• Applied Biological Chemistry
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• 제9권
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• pp.111-118
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• 1968

제주도(濟州道 ) 목야조성지(牧野造成地)의 흑색(黑色) 및 적색화산회토양(赤色火山灰土壤)에 대(對)한 7개목초(個牧草)의 토양인산(土壤燐酸) 이용력(利用力)을 $P^{32}$를 사용(使用)하여 조사(調査)하고 토양(土壤)의 각종(各種) 유효(有效) 인산(燐酸) 및 형태별(形態別) 분별정량(分別定量)을 하여 알맞은 유효인산(有效燐酸) 정량법(定量法)을 찾고자 하였던바 다음과 같은 결과(結果)를 얻었다. 1) 목초별(牧草別) 토양인산(土壤燐酸) 이용력(利用力)은 Italian rye grass${\gg}$ Soybean> cassia> corn> weeping love grass${\gg}$ Korean Lespedeza> Red Clover의 순(順)이며 A-value$(kgP^{2}O^[5}/ha)$가 1000이상(以上) $200{\sim}500$과 40이하(以下)의 세 가지로 대별(大別)된다. 2) 흑색토양(黑色土壤)은 적색토양(赤色土壤)에 비(比)해 무기인산(無機燐酸)이 배(培)가 되지만 목초(牧草)가 흡수(吸收)하는 유효인산량(有效燐酸量)에는 차이(差異)가 없음으로 유효(有效) 인산추출액(燐酸抽出液)은 두 토양(土壤)에 동량(同量)으로 추출(抽出)되는 것이라야 한다. 3) 목초별(牧草別) 흡수이용력(吸收利用力)에 맞는 유효인산추출액(有效燐酸抽出液)은 원토건중당(原土乾重當) 최고(最高) 20 ppm을 침출할 수 있는것과 최소(最小) 100 ppm 이상(以上) 추출(抽出)할 수 있는 두 개의 추출제(抽出劑)가 추정(推定)되며 전자(前者)는 이용력(利用力)이 약(弱)한 목초(牧草)에 후자(後者)는 이용력(利用力)이 강(强)한것에 적용(適用)되고 전자(前者)는 Truog 법(法)이 사용(使用)될 수 있으나 후자(後者)는 해당(該當)한 추출법(抽出法)은 사용(使用)된것들 중(中)에는 없었다. 4) 두과목초(荳科牧草)는 T/R 치(値)와 pdF(비료(肥料)에서 유래(由來)한 식물체무백분비(植物體燐百分比)간(間)에 5% 수준(水準)에서 부상관(負相關)이 있고 T/R가 5이상(以上)에서 50% 이하(以下)의 %pdF를 T/R가 5 이하(以下)에서 80% 이상(以上)의 %pdF를 보였으나 화본과(禾本科)에서는 아무런 상관(相關)이 없었다.

• 대한치과보철학회지
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• 제45권2호
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• pp.169-181
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• 2007

