A boron-doped diamond(BDD) electrode is attractive for many electrochemical applications due to its distinctive properties: an extremely wide potential window in aqueous and non-aqueous electrolytes, a very low and stable background current and a high resistance to surface fouling. An Ar gas mixture of H2, CH4 and trimethylboron (TMB, 0.1 % C3H9B in H2) is used in a hot filament chemical vapor deposition(HFCVD) reactor. The effect of argon addition on quality, structure and electrochemical property is investigated by scanning electron microscope(SEM), X-ray diffraction(XRD) and cyclic voltammetry(CV). In this study, BDD electrodes are manufactured using different Ar/CH4 ratios (Ar/CH4 = 0, 1, 2 and 4). The results of this study show that the diamond grain size decreases with increasing Ar/CH4 ratios. On the other hand, the samples with an Ar/CH4 ratio above 5 fail to produce a BDD electrode. In addition, the BDD electrodes manufactured by introducing different Ar/CH4 ratios result in the most inclined to (111) preferential growth when the Ar/CH4 ratio is 2. It is also noted that the electrochemical properties of the BDD electrode improve with the process of adding argon.

This study investigated the effects of the post annealing temperatures on the electrical and interfacial properties of a metal-semiconductor-metal photodetector(MSM-PD) device. The interdigitate type MSM-PD devices had the structure Al(500 nm) / Ti(200 nm) / poly-Si(500 nm). Structural analyses of the MSM-PD devices were performed by employing X-ray diffraction(XRD), scanning electron microscopy(SEM) and transmission electron microscope(TEM). Electrical characteristics of the MSM-PD were also examined using current-voltage(I-V) measurements. The optimal post annealing condition for the Schottky contact of MSM-PD devices are 350℃-30minutes. However, as the annealing temperature and time are increased, electrical characteristics of MSM-PD device are degraded. Especially, for the annealing conditions of 400℃-180minutes and 500℃-30minutes, the I-V measurement itself was impossible. These results are closely related to the solid phase reactions at the interface of MSM-PD device, which result in the formation of intermetallic compounds such as Al3Ti and Ti7Al5Si12.

주의 깜박임이란 RSVP상에서 두 개 이상의 표적을 탐지할 때 먼저 제시 된 표적(T1)에 대해서는 정확성이 높지만 이후 500ms 이내의 표적(T2)에 대해서는 체계적으로 수행이 저하되는 현상을 말한다. 이를 설명하는 이론들은 주의용량결핍 모형과 주의여과지연 모형으로 분류할 수 있다. 한편, 시각적 주의 용량은 좌우 시각영역에서 독립적으로 작용하는 반시야 독립성으로 인해 다양한 과제에서 양측영역이득이 나타난다고 알려져 있다. 본 연구는 주의 용량의 반시야 독립성을 이용하여 주의 깜박임을 설명하는 두 갈래의 이론을 검증하였다. 실험 1은 T1과 T2를 포함하는 두 개의 RSVP를 양쪽 시야 영역에 나누어 제시하거나 한쪽 시야 영역에 제시하여 주의 깜박임과 양측영역이득간의 상호작용을 검증하였다. 실험 2는 하나의 RSVP에서 T1을 제거함으로써 양쪽 시야 영역에 T1과 T2가 독립된 주의용량 을 사용할 때에도 주의 깜박임이 나타나는지 확인하였다. 그 결과 두 개의 RSVP를 양쪽 시야 영역에 나누어 제시하였을 때 더 우수한 수행을 보여주었으나 (즉, 양측영역이득) 주의 깜박임과 양측영역이득의 상호작용은 나타나지 않았다. 또한, T1이 제시되지 않은 RSVP의 T2에서도 주의 깜박임 현상을 관찰할 수 있었다. 이 결과들은 주의 깜박임에 대한 주의여과지연 모형을 지지한다.

