• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.37.1-37.1
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• 2009

몰리브덴 금속박막(Metal Mo)은 우수한 전기전도도로 인해 $CuInSe_2$로 대표되는 I-III-$VI_2$족 화합물 반도체 박막태양전지에서 후면전극으로 널리 이용되고 있는 재료로서 일반적인 증착방법으로CVD, PVD, Thermal evaporation, Sol-gel 등이 있으며, 이중에서 Sputtering에 의한 증착법이 주로 사용되고 있다. 이에 본 연구에서는 $MoO_3$분말의 수소 환원 과정 중에 발생하는 기상인 $MoO_3(OH)_2$ 기상의 화학증기수송(CVT)를 이용하여 $MoO_x$ 박막을 증착하고 다시 수소분위기에서 수소 환원하는 증착법을 통해 균일하고 부착성이우수한 Mo 박막을 제조 하였다. $550^{\circ}C$, 60min의 유지시간에서 약 900nm의 균일한 $MoO_x$ 박막을 증착하였으며, $650^{\circ}C$, 15min 의 환원조건에서 모두 금속 몰리브덴 박막으로 상변화 함을 XRD와 SEM을 통해 확인하였다. 본 연구에서 사용된 화학증기수송에 의한 박막 증착은 기존의 공정에 비해 매우 저렴하며, 반응중에 유해하지 않은 부산물로 인해 환경 친화적이며 또한 대형화가 가능한 공정으로 많은 응용이 기대된다.

• Journal of the Korean Chemical Society
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• v.34 no.2
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• pp.171-178
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• 1990

The rates of the reaction Of $[MoO_2(S_2CNC_4H_8)_2]$ with triphenylphosphine in 1,2-dichloroethane have been by the spectrophotometric method. The increase in absorbance at 514 nm has been interpreted as a result of production of $[Mo_2O_3(S_2CNC_4H_8)_4]$ and the decrease in absorbance then corresponds to the reduction of $[Mo_2O_3(S_2CNC_4H_8)_4]$. The data suggest mechanisms involving the formation of $\mu$-oxo dimer in the first stage and molybdenum(IV) in the second stage.

• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.391-396
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• 2007

The three-dimensional structure of an inorganic crystal, CaMoO4 (space group I 41/a, a = 5.198(69) A and c = 11.458(41) A), was determined by electron crystallography utilizing a high voltage electron microscope. An initial structure of CaMoO4 was determined with 3-D electron diffraction patterns. This structure was refined by crystallographic image processing of high resolution TEM images. X-ray crystallography of the same material was performed to evaluate the accuracy of the TEM structure determination. The cell parameters of CaMoO4 determined by electron crystallography coincide with the X-ray crystallography result to within 0.033-0.040 A, while the atomic coordinates were determined to within 0.072 A.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.198-203
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• 1995

The Mo(V) $di-\mu-oxo$ type $(Mo_2O_4(H_2O)_2L)$ complexes $(L:\;C_3H_7CH(SCH_2COOH)_2,\;C_6H_5CH(SCH_2COOH)_2,\;CH_3OC_6H_4CH(SCH_2COOH)_2,\;C_5H_{10}C(SCH_2COOH)_2,\;C_3H_7C(CH_3)(SCH_2COOH)_2,\;C_3H_7CH(SCH_2CH_2COOH)_2,\;C_6H_5CH(SCH_2CH_2COOH)_2)$ have been prepared by the reaction of $[Mo_2O_4(H_2O)_6]^{2+}$ with a series of dithiodicarboxy ligands. These complexes are completed by two terminal oxygens arranged trans to one another and each ligand forms a chelate type between two molybdenum. In $Mo_2O_4(H_2O)_2L$, two $H_2O$ coordinated at trans site of terminal oxygens. The prepared complexes have been characterized by elemental analysis, infrared spectra, electronic spectra, and nuclear magnetic resonance spectra. In the potential range -0.00 V to -1.00 V at a scan rate of 20 $mVs^{-1}$, a cathodic peak at -0.50∼-0.58 V (vs. SCE) and an anodic peak at -0.40∼-0.43 V (vs. SCE) have been observed in aquous solution. The ratio of the cathodic to anodic current ($I_{pc}/I_{pa}$) is almost 1, we infer that redox is reversible reaction.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1218-1224
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• 2023

We investigated the radiation shielding competence for TeO₂-V₂O₅-MoO₃ glasses. The Phy-X software was used to report the radiation shielding parameters for the present glasses. With an increase in TeO₂ and MoO₃ content, the samples' linear attenuation coefficient improves. However, at low energies, this change is more apparent. At low energy, the present samples have an effective atomic number (Z_eff) that is relatively high (in order of 16.17-24.48 at 0.347 MeV). In addition, the findings demonstrated that the density of the samples is a very critical factor in determining the half value layer (HVL). The minimal HVL for each sample can be found at 0.347 MeV and corresponds to 1.776, 1.519, 1.391, 1.210 and 1.167 cm for Te1 to Te5 respectively. However, the highest HVL of these glasses is recorded at 1.33 MeV, which corresponds to 3.773, 3.365, 3.218, 2.925 and 2.908 cm respectively. The tenth value layer results indicate that the thickness of the specimens needs to be increased in order to shield the photons that have a greater energy. Also, the TVL results demonstrated that the sample with the greatest TeO₂ and MoO₃ concentration has a higher capacity to attenuate photons.

