• Title/Summary/Keyword: Mo addition

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Fabrication and Optical Characterization of Highly Dy3+-ion-incorporated Alumino-borosilicate Glasses for Magneto-optical Applications at 1550 nm (1550 nm 자기광학 응용을 위한 고농도 Dy3+ 이온이 함유된 알루미노보로실리케이트 유리의 제조 및 자기광학 특성 분석)

  • Kadathala Linganna;Yong-Tak Ryu;Young-Ouk Park;Bong-Ahn Yu;Bok Hyeon Kim
    • Korean Journal of Optics and Photonics
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    • v.35 no.3
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    • pp.115-120
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    • 2024
  • Magneto-optical (MO) materials have attracted much attention, since they can be utilized for various optical applications, such as magnetic field sensors, optical current sensors, optical isolators, and optical circulators. In this study, alumino-borosilicate (ABS) glasses with high concentrations of Dy3+ ions were fabricated by a conventional melt-quenching technique, and the dependence of their thermal, optical, and magneto-optical properties on Dy3+ ion concentration was investigated. The MO property of the glasses was investigated by measurement of Faraday rotation at 1550 nm. The Faraday rotation angle increased linearly with the increase of Dy3+ ion concentration in the glasses. A very high Verdet constant of -6.86 rad/(T·m) was obtained for glass with a Dy3+ ion concentration of 30 mol%. In addition, the ABS-Dy glasses showed good thermal stability of greater than 128 ℃ against crystallization, and high optical transmission of 70% in the visible to near-infrared windows of 480-720, 1390-1560, and 1800-2400 nm. Due to the high Verdet constant and good thermal stability, the ABS-Dy glasses in this study could be candidate optical materials for MO device applications at 1550 nm.

A study on the transmission planning using OPF in CBP markets (CBP 시장에서 OPF를 활용한 송전설비계획에 관한 연구)

  • Han, Seok-Man;Kim, Kwang-Mo;Chung, Koo-Hyung;H.Kim, Bal-Ho
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.412-413
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    • 2006
  • This paper proposed the transmission planning mechanism in competitive power markets. This mechanism used Optimal Power Flow(OPF) to calculate operation cost and Contingency Constrained OPF(CC-OPF) to consider N-1 contingency outage. In addition, this algorithm deduced a yearly transmission planning using Dynamic Programming(DP).

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Deposition of Diamond Film by Hydrogen-oxyacetylen Combustion Flame

  • Ko, Chan-Kyoo;Park, Dong-Wha
    • The Korean Journal of Ceramics
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    • v.4 no.1
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    • pp.1-4
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    • 1998
  • Diamond film was deposited on Mo substrate at atmospheric pressure using combustion flame apparatus with the addition of H2. At a temperature above 100$0^{\circ}C$, parts of the film were converted into graphites and these were etched by hydrogen atoms. With increasing $C_2H_2/O_2$ ratio, the nucleation density of the film increased. But the greater part of the film was formed with cauliflower-shaped amorphous carbon. These amorphous carbn were crystallized etching amorphous carbon.

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Mild and Efficient Silylcyanation of Aldehydes Catalyzed by Zirconium Complex

  • Kim, Sung-Soo;Lee, Jun-Tae;Song, Dae-Ho;Lee, Ik-Mo;Park, Sun-Young
    • Bulletin of the Korean Chemical Society
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    • v.26 no.2
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    • pp.265-267
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    • 2005
  • An efficient method of addition of trimethylsilyl cyanide to aldehydes by employing a zirconium complex as the catalyst has been described. A variety of aromatic, aliphatic, cyclic and heterocyclic aldehydes has been converted into corresponding trimethylsilyl ethers in excellent yield within short reaction time.

Effects of diamond abrasive and lubricants on mechanical properties and wearing resistance of microblades (첨가된 다이아몬드 abrasive와 윤활제의 함량이 마이크로블레이드의 내구성과 기계적 특성에 미치는 영향)

  • Kim, Song-Hui;Mun, Jong-Cheol;Kim, Sang-U
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2007.11a
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    • pp.134-135
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    • 2007
  • Graphite and MoS2 were added respectively as a lubricant to improve the cutting efficiency of micro blades which contains diamond abrasive. Strength, fracture toughness, and life span of micro-blades were observed to decrease with the increase in diamond abrasive and lubricant content. Wearing mode of micro-blades and the cutting efficiency were also found to be affected by the content of diamond abrasive and the addition of lubricants.

