• Journal of radiological science and technology
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• v.37 no.4
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• pp.239-246
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• 2014

Filter absorbs low-energy X-ray to increase the average energy and reduces patient exposure dose. This study investigates if the materials of Mo and W could be used for the digital imaging device CR by conducting image assessment and dose measurement of SNR, FOM and histogram. In addition, measurement of beam quality was conducted depending on the material of the filter, and at the same time, a proper combination of filters was examined depending on the change in tube voltage (kVp). In regard to entrance skin dose, Mo filter showed the dose reduction by 42~56%, compared to Cu filter. Moreover, Mo filter showed higher transmission dose by around 1.5 times than that of Cu filter. In image assessment, it was found that W was unsuitable to be used as a filter, whereas Mo could be used as a filter to reduce dose without decline in image quality at the tube voltage of 80 kVp or higher. As tube voltage increased, 2.0 mm Al+0.1 mm Mo almost had a similar histogram width to that of 2.0 mm Al+0.2 mm Cu. Therefore, Mo filter can be used at relatively high tube voltage of 80 kVp, 100 kVp and 120 kVp. The SNR of 2.0 mm Al+0.1 mm Mo did not show any significant difference from those of 2.0 mm Al+0.2 mm Cu and 2.0 mm Al+0.1 mm Cu. As a result, if Mo filter is used to replace Cu filter in general radiography, where 80 kVp or higher is used for digital radiation image, patient exposure dose can be reduced significantly without decline in image quality, compared to Cu filter. Therefore, it is believed that Mo filter can be applied to chest X-ray and high tube voltage X-ray in actual clinical practice.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.2
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• pp.93-104
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• 2004

This pot experiment was conducted to investigate the effects of combined micronutrient application($T_1$; control, $T_2$; Fe, $T_3$; Fe+Mn, $T_4$; Fe+Mn+Cu, $T_5$ ; Fe+Mn+Cu+Zn, $T_6$ ; Fe+Mn+Cu+Zn+Mo, T$_{7}$; Fe+Mn+Cu+Zn + Mo + B) on forage performance of pure and mixed cultures of orchardgrass and white clover. The fifth part was concerned with the changes in the total and relative contents, uptake amounts, and mutual ratios. of micronutrients in forages. The results obtained are summarized as follows: 1. The relative contents(total contents of 6 micronutrients = 100%) of Fe and Mn were considerably influenced by the antagonism between Fe and Mn, and also were influenced by the differences in Mn-absorption between orchardgrass and white clover. Compared with pure culture, orchardgrass showed high relative contents of Mn, and low relative contents of Fe and B in mixed culture. White clover, however, tended to be exactly opposed to the above trends. In relative contents, the T$_6$ 6/ resulted generally in decrease of Fe. However the $T_7$ resulted in increase of Mn and B. In addition, the $T_7$ resulted in decrease of Cu and Zn in orchardgrass, and Mo in white clover. 2. In general, there were differences in the tendency between the yield changes and the uptake amounts of micronutrients. General differences have been showed in the uptake amounts and mutual ratios of micronutrients based on the forage species, pure/mixed culture, additional fertilization, and antagonism. The uptake amounts of total micronutrients were generally increased by the treatments with increased combination. In uptake amounts, the $T_7$ resulted in the increase of Mn and B, and decrease of Mo. 3. The mutual ratios of Fe/Mn, Fe/Cu, and Mn/Cu were considerably influenced by the antagonism between Fe and Mn. At the $T_7$ , very low ratio of Fe/Mo affected by the T6 tended to be somewhat improved because of the decrease of Mo content． The poor growth of forages at the $T_6$ was improved by the $T_7$ . This fact was likely to be caused by the adequate B/Mo ratio.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.530-537
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• 1995

The neutral complexes $MCl_3(phda)(MeCN)]$ and $[MCl_3(PPh_3)_2(MeCN)]$ (M=Mo, V) were prepared by the reaction of $MCl_z$, (M=Mo; z=5, M=V; z=3) with N, P-donating ligands in acetonitrile solution. Addition of AgClO_4$ to these neutral monomeric complexes in acetone solution afforded $MCl_{3-n}L_2(MeCN)(S)_n](ClO_4)_n$ (n=1, 2 : s=solvent). Two types of asymmetrical homo- and hetero-dinuclear complexes have been synthesized. The type of chloride bridged dinuclear complex is $[(MeCN)(phda)ClM({\mu}-Cl)_2M'Cl(PPh_3)_2(MeCN)](ClO_4)_2.$ And the type of pyrazine bridged complex is $[(MeCN)(phda)Cl_2M({\mu}-pyz)M'Cl_2(PPh_3)_2(MeCN)](ClO_4)_2.$ These complexes were characterized by elemental analysis, $^1H,\;^13C$ NMR, IR, Far-IR and UV-Vis spectroscopy.

