption)공정은 에너지소모가 적고 가격이 경제적이기 때문에 기체의 분리와 정제를 위한 공정으로 적절하다. 물리적 흡착을 사용하는 PSA공정은 흡착과 탈착이 가능하다. 각 cycle단계의 구성은 가압, 주입 및 흡착, 압력 균등화, 감압 및 세정으로 이루어져있다. 본 실험에서 PSA공정은 이산화탄소와 질소를 제거하기 위한 흡착제로 zeolite 13X와 carbon molecular sieve (CMS)로 구성되어 있으며, 혼합 가스의 농도는 $CH_4/CO_2/N_2$ (75:21:4 vol%)의 비율을 갖고 있다. 각각 zeolite 13X와 CMS는 선택적으로 혼합가스로부터 질소와 이산화탄소를 흡착하여 분리하고 제거한다. 또한 CMS의 경우는 빠르게 분산되는 이산화탄소의 처리량이 높다. 상부탱크, 하부탱크, 주입탱크의 가스 조성은 TCD 검출기를 이용하는 gas chromatography (GC)에 의해서 측정되었다.

• Journal of Advanced Marine Engineering and Technology
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• 제29권5호
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• pp.488-494
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• 2005

The ejector is used to obtain a vacuum state, and it has been applied to a lot of industry field such as a heat engine, a fluid instrument power plant. a food industry, an environment industry etc., because there is no problem even it is mixed with any kind of liquid, gas. and solid. The flow characteristics in the ejector was investigated by a PIV and a CFD. The agreement between numerical analysis and experiment shows the validity of this study and the results of this study would be useful to the engineers who design for the flow systems for heating. ventilation. air conditioning and wastewater purification plants.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2005년도 수소연료전지공동심포지움 2005논문집
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• pp.373-378
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• 2005

[ $Zn(BH_4)_2$ ] ($8.4\;wt\%$ theoretical hydrogen storage capacity) powders have been successfully synthesized by mechanochemical reaction from mixtures of $ZnCl_2$ and $NaBH_4$ powders in a 1:2 molar ratio in different times. $$ZnCl_2\;+\;2NaBH_4\rightarrow\;Zn(BH_4)_2\;+\;2NaCl\;(1)$$ $Zn(BH_4)_2$ powders were characterized by X-ray diffractometry(XRD), and Furier Transform Infrared spectrometry(FT-IR). The thermal stabilities of $Zn(BH_4)_2$ powders were studied by Differential scanning calorimetry(DSC), Thermogravimetry analysis(TGA), and Mass spectrometry(MS). $Zn(BH_4)_2$ can be tested for hydrogen evolution without further purification. The reaction to yield hydrogen is irreversible, the other products being compounds of Zn, and borane. $Zn(BH_4)_2$ thermally decomposes to release borane and hydrogen gas between about 85 and $150^{\circ}C$.

• 한국수소및신에너지학회논문집
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• 제25권6호
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• pp.602-608
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• 2014

The sequence of bond overlap population of metal hydrogen binding is in Al-H > Fe-H > Zr-H > V-H. This results shows the binding energy of Al-H is the biggest in this metals (Al, Fe, Zr, and V) and hydrogen interaction. The Vanadium-hydrogen binding shows the weakest binding energy compared to other metals and it causes easy hydrogen desorption from the corresponding metals. The net charge of Al-H show the biggest value of 0.2248 and the severe localizations of electrons around aluminum and imply strongest covalent binding nature in these metals. This study is applicable to the purification of hydrogen in other bulk gas.

• 한국대기환경학회지
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• 제19권1호
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• pp.101-112
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• 2003

Biological methods are frequently used for treatment of contaminated air, containing volatile organic compounds and odor compounds in low concentrations and high flow rate of air streams. For more than 20 years. biofilter has been recognized as a cost effective technology for the purification of contaminated air. Most commercial applications before 1990 were for control of odors. In the past decades major progress has been accomplished in the development of vapor phase bioreactor. in particular biotrickling filers. Biotrickling filters are more complex than biofilters. but are usually more effective, especially for the treatment of compounds which are difficult to degrade or compounds that generate acidic by-products. While the level of understanding of biotrickling filtration process for VOCs still remains limited. the evidence success of biotreatment of VOC in air resulted in pursuing active research. This paper presents fundamental and practical aspert of VOCs treatment from air in biotrickling filter. Special emphasis is given to the operating parameters and the factors influencing performance for biotrickling filter.

• 한국태양에너지학회 논문집
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• 제21권2호
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• pp.55-67
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• 2001

This study contains the photocatalytic degradation of methyl-tert-butyl ether(MTBE), one of water-contaminating substances, into $CO_2$. Herein was investigated factors, kinetics, and reaction pathways related with MTBE degradation. This works is possible to be applied in the field of environmental remediation such as undergroundwater purification with optimized system configuration in the near future.