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Effects of Rare Earth Metals Addition and Aging Treatment on the Corrosion Resistance and Mechanical Properties of Super Duplex Stainless Steels

  • 박용수;김순태;이인성;송치복
    • Transactions of Materials Processing
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    • v.8 no.3
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    • pp.309-309
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    • 1999
  • Effects of rare earth metals addition and aging treatment on corrosion resistance and mechanical properties of super duplex stainless steels were investigated using optical/SEM/TEM metallographic examination, an X-ray diffraction test, a potentiodynamic anodic polarization test and a tensile test. The performance of the experimental alloy with 0.32% REM addition was compared with commercial super duplex stainless steel such as SAF 2507 when they were exposed to solution annealing heat treatment and aging treatment. The corrosion resistance in CF environments and mechanical properties of the experimental alloy were found superior to those of the commercial duplex stainless steel. The REM with larger atomic radii than those of Cr, Mo and W may fill vacancies inside the matrix and around the grain boundaries, retarding formation of harmful intermetallic σ and χ phases. In addition, fine REM oxides/oxy-sulfides (1-3㎛) seemed to enhance the retardation effects. With REM additions, strength and ductility increased due to the phase and grain refinement caused by fine REM oxides and oxy-sulfides.

Combustion Characteristics of Methane/Oxygen Gas in Pre-mixed Swirl Flame (메탄/순산소 예혼합 화염의 선회 특성)

  • Choi, Won-Seok;Kim, Han-Seok;Cho, Joo-Hyeong;Kim, Yong-Mo;Ahn, Kook-Young;Woo, Ta-Kwan
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.1979-1983
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    • 2008
  • The effects of carbon dioxide addition to oxygen have been investigated with swirl-stabilized premixed methane flame in a laboratory-scale pre-mixed combustor. The methane fuel and oxydant mixture gas ($CO_2$ and $O_2$) were mixed in a pre-mixer and introduced to the combustor through different degrees of swirl vanes. The flame characteristics were examined for different amount of carbon dioxide addition to the methane fuel and different swirl strengths. The effects of carbon dioxide addition and swirl intensity on the combustion characteristics of pre-mixed methane flames were examined using chemiluminescence techniques to provide information about flow field. The results show that the flame area increases at upstream of reaction zone because of increase in recirculation flow for increase in swirl intensity. The flame area is also increased at the downstream zone by recirculation flow because of increase in swirl intensity which results in higher centrifugal force. The OH and CH radical intensity of reaction zone decrease with carbon dioxide addition because the carbon dioxide plays a role of dilution gas in the reaction zone.

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Quality Characteristics of White Bread Mixed with Blanched Seomcho (Spinacia oleracea L.) Powder (Blanched 섬초(시금치) 분말을 첨가한 식빵의 품질 특성)

  • Kim, Young-Mo
    • The Korean Journal of Food And Nutrition
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    • v.31 no.6
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    • pp.873-882
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    • 2018
  • This research is about the quality characteristics of white bread mixed with varying ratios of Seomcho powder, such as 1%, 3%, 5%, and 7% (Spinacia oleracea L.). The pH level of dough decreased as more Seomcho powder (Spinacia oleracea L.) was added, and 7% addition recorded the lowest pH. The fermentation power of dough expansion decreased as the additional ratio increased in both the first and second proofing, and it was negatively correlated to the fermentation time factor. The moisture content of bread decreased as the addition ratio increased. The bread volume became smaller as the addition ratio increased, but it correlated negatively with its specific volume. The color of the crumb, the lightness and redness decreased in comparison to the control, but the yellowness increased. The total amino acid contents increased as the addition ratio increased, and glutamic acid was positively correlated to the additional ratio. The total free amino acids increased as the additional ratio increased, but cysteine levels were high at 5% and 7% additional ratio. The textural characteristics of the bread, springiness and cohesiveness were lower than the control, but gumminess, brittleness, and hardness were higher than the control. The adhesiveness was realized at 7% additional ratio.

Dietary Intakes, Serum Concentrations, and Urinary Excretions of Fe, Zn, Cu, Mn, Se, Mo, and Cr of