• 공업화학
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• 제23권1호
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• pp.105-111
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• 2012

본 연구에서는 저온에서 질소산화물 저감효율이 뛰어난 것으로 알려진 망간전구체의 종류에 따른 영향을 고찰하기 위해 초임계수열법으로 합성한 세리아($CeO_2$)와 지르코니아($ZrO_2$)를 담체로 하여 저온 SCR 공정에서의 온도에 따른 활성변화를 비교 분석하였다. Manganese acetate (MA)와 Manganese nitrate (MN), 두 종류 망간전구체의 농도를 영향인자로 고려하여 촉매의 활성변화를 고찰하였다. 활성화된 시료의 특성은 $N_2$ adsorption-desorption, TGA, XRD, XPS를 통해 분석하였고 질소산화물 저감효율을 측정하기 위해 NOx 분석기를 이용하여 De-NOx 실험을 수행하였다. 제조방법에 따라 합성한 촉매의 질소산화물 저감 효율을 분석한 결과 Manganese acetate (MA)를 활성물질로 사용한 촉매가 Manganese nitrate (MN)을 사용한 촉매에 비해 전체적인 온도 영역에서 우수한 질소산화물 저감효율을 보였다. 이는 특성분석 결과를 통해 알 수 있듯이 Manganese acetate (MA)의 주성분인 $Mn_2O_3$가 Manganese nitrate (MN)의 주성분인 $MnO_2$에 비해 높은 산소 이동도를 갖고 담체와의 강한 상호작용을 형성하는 것에 기인한 것으로 보인다.

• Journal of Microbiology and Biotechnology
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• 제18권5호
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• pp.933-941
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• 2008

An extracellular $\beta$-glucosidase produced by Monascus purpureus NRRL1992 in submerged cultivation was purified by acetone precipitation, gel filtration, and hydrophobic interaction chromatography, resulting in a purification factor of 92-fold. A $2^2$ central-composite design (CCD) was performed to find the best temperature and pH conditions for enzyme activity. Maximum activity was observed in a wide range of temperature and pH values, with optimal conditions set at $50^{\circ}C$ and pH 5.5. The $\beta$-glucosidase showed moderate thermostability, was inhibited by $HgCl_2$, $K_2Cr_O_4$, and $K_2Cr_2O_7$, whereas other reagents including $\beta$-mercaptoethanol, SDS, and EDTA showed no effect. Activity was slightly stimulated by low concentrations of ethanol and methanol. Hydrolysis of p-nitrophenyl-$\beta$-D-glucopyranoside (pNPG), cellobiose, salicin, n-octyl-$\beta$-D-glucopyranoside, and maltose indicates that the $\beta$-glucosidase has broad substrate specificity. Apparently, glucosyl residues were removed from the nonreducing end of p-nitrophenyl-$\beta$-D-cellobiose. $\beta$-Glucosidase affinity and hydrolytic efficiency were higher for pNPG, followed by maltose and cellobiose. Glucose and cellobiose competitively inhibited pNPG hydrolysis.

• 한국환경과학회지
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• 제22권1호
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• pp.73-81
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• 2013

The present work has been devoted to the catalytic reduction of $N_2O$ by $H_2$ with $Pt/SiO_2$ catalysts at very low temperatures, such as $110^{\circ}C$, and their nanoparticle sizes have been determined by using $H_2-N_2O$ titration, X-ray diffraction(XRD) and high-resolution transmission electron microscopy(HRTEM) measurements. A sample of 1.72% $Pt/SiO_2$, which had been prepared by an ion exchange method, consisted of almost atomic levels of Pt nanoparticles with 1.16 nm that are very consistent with the HRTEM measurements, while a $Pt/SiO_2$ catalyst possessing the same Pt amount via an incipient wetness technique did 13.5 nm particles as determined by the XRD measurements. These two catalysts showed a noticeable difference in the on-stream $deN_2O$ activity maintenance profiles at $110^{\circ}C$. This discrepancy was associated with the nanoparticle sizes, i.e., the $Pt/SiO_2$ catalyst with the smaller particle size was much more active for the $N_2O$ reduction. When repeated measurements of the $N_2O$ reduction with the 1.16 nm Pt catalyst at $110^{\circ}C$ were allowed, the catalyst deactivation occurred, depending somewhat on regeneration excursions.

• 공업화학
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• 제23권3호
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• pp.348-351
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• 2012

본 연구에서는 NO의 저온 SCR 반응에서 구리 첨가가 $Mn/CeO_2-ZrO_2$ 촉매의 활성에 미치는 영향을 알아보았다. 이를 위하여 $Mn/CeO_2-ZrO_2$ 촉매에 구리가 각각 5, 10, 15 wt% 첨가된 세가지 촉매의 활성을 조사하였다. 촉매의 특성은 BET, XRD, XPS, $H_2-TPR$을 통해 분석하였다. 구리가 첨가된 촉매의 질소산화물 저감 효율을 측정한 결과 Cu 농도가 증가할수록 활성이 증가하였으며 Cu 15 wt%가 담지하였을 경우 질소산화물 저감효율이 99%까지 도달하는 등 가장 높은 저감효율을 나타내었다. 이는 표면의 망간과 구리의 interaction에 의한 환원의 향상이 촉매 효율 증가의 원인으로 여겨진다.