• Applied Chemistry for Engineering
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• v.2 no.2
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• pp.127-137
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• 1991

The dissociation and partial oxidation of $CH_3OH$ on polycrystalline $MoO_3$ powder catalyst were studied using thermal desorption spectrometry(TDS) under high vacuum condition. $CH_3OH$ was dissociatively adsorbed on $MoO_3$ in the forms of surface methoxy($-OCH_3$) and atomic hydrogen(-H). $CH_3OH$ desorbed at 425 K via the re-association of methoxy and adsorbed hydrogen atom, and HCHO desorbed at 545 K through the bond breakage of C-H in methoxy. Water TDS spectra showed two desorption peaks, that is, ${\alpha}$-peak at 428 K and ${\beta}$-peak at 586 K. It was suggested that ${\alpha}$-peak was due to the hydroxyl formed on $MoO_3$ surface during the dissociation of $CH_3OH$, and that ${\beta}$-peak was from the association of lattice oxygen and surface hydrogen atom formed by the bond breakage of C-H in methoxy. Pre-adsorbed oxygen on the surface of $MoO_3$ catalyst increased the amount of adsorption of $CH_3OH$ by promoting the dissociation of $CH_3OH$ on the surface, whereas pre-adsorbed water decreased the amount of adsorption of $CH_3OH$ by blocking of adsorption sites for $CH_3OH$.

• Journal of the Korean Vacuum Society
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• v.9 no.3
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• pp.263-266
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• 2000

This paper is focused on the fabrication of reliable Al/$TiO_2-SiO_2$/Mo antifuse, which could operate at low voltage along with the improvement in on/off state properties. Mo metal as the bottom electrode had smooth surface and high melting point, and was being kept as-deposited $SiO_2$film stable. The breakdown voltage of TiO_2-SiO_2$ stacked antifuse was better than that of same-thickness (100 $\AA$) $SiO_2$antifuse because of Ti diffusion in $SiO_2$. The improving breakdown-voltage and on-resistance can be obtained as well as the influence of hillock in the bottom metal is reduced by using double insulator. Low on-resistance (65 $\Omega$) and low programming voltage (9.0 V) can be obtained in these antifuses with 250 $\AA$ double insulator.

• Korean Journal of Materials Research
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• v.4 no.6
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• pp.669-680
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• 1994

Oxidation behaviour of TiAl intermetallic compounds with the addition of Cr, V, Si, Mo, or Nb was investigated at 900~$1100^{\circ}C$ under the atmospheric environment. The reaction products were examined by XRD, SEM equipped with WDX. The weight gain by continuous oxidation increased with the addition of Cr or V, but there was less weight gain when Mo, Si or Nb was added individually. he oxidation rate of Cr- or V-added TiAl was always larger than that of TiAI. However, oxidation rate of Si-, Mo- or Nb-added TiAl was almost same or smaller than that of TiAI. Thus, it is concluded that the addition of Cr or V did not improve the oxidation resistance, whereas the addition of Si, Mo or Nb improved the oxidation resistance. Oxides formed on TiAl with Mo, Si, and Nb were found to be more protective, resulting from the decrease in diffusion rate of the alloying elements and oxygen. Nb strengthened the tendency to form $AI_{2}O_{3}$ in the early stage of oxidation, due to the continuous $AI_{2}O_{3}$ layer formation and dense $Tio_{2}+AI_{2}O_{3}$ layer. According to the Pt-marker test of TiAI- 5wt%Nb, oxygen diffused mainly inward while oxides were formed on the substrate surface. Upon thermal cyclic oxidation at $900^{\circ}C$, it is shown that the addition of Cr or Nb improved the adherence of oxide scale to the substrate.

• Journal of Bio-Environment Control
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• v.16 no.2
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• pp.151-156
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• 2007

This work was conducted to investigate the important rooting factors through comparative analysis of a physiological differentiation after layering treatment using four apple rootstocks of different rooting abilities; M.26, M.9, O.3, and Mo.84. Mo.84 showed the highest rooting rate in from rootstocks, while O.3 was the lowest. Mo.84 also found to have the highest indole-3-acetic acid (IAA) content, although the fluctuation of IAA contents was not consistent with layering treatment. In contrast, abscisic acid (ABA) content of Mo.84 which showed highest rooting was lowest among rootstocks regardless of layering treatment. And ABA contents of all rootstocks were decreased after layering treatment than before layering treatment. O.3 which showed poor rooting rate revealed lowest in boron content. Carbohydrate/nitrogen (C/N) ratio of Mo.84 was the highest in all rootstocks. Therefor, we assumed that he IAA contents in layering treated rootstocks were not seemed to be a major rooting factor, but the changes in ABA contents and boron levels limit rooting in dwarf apple rootstocks.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.93-96
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• 2000

In this study, we investigated the electromagnetic properties of Mn-Zn ferrite doped with rare earth oxide (Dy$_2$O$_3$, Er$_2$O$_3$). The main composition is 52mo1% $\alpha$-Fe$_2$O$_3$, 25mo1% Mn$_3$O$_4$23mo1% ZnO and doped with them(0.05wt%~0.25wt%, step:0.05wt%). An experimental process has advanced by conventional ferrimagnetism manufacturing that was prepared by standard ceramic techniques. The XRD pattern of all doped sample were observed spinel and secondary phase. The density of sample were measured nearly constant value. As increased the additive, resistivity, initial permeability and real component of the series complex permeability increased with setting limits each other. In case of Mn-Zn ferrite excess doped with them, resistivity, initial permeability and real component of the series complex permeability decreased and magnetic loss increased in proportion to increasing the additive.