• Composites Research
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• 제16권3호
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• pp.41-48
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• 2003

본 연구에서는 고온 산화분위기 하에서 탄소/탄소 복합재료의 내산화 특성 향상을 위해 사용된 이규화 몰리브덴(MoSi$_2$)의 함량(0. 4, 12. 그리고 20 wt%)에 따른 복합재료의 충격특성에 관하여 고찰하였다. 결과로서, MoSi$_2$가 함침된 탄소/탄소 복합재료는 이를 함유하지 않은 것에 비하여 충격특성 향상의 원인이 되는 탄소섬유와 매트릭스 수지간의 계면결합력 증가를 가져왔으며, 특히 12 wt% MoSi$_2$가 현재의 시스템에서 가장 우수한 충격특성을 나타내었다. 이는 복합재료 내의 탄소섬유, 필러, 그리고 매트릭스 수지간의 계면 접착력의 증가를 가져오는 90$0^{\circ}C$ 전후에서 MoSi$_2$의 취성­연성 전이(BDT) 작용 때문이라 사료된다.

• 한국전기전자재료학회논문지
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• 제30권8호
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• pp.525-529
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• 2017

Molybdenum oxide ($MoO_3$) offers pivotal advantages for high optical transparency and low light reflection. Considering device fabrication, n-type $MoO_3$ semiconductor can spontaneously establish a junction with p-type Si. Since the energy bandgap of Si is 1.12 eV, a maximum photon wavelength of around 1,100 nm is required to initiate effective photoelectric reaction. However, the utilization of infrared photons is very limited for Si photonics. Hence, to enhance the Si photoelectric devices, we applied the wide energy bandgap $MoO_3$ (3.7 eV) top-layer onto Si. Using a large-scale production method, a wafer-scale $MoO_3$ device was fabricated with a highly crystalline structure. The $MoO_3/p-Si$ heterojunction device provides distinct photoresponses for long wavelength photons at 900 nm and 1,100 nm with extremely fast response times: rise time of 65.69 ms and fall time of 71.82 ms. We demonstrate the high-performing $MoO_3/p-Si$ infrared photodetector and provide a design scheme for the extension of Si for the utilization of long-wavelength light.

• 자원환경지질
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• 제44권2호
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• pp.109-122
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• 2011

국내 주요 몰리브덴 광상은 쥐라기 대보 조산운동기부터 후조산기인 백악기를 거쳐 제삼기까지 페그마이트형, 그라이센형, 스카른형, 반암형, 광맥형 광상과 같은 다양한 광상 유형으로 배태되고 있다. 장수 몰리브덴 광산은 쥐라기 티탄철석 계열 복운모 화강암과 관련된 페그마타이트 광상으로 배태되며, 광화 시기는 $159.6{\pm}4.5$ Ma이다. 금성 몰리브덴 광산은 분화가 매우 진행된 화강암과 관련된 스카른형/반암형 광상으로 큐폴라 광체의 광화시기는 96.5~107.5 Ma를 보이며, 황강리 광화대에 나타나는 후기 백악기 광화시기와 일치하고 있다. 연일 몰리브덴 광산은 반암형 광상으로 배태되고, 금음 몰리브덴 광산은 전단대를 따라 충진하는 석영 세맥으로 배태되며, 광화 시기는 각각 $58.4{\pm}1.6$ Ma과 $54.4{\pm}1.2$ Ma이다. 한국의 중생대 몰리브덴 광상은 조구조적 전화 특성에 따라 쥐라기에는 심부 화성활동을 반영한 페그마타이트질 맥상 광상으로 산출되는 반면, 백악기에는 천부 화성활동과 관련된 스카른형/반암형/광맥형 광상으로 배태된다. 특히 제삼기 몰리브덴 광화작용은 한반도 동해안을 따라 배태되는 제삼기 분지형성과 연계된 화성활동과 밀접한 관계를 보이고 있다.

• 대한화학회지
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• 제44권3호
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• pp.194-199
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• 2000

The chemical behavior for Mo(0) and W(0) complexes, [M(CO)$_2$(PPh$_3$)$_4$] (M=Mo and W),has been investigated by UV-vis spectroscopic, magnetic, and electrochemical methods. Three absorption bands are observed in the UV-spectra. The crystal-field-splitti ng energy, spin-pairing energy, and bond strengths were deduced from the spectra. The metal d electrons in both complexes seemed to be delocalized in low-spin state.Metal ligand correlation appeared to strongly depend on bond strengths and diamagnetic properties. In electrochemical processes, both complexes exhibit an irreversible reduction wave.

