• 한국식품저장유통학회지
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• 제19권2호
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• pp.308-314
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• 2012

발암성 ethyl carbamate의 전구물질인 요소의 분해를 촉매하는 urease 생산 효모를 분리하고 그 특성을 조사하였다. 우리나라 전통 누룩으로부터 약 223주의 효모를 분리하고 이들 중 urease 활성이 있는 6 균주를 선별하였다. 분리된 6 균주는 ITS I-5.8S-ITS II 영역의 PCR-RFLP 분석 및 계통분석을 통하여 이 균주 모두가 $I.$ $orientalis$ ATCC 24210과 99.8% 이상의 염기서열 상동성을 나타내어 유전적으로 매우 가까운 근연관계에 있음을 확인하였다. 분리 효모 중 uresae 활성이 가장 강한 2 균주 JJ22와 SH10을 선정하여 형태학적, 생리학적 특성을 조사한 결과 $I.$ $orientalis$와 특성이 거의 유사하여 $I.$ $orientalis$로 동정하였다. 이 균주들은 온도 $20-40^{\circ}C$의 넓은 범위에서 생육이 양호하였으며 JJ22의 경우에는 $35^{\circ}C$, SH10의 경우에는 $30^{\circ}C$에서 urease 활성이 가장 높았다. pH의 영향을 조사한 결과 pH 2.0-6.0까지 넓은 범위의 산성 조건에서 생육이 매우 양호하여 호산성 효모로 생각된다. Urease 효소의 활성은 PH 5.0에서 최대치를 나타내었고 pH가 감소하거나 높아짐에 따라 활성이 감소하였다.

• 한국환경농학회지
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• 제13권2호
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• pp.151-159
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• 1994

본 연구는 음용수로 사용하고 있는 지하수를 대상으로 양돈시설이 밀집해 있는 서북부지역의 19개 관정과 동북부지역의 9개 관정의 지하수를 채취하여 지역간 $NO_3-N$ 농도의 차이, $NO_3-N$과 다른 이온과의 관계, 각 이온간의 관계 및 이온조성의 차이를 밝히기 위하여 수행되었다. 서북부 지역에서 양돈단지 주변의 D-41과 D-202 관정의 $NO_3-N$ 농도는 10.95 및 13.1mg/l로서 음용수 수질 기준을 초과하였으며, D-65, D-35 및 D-120 관정에서의 농도는 음용수 수질기준에 비하여 약간 낮았다. 동북부 지역의 지하수중 농도는 대부분 3mg/l 이하였다. 서북부 지역에서 pH는 Ca, Mg 및 EC와 역의 상관관계가 있었으나, 동북부 지역에서는 상관성이 없었으며, 두 지역에서 모두 Ca, Mg, Na 및 $SO_4$간에는 정의 상관성을 나타내었다. 서북부 지역에서 $NO_3-N$은 pH와 역의 상관관계가 있었으며, Ca, Mg, Na, Cl, $SO_4$ 및 Cl/$HCO_3$와 정의 상관성을 나타내었으나, 동북부 지역에서는 상관성을 나타내지 않았다. D-65, D-35 및 D-41 관정의 이온조성은 인위적인 오염의 정도가 낮은 D-42 판정에 비하여 Ca, Mg, Na, Cl 및 $SO_4$가 높은 편이었다. 이와 같은 결과는 서북부 지역의 지하수가 양돈폐수에 의하여 영향을 받아 폐수중의 성분이 지하수로 유입되었기 때문에 나타난 결과라고 추정된다.

• 한국식물병리학회지
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• 제10권3호
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• pp.228-234
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• 1994

Genomic RNA was extracted from Cy strain of odontoglossum ringspot tobamovirus (ORSV-Cy) isolated from infected leaves of tobacco cv. Samsun. Size of the genomic RNA was about 6.6 kb in length. The genomic RNA was fractionated using Sephadex G-50 column chromatography into 2 fractions. They were polyadenylated at their 3'-end using E. coli poly(A) polymerase. Polyadenylated viral RNA was recovered by oligo (dT) primer adapter containing NotI restriction site and Moloney murine leukemia virus SuperScript reverse transcriptase (RNase H-). Second-strand cDNA was synthesized by using E. coli DNA ligase, E. coli DNA polymerase I and E. coli RNase H. Recombinant plasmids containing cDNAs for ORSV-Cy RNA ranged from about 800 bp to 3,000 bp. Among the selected 238 recombinants, pORCY-124 clone was the largest one covering 3'-terminal half of the viral RNA. This clone contained two restriction sites for EcoRI and XbaI and one site for AccI, AvaI, BglII, BstXI, HindIII, PstI, and TthIII 1. respectively. The clone contained partial viral replicase, a full-length movement protein and a complete coat protein genes followed by a 3' untranslated region of 414 nucleotides based on restriction mapping and nucleotide sequencing analyses. Clones pORCY-028, -068, -072, -187 and -224 were overlapped with the pORCY-124. Clones pORCY-014 and -095 covered 5' half upstream from the middle region of the viral RNA, which was estimated based on restriction mapping and partial sequence analysis. Constructed cDNA library covered more than 90% of the viral genome.

