• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.255-261
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• 2007

The catalytic behavior of the manganese oxides was studied for the selective catalytic reduction with ammonia at a low temperature condition under $200^{\circ}C$. Outlet unreacted ammonia increases with decreasing temperature and increasing $NH_3/NOx$ mole ratio, however $NO_2$ shows an opposite result. $NO_2$ is generated by the adsorption of NO on the catalyst and the following oxidization to nitrates. Unreacted NH3 slip is not observed even at the $NH_3/NOx$ feed ratio above 1.0 due to the reaction between formed nitrates on the catalyst and adsorbed ammonia. The addition of Zr increases $NO_2$ generation, whereas the addition of CeO2 on the catalyst decreases $NO_2$ generation. Furthermore, the additon of the metal oxide induce DeNOx efficiency to reduce.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.414-419
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• 2006

Effects of water vapor, hydrocarbons, and CO, which are inevitably included in exhaust gases of combustion, on a combined $De-NO_{x}$ process of non-thermal plasma and $NH_{3}$ SCR (Selective Catalytic Reduction) have been investigated. Test results showed that fast SCR reaction enhanced $De-NO_{x}$ rate under the low temperature conditions, $150{\sim}200^{\circ}C$ The present test, however, showed that the role of the fast SCR reaction can be significantly suppressed by addition of hydrocarbons in a non-thermal plasma reactor. Detailed investigation verified that such suppressed role of the fast SCR reaction could be caused by the $NO_{2}/NO_{x}$ ratio modified by aldehydes produced from hydrocarbons in a non-thermal plasma reactor. In addition, the present study was confirmed that the effects of water vapor and CO were not noticeable compared with the hydrocarbon effects.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.1
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• pp.39-47
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• 2009

Gaegurin 4(GGN 4), an antimicrobial peptide isolated from a Korean frog, is five times more potent against Gram-positive than Gram-negative bacteria, but has little hemolytic activity. To understand the mechanism of such cell selectivity, we examined GGN4-induced $K^+$ efflux from target cells, and membrane conductances in planar lipid bilayers. The $K^+$ efflux from Gram-positive M. luteus(2.5 ${\mu}g/ml$) was faster and larger than that from Gram-negative E. coli(75 ${\mu}g/ml$), while that from RBC was negligible even at higher concentration(100 ${\mu}g/ml$). GGN4 induced larger conductances in the planar bilayers which were formed with lipids extracted from Gram-positive B. subtilis than in those from E. coli(p<0.01), however, the effects of GGN4 were not selective in the bilayers formed with lipids from E. coli and red blood cells. Addition of an acidic phospholipid, phosphatidylserine to planar bilayers increased the GGN4-induced membrane conductance(p<0.05), but addition of phosphatidylcholine or cholesterol reduced it(p<0.05). Transmission electron microscopy revealed that GGN4 induced pore-like damages in M. luteus and dis-layering damages on the outer wall of E. coli. Taken together, the present results indicate that the selectivity of GGN4 toward Gram-positive over Gram-negative bacteria is due to negative surface charges, and interaction of GGN4 with outer walls. The selectivity toward bacteria over RBC is due to the presence of phosphatidylcholine and cholesterol, and the trans-bilayer lipid asymmetry in RBC. The results suggest that design of selective antimicrobial peptides should be based on the composition and topology of membrane lipids in the target cells.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.599-604
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• 2013

In this study, Ti added Mn-Cu mixed oxide catalysts were prepared by a co-precipitation method and used for the low temperature (< $200^{\circ}C$) selective catalytic reduction (SCR) of NOx with $NH_3$. Physicochemical properties of these catalysts were characterized by BET, XRD, XPS, and TPD. Mn-Cu mixed oxide catalysts were found to be amorphous with a large surface and they showed high SCR activity. Experimental results showed that the addition of $TiO_2$ to Mn-Cu oxide enhanced the SCR activity and $N_2$ selectivity. Ti addition led to the chemically adsorbed oxygen species that promoted the oxidation of NO to $NO_2$ and increased the number of $NH_3$ adsorbed-sites such as $Mn^{3+}$.

• Journal of Korean Clinical Nursing Research
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• v.24 no.1
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• pp.44-55
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• 2018

Purpose: This study aimed to explore and understand the experience of decision making among women undergoing or forgoing selective fetal reduction who have higher-order multiple pregnancies through assisted reproductive techniques. Methods: A qualitative study was conducted from August 1, to October 30, 2013. Eight participants were interviewed and the interviews were audio-recorded and transcribed verbatim. Six persons participated in in-depth interviews in person and two participated over the telephone. A thematic analysis was conducted. Results: Four themes were identified and carefully named: Confusion after higher-order multiple pregnancy; Obstacles to choice: Uncertain safety; Weighing between reality and ideality and; Influences of medical professionals. Conclusion: The results demonstrated a wide range of factors considered by women when making decisions about selective fetal reduction, and mothers' feelings of conflict and distress in the decision-making process. The results suggest that it is important for nurses to provide emotional support and consolation, in addition to sufficient information. These findings will help nurses improve their counseling techniques by understanding the situation of infertile couples.

