• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.698-706
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• 1996

Dehydrogenation of methanol to produce formaldehyde was carried out over various silica-alumina catalysts doped with alkali metals in a continuous flow system. The reaction was rather dependent on Lewis acid than Br${\ddot{o}}$nsted acid suggesting that dehydrogenation of methanol was an electronic reaction. The Br${\ddot{o}}$nsted acid sites on silica-alumina were neutralized by doping with alkali metals, and the neutralization effect of Br${\ddot{o}}$nsted acid was dependent on the electron-donating capacity of the dopant metals. Activation energy for dehydrogenation of methanol decreased when Br${\ddot{o}}$nsted acid was neutralized by doping with K.

• Membrane Journal
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• v.6 no.4
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• pp.250-257
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• 1996

Surface crosslinked chitosan composite membranes were prepared with glutaraldehyde and surfuric acid. Effects of neutralization for complex between chitosan and acetic acid and of water permeability for substrate membranes on pervaporation performance were investigated. For ionically crosskinked membranes, effect of active layer thickness on separation factor of water/ethanol mixture was studied. With increasing the water permeability of the substrate, the membrane showed an increased separation factor, while it maintained a constant permeate flux. Neutralized chitosan composite membranes revealed a decreased separation factor and a constant permeate flux. When the thickness of the active layer increased, an optimum crosslinking time to achieve higher separation factor shifted to a prolonged times.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.57-61
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• 1992

To determin the accuracy of serological methods in detecting Borna-disease(BD) viral antibodies, 273 experimentally infected rabbit sera were compared by using indirect immunofluorescence antibody test(IFA), serum neutralization test(SN) and enzyme-linked immunosorbent assay(ELISA). One hundred twenty-three serum samples had BD viral antibodies detected by IFA. CELISA antibodies to BD virus were also present in the same one hundred twenty-three serum samples. However, neutralization test antibodies to BD virus were present in 27 of the in rabbit serum samples. Neutralization test was sensitive in comparison with KFA and CELISA. In comparison with IFA, CELISA was both sensitive and specific in detecting BD viral antibodies. These results extend observations made with laboratory animals to the diagnosis of naturally infected animals.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.12
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• pp.2731-2736
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• 2009

In this paper, a new implementation method of OFDM (orthogonal frequency division multiplexing) system with an orthogonal basis matrix is developed mathematically. The basis matrix is based on the Haar basis but has an appropriate form for modulation of multiple subchannel signals of OFDM. It is verified that the new basis matrix can be expanded with a simple recursive algorithm. The order of synthesis matrix in the transmitter is increased by the factor of two with every expansion. Demodulation in the receiver is carried out by its inverse matrix, which can be generated recursively with the orthogonal basis matrix. It is shown that perfect reconstruction of original signals is possibly achieved in the proposed OFDMsystem.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.420-420
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• 2010

AC PDP에서 유전체 보호막으로 사용되는 MgO 박막은 높은 이차전자방출계수($\gamma$)로 인해 방전전압을 낮춰주는 중요한 역할을 하고 있다. 이러한 MgO 보호막의 이차전자방출계수를 증가시키기 위해 MgO 의 Energy Band Structure 규명이 중요한 연구 주제가 되고 있다. MgO의 이차전자방출계수($\gamma$)는 Auger 중화 이론에 의해 방출 메커니즘이 설명이 되고, 그 원리는 다음과 같다. 고유의 이온화 에너지를 가진 이온이 MgO 표면에 입사 되면, Tunneling Effect에 의해 전자와 이온 사이에 중화가 일어나고, 중화가 되고 남은 에너지가 MgO Valance Band 내의 전자에게 전달되면 이때 남은 에너지(${\Delta}E$)가 MgO의 일함수(Work function) 보다 크게 되면 이차전자로 방출된다. 본 실험 에서는 $\gamma$-FIB System을 이용하여 결정 방향이 (100), (110), (111)을 갖는 Single Crystal MgO에 이온화 에너지가 24.58eV인 He Ion source를 주사 하였을 때 Auger self-convolution을 통해 이차전자의 운동 에너지 분포를 구하고, 이를 통해 MgO 내의 Energy Band Structure를 실험적으로 측정하였다. 이를 통해 MgO Single Crystal의 일함수 및 Defect Level의 분포를 확인하였다.

