• 한국결정성장학회지
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• 제20권2호
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• pp.74-79
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• 2010

The synthesis and reactivities of molybdenum carbide crystallites were examined in this study. Especially, the effect of synthesis conditions were scrutinized on the preparation of molybdenum carbide crystallites. In order to perform this purpose, various characterization techniques such as BET surface area and oxygen uptake measurements were employed for the synthesized molybdenum carbide crystallites. First of all, the molybdenum carbide crystallites were synthesized using molybdenum oxide crystallites and methane gas or methane-hydrogen mixture. The experimental results showed that BET surface areas ranged from $7.4m^2/g$ to $31m^2/g$ and oxygen uptake values varied from $8.1{\mu}mol/g$ to $24.3{\mu}mol/g$. The Mo compounds were found to be active for ammonia decomposition reaction. Even though there are some molybdenum carbide crystallites that were exceeded by Pt/$Al_2O_3$ crystallite, the steady state reactivities for other molybdenum carbide crystallites were comparable to or even higher than that determined for the Pt/$Al_2O_3$ crystallite. These results implied that molybdenum carbide crystallites could be one of the promising crystallites that might be substitutes for Pt-like noble metal crystallites in the petroleum processes.

• 한국융합학회논문지
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• 제11권11호
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• pp.183-187
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• 2020

LCD BLU의 CCFL 전극에 사용되는 몰리브덴 전극의 주요소재인 몰리브덴 컵과 몰리브덴 핀은 국내 가공기술이 개발되지 못하여 전량 일본에서 수입하여 사용되고 있어 CCFL 제조업체들의 납기 및 경쟁력에 부담을 주고 있다. 본 연구에서는 LCD BLU의 CCFL 전극에 사용되는 몰리브덴 핀의 제조 기술을 개발하는 연구로 직선처리 기술개발, 몰리브덴 와이어 표면처리 기술개발, 와이어 절단기술 개발, 몰리브덴 핀의 제작, 검사용 JIG와 Fixture 설계 및 제작, 몰리브덴 핀 시제작 및 해석, 몰리브덴 핀 전수검사 기술개발에 관한 연구를 수행하였으며 본 논문에서는 몰리브덴 핀 제작에 있어 전수검사기 융합설계에 대한 연구를 다루고자 한다.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1443-1444
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• 2012

• 한국융합학회논문지
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• 제11권6호
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• pp.197-201
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• 2020

LCD BLU의 CCFL 전극에 사용되는 몰리브덴 전극의 주요소재인 몰리브덴 컵과 몰리브덴 핀은 국내 가공기술이 개발되지 못하여 전량 일본에서 수입하여 사용되고 있어 CCFL 제조업체들의 납기 및 경쟁력에 부담을 주고 있다. 본 연구에서는 LCD BLU의 CCFL 전극에 사용되는 몰리브덴 핀의 제조 기술을 개발하는 연구로 직선처리 기술개발, 몰리브덴 와이어 표면처리 기술개발, 와이어 절단기술 개발, 몰리브덴 핀의 제작, 검사용 JIG와 Fixture 설계 및 제작, 몰리브덴 핀 시제작 및 해석, 몰리브덴 핀 전수검사 기술개발에 관한 연구를 수행하였으며 본 논문에서는 몰리브덴 핀제작 및 검사용 JIG and Fixture의 설계 및 제작에 대한 연구를 다루고자 한다.

• 대한화학회지
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• 제29권4호
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• pp.372-381
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• 1985

치환 8-퀴놀린올의 옥소몰리브덴(V)착물을 합성하고 착물의 원소분석, 자외선스펙트럼, 전자스펙트럼 및 전도도를 측정하였고 옥소몰리브덴(VI)착물과 함께 질량분석을 행하여 비교 검토하였다. 옥소몰리브덴(V) 착물은 비전해질이고 몰리브덴-산소의 신축진동은 $940cm^{-1}$ 부근에서 강한 흡수띠가 나타나고 결정장전이와 전하이동 전이가 일어났다. 질량분석 결과로 Mo(V, VI)착물에서 몰리브덴과 리간드의 조성이 1:2임을 확인할 수 있었고 옥소몰리브덴(VI)착물에서는 1:1조성의 착물의 질량수가 나타나지만 옥소몰리브덴(V)에서는 일부만 확인되었다.