• Journal of Information Technology Applications and Management
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• v.19 no.2
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• pp.149-179
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• 2012

This study explores the reporting tendencies of project managers when sending a status reports to their respective senior managers in information systems development project. It also examines the effect of selective reporting on report quality and systems development performance. The research model is proposed based on literature survey as well as key points from Iacovou et al. [2009] which is an extension of selective reporting in information systems project. Analysis of responses from 257 project managers in information systems industry indicates that pessimistic reporting by project managers has negative effect on both report quality (mediator variable) and systems development performance, while optimistic reporting has no significant effect on systems development performance. The CEO interest has an impact on the senior manager's power, which in turn leads to optimistic reporting by project managers. The senior manager's character has an impact on the senior manager's leadership, which in turn leads to pessimistic reporting. No direct relationship exists either between CEO interest and optimistic reporting or between senior manager's character and pessimistic reporting. In addition, trust toward the senior managers is significantly related to pessimistic reporting. Finally, report tendencies are also found to be affected by the active/passive characteristics of project managers.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.28.2-28.2
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• 2011

The selective catalytic reduction (SCR) of NOx by $NH_3$ is well known as one of the most convenient, efficient, and economical method to prevent NOx emission in flue gas from stationary sources. The degradation of the reactivity is the obstacle for its real application, since high concentrations of sulfur dioxide and thermal factor would deactivate the catalyst. It is necessary to develop high stability of catalysts for low-temperature SCR. Among the transition metal oxides, $WO_3$ is known to exhibit high SCR activity and good thermal stability. The $MnOx-WO_3-TiO_2$ catalysts prepared by sol-gel method with various $WO_3$ contents were investigated for low-temperature SCR. These catalysts were observed in terms of micro-structure and spectroscopy analyses. The $WO_3$ catalyst as a promoter is used to enhance the thermal stability of catalyst since it increases the phase transition temperature of $TiO_2$ support. It was found that the addition of tungsten oxides not only maintained the temperature window of NO conversion but also increased the acid sites of catalyst.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.821-827
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• 2010

Gene delivery that provides targeted delivery of therapeutic genes to the cells of a lesion enhances therapeutic efficacy and reduces toxic side effects. This process is especially important in cancer therapy when it is advantageous to avoid unwanted damage to healthy normal cells. Incorporating cancer-specific ligands that recognize receptors overexpressed on cancer cells can increase selective binding and uptake and, as a result, increase targeted transgene expression. In this study, we investigated whether a peptide capable of homing to hepatocellular carcinoma (HCC) could facilitate targeted gene delivery by cationic liposomes. This homing peptide (HBP) exhibited selective binding to a human hepatocarcinoma cell line, HepG2, at a concentration ranging from 5 to 5,000 nM. When conjugated to a cationic liposome, HBP substantially increased cellular internalization of plasmid DNA to increase the transgene expression in HepG2 cells. In addition, there was no significant enhancement in gene transfer detected for other human cell lines tested, including THLE-3, AD293, and MCF-7 cells. Therefore, we demonstrate that HBP provides targeted gene delivery to HCC by cationic liposomes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.848-854
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• 2015

There are a lot of encryption methods to secure database proposed recently. Those encryption methods can protect the sensitive data of users effectively, but it deteriorates the search performance of database query. In this paper, we proposed the selective element encryption method in order to complement those drawbacks. In addition, we compared the performance of the proposed method with that of tuple level encryption method using the various queries. As a result, we found that the proposed method, which use the selective element encryption with bloom filter as a index, has better performance than the other encryption method.

• Journal of Environmental Science International
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• v.13 no.6
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• pp.537-542
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• 2004

$V_{2}O_{5}/TiO_{2}$ catalysts promoted with Mn were prepared and tested for selective catalytic reduction of NOx in $NH_3.$ The effects of promoter content, degree of catalyst loading were investigated for NOx activity while changing temperatures, mole ratio, space velocity and $O_2$ concentration. Among the various $V-{2}O_{5}$ catalysts having different metal loadings, $V-{2}O_{5}$(1 wt.%) catalyst showed the highest activity(98%) under wide temperature range of $200-250^{\circ}C.$ When the $V-{2}O_{5}$ catalyst was further modified with 5 wt.% Mn as a promoter, the highest activity(90-47%) was obtained over the low temperature windows of $100-200^{\circ}C.$ From Mn-$V_{2}O_{5}/TiO_{2}$, it was found that by addition of 5 wt.% Mn on $V_{2}O_{5}/TiO_{2}$ catalyst, reduction activity of catalyst was improved, which resulted in the increase of catalytic activity and NOx reduction. According to the results, NOx removal decreased for 10%, but the reaction temperature down to $100^{\circ}C.$