• 한국결정성장학회지
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• 제16권1호
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• pp.12-19
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• 2006

Metalorganic chemical vapor deposition (MOCYD) techniques have been applied to fabricate semiconducting ZnO thin films and nanostructures, which are promising for novel optoelectronic device applications using their unique multifunctional properties. The growth and characterization of ZnO thin films on Si and $SiO_2$ substrates by MOCYD as fundamental study to realize ZnO nanostructures was carried out. The precise control of initial nucleation processes was found to be a key issue for realizing high quality epitaxial layers on the substrates. In addition, fabrication and characterization of ZnO nanodots with low-dimensional characteristics have been investigated to establish nanostructure blocks for ZnO-based nanoscale device application. Systematic realization of self- and artificially-controlled ZnO nanodots on $SiO_2/Si$ substrates was proposed and successfully demonstrated utilizing MOCYD in addition with a focused ion beam technique.

• 한국결정성장학회지
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• 제1권2호
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• pp.34-45
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• 1991

광기능소자로 응용성이 넓은 전기광학결정 $r-6Bi_2O_3{\cdot}GeO_2$(이하 BGO로 약칭)을 EFG(Edge-defined Film-fed Growth)법에 의하여 판상단결정으로 육성하는 기초적 조건을 조사하였고 얻어진 판상단결정의 characterization 및 평가를 행하였다. 본 연구에서 얻어진 최적성장조건은 온도구배가 $22^{\circ}C$/cm 이었고 인상속도는 2.0mm/h이었다. 결정성장 최적조건에서 육성된 BGO결정은 제 2상의 석출이 없고 grain boundary가 존재하지 않으며 X선분석으로도 단결정임이 확인되었다. 육성된 판상단결정의 판면은 (100)면이었고 결정성장 방위는 <110>이었다. 육성된 판상단결정은 편광현미경하에서는 pore, void, inclusion, striation등의 성장결함이 없는 양질의 단결정이었으나 미세결함인 전위(dislocation)의 존재가 확인되었고 전위밀도는 $7.0{\times}105/cm^2$이었다.

• Journal of Korean Society for Atmospheric Environment
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• 제22권E1호
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• pp.9-18
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• 2006

Aerosol hygroscopic properties were measured by a tandem differential mobility analyzer (TDMA) system during the Aerosol Characterization Experiment (ACE)-Asia campaign from 31 March to 1 May 2001. Two high flow differential mobility analyzers (DMAs) were used to maximize the count rate on board the Center for Interdisciplinary Remotely Piloted Aircraft (CIRPAS) Twin Otter aircraft. Hygroscopic growth factor distributions of particles having initial dry nanoparticle diameters of 0.040, 0.059, 0.086, 0.126, 0.186, 0.273, 0.400, and $0.586{\mu}m$ were measured during 19 research flights. Data collected during 12 of those flights were used to investigate aerosol mixing state and the influence of aerosol source region on size-resolved hygroscopicity. The uniformity in size-resolved hygroscopicity was quantified to facilitate comparison between measurements made in different air masses. Hygroscopic growth factors are strongly dependent on source region and sizes. Mean hygroscopic growth factors were observed to be greatest when the air mass origin was from the south. The mean growth factors for continental sources decreased with initial size from 1.47 to 1.27 for $0.040{\mu}m\;and\;0.586{\mu}m$, but increased with initial size from 1.44 to 1.8 for $0.040{\mu}m\;and\;0.400{\mu}m$ dry diameters for marine sources.

• Journal of Microbiology and Biotechnology
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• 제25권4호
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• pp.431-438
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• 2015

Ever since the ban on antibiotic growth promoters (AGPs), the livestock death rate has increased owing to pathogenic bacterial infections. There is a need of developing AGP alternatives; however, the mechanisms by which AGP enhances livestock growth performance are not clearly understood. In this study, we fed 3-week-old swine for 9 weeks with and without AGPs containing chlortetracycline, sulfathiazole, and penicillin to investigate the effects of AGPs on swine gut microbiota. Microbial community analysis was done based on bacterial 16S rRNA genes using MiSeq. The use of AGP showed no growth promoting effect, but inhibited the growth of potential pathogens during the early growth stage. Our results showed the significant increase in species richness after the stabilization of gut microbiota during the post-weaning period (4-week-old). Moreover, the swine gut microbiota was divided into four clusters based on the distribution of operational taxonomic units, which was significantly correlated to the swine weight regardless of AGP treatments. Taxonomic abundance analysis indicated a negative correlation between host weight and the abundance of the family Prevotellaceae species, but showed positive correlation to the abundance of the family Spirochaetaceae, Clostridiaceae_1, and Peptostreptococcaeae species. Although no growth performance enhancement was observed, the use of AGP inhibited the potential pathogens in the early growth stage of swine. In addition, our results indicated the ecological succession of swine gut microbiota according to swine weight. Here, we present a characterization of swine gut microbiota with respect to the effects of AGPs on growth performance.

• 한국광학회:학술대회논문집
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• 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
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• pp.204-206
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• 1990

• 한국재료학회:학술대회논문집
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• 한국재료학회 1992년도 춘계학술발표회
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• pp.121-122
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• 1992

• 한국결정학회:학술대회논문집
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• 한국결정학회 2001년도 임시총회 및 추계학술대회연구발표회(한국결정학회)
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• pp.18-18
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• 2001

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.262.2-262.2
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• 2000

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1996년도 The 9th KACG Technical Annual Meeting and the 3rd Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.509-510
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• 1996

• Journal of Life Science
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• 제10권1호
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• pp.40-44
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• 2000

The SNF2/SW ATPase/helicase family comprises proteins form a variety of species with in vivo functions, such as transcriptional regulation, maintenance of chromosome stability during mitosis, and various types of DNA repair. Here, we reported the characterization of h게2+gene which was iolated by PCR amplification using the conserved domain of SNF2 motifs. Sequence analysis of PCR product showed striking evolutionary conservation among the SNF2 family of proteins. Two transcripts of 6.7 and 3.4 Lb were detected by Northern blot analysis. furthermore, the intensities of these two bands were increased by ultraviolet(UV) irradiation. These results indicate that the hrp2+ is a novel member of the SNF2 family of proteins and is one of the UV-inducible genes in S. pombe. To determine the level of transcripts of hrp2+ gene during cellular growth, Northern blot analysis were performed. This result indicates that the level of hrp2+transcript reached its maximum before cells entered the exponential growth phase. This suggests that hrp2+ gene is experssed mainly at the early stage of cell growth.