• 환경위생공학
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• 제14권3호
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• pp.116-122
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• 1999

The purpose of this study is to develop new process named "hydrogen peroxide dissolution method". This process used hydrogen peroxide, which is harmless to human body and oxidize molybdenum wire selectively.The advantages of hydrogen peroxide dissolution method were no discharge of noxious matter when dissolution of molybdenum wire which used as the center supporter, reactions occur in room temperature and easy to recover dissolved molybdenum. This study was aimed at gathering the basic data of molybdenum wire dissolution-recovery process and proposes the reaction condition of molybdenum wire dissolution-recovery process and the factors influencing those reactions. The results were as follows:1. In the dissolution of molybdenum wire, the early condition of reaction was $15^{\circ}C$, and the temperature condition of state was $32^{\circ}C$. 2. 1) In the GSL-60W type, P.W.(Piece weight) was 11.89mg, C.R. was $65.6\Omega$. 2) In the FL-20W type, P.W. was 11.60mg, C.R. was $4.6\Omega$. 3. The molybdenum of process water was treated of a precipitation after dry and after stagnation in the one day, the molybdenum of upper water was treated of precipitation after dry and after congelation.

• 환경위생공학
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• 제14권2호
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• pp.1-7
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• 1999

In the tungsten industry as light source material, tungsten filament which used as light source material ould form after molybdenum wire which used as the center supporter for coil shape tungsten wire was removed. The purpose of this study is to develop new process named "hydrogen peroxide dissolution method". This process uses hydrogen peroxide, which is harmless to human body and oxidize molybdenum wire selectively. The results were as follows:1. The dissolution of molybdenum wire was proportion to a solution and contact surface of molybdenum wire. 2. The optimum $H_2O_2/H_2O$ were 1:0.5 ~ 1:1.75. 3. The time of dissolution was 65~70 minutes, and the PCS of sample were 20,800 PCS(1,820g). 4. Total cost($H_2O_2$, catalyst) was ￦19,088.

• 대한금속재료학회지
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• 제50권6호
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• pp.445-448
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• 2012

We studied the effect of temperature and reaction time by investigating the various temperatures and reaction times in the reduction of molybdenum oxide ($MoO_3$) to molybdenum (Mo) powder in hydrogen gas. We also studied the effect of the reaction of reduction according to the various hydrogen gas flow rates. We surveyed the reduction from molybdenum oxide to molybdenum powder in hydrogen gas and checked two temperature ranges, one from $400^{\circ}C$ to $600^{\circ}C$ and the other from $700^{\circ}C$ to $900^{\circ}C$. We found that the reaction ratio of molybdenum oxide increased with an increasing temperature and also increased with an increasing reaction time, but hydrogen gas did not influence the reduction ratio of molybdenum oxide. We examined molybdenum powders fabricated by ball milling for two hours, using with X-ray diffraction (XRD) and a scanning electron microscopy (SEM).

• 환경위생공학
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• 제18권2호
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• pp.60-66
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• 2003

This study was carried out to elucidate the preventive mechanism of molybdenum on lead-induced neuropathy, An animal model of lead neuropathy was induced by feeding diet containing lead to Sprague-Dawley rat for three weeks. Four weeks aged Sprague-Dawley rats were divided into four groups : normal control group, 10ppm-lead treated group, 1mg/kg-molybdenum treated group, 10ppm-lead and 1mg/kg-molybdenum treated group. The parameters on neuropathy were examined by measuring concentration of myo-inositol and myo-inosito uptake in sciatic nerve. In the lead-treated rats, myo-inositol concentration and myo-inositol uptake rate were reduced by from 54% to 33% respectively. This deficit results from that myo-inositol uptake system which is carrier mediated and sodium-potassium dependent was inhibited by the lead treatment. However, the molybdenum administration significantly eliminated the impairment and maintained myo-inositol concentration to about 82% of normal level. These results suggest that lead-induced neurotoxicity was significantly reduced by administration of molybdenum and the mechanism might be partly normalization of myo-inositol uptake system in sciatic nerve.

• 복식문화연구
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• 제30권1호
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• pp.88-101
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• 2022

Molybdenum is used in electrical contacts, industrial motors, and transportation materials due to its remarkable ability to resist heat and corrosion. It is also used to flame coat other metals. This study investigated, the thermal characteristics of the molybdenum sputtered material, such as electrical conductivity, and stealth effects on infrared thermal imaging cameras. To this end, molybdenum sputtered samples were prepared by varying the density of the base sample and the type of base materials used. Thereafter, the produced samples were evaluated for their surface state, electrical conductivity, electromagnetic field characteristics, thermal characteristics, stealth effect on infrared thermal imaging cameras, and moisture characteristics. As a result of infrared thermal imaging, the molybdenum layer was directed towards the outside air, and when the sample was a film, it demonstrated a greater stealth effect than the fabric. When the molybdenum layer was directed to the outside air, all of the molybdenum sputtering-treated samples exhibited a lower surface temperature than the "untreated sample." In addition, as a result of confirming electrical properties following the molybdenum sputtering treatment, it was determined that the film exhibited better electrical conductivity than the fabric. All samples that were subjected to molybdenum sputtering exhibited significantly reduced electromagnetic and IR transmission. As a result, the stealth effect on infrared thermal imaging cameras is considered to be a better way of interpreting heat transfer than infrared transmission. These results are expected to have future applications in high-performance smartwear, military uniforms, and medical wear.