• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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• pp.347-352
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• 1996

Studies on tile microstructural and compositional changes in sensitized Ni base Alloy 600 by laser surface melting have been carried out using TEM equipped with EDXA. The microstructure of the laser melted zone was mainly consisted of fine cells, and along the cell and grain boundaries, Cr enrichment due to its segregation was observed. Cr carbides having formed along the grain bundaries during the sensitization treatment have been completely dissloved. The cell walls were decorated with dislocations and the very tiny precipitates, found to be Ti(CN) type, were distributed randomly along the cell walls with tangled dislocations around them.

• 한국진공학회지
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• 제5권2호
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• pp.107-112
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• 1996

Thin films of $Pb(Zr_xTi_{1-x})O_3$)PZT) were grown on $Pt/SiO_2/Si(100)$ at various temperatures by RF magnetron sputtering method. Surface morphology of these films were studied by using Atomic Force Microscopy(AFM). These films were also analyzed by using Atomic Force Microscopy(AFM). These films were also analyzed by using X-ray photoemission spectroscopy(XPS) for determining their chemical composition and their depth profile. It was found that the films grown at the substrated temperature of $300^{\circ}C$ have much more smooth surface characteristics in comparison to those films grown at room temperature, which may be explained in terms of surface mobility of ad-atoms such as Pb. It was also found that Pb enrichment in the near surface region enhanced for the films grown at higher substate temperature.

• Fisheries and Aquatic Sciences
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• 제5권4호
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• pp.302-307
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• 2002

The characteristics of trace metals were investigated in the sediments of the Mokpo coastal area, southwestern coast of Korea. Surface sediments were collected in September 3, 2002 after a strong rain event. The sampling sites were categorized into the inner and outer harbour based on salinity distribution and difference of trace metal concentration was evidence between these two zones. The enrichment factor (E' F) of Zn and Cr were high at the mouth of Mokpo Harbour and $E \cdot F$ of Cu was high at the east-south of Dali Island. One hundred percent of Mn and Pb samples and $40\%$ of Zn samples had E' F higher than 1 suggesting that they are accumulated in the entire outer of Mokpo Harbour. Trace metals appeared to be accumulated in the inner harbour by input of sediments in the discharged freshwater from Young-San River during strong rainfall whereas they were influenced by natural sedimentation and human activities in part.

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 추계 총회 및 학술발표회
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• pp.65-66
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• 1997

1. 서론 : 현재의 막분리 기술로는 단 단계 분리공정(single-stage separation)으로 약 40%의 산소농축공기(oxygen-enriched air)를 얻을 수 밖에 없지만 심냉법(cryogenic techniques)보다는 에너지 소비율이 적으며, 공정이 비교적 간단하기 때문에 용도에 따라 순 산소를 꼭 필요로 하지 않는 제철소, 발전소 등의 연소분야, 호흡기 환자를 위한 의료분야, 생물공학이나 항공기 분야 등에 편리하게 이용될 수 있다. 이와 같이 용도가 다양한 산소를 분리막을 이용하여 보다 편리하고 값싸게 얻기 위해서는 산소와 질소의 막투과에 대한 새로운 지식을 얻고 막투과가 기체의 어떤 성질에 지배되고 있는가를 조사할 필요가 있다. 본 연구에서는 고무상 고분자막(rubbery polymer membrane)에 대한 산소/질소의 수착특성과 순수한 기체의 투과율(permeation rate)을 기초로 하여 혼합기체의 투과율, 분리인자(separation factor), 막분리 공정변수에 의한 중공사 분리막에서의 기체분리특성에 대하여 연구하였다.

• 한국막학회:학술대회논문집
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• 한국막학회 1995년도 제3회 심포지움 (분리막 연구의 최신동향)
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• pp.21-22
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• 1995

Gas separation science and technology is among the most rapidly growing areas involving membrane-based processes. Nitrogen enrichment of air, hydrogen recovery from a broad array of stream types, and removal of acid gases from natural gases are typical of the applications in this field. Great progress has been made in the discovery of guidelines optimization of polymer structures with simultaneously high permeabilities and selectivities for these important gas pairs. The development of thin-skinned asymmetric hollow fibers have also provided structures with extremely high permeation fluxes. Especially in the case of O$_{2}$/N$_{2}$ separations, the rate of improvements in new polymeric materials for gas separations appears to be slowing to a halt. Evidence will be presented, however, that the practical tradeoff between membrane permeability and selectivity has not been reached.

