• 한국광물학회지
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• 제18권3호
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• pp.227-236
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• 2005

밀양점토광상의 알루미늄이 풍부한 다이아스포아 단괴에서 열수변질 기원 전기석은 집합체나 미립으로 산출한다 대부분의 전기석 결정은 미세한 대구조가 특징적인데, 이는 열수변질 작용동안 개방계의 유체혼합과 같은 변동이 심한 환경에서 형성되었음을 지시한다. 본 전기석의 화학적 진동누대 구조의 양상은 결정축의 방향과는 무관하게 흡사한 특징을 보인다. Mg는 결정성장 초기, Fe는 후기 단계동안에 부화되었으며, Fe/Mg의 비는 규칙적으로 진동함을 보여 준다. 화학분석, 후방산란영상(BSE), X-선 화학분석도에 따르면 전기석내 진동누대구조는 Fe와 Mg 함량변화에 주로 제어되었으며 봉소함량의 기여도는 미미하다. 전기석이 다이아스포아와 딕카이트로 변질되는 것으로 볼 때 전기석은 B, Fe, Mg의 활동도가 감소하면서 이들 고알루미나 광물에 비하여 불안정해 진다. 그러므로 열수계내 알루미늄 활동도가 전기석의 안정성을 제어하는 것으로 볼 수 있다.

• 한국수산과학회지
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• 제30권3호
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• pp.367-376
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• 1997

Vibrio vulnificus is a gram-negative, halophilic, oxidase-positive, lactose-positive, motile, rod shaped bacterium that has been associated with primary septicemia and wound infection. Elucidating the growth and survival of V. vulnificus in ecological conditions is of great importance to develop sanitary measure against this microorganism. Thus we simulated the ecological conditions and evaluated the effect. About $10^5\;CFU/ml$ of V. vulnificus was inoculated to fresh water, brackish water $(1\%\;NaCl)$, sea water $(3\%\;NaCl)$, and bottom deposit solution. The same concentration of V. vulnificus was also inoculated to distilled water, $1\%\;NaCl$ solution and $3\%\;NaCl$ solution as controls. These were stored at 4, 15 and $25^{\circ}C$, respectively and were used to assess the effects of temperature and salinity on the survival of V. vulnificus. In fresh water V. vulnificus could not survive regardless of storage temperature. In case of brackish water and sea water survival time of V. vulnificus was the longest at $25^{\circ}C$, and the number of V. vulnificus was decreased most rapidly at $4^{\circ}C$. V. vulnificus survived longer in brackish water than in any other conditions. In bottom deposit solution containing brackish water, the survival time of V. vulnificus was longer and the rate of decline was slower than that in brackish water. These results indicate that both biological and physicochemical factors such as temperature and salinity could affect survival of V. vulnificus. V. vulnificus, damaged in normal fresh water, did not grow on TCBS agar of selective plating medium but grew on BHI agar plate; However, V. vulnificus was recovered by addition of salt and nutrient materials.

• 한국광물학회지
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• 제17권4호
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• pp.357-364
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• 2004

동양활석광상에서 산출되는 백운석기원 활석(활석 I)과 투각섬석기원 활석(활석 II)의 차이를 밝히기 위해 광물조성을 연구하였다. 활석 II의 철과 알루미늄 평균 함량이 각각 2.18 wt%와 0.31 wt%이고, 활석 각각 1.48 wt%와 0.08 wt%로서 전자의 경우가 높다. 활석 I보다 활석 II에서 Mg/(Mg+Fe+Mn)비가 일정한 값으로 꾸준히 낮고, 마찬가지로 Al 함량이 높은 것은 이들의 근원물질인 투각섬석과 백운석의 조성의 차이에서 기인된 것으로 보인다. 활석 II에서의 Al과 Fe가 투각섬석 경우보다 부화된 것은 변질작용 중에 이들 원소의 불유동성과 열수용액의 급격한 확산에 기인된 것으로 해석되며, 후자의 경우 활석 ll의 불완전성장과 함께 순간적인 성핵을 촉진시키게 된다. 광석 중에 투각섬석기원 활석의 양이 증가하면 투각섬석 자체의 함량과 Al과 Fe 등의 불순물 증가로 인해 광석의 품위는 저하된다.