• 한국환경복원기술학회지
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• 제21권6호
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• pp.27-53
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• 2018

This study was carried out to investigate the flora of Manisan (Ganghwa-gun) from April of 2017 to August of 2018. The vascular plants identified during the 12 round field surveys were a to total of 508 taxa: 107 families, 306 genera, 456 species, 7 subspecies, 43 varieties, 1 form, and 2 hybrids. The largest families were as follows; Asteraceae (66 taxa), Poaceae (59 taxa), Fabaceae (25 taxa), Cyperaceae (25 taxa), Rosaceae (22 taxa), Liliaceae (20 taxa), Polygonaceae (17 taxa), Lamiaceae (14 taxa), Ranunculaceae (13 taxa), and Caryophyllaceae (13 taxa). Among these plants, 169 taxa were recoeded for the first time from this region. The six taxa of Korean endemic plants including Clematis brachyura Maxim., Viola seoulensis Nakai, Carex brevispicula G. H. Nam & G. Y. Chung, C. erythrobasis H. $L{\acute{e}}v$. & Vaniot, Hemerocallis hakuunensis Nakai, and Lycoris flavescens M. Y. Kim & S. T. Lee were found in this region. The vascular plants on the red list according to IUCN evaluation basis were found to be two taxa: Near Threatened (NT) species of Wikstroemia trichotoma (Thunb.) Makino, and Not Evaluate (NE) species of Tylophora floribunda Miq., respectively. The floristic regional indicator plants found in this area were 26 taxa comprising three taxa of degree IV, four taxa of degree III, seven taxa of degree II, and 12 taxa of degree I. In addition, the alien plants were identified as 49 taxa and the percentage of naturalized index (NI) was 9.7%, and urbanization index (UI) was 15.3%, respectively.

• 천문학회보
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• 제40권2호
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• pp.41.4-42
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• 2015

Outflows and jets from young stellar objects (YSOs) are prominent observational phenomena in star formation process. Indicating currently ongoing star formation and directly tracing mass accretion, they provide clues about the accretion processes and accretion history of YSOs. While outflows of low-mass YSOs are commonly observed and well studied, such studies for high-mass YSOs have been so far rather limited owing to their large distances and high visual extinction. Recently, we have found a number of molecular hydrogen (H2 1-0 S(1) at 2.12 micron) outflows in the long, filamentary infrared dark cloud (IRDC) G53.2 located at 1.7 kpc from UWISH2, the unbiased, narrow-band imaging survey centered at 2.12 micron using WFCAM/UKIRT. In IRDC G53.2 which is an active star-forming region with ~300 YSOs, H2 outflows are ubiquitously distributed around YSOs along dark filaments. In this study, we present the most prominent H2 outflow among them identified in one of the IRDC cores MSXDC G53.11+00.05. The outflow shows a remarkable bipolar morphology and has complex structures with several flows and knots. The outflow size of ~1 pc and H2 luminosity about ~1.2 Lsol as well as spectral energy distributions of the Class I YSOs at the center suggest that the outflow is likely associated with a high-mass YSO. We report the physical properties of H2 outflow and characteristics of central YSOs that show variability between several years using the H2 and [Fe II] images obtained from UWISH2, UWIFE and Subaru/IRCS+AO188 observations. Based on the results, we discuss the possible origin of the outflow and accretion processes in terms of massive star formation occurring in IRDC core.

• Journal of Information Display
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• 제7권4호
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• pp.13-16
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• 2006

II-$III_{2}-(S,Se)_{4}$ structured of phosphor have been used at various fields because they have high luminescent efficiency and broad emission band. Among these phosphors, europium doped $BaGa_{2}S_{4}$ was prepared by solid-state method. We investigated the possibility of applying [ ] due to emissive property of UV region. Also, general sulfide phosphors were synthesized by using injurious $H_{2}S$ $CS_{2}$ gas. However, this study prepared $BaGa_{2}S_{4}:Eu^{2+}$ phosphor is addition to excess sulfur under 5% $H_{2}$/95% $N_{2}$ reduction atmosphere. So, this process could involved large scale synthesis because of non-harmfulness and simple process. The photo-luminescence efficiency of the prepared $BaGa_{2}S_{4}:Eu^{2+}$ phosphor increased by 20% compared with commercial $BaGa_{2}S_{4}:Eu^{2+}$ phosphor. From this, we could conclude that the prepared $BaGa_{2}S_{4}:Eu^{2+}$ could be applied to green phosphor for white LED of three wavelengths.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1096-1099
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• 2006