• Nuclear Engineering and Technology
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• 제31권6호
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• pp.529-540
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• 1999

As part of IAEA CRP on "Compilation and evaluation of photonuclear data for applications", we evaluated photoproduction data of Mo, Zn, S and Cl isotopes for medical use and biological applications. Available experimental data were collected and their discrepancies were analyzed to select or reconstruct the representative data set. The photoabsorption cross sections were then evaluated tv applying the Giant Dipole Resonance (GDR) model for the energies below about 30 MeV and the quasi-deuteron model for energies below 140 MeV. The resulting representative photoabsorption data were given as input for the theoretical calculations for the emission process of light nuclei including neutron, proton, deuteron, triton, $^3He$, alpha particles and gamma rays by use of the Hauser-Feshbach and the preequilibrium model.

• Tribology and Lubricants
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• 제11권1호
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• pp.50-57
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• 1995

When engine oil is used under severe running condition, the Lubricational characteristics is very important. I have studied the Lubricational characteristics with Compound Additives of engine oil for the Falex wear test machine. Adding detergent (Ca-phenate) to engine oil, the seizure is more improved than in case of non-adding, and adding Zn-DTP (Zinc dialkyl dithio phosphate), the extreme pressure property is excellent at the high load. But when the PTFE (Polytetra Fluoro Ethylene) and MoS$_{2}$ (Molybdenum disulfide) are added, the temperature characteristics and the anti-wear property become excellent because the stability can be maintained in a high temperature. The result are as follows, it can be improved that when the compound of the Ca-phenate and Zn-DTP, MoS$_{2}$, PTFE, etc. was added to engine oil, the lubrication characteristics become better. It is argued that it is improved because of excellence of the anti-wear, the extreame pressure properties and the heat stability.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1809-1812
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• 2006

In this paper, the thermally evaporated molybdenum oxide $(MoO_x)$ is investigated as the effective hole-injection material for organic lightemitting devices (OLEDs). The use of $MoO_x$ significantly lowers the operating voltage of OLEDs, insensitive to the anode materials used.

• 대한화학회지
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• 제25권3호
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• pp.177-182
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• 1981

$[MoO(NCS)_5]^{2-}$의 벤조일피리딘늄 및 루티딘늄을 합성한 후 전기전도도, 자기모멘트, 가시 및 적외선스펙트라등에 이하여 이들의 구조를 조사하였다. 옥소오이소티오시아나토몰리브덴(Ⅴ)의 벤조일피리딘늄 및 루티딘늄염에서 티오시아나토의 질소가 몰리브덴과 결합되었으며 벤조일피리딘과 루티딘은 리간드가 아닌 양이온으로 존재함을 확인하였다. 이들 착물은 d-d전이와 전하이동전이가 일어 났으며 착물의 자기모멘트는 ${mu}_{spin-only}$ 값과 거의 같았다.

• Nuclear Engineering and Technology
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• 제31권4호
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• pp.365-374
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• 1999

A nuclear design of fission moly production targets for a research reactor, HANARO was peformed. It was found that the use of MCNP-4A, ORIGEN-2 code was reliable for the analysis of production characteristics of $^{99}$ Mo in a target fuel at an irradiation holes. A parametric study was done for the optimization of target location, target dimension, target shape and fuel materials. It was shown that a fuel thickness was the most sensitive parameters and electro-deposited target gave the highest 99Mo yield ratio. A pellet target with vibro-compaction powder, however, showed the largest production capacity and better engineering feasibility even with less yield ratio. Ten kinds of optimized target design for both LEU and HEU satisfied all the given design constraints. The most favorable design was the HEU ring-shaped electro-deposited target, considered the safety limit, production yield, chemical process easiness, yield ratio, and amount of radioactive waste.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.141-142
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• 2000

In order to improve electron field emission and its stability, tip surface of amorphous silicon field emitters have been coated with molybdenum layer with a thickness of 25 nm through the gate opening and annealed rapidly in inert ambient. Compared with amorphous silicon field emitters, Mo silicidized amorphous silicon field emitters exhibited lower turn on voltage about 9 V, 3.8 times higher maximum current, 3.1 times lower fluctuation range and less change of the emission current depending on the vacuum level.