Boron-doped diamond (BDD) electrode has an extremely wide potential window in aqueous and non-aqueous electrolytes, very low and stable background current and high resistance to surface fouling due to weak adsorption. These features endow the BDD electrode with potentially wide electrochemical applications, in such areas as wastewater treatment, electrosynthesis and electrochemical sensors. In this study, the characteristics of the BDD electrode were examined by scanning electron microscopy (SEM) and evaluated by accelerated life test. The effects of manufacturing conditions on the BDD electrode were determined and remedies for negative effects were noted in order to improve the electrode lifetime in wastewater treatment. The lifetime of the BDD electrode was influenced by manufacturing conditions, such as surface roughness, seeding method and rate of introduction of gases into the reaction chamber. The results of this study showed that BDD electrodes manufactured using sanding media of different sizes resulted in the most effective electrode lifetime when the particle size of alumina used was from 75~106 μm (#150). Ultrasonic treatment was found to be more effective than polishing treatment in the test of seeding processes. In addition to this, BDD electrodes manufactured by introducing gases at different rates resulted in the most effective electrode lifetime when the introduced gas had a composition of hydrogen gas 94.5 vol.% carbon source gas 1.6 vol.% and boron source gas 3.9 vol.%.

A SrAl2O4:Eu2+,Dy3+ phosphor powder with stuffed tridymite structure was synthesized by glycine-nitratecombustion method. The luminescence, formation process and microstructure of the phosphor powder were investigated bymeans of X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). The XRDpatterns show that the as-synthesized SrAl2O4:Eu2+,Dy3+ phosphor was an amorphous phase. However, a crystalline SrAl2O4phase was formed by calcining at 1200oC for 4h. From the SEM analysis, also, it was found that the as-synthesizedSrAl2O4:Eu2+,Dy3+ phosphor was in irregular porous particles of about 50µm, while the calcined phosphor was aggregated inspherical particles with radius of about 0.5µm. The emission spectrum of as-synthesized SrAl2O4:Eu2+,Dy3+ phosphor did notappear, due to the amorphous phase. However, the emission spectrum of the calcined phosphor was observed at 520nm(2.384eV); it showed green emission peaking, in the range of 450~650nm. The excitation spectrum of the SrAl2O4:Eu2+,Dy3+phosphor exhibits a maximum peak intensity at 360nm (3.44eV) in the range of 250~480nm. After the removal of the pulseXe-lamp excitation (360nm), also, the decay time for the emission spectrum was very slow, which shows the excellent long-phosphorescent property of the phosphor, although the decay time decreased exponentially.

In this study, Seoul Terminal (Gangnam Express Bus Terminal, South Terminal, East Seoul Terminal) from a one-way mileage 200 ㎞ or more long-distance express bus and coach routes to target indoor air quality (CO₂, PM10) to investigate the interior air quality levels investigated. If the former route of PM10 in the study indoor air quality guidelines, LEVEL1, 2 (150 ㎍/㎥, 200 ㎍/㎥) although has been surveyed. PM10 concentrations of Bus 14.9 ㎍/㎥ the intercity bus (12.1 ㎍/㎥) was higher than the survey. Summer is the season of high-speed bus, CO₂, estimated at 10 before measurement guidelines from the line Ministry Level 1 (2,000 ppm) and Level 2 (3,000 ppm) meet, whereas the measurement results from Seoul to Daegu Summer off season (2,589 ppm), Seoul to Busan (2,332 ppm) from the Ministry of Environment guidelines between Level 1 (2,000ppm) were investigated to exceed. Coach Bus in Seoul and captures the summer season (2,793 ppm), Seoul to Yangyang (3,896 ppm), Seoul and Imsil (3,739 ppm) and the Ministry of Environment guidelines on Route 3 Level 1 (2,000 ppm) and Level 2 (3,000 ppm) was surveyed in excess. Based on these results, public transport operators or manufacturers of public transport vehicles properly maintained to the Public Transportation System air quality by providing guidelines for managing the use of public transport and protect people"s health and help provide a comfortable service This is expected to be able to.

In this study, we attempted to develop a convenient aluminizing process, using Al-Ti mixed slurry as an aluminum source, to control the Al content of the aluminized layer as a result of a one-step process and can be widely adopted for coating complex-shaped components. The aluminizing process was carried out by the heat treatment on disc and rod shaped S45C steel substrates with Al-Ti mixed slurries that were composed of various mixed ratios (wt%) of Al and Ti powders. The surface of the resultant aluminized layer was relatively smooth with no obvious cracks. The aluminized layers mainly contain an Fe-Al compound as the bulk phase. However, the Al concentration and the thickness of the aluminized layer gradually decrease as the Ti proportion among Al-Ti mixed slurries increases. It has also been shown that the Al-Ti compound layer, which formed on the substrate during heat treatment, easily separates from the substrate. In addition, the incorporation of Ti into the substrate surface during heat treatment was not observed.