Statement of problem: Titanium is well known as a proper metal for the dental restorations, because it has an excellent biocompatibility, resistance to corrosion, and mechanical property. However, adhesion between titanium and dental porcelains is related to the diffusion of oxygen to the reaction layers formed on cast-titanium surfaces during porcelain firing and those oxidized layers make the adhesion difficult to be formed. Many studies using mechanical, chemical and physical methods to enhance the titanium-ceramic adhesion have been actively performed. Purpose: This study meant to comparatively analyse the adhesion characteristics depending on different titanium surface coatings after coating the casts and wrought titanium surfaces with Au and TiN. Material and method: In this study, the titanium specimens (CP-Ti, Grade 2, Kobe still Co. Japan) were categorized into cast and wrought titanium. The wrought titanium was cast by using the MgO-based investment(Selevest CB, Selec). The cast and wrought titanium were treated with Au coating($ParaOne^{(R)}$., Gold Ion Sputter, Model PS-1200) and TiN coating(ATEC system, Korea) and the ultra low fusing dental porcelain was fused and fired onto the samples. Biaxial flection test was done on the fired samples and the porcelain was separated. The adhesion characteristics of porcelain and titanium after firing and the specimen surfaces before and after the porcelain fracture test were observed with SEM. The atomic percent of Si on all sample surfaces was comparatively analysed by EDS. In addition, the constituents of specimen surface layers after the porcelain fracture and the formed compound were evaluated by X-ray diffraction diagnosis. Result: The results of this study were obtained as follows : 1. The surface characteristics of cast and wrought titanium after surface treatment(Au, TiN, $Al_2O_3$ sandblasting) were similar and each cast and wrought titanium showed similar bonding characteristics. 2. Before and after the biaxial flection test, the highest atomic weight change of Si component was found in $Al_2O_3$ sandblasted wrought titanium(28.6at.% $\rightarrow$ 8.3at.%). On the other hand, the least change was seen in Au-Pd-In alloy(24.5at.% $\rightarrow$ 9.1at.%). 3. Much amount of Si components was uniformly distributed in Au and TiN coated titanium, but less amount of Si's was unevenly dispersed on Al2O3 sandblasting surfaces. 4. In X-ray diffraction diagnosis after porcelain debonding, we could see $Au_2Ti$ compound and TiN coating layers on Au and TiN coated surfaces and $TiO_2$, typical oxide of titanium, on all titanium surfaces. 5. Debonding of porcelain on cast and wrought titanium surface after the biaxial flection is considered as a result of adhesion deterioration between coating layers and titanium surfaces. We found that there are both adhesive failure and cohesive failure at the same time. Conclusion: These results showed that the titanium-ceramic adhesion could be improved by coating cast and wrought titanium surfaces with Au and TiN when making porcelain fused to metal crowns. In order to use porcelain fused to titanium clinically, it is considered that coating technique to enhance the bonding strength between coating kKlayers and titanium surfaces should be developed first.

• Korean Chemical Engineering Research
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• 제56권1호
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• pp.119-124
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• 2018

아닐린과메탄올의산화 카르보닐화방법에의한 Methyl N-phenyl carbamate 제조는 기존의포스겐을사용하는폴리머의 단량체 생산공정을 대체할 수 있는 환경 친화적인 공정으로 많은 관심을 가지고 있다. 본 연구에서는 담지체로 Y-zeolite, $SiO_2$, $Al_2O_3$를 사용하여 불균일화 촉매를 제조하였고, 제조 된 불균일화 촉매를 이용하여 아닐린과 메탄올로부터 산화카르보닐화 연속운전을 시도하였다. 회분식반응기를 이용하여 담지체를 결정하였으며, 담지된 palladium 촉매를 이용하여 조촉매의 영향과 반응온도, 반응압력 등 여러 반응최적조건을 확립하였다. 최적의 반응조건 MPC의 수율은 98.6% 였으며, 반응속도론적 연구를 수행하였다. 각 반응온도의 반응속도상수로부터 얻어진 활성화 에너지는 각각 E=82.38 kJ/mol, E=66.20 kJ/mol 이었다. 또한 확립된 반응조건에서 장시간 연속운전을 수행하여 카바메이트 공정 개발을 위한 기초자료를 구하였다.

• 한국수소및신에너지학회논문집
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• 제18권4호
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• pp.406-412
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• 2007

An experimental study on the design of a catalytic combustor for 1.6 kW MCFC system has been performed. The roles of the catalytic combustor are to completely burn anode off-gas and to supply sufficient $CO_2$ to cathode channels. In order to avoid hot spot or fuel slippage, flow uniformity at the catalyst inlet was achieved by installing two crossing perforated plates between the catalyst and the mixing chamber with minimal pressure drop. A Pd/Ce/Ni-$Al_2O_3$ catalyst was used for complete combustion of the off-gas at GHSV=36,000.