• Parasites, Hosts and Diseases
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• 제56권1호
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• pp.11-19
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• 2018

In Brazil, visceral leishmaniasis (VL) is expanding and becoming urbanized, especially in non-endemic areas such as the State of Rio Grande do Sul. Considering that infected dogs are the main reservoir for zoonotic VL, this study evaluated the prevalence of canine visceral leishmaniasis (CVL) in the metropolitan area of Porto Alegre, a new area of expansion of VL in Brazil. Serum and plasma from 405 asymptomatic dogs from the municipalities of Canoas (n=107), $S\tilde{a}o$ Leopoldo (n=216), and Novo Hamburgo (n=82) were tested for CVL using immunochromatographic ($DPP^{(R)}$) and ELISA $EIE^{(R)}$ assays (2 assays officially adopted by the Brazilian government for the diagnosis of CVL) and real-time PCR to confirm the results. There was no agreement among serological and real-time PCR results, indicating that the Leishmania infection in asymptomatic animals with low parasite load, confirmed by negative parasitological tests (smears and parasite culture), need to be evaluated by molecular methods. The prevalence of LVC in the metropolitan region of Porto Alegre, confirmed by real-time PCR was 4% (5.6% in Canoas and 4.6% in $S\tilde{a}o$ Leopoldo). The use of molecular method is essential for accurate diagnosis of CVL, especially in asymptomatic dogs in non-endemic areas.

• BMB Reports
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• 제39권4호
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• pp.355-360
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• 2006

To gain a better understanding on the function of the potato Solanum tuberosum Multiprotein Bridging Factor 1 protein (StMBF1) its interaction with the TATA box binding protein (TBP) was demonstrated. In addition we reported that StMBF1 rescues the yeast mbf1 mutant phenotype, indicating its role as a plant co-activator. These data reinforce the hypothesis that MBF1 function is also conserved among non closely related plant species. In addition, measurement of StMBF1 protein level by Western blot using anti-StMBF1 antibodies indicated that the protein level increased upon $H_2O_2$ and heat shock treatments. However, the potato $\beta$-1,3-glucanase protein level was not changed under the same experimental conditions. These data indicate that StMBF1 participates in the cell stress response against oxidative stress allowing us to suggest that MBF1 genes from different plant groups may share similar functions.

• 한국독어학회지:독어학
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• 제3집
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• pp.327-346
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• 2001

Das Ziel dieser Arbeit liegt darin, den Bestand der wissenschaftlichen Web-Publikationen in der deutschen Linguistik darzustellen. Das Internet bietet heute $f\"{u}r$ die Forschung bereits zwei der wichtigsten produktiven $M\"{o}glichkeiten;n\"{a}mlich$ Information und Kommunikation. Akademische Kreise haben diverse Homepages entwickelt. Der schnelle Zugang zu aktuellen bibliographischen Daten und Forschungsergebnissen hat $f\"{u}r$ koreanische Germanisten einen besonders hohen Stellenwert. Wissenschaftliches Publizieren in Form von Fachzeitschriften ist ein gutes Modell $daf\"{u}r$. Fachzeitschriften erscheinen weltweit und relativ schnell, erreichen aber nur geringe Auflagen. Der Leserkreis ist fast identisch mit der Gruppe der potentiellen Autoren und Herausgeber. Ein Vorteil des elektronischen Publizierens ist die M\"{o}glichkeit$ multimeiale Dokumente und $weiterf\"{u}hrende$ Hyperlinks zu integrieren. Aber die $Qualit\"{a}t\;der\;Aufs\"{a}tze$ kann man kaum objektiv ermitteln und nur schwer beurteilen. Elektronische Zeitschriften $k\"{o}nnen$ sich in der Wissenschaft nur dann etablieren, wenn es gelingt, als wissenschaftliche Arbeiten von den wissenschaftlichen Kreisen oder von der Univerwaltung anerkannt zu werden. Folgende on-line wissenschaftliche Fachzeitschriften werden hier dargestellt; Linguistik online(ISSN 1615-3014), The Web Journal of Modern Language Linguistics(ISSN 1461-4499), PhiN(ISSN 1433-7177), Zeitschrift $f\"{u}r$ interkulturellen Fremdsprachenunterricht(ISSN: 1205-6545), und Language Learning & Technology(ISSN 1094-3501). 1)http://viadrina.euv-frankfurt-o.de/$\~wjoumal/deutsch/$ 2)http://wjmll.ncl.ac.uk/ 3)http://www.fu-berlin.de/phin/ 4)http://www.ualberta.ca/$\~german/ejoumal/$ 5)http://llt.msu.edu/ In der folgenden Homepage kann man auch eine Quellensammlung zu 'Dissertationen Online' finden. 6) http://www.educat.hu-berlin.de/$diss\_online/biblio.html$ Eine individuelle und institutionelle Offenheit und eine $n\"{u}chteme$ Anwendung der Materialien sind bei der Herstellung und Nutzung von Forschungsergebnissen erforderlich.