• 미생물학회지
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• 제30권6호
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• pp.495-500
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• 1992

Photosynthetic bacteria which can utilize ferulate as a sole carbon source for their metabolic activities were isolated from soils by liquid enrichment culture technique. The strain P-1 was selected by the highest capability of degrading ferulate in aerobic and anaerobic conditions. The strain P-1 was rod-shaped with its motility, strained gram negatively and could not utilize sulfur compounds. This strain has the bacteriochlorophyll a group I carotenoid and membrane structures like lamellae. As the results of physiological, morphological and cultural charactderistics, the isolate was identified as Rhodopseudomonas plaustris, one of the purple nonsulfer bacteria. The strain P-1 utilized 2mM/day in aerobic condition and 0.86 mM/day in anaerobic condition.

• 미생물학회지
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• 제25권2호
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• pp.129-136
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• 1987

영남작물시험장에서 질소비료 공급없이 재배합 40종의 수도품종으로부터 출수기전의 수도근권의 질소고정력을 in situacetylene 환원력 측정방법으로 시험한 결과 Azospirillum 균의 무질소 malate 배지에서 얻은 균주와 상관관계를 보였다. 이 중 질소고정력이 높은 6종의 Azospirillum을 분리 동정한 결고 5종은 A. lipoferum, 1종은 A. brasilense임을 확인한 후 이들 6종의 Azospirillum들의 당이용성, biotin 요구성, 항생제저항성, auxin 생산성, plasmid profile 및 균체단백질 pattern을 비교 분석하였다.

• 아동학회지
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• 제36권6호
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• pp.39-57
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• 2015

This study aimed to confirm the usefulness of a "Traditional Play Program" in a self-esteem and social competency enrichment program at a Community Child Center. The subjects of this research comprised 12 children attending L Community Child Center in M city and participated in a "Traditional Play Program" for each 70minutes every week through total 10 sessions running from July 28th to September 29th in 2014. The collected data were analyzed by the Mann-Whitney & Wilcoxon test as non-parametric test, in addition to the progressive recording method for behavior observation. The results of this study indicate that a "Traditional Play Program" enriches the self-esteem and social competence of children who gets more vigorous activity sociality initiative respectively, and proves the usefulness for a Community Child Center.

• 대한기계학회논문집B
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• 제30권1호
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• pp.82-86
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• 2006

Carbon nanotubes have attracted much attention as future mechanical and electronic materials. However, manipulating techniques are not well developed yet. Here we propose to use electrostatic drop-on-demand devices to eject micro-droplets containing micelle-suspended single-walled carbon nanotubes. A simple electrostatic force analysis and photographic studies of droplet ejection process are presented. The analytical analysis shows that semiconducting species have higher electrostatic force density. However, enrichment of specific electronic types is not clear at large size droplets produced in this study. A micro-scale jetting device is being produced to prove the suggested behavior.

• 한국초등과학교육학회지:초등과학교육
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• 제23권4호
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• pp.279-286
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• 2004

The purpose of this study is to develop and apply effective teaching strategies and program for the gifted-in-science. The teaching material for the gifted students was focussed on microscope. This study consists of three steps according to the enrichment triad model of Renzulli. Firstly, the gifted students investigate and express themselves for theological backgrounds, for examples, kinds, structure and use in various ways of microscope. It is to provide basic data for the effective ideas and interest which help students have the appropriate microscopic conceptions. In the second step, it contains understanding of a term and function of microscope, making of simple microscope, principle of a statue focusing and size estimation of an outline of subjects by scientific investigation activity. Lastly, it focussed on enlargement of post-learning through investigation of relationship with inter-science and experiments using microscope. Therefore, it was concluded that this study may help teachers reconsider scientific program development for the gifted or enriched students and to be successful in the teaching-learning processes.