• Journal of Welding and Joining
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• 제6권2호
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• pp.30-39
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• 1988

Generally, as the welded region of weld structures has the incomplete bead and welded deposit which are able to behave like the surface cracks occasinally, there is a high possibility that the fatigue fracture of the weld structures is due to the surface cracks on the wlded region. This study was done to investigate the effects of post weld heat treatment (PWHT) on the fatigue behaviors of the surface crack of the heat affected zone (HAZ) for the multi-pass welds under the repetitive pure bending moment. The obtained results are summarized as follows : 1. The crack grows to the depth direction initially as the number of cylces increase, the amount of crack length is increased for the surface dir3ction and cive versa for the depth direction. 2. The fatigue life is increased in a order of as weld, PWHT specimens and parent. 3. As the number of cycles increase, the crack length is increased to th surface direction. The increase of the depth length is blunted at the center of specimen thickness. 4. The fatigue crack growth of PWHT specimens to the surface direction is dependent upon the holding time and applied stress during PWHT. In order words, the crack growth rate decreases with the holding time and increases with the applied stress during PWHT. 5. As the crack grows, the aspect formed in the course of crack propagation approaches to semicircle for parent and ellipse with the largest semidiameter for PWHT ($1/4hr, 15kgf/mm^2$) 6. At depth direction, it is difficult to apply to the paris' equation because of the scattered data between the crack growth rate and the stress intensity factor range.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.282-282
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• 2013

The antimony sulfide ($Sb_2S_3$) thin films were deposited using the gas phase method which known as atomic layer deposition (ALD) on mesoporous micro-films. Tris (dimethylamido) antimony (III[$(Me_2N)_3Sb$] and hydrogensulfide ($H_2S$) were used as precursors to deposit $Sb_2S_3$. Self-terminating nature of $(Me_2N)_3Sb$ and $H_2S$ reaction were demonstrated by growth rate saturation versus precursors dosing time. Absorption spectra and extinction coefficient were investigated by UV-VIS spectroscopy. Scanning electron microscopic analysis and X-ray photoelectron spectroscopy (XPS) depth profile were employed to determine the conformal deposition.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.889-891
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• 1998

Copper films have been deposited on glass substrate via a thermal decomposition of copper(II) formate using a focused $Ar^+$ laser emitting at 514 nm. The growth kinetics of these Cu films was investigated as a function of laser power and scan speed which varied in the range of 70-150 mW and 0.1-20 mm/s, respectively. The resistivity of the copper films was a factor of about 20 higher than· that of bulk value, but the resistivity decreased due to changes in morphology and porosity of the deposit after annealing at $300^{\circ}C$, 5 min. and was about $10{\mu}{\Omega}cm$.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1119-1122
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• 2005

A selective deposition of Co thin films for thin film transistor gate electrode has been carried out by the growth with combination of micro-contact printing and metal organic chemical vapor deposition (MOCVD). This results in the elimination of optical lithography process. MOCVD has been employed to selectively deposit Co films on preformed OTS gate pattern by using micro-contact printing (${\mu}CP$). A hydrogenated amorphous silicon TFT with a Co gate selectively formed on SAMs patterned structure exhibited a subthreshold slope of 0.88V/dec, and mobility of $0.35cm^2/V-s$, on/off current ratio of $10^6$, and a threshold voltage of 2.5V, and thus demonstrating the successful application of the novel bottom-up approach into the fabrication of a-Si:H TFTs.

• Corrosion Science and Technology
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• 제2권4호
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• pp.197-201
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• 2003

In this study, Ni-P layers were electroplated on the surface of stainless steel in order to investigate the effects of an additive and agitation on their mechanical properties and microstructure. The concentration of the additive in the plating solution increased, the pores formed in the layer decreased, while the residual stress developed in the layers during electroplating increased. Agitation of the solution during electroplating was observed to force to increase local pores in the layer, which lowers its tensile properties. Grain growth was suppressed due to very fine $Ni_3P$ precipitates formed at its grain boundaries during heat treatment at $343^{\circ}C$ for 1 hr in air.

• 한국표면공학회지
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• 제47권3호
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• pp.116-120
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• 2014

The addition of cyclo propane carbonyl (cpc) to chromium electroplating bath resulted in a chromium deposit which had greatly improved mechanical properties compared to conventional chromium deposits in condition of heat treatment at high temperature. The as-deposited layers had a Vicker's hardness of about 1170, which is comparable to that of conventional chromium plating deposits. With annealing, the hardness goes through a maximum of 1650 at $600^{\circ}C$. Generally speaking, the hardness of conventional plating decreases monotonically with heat treatment. X-ray diffraction show that annealing up to above $400^{\circ}C$ causes formation and growth of chromium crystallites and that chromium carbides form at above $500^{\circ}C$ temperature.

• Corrosion Science and Technology
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• 제9권4호
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• pp.171-174
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• 2010

MAO (micro-arc oxidation) is an eco-friendly convenient and effective technology to deposit high-quality oxide coatings on the surfaces of Ti, Al, Mg and their alloys. The roles of the electrolyte concentration and relative cathode electrode area sizes in the grown oxide film during titanium MAO were investigated. The higher the concentration of the electrolyte, the lower the $R_{total}A$ value. The oxide film produced by the lower concentration of the electrolyte is thinner and less uniform than the film by the higher concentration, which is thick and porous. The cathode area size must be bigger than the anode area size in order to minimize the voltage drop across the cathode. The ratio of the cathode area size to the anode area size must be bigger than 8. Otherwise, the cathode will be another source for voltage drop, which is detrimental to and slows down the oxide growth.