• Journal of the Korean Chemical Society
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• v.38 no.11
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• pp.808-818
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• 1994

The neutral compounds [$MCl_3L_2$(MeCN)] (M = Mo, V: L = $PPh_3$, 1/2 phda) have been prepared from the reaction of starting material $MCl_z$ (M = Mo; z = 5, M = V; z = 3) with N,P-donating ligands in acetonitrile solution. Addition of $AgClO_4$ to these neutral monomeric compounds in acetone solution were produced [$MCl_3-_nL_2(MeCN)(S)_n$]$(ClO_4)_n$ (n = 1, 2 : s = solvent). Finally treatment of bivalent cationic compound and neutral compound was formed chloride bridged dinuclear complex $[(MeCN)(L)_2ClM({\mu}-Cl)_2M'Cl(L)_2(MeCN)](ClO_4)_2$ and treatment of univalent cationic compound with half equivalent pyrazine to pyrazine bridged complex $[(MeCN)(L)_2Cl_2M({\mu}-pyz)M'Cl_2(L)_2(MeCN)](ClO_4)_2$. These complexes are characterized by elemental analysis, $^1H$, $^{13}C$ NMR, IR, Far-IR and UV-Vis spectroscopy.

• Korean Journal of Materials Research
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• v.23 no.2
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• pp.135-142
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• 2013

The Ti-6Al-4V extra low interstitial (ELI) alloy has been widely used as an orthopedic implant material because of its excellent mechanical properties and biocompatibility. However, it still has many problems, including a high elastic modulus and toxicity of the Al and V elements. Therefore, non-toxic biomaterials with a low elastic modulus need to be developed. A high energy mechanical milling (HEMM) process is introduced to improve the effect of sintering. Rapid sintering of spark plasma sintering (SPS) under pressure was used to make an ultra fine grain of Ti-25 wt.%Nb-7 wt.%Zr-10 wt.%Mo-(10 wt.%CPP) composites with bio-attractive elements for increasing strength. These composites were fabricated by SPS at $1000^{\circ}C$ at 60 MPa using HEMM powders. During the sintering process, $CaTiO_3$, TixOy, and CaO were formed because of the reaction between Ti and CPP. The effects of CPP content on the physical and mechanical properties of the sintered Ti-Nb-Zr-Mo-CPP composites were investigated. The biocompatibility and corrosion resistance of the Ti-Nb-Zr-Mo alloys were improved by the addition of CPP.

• Corrosion Science and Technology
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• v.9 no.1
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• pp.20-28
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• 2010

According to the bipolar model, ion selectivity of some species in the passive film is important factor to control the passivation. An increase of cation selectivity of outer layer of the passive film can stabilize the film and improves the corrosion resistance. Therefore, the formation and roles of ionic species in the passive film should be elucidated. In this work, two types of solution (hydrochloric or sulfuric acid) were used to test high N and Mo-bearing stainless steels. The objective of this work was to investigate the formation of oxyanions in the passive film and the roles of oxyanions in passivation of stainless steel. Nitrogen exists as atomic nitrogen, nitric oxide, nitro-oxyanions (${NO_x}^-$), and N-H species, not nitride in the passive film. Because of its high mobility, the enriched atomic nitrogen can act as a reservoir. The formation of N-H species buffers the film pH and facilitates the formation of oxyanions in the film. ${NO_x}^-$ species improve the cation selectivity of the film, increasing the oxide content and film density. ${NO_x}^-$ acts similar to a strong inhibitor both in the passive film and at active sites. This facilitates the formation of chromium oxide. Also, ${NO_x}^-$ can make more molybdate and nitric oxide by reacting with Mo. The role of Mo addition on the passivation characteristics of stainless steel may differ with the test environment. Mo exists as metallic molybdenum, molybdenum oxide, and molybdate and the latter facilitates the oxide formation. When nitrogen and molybdenum coexist in stainless steel, corrosion resistance in chloride solutions is drastically increased. This synergistic effect of N and Mo in a chloride solution is mainly due to the formation of nitro-oxyanions and molybdate ion. Oxyanions can be formed by a 'solid state reaction' in the passive film, resulting in the formation of more molybdate and nitric oxide. These oxyanions improve the cation selectivity of the outer layer and form more oxide and increase the amount of chromium oxide and the ratio of $Cr_2O_3/Cr(OH)_3$ and make the film stable and dense.

• The Journal of Advanced Prosthodontics
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• v.14 no.1
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• pp.32-44
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• 2022

PURPOSE. Mandibular flexure is a crucial phenomenon that may affect the success of rigid bilateral mandibular prosthetic treatment. The aim of this study was to determine the amount of median mandibular flexure (MMF) that occurs during mouth opening from anterior to posterior mandible in seven different regions, in different age and gender groups of both dentulous and edentulous subjects, using an intraoral digital scanner. MATERIALS AND METHODS. In this study, the mandibular arch of 56 dentulous and 35 edentulous individuals were scanned with an intraoral scanner at both the minimum mouth opening (MnMO) and the maximum mouth opening (MxMO). MMF values were calculated by subtracting the distance value at the MxMO from the distance between the reference points at the MnMO at seven different mandibular regions of dentulous and edentulous subjects. In addition, the left and right side MMF values were measured. All data were analyzed statistically (α = .05). RESULTS. MMF value increased linearly from anterior to posterior mandible in both dentulous and edentulous individuals. The differences in MMF values were not statistically significant according to side (left/right), age, or gender (P > .05). No significant differences were found between the mean MMF values of the same region in both dentulous and edentulous individuals (P > .05). CONCLUSION. MMF was seen in different regions of the mandibles of both edentulous and dentulous individuals measured at the MxMO. Mandibular flexure should be considered for the success and prognosis of the long-span and rigid prostheses.

• Journal of the Korean institute of surface engineering
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• v.56 no.2
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• pp.160-168
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• 2023

Recently, investigation on metallization is a key for a stretchable display. Amorphous metal such as Ni and Zr based amorphous metal compounds are introduced for a suitable material with superelastic property under certain stress condition. However, Ni and Zr based amorphous metals have too high resistivity for a display device's interconnectors. In addition, these metals are not suitable for display process chemicals. Therefore, we choose an aluminum based amprhous metal Al-Mo as a interconnector of stretchable display. In this paper, Amorphous Forming Composition Range (AFCR) for Al-Mo alloys are calculated by Midema's model, which is between 0.1 and 0.25 molybdenum, as confirmed by X-ray diffraction (XRD). The elongation tests revealed that amorphous Al-20Mo alloy thin films exhibit superior stretchability compared to pure Al thin films, with significantly less increase in resistivity at a 10% strain. This excellent resistance to hillock formation in the Al20Mo alloy is attributed to the recessed diffusion of aluminum atoms in the amorphous phase, rather than in the crystalline phase, as well as stress distribution and relaxation in the aluminum alloy. Furthermore, according to the AES depth profile analysis, the amorphous Al-Mo alloys are completely compatible with existing etching processes. The alloys exhibit fast etch rates, with a reasonable oxide layer thickness of 10 nm, and there is no diffusion of oxides in the matrix. This compatibility with existing etching processes is an important advantage for the industrial production of stretchable displays.

• Journal of Electrochemical Science and Technology
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• v.15 no.1
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• pp.67-95
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• 2024

Direct alcohol fuel cells (DAFCs) have gained much attention as promising energy conversion devices due to their ability to utilize alcohol as a fuel source. In this regard, Molybdenum-based electrocatalysts (Mo-ECs) have emerged as a substitution for expensive Pt and Ru-based co-catalyst electrode materials in DAFCs, owing to their unique electrochemical properties useful for alcohol oxidation. The catalytic activity of Mo-ECs displays an increase in alcohol oxidation current density by several folds to 1000-2000 mA mg_Pt^-1, compared to commercial Pt and PtRu catalysts of 10-100 mA mg_Pt^-1. In addition, the methanol oxidation peak and onset potential have been significantly reduced by 100-200 mV and 0.5-0.6 V, respectively. The performance of Mo-ECs in both acidic and alkaline media has shown the potential to significantly reduce the Pt loading. This review aims to provide a comprehensive overview of the bifunctional mechanism involved in the oxidation of alcohols and factors affecting the electrocatalytic oxidation of alcohol, such as synthesis method, structural properties, and catalytic support materials. Furthermore, the challenges and prospects of Mo-ECs for DAFCs anode materials are discussed. This in-depth review serves as valuable insight toward enhancing the performance and efficiency of DAFC by employing Mo-ECs.

• Journal of Mushroom
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• v.2 no.3
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• pp.163-167
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• 2004

It shows that there is the fastest growth of S. crispa in the weak acid pH5. Also, it shows that S. crispa has the best environment in the MEF media. The next desirable one was as in this array: MES, MEI, YMF, YMM, YMT, YMB, YMI, MEA, PDA. The best fungi-growth of S. crispa is shown within the 0.2% addition of multi-mineral. The slow fungi-growth of S. crispa is shown within as the opposite. The phisical growth of S. crispa has a absolute need of comparatably large amount of P,K,N,S etc as inorganic minerals. In addition of that, as a minor element, Fe, Zn, Cu, Mo, Co, Mn, Cl etc are should be included. The best fungi-growth of S. crispa is shown within the 0.1% addition of biotin. The slow fungi-growth of S. crispa is shown within as the opposite. The best fungi-growth of S. crispa is shown within the 2% addition of fructose. The slow fungi-growth of S. crispa is shown within as the opposite.