• Journal of Korea Foundry Society
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• v.30 no.2
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• pp.66-75
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• 2010

The effects of alloying elements on the mechanical properties of normalized and quenched 3.60wt%C-2.60wt%C ductile cast iron poured into shell stack mold were investigated. The strength and hardness of as-cast specimen were increased and the elongation of it was decreased with the additions of Mn, Cu and Sn. The strength and hardness were increased with the addition of 0.40wt%Mo and then rather decreased with the increased addition of 0.80wt%. The strength and hardness were increased with normalizing treatment and the strengths of normalized specimens were increased slightly with the addition of alloying elements except Mo. Meanwhile the yield strength of the normalized specimen was increased slightly with the addition of Mo, the tensile strength was not changed much. Meanwhile the hardness and strength of the quenched specimen were slightly increased with the addition of Mn, those were almost not changed with the amount added. The tensile strength of the quenched specimen with larger diameter, when the Cu had been added, and the tensile and yield strengths of them, when Mo had been added, were increased with the addition of alloying element. On the other hand, those were not changed with the amount added. For the case of specimen with smaller diameter, there were no effects of these two elements. When Sn had been added, the strength of hardened specimen with larger diameter was slightly increased with the amount added. However, that with smaller diameter was rather decreased with it. The effect of specimen diameter on the strength of quenched specimen with the addition of Cu, Mo and Sn was reduced.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5703-5707
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• 2015

Background: Medicinal plants, especially examples rich in polyphenolic compounds, have been suggested to be chemopreventive on account of their antioxidative properties. Melissa officinalis L. (MO), an aromatic and medicinal plant, is well known in thios context. However, toxicity against cancer cells has not been fully studied. Here, we investigated the selective anticancer effects of an MO extract (MOE) in different human cancer cells. Materials and Methods: a hydro-alcoholic extract of MO was prepared and total phenolic content (TPC) and total flavonoid content (TFC) were determined by colorimetric assays. Antioxidant activity was determined by DPPH radical scavenging activity. MTT assays were used to evaluate cytotoxicity of different doses of MOE (0, 5, 20, 100, 250, 500, $1000{\mu}g/ml$) towards A549 (lung non small cell cancer cells), MCF-7 (breast adenocarcinoma), SKOV3 (ovarian cancer cells), and PC-3 (prostate adenocarcinoma) cells. Results: Significant (P<0.01) or very significant (P<0.0001) differences were observed in comparison to negative controls at all tested doses ($5-1000{\mu}g/ml$). In all cancer cells, MOE reduced the cell viability to values below 33%, even at the lowest doses. In all cases, $IC_{50}$ values were below $5{\mu}g/ml$. The mean growth inhibition was 73.1%, 86.7%, 79.9% and 77.8% in SKOV3, MCF-7 and PC-3 and A549 cells, respectively. Conclusions: Our results indicate that a hydro-alcoholic extract of MO possess a high potency to inhibit proliferation of different tumor cells in a dose independent manner, suggesting that an optimal biological dose is more important than a maximally tolerated one. Moreover, the antiprolifreative effect of MO seems to be tumor type specific, as hormone dependant cancers were more sensitive to antitumoral effects of MOE.

• Tribology and Lubricants
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• v.12 no.3
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• pp.107-114
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• 1996

MoS$_{2}$ bonded film was applied to reduction gears, and its lubricating properties were experimentally evaluated in terms of the power transmission efficiency and the frictional noise with a dynamo-typed gear test rig. Tests were performed in both oil lubrication and dry condition where the rotating velocity and loading torque were varied. In dry condition, MoS$_{2}$ bonded films effected the power transmission efficiency to increase about 5%, and the frictional noise level to decrease about 6 dB under the test operating conditions. It well proved that MoS$_{2}$ bonded films were a very effective solid lubricant for reduction gears. In oil lubricating conditions, the frictional properties of the coated gears were mainly governed by the lubricating oil, and lubricating effects of MoS2 bonded films were not evident. The result suggested that lubricating effect of MoS$_{2}$ bonded films would be limited to prevent a damage of reduction gears in the initial run when they were used in oil lubrication conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.303-308
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• 1994

The finite element method has been used to model and analyze the heat transfer phenomena during manufacturing process of MoSi $_{2}$ by SHS. For this urpose nonlinear transient heat transfer analyses by using ANSYS have been performed to compute the temperature distributiuon and the peak temperature in the test specimen. The effects of manufacturing process parameters such as a pre-heating temperature, the velocity of reaction zone have also been investigated. The results of the analysis have been compared with the experimental results.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.2
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• pp.105-107
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• 2005