• 한국자동차공학회논문집
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• 제20권1호
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• pp.20-27
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• 2012

The $NH_3$-SCR characteristics of $NO_X$ over a V-based catalyst are experimentally examined over a wide range of operating conditions, i.e., $170-590^{\circ}C$ and $30,000-50,000h^{-1}$, with a simulated diesel exhaust containing $NH_3$, NO, $NO_2$, $O_2$, $H_2O$, and $N_2$. The influences of the space velocity and oxygen concentration on the standard-SCR reaction are analyzed, and it is shown that the low space velocity and high oxygen concentration promote the SCR activity by ammonia. The best $deNO_X$ efficiency is obtained with a $NO_2/NO_X$ ratio of 0.5 because of an enhanced chemical activity induced by the fast-SCR reaction, while at the $NO_2/NO_X$ ratios above 0.5 the $deNO_x$ activity decreases due to the slow-SCR reaction. The oxidation of ammonia begins to take place at about $300^{\circ}C$ and the reaction products, such as $N_2$, NO, $NO_2$, $N_2O$, and $H_2O$, are produced by the undesirable oxidation reactions of ammonia, particularly at high temperatures above $450^{\circ}C$. Also, $NO_2$ decomposes to NO and $O_2$ at temperatures above $240^{\circ}C$. Therefore, $NO_2$ decomposition and ammonia oxidation reactions deteriorate significantly the SCR catalytic activity at high temperatures.

• Asian-Australasian Journal of Animal Sciences
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• 제22권8호
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• pp.1140-1150
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• 2009

Forage diets provide good quality carcasses in sheep but very little is known in tropical goats. An experiment was designed with Creole male goats using grass-based systems to assess carcass yield, scores, cuts and composition. After weaning (84 d, 9.2 kg LW) two modes of forage feeding were compared with two replicates of each. Feeding groups were: PF for animals reared at pasture (n = 62) and IF when reared indoors (n = 60). Given that forage finishing will result in low ADG it appeared necessary to study different fattening lengths. The kids were equally divided into 4 groups: group A (n = 32), 4mo after weaning; group B (n = 32), 4mo after A; group C (n = 30), 3mo after B and group D (n = 28), 2mo after C. The animals grazed (in two sub-flocks) on irrigated tropical pastures managed in a rotational system (28 d of re-growth) at a mean stocking rate of 1,200 kg/ha/yr LW. The IF groups were reared in collective pens on a slatted floor (2 replicates of 7 or 8 kids each). They were fed the same stand of tropical grass (25% DM, 12% CP) as that of pasture that was cut daily and provided ad libitum. The ADG (-10%), the weights of omental fat (-60%) and fat in shoulder (-18%), the ultimate pH of carcass (-12%), the meat colour score (-24%), the ""parameter accounting for redness (12%) and the DM and lipid contents (-4%) were significantly lower (p<0.05) in PF than in IF, while the liver was heavier (+23%, p<0.05). Feeding conditions seemed to be similar, thus, differences could be related to gastrointestinal parasitism in the PF system and hypotheses are discussed. Increasing the fattening duration, resulted in significant difference (p<0.01) in many traits: the weights at slaughter and of carcass increased by 40% and 60% from groups A to D and consequently the weights of body compartments and carcass cuts (1.5 to 2.0 fold more). When the results were presented as percentage of empty body weight and carcass weight, these preliminary results (carcass weight 9kg and yield 53%, muscle proportion 70%) and qualitative parameters (low fat score 2/5, fat proportion 5%), seem to be a good incentive for the sector to develop a niche market to meet consumer lean meat expectations. The indoors system could be implemented where there was low availability of grazing areas or problems of dog attacks.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(2)
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• pp.818-823
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• 1995

방사성 폐기물 소각로에서 발생하는 off-gas중에는 NOx가 포함되어 있으며 이를 제어하기 위하여 NOx 배출의 재어에 효과적이라고 알려진 SCR법을 사용하여 실험을 행하였다. NOx 방출 저감화를 위해 상업화된 다양한 촉매들 중에서 V$_2$O$_{5}$, MoO$_3$ Fe$_2$O$_3$ 그리고 SnO$_2$를 TiO$_2$honeycomb형태의 담체에 담지시켜 제조한 촉매들의 특성을 조사하고 여러 변수들, 예를 들면 촉매의 종류, 담체의 종류, 반응온도, feed의 조성 등이 반응특성에 미치는 영향을 실험실 규모의 반응기에서 조사하였다. 10%V$_2$O$_{5}$TiO$_2$촉매가 35$0^{\circ}C$에서 94.4%의 높은 NO-$N_2$전환율을 보였으며 열적 안정성이 높은 SnO$_2$나 MoO$_3$의 첨가는 높은 전환율을 보이는 온도 범위를 확장시켜 주었다.