• International Journal of Automotive Technology
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• 제6권6호
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• pp.591-598
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• 2005

A three-way catalyst system of a natural gas vehicle (NGV) has characteristics of higher fuel consumption and higher thermal load than a lean-bum catalyst system. To meet stringent emission standards in the future, NGV with the lean-bum engine may need a catalyst system to reduce the amounts of HC, CO and NOx emission, although natural gas system has low emission characteristics. We conducted experiments to evaluate the conversion efficiency of the NOx reduction catalyst for the lean-burn natural gas engine. The NOx reduction catalysts were prepared with the ${\gamma}-Al_{2}O_3$ washcoat including Ba based on Pt, Pd and Rh precious metal. In the experiments, effective parameters were space velocity, spike duration of the rich condition, and the temperature of flowing model gas. From the results of the experiments, we found that the temperature for maximum NOx reduction was around $450^{\circ}C$, and the space velocity for optimum NOx reduction was around $30,000\;h^{-1}$ And we developed an evaluation model of the NOx reduction catalyst to evaluate the conversion performance of each other catalysts.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.24-24
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• 1998

반도체장비를 포함하는 초고진공장비의 園훌化가 급속히 그리고 절실히 요구되고 있는 것이 현실정이다. 當面해서 실현할 국산진공장비의 대상은 廣範圍하다. 즉, 각종 진공 pump ( (rotary, dry, diffusion, cryo, ion, turbo melecular pump), 진공 chamber, 진공 line, gate valve 를 위 시 한 진공 V머ve, flange, gasket, fl않d야lU, mainpulater 퉁 진공 部品이 다. 진공계 의 핵심 은 適切하고 優良한 진공재료의 선태파 사용이다. 진공장비는 사용자가 원하는 진공도를 원하 는 시간 동안 륨空度를 유지해 주어야 한다. 진공재료 선태의 기준사항은:(1) 기체의 透過성 (2) 薰했훌 (3) 혔體放出특성 - -outgassing과 degassing- (4) 機械的 량훌度 (5) 온도 의존성 (6) 化學톡성 (7) 加I성 및 鎔接 성 (8) 課電특성 (9) 磁氣특성 (10) 高速함子 및 放射線 특성 (11) 經濟성 및 調達생 둥이 다. 우량한 초고진공계재료는 풍부하게 개발되어 왔고, 또 新材料들이 개발되고 있다. 여기에서는 주로 초고진공 내지는 극고진공계의 構造材料, 機能材料, 部品材料 일반파 몇가지 신재료의 특 성에 관해서 記述한다. M Mild SteeHSAE, 1112, 1010, 1020, 1022, etc)., S Stainless SteeHAlSI, 304, 304L, 310, 316, 321, 347): 구조재료, chamber, fl하1ges A Aluminum과 Alloys (1060, 1100, 2014, 4032, 6(뻐1): 구조재료, chamber, flanges, gaskets A AI, Al 떠loy는 SS에 代替하는 역 할올 시 작하고 있다. C Copper, Copper Alloys(C11$\alpha$)0, C26800, C61400, Cl7200): 내장인자, gasket, cryopanel, tubing T Titanium, Ziriconium, Haf띠um 및 Alloys: 특히 Ti은 10n pump 용 getter material 이 외 에 U UHV,XHV용 chamber계로서 관심올 끌고 있다. N Nickel, Nickel Alloys (200, 204, 211, monel, nichrome): 부식 방지 , 전자장치 , 자기 장치 귀 금속(Ag, Au, Pt, Pd, Rh, Ir, Os, Ru): 보조부품, gasket, filament, coating, thermocouple, 접 합부위 T TiC, SiC, zrC, HfC, TaC 둥의 탄화물과, BN, TiN, AlN 동의 질화물, 붕화물이 둥장하고 었 다. 유리: Soda Lime, Borosilicate, Potash Soda Lead: View Port, Chamber envelope C Ceramics: AlZ03, BeO, MgO, zrOz, SiOz, MgOzSiOz, 3Alz032SiOz, Z$textsc{k}$hSiOz S상N4: e electrical, thermal insulators, crucibles, boats, single crystals, sepctr려 windows 저자는 최근 저자들이 발견한 Zr-Ti-Cu-Ni-Be amorphous alloys coated cham뾰r가 radiation p proof로 이용될 수 있는 사실을 점검하고 었다 .. Z.Y. Hua 들은 Cs3Sb를 새로운 photocathode 재료로 보고하고 있다.