$II-III_2-(S,Se)_4$ structured of phosphor have been used at various field because those have high luminescent efficiency and broad emission band. Among these phosphors, europium doped $BaGa_2S_4$ was prepared by solid-state method and we try to look into an application possibility due to an emissive property of UV region. Also, general sulfide phosphors were synthesized by using injurious $H_2S\;CS_2$ gas. However, this study prepared $BaGa_2S_4:Eu^{2+}$ phosphor is addition to excess sulfur under 5% $H_2/95%\;N_2$ reduction atmosphere. So, this process could large scale synthesis because of non-harmfulness and simple process. The photo-luminescence efficiency of the prepared $BaGa_2S_4:Eu^{2+}$ phosphor increased 20% than commercial $SrGa_2S_4:Eu^{2+}$ phosphor. The prepared $BaGa_2S_4:Eu^{2+}$ could apply to green phosphor for white LED of three wavelengths.

• Journal of Mechanical Science and Technology
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• 제17권1호
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• pp.139-145
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• 2003

Diode laser sensor is conducted to measure the gas temperature in the liquid-gas 2-phase counter flow flame. C$\_$10/H/ sub 22/ and city gas were used as liquid fuel and gas fuel, respectively. Two vibrational overtones of H$_2$O were selected and measurements were carried out in the spray flame region stabilized the above gaseous premixed flame. The path-averaged temperature measurement using diode laser absorption method succeeded in the liquid fuel combustion environment regardless of droplets of wide range diameter. The path-averaged temperature measured in the post flame of liquid-gas 2-phase counter flow flame showed qualitative reliable results. The successful demonstration of time series temperature measurement in the liquid-gas 2-phase counter flow flame gave us motivation of trying to establish the effective control system in practical combustion system. These results demonstrated the ability of real-time feedback from combustor inside using the non-intrusive measurement as well as the possibility of application to practical combustion system. Failure case due to influence of spray flame was also discussed.

• BMB Reports
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• 제31권2호
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• pp.130-134
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• 1998

An aldolase gene has been cloned from Methanococcus jannaschii. The coding region of the gene has been expressed in E. coli using a pET system to a level of 30% of total cellular proteins. The protein was purified to more than 95 % homogeneity by heat treatment and ion exchange chromatography. The protein performed an aldol condensation reaction with glyceraldehyde as substrate and dihydroxyacetone phosphate as a carboxyl donor. The protein was determined to be a type II aldolase which requires the $Zn^{2+}$ ion as a metal cofactor. This enzyme has a broad range of optimum pH (7-9) and temperature ($50-80^{\circ}C$). It shows strong stability against heat, chemical denaturants, as well as a high percentage' of organic solvents. The half-life of this enzyme at $85^{\circ}C$ is more than 24 h and it maintains more than 90% of aldolase activity in the presence of 6 M urea, 50% acetonitrile, or 15% isopropyl alcohol.

• Journal of Applied Biological Chemistry
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• 제60권3호
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• pp.257-263
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• 2017

A cellulolytic strain Y2 was isolated from soil obtained in the Canadian Alpine region. The isolate was identified as Paenibacillus sp. Y2 by 16S rRNA sequencing. When grown in LB medium supplemented with carboxymethyl-cellulose (CMC), CMCase production increased to 122.0% of that observed in LB without CMC. Culture supernatant was concentrated by ultrafiltration and 80% ammonium sulfate precipitates were separated by Hi-Trap Q and CHT-II chromatography. The purified enzyme (EG-PY2) showed a homogeneous single band and the molecular mass was estimated to be 38 kDa by SDS-PAGE. Optimum pH and temperature of the enzyme were 4.5 and $30^{\circ}C$, respectively. The half-life of enzyme activity at 50 was 140.7 min, but the enzyme was drastically inactivated within 5 min at $55^{\circ}C$. The enzyme was highly activated to 135.7 and 126.7% by 5.0 mM of $Cu^{2+}$ or $Mg^{2+}$ ions, respectively, and moderately activated by $Ba^{2+}$ and $Ca^{2+}$ ions, whereas it was inhibited to 76.8% by $Fe^{2+}$, and to ${\leq}50%$ by $Mn^{2+}$, $Co^{2+}$, $Zn^{2+}$, and EDTA. The enzyme was activated to 211.5% in the presence of 0.5 M of NaCl and greatly tolerant to 3.15M of NaCl. The enzyme showed 2.98 times higher ${\beta}$-glucanase activity than CMCase activity. Based on these results, it can be concluded that EG-PY2 is an acidophilic, cold-active, and halotolerant endoglucanase. The authors suggest it is considered to be useful for various industrial applications, such as, fruit juice clarification, acidic deinking processes, high-salt food processing, textile and pulp industries, and for biofuel production from seaweeds.