50/50 vol% LSM-YSZ의 복합공기극(LSM=La1-xSrxMnO3(0≤x≤0.5))이 콜로이드 증착법에 의해 준비으며 주사전자현미경과 임피던스 분석기에 의해 연구되어졌다. 재현성있는 임피던스 스펙트럼들이 LSM-YSZ/YSZ/LSM-YSZ로 구성된 향상된 셀을 사용함으로써 얻어졌다. 이러한 셀들의 임피던스 스펙트럼들은 작동온도에 강하게 영향을 받았으며, 가장 안정된 조건은 900˚C에서 도달되어졌다. 900˚C에서 공기//공기 셀에 대해 측정된 전형적인 임피던스 스펙트럼들은 2개의 불완전한 호(depressed arc)로 구성되었다. LSM전극에 대한 YSZ의 첨가는 LSM-YSZ 공기극의 저항 감소를 가져왔으며, 전해질 표면의 불순물의 영향을 제거하기 위한 연마는 공기극 저항을 더욱 감소시켰다. 또한 촉매층(Ni 혹은 Sr)을 가진 LSM-YSZ 전극은 촉매층이 없는 경우에 비해 공기극 저항의 감소를 가져왔다. LSM-YSZ 공기극 저항은 전극조성, 전해질의 형태, 인가 전류에 의해 영향을 받았다.

SrAI2O4:Eu2+를 합성하여 장잔광 축광재료로서 가장 중요한 발광특성과 장잔광특성을 조사하였다. 융제로서 B2O3를 3wt% 첨가한 SrCO3, Eu2O3, AI2O34의 혼합분말은 1000˚C이상에서 모체결정인 SrAl2O4의 단일상이 형성되었으나, 장잔관 형광체로서 최적의 합성조건은 1300˚C, 3시간이었다. 그리고 SrAI2O4:Eu2+는 부활제인 Eu2+의 4f65d1 →4f7천이에 기인하여 황록색발광영역의 520nm(2.384eV)를 최대 발파장으로 하는 450~650nm의 폭넓은 발광스펙트럼을 보였으며, 또한 발광파장을 520nm로 고정하여 측정한 여기스펙트럼의 최대 흡수피크는 360nm이고 250nm에서 480nm의 넓은 범위에서 흡수스펙트럼이 관찰되었다.

Si(100)기판상에 여러 가지 두께의 Au박막을 선행 증착(pre-deposition)한 후, 각각의 Au박막상에서의 Cu-MOCVD박막의 초기 핵생성과 성장 기구를 고찰하였고, 또한 각 계면에서의 상호 확산 거동을 여러가지의 분석 장비를 이용하여 조사하였다. 30Å두께의 Au 박막은 수소 가스 분위기중의 열처리에 의하여 평탄한 표면 상태에서 불연속의 응집된 도상(island)형태로 변화(Si 전체 표면중 약 20%)하였다. 반면에 1500Å두께의 Au박막상에서 성장한 Cu-MOCVD박막은 두께 증가에 따른 미세구조의 차이, 즉 Cu박막중으로 Au원자의 확산여부는 Au박막에 유기되는 열응력(thermal stress)을 완화하는 과정에서 일어난 결과이다.

Three swamps, Daepyeong, Jilnal and Yujeon, distributed in Beobsu-myeon and Gunbug-myeon, Haman-gun, Gyeongsangnam-do, are investigated geomorphologically and geologically. The topography of the swamp area is low in general, though the northern side of Nam River has somewhat high mean altitude than the southern side of the river, consisting of lowly land, which is plane or peneplane. The swamps are only found in the southern side of the river, The swamp area is composed of greenish gray siltstone and fine sandstone of the Cretaceous Haman Formation, General strike of the rocks is N80°E, and dips 10°S. Crests of ridges of north-south trending hills are occupied with dyke rocks. The swamps are interpreted to be formed by migrated meadering course of Nam River, The meandering river migrated towards north leaving swamps. Gradually rising underground water-table was also the cause of swamp making. According to the size analysis of the swamp sediments, the mean size is 7φ sorting 2φ, and skewness +0.7φ∼-0.3φ Largest kurtosis is 1.20φ at the Yujeon swamp. The coarse swamp sediments is composed mostly of rock fragments of the Haman Formation, and fine-grained sediments consist of 50% quartz, 25% feldspar, 7% muscovite, 17% rock fragments and 1% biotite. Organic matter contents of the bottom sediments range from 2.53% to 9.82%, averaging 5.56% except two samples which have abnormally high contents of organic matter.