• The Journal of Korean Philosophical History
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• no.38
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• pp.251-273
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• 2013

This paper deals with mind and human nature dispute between Si-Ma guang and Han-Yu in the Northern Sung Dynasty, focused upon the "zhong-hua". The letter exchange between Si-Ma guang and Han-yu, which were the mind and human nature debate between a representative intellectually of the Confucianism and a scholar who absorbed in the Buddhism, can provide the discussion on various ideological origins that affected the development of the mind and human nature theory. Moreover, the contents of a letter from both of them can be used as an important cue to observe the discussion under what ideological foundations the mind and human nature theory could be embodied in the future and what advance it has made and what is its philosophical meaning.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.54-59
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• 2021

DIWS system was introduced to remove hydrogen sulfide from the biogas of wastewater treatment plant. In the case of using water into the DIWS system more than 5,000mg/L of hydrogen sulfide, 25% of H2S removal efficiency was shown and required such further treatment process as incineration which was obtained more than 98%. When the inflow of hydrogen sulfide was 5,000mg/L, CH4 and CO2 were effectively discharged and the reduction was 8.7% and 28.6%, respectively. When such neutralization chemicals as Na2CO3 and NaOH were introduced into the DIWS system, H2S was removed more than 97.2% keeping pH in the range of 11.2 to 11.5.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.391-396
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• 2005

This study was conducted to neutralize acid mine drainage (AMD) of Soo and Hambaek mines, located in Kangwon-Do Korea, using $Ca(OH)_2$. When 0.295 g $Ca(OH)_2/L$(AMD) was added to the drainage in a neutralization reactor, pH of liquid in the reactor and the effluent were maintained at 9.5 and 8.4, respectively. The pH met the required effluent standard. With 10~50% of feedback of effulent sludge to the reactor, the pH of neutralized fluid in the reactor remained nearly constant, but $SO{_4}^{-2}$ concentration in the effluent increased adversely compared to the non-return sludge case. With 30% of sludge feedback, it was possible to decrease suspended solids (SS) concentration in the effluent without a problem in Fe concentration. When 100 mL of 0.1 M $BaCl_2$ was added to 1 L of AMD treated with $Ca(OH)_2$, removal efficiency of $SO{_4}^{-2}$ increased to over 90%. Aanalyses of pH, Fe, and $SO{_4}^{-2}$ showed that the optimal results were obtained when pH of neutralizatio reactor and sludge return ratio were maintained at 9.5 and 30%. This can result in possible cost reduction of 31.4% for maintenance and 29.8% for facility construction by alternating $Ca(OH)_2$ to NaOH.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.295-301
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• 2017

Botulinum neurotoxin (BoNT/A) is a neurotoxin that selectively attacks the peripheral cholinergic nerve endings. It is produced by Gram -positive, endospore-forming strict anaerobic bacteria, Clostridium botulinum. Since BoNT/A could be a biothreat agent, as well as a contaminator of food and water supplies, the development of sensitive assays for toxin detection and potent antitoxin for the treatment of intoxication is necessary. In this study, for the purpose of producing monoclonal antibodies (mAbs) that are capable of neutralizing Botulinum neurotoxin type A (BoNT/A), scFv (single-chain variable domain fragment) libraries from the rabbit antisera against BoNT/A was fused to a human IgG. The resulting recombinant scFvIgG antibody protein was expressed in stable cell lines and was purified using a protein A affinity chromatography. The efficacy of scFvIgG mAb was confirmed by ELISA and was evaluated for the neutralization of BoNT/A in vivo. Such an in vivo toxin neutralization assay was performed using mice. Although scFvIgG antibody proteins (10 ug) failed to fully protect the mice challenged with BoNT/A (100,000 $LD_{50}$), it significantly prolonged the survival time. These results suggest that scFvIgG mAb may be capable of neutralizing BoNT/A single-chain variable domain fragment.

• Journal of the Mineralogical Society of Korea
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• v.32 no.4
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• pp.249-258
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• 2019

Acid spill accidents are frequently occurring in Korea with increasing production, use, storage, and transport of acids, accompanying industrialization and economic growth. The acids introduced to the subsurface environments would eventually be neutralized by reactions with geomedia. However, the spatial and temporal extent to which the spilled acids would affect will be dependent on the characteristics of the geomedia exposed to the acids. In this work, sulfuric acid, the most used acid in Korea, was reacted with a set of model geomedia representative of the geology of Korea. The buffering capacity of the model geomedia was determined through batch-type experiments using pH changes as an indicator. X-ray diffraction was used to identify the mineral phases contributing to the acid neutralization. The results showed that sandstone had the largest acid neutralization capacity among the tested geomedia, while kaolinite had the smallest. The findings of this study would contribute to quantitatively assessing the impact of spilled acids on geomedia and hence to predicting the vulnerability of geomedia to the spilled acid.