A field study was conducted to investigate and ascertain the effects of boron and molybdenum with recommended N P K S Zn fertilizers (RFD) for sustained sugarcane yield in the sandy acidic soil in Old Himalayan Piedmont Plain of Bangladesh. Results revealed that the treatment $T_7$ having recommended fertilizers of N 120, P 35, K 100, S 25 and Zn 2kg $ha^{-1}$ + B 2kg $ha^{-1}$ + Mo 2 kg $ha^{-1}$ produced significantly higher number of millable cane (126.96\times10^3\;ha^{-1})$ except in $T_9$ with RFD + B 2 kg $ha^{-1}$ + Mo 4kg $ha^{-1}$, and higher cane yield (92.83 Mg $ha^{-1}$) among all except in $T_3$ with RFD + B2 kg $ha^{-1}$, $T_5$ with RFD + Mo 2kg $ha^{-1}$ and $T_9$ where the effects were statistically identical. The increase in cane yield by $T_7$ was $164.6\%$ over control. The treatment $T_7$ having RFD + B 2kg $ha^{-1}$ + Mo 2kg $ha^{-1}$ further gave the highest additional net economic benefit of Taka 16, 500.00 for added Band Mo at 2kg $ha^{-1}$ among all the treatments in the study.

• Corrosion Science and Technology
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• v.5 no.6
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• pp.189-195
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• 2006

Effects of tungsten (W) on the precipitation kinetics of secondary phases and the associated resistance to pitting corrosion of 25%Cr duplex stainless steels were investigated through microstructural and electrochemical noise analyses. With the partial substitution of W for Mo in duplex stainless steel, the potential and current noises of the alloy were significantly decreased in chloride solution due to retardation of the ${\sigma}$ phase precipitation. The preferential precipitation of the $\chi$ phase in the W-containing alloy during the early period of aging contributed to retarding the precipitation of the $\sigma$ phase by depleting W and Mo along grain boundaries. In addition, the retardation of the nucleation and growth of the $\sigma$ phase in the W-containing alloy appears to be attributed to the inherently low diffusivity of W compared with that of Mo.

• Journal of the Korean institute of surface engineering
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• v.37 no.2
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• pp.128-136
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• 2004

Effects of alloying elements on the surface characteristics of Fe-38Al intermetallic compounds were investigated using potentiostat. The specimens were casted by the vacuum arc melting. The subsequent homogenization and the stabilization led to the homogeneous DO$_3$ structure of the specimen. After the corrosion tests, the surface of the tested specimen was observed by the optical microscopy and scanning electron microscopy(SEM). For Fe-38 at.% Al intermetallic compound, the addition of Cr and Mo proved to be beneficial in decreasing the grain boundary attack by decreasing the active current density. Addition of Band Nb resulted in a higher active current density and also a higher passive current density. These results indicated the role of Cr and Mo in improving the pitting corrosion resistance of Fe-38 at.%Al intermetallic compound. Band Nb addition to Fe-38 at.%Al accelerated the granular corrosion. Fe-38 at.%Al containing Cr and Mo showed remarkably improved pitting corrosion resistance in comparison with Band Nb addition to Fe-38 at. %Al.

• Corrosion Science and Technology
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• v.2 no.1
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• pp.12-17
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• 2003

The effects of Cr content and film formation potential on electronic behaviors of the passive film on Fe-Cr alloys were investigated in borate buffer solution. Influence of pH on passive films of both Fe-Cr and Fe-Cr-Mo alloys was also investigated. Mott-Schottky and cyclic voltammetry techniques were used to elucidate electronic behaviors of passive films and their electrochemical characteristics. AES analysis of passive films was carried out. Results showed that doping density decreased as Cr content and film formation potentials increased. The addition of Mo to Fe-Cr alloy had little influence on donor densities in pH 9.2 solution but some effects on the decrease in donor densities in pH 1.6 acidic solution.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.11
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• pp.2837-2845
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• 1994

Several methods have been developed to predict on the remaining life of the old power plants. However, Larson-Miller parameter, one of existing creep life prediction methods, has not reflected the effect of material degradatioin and grain size. So this study has been carried out to research the effects of material degradation and austenite grain coarsening on the life prediction of 3.5Ni-Cr-Mo-V steel. An experimental result shows that carbide coarsening has no significant effects on the creep rupture life and the Larson-Miller parameter, but grain coarsening has an important influence on the creep ruptrure life and the Larson-Miller parameter. Therefore Larson-Miller constant, K should be determined to consider on the chemical composition and the grain size of materials.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.05a
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• pp.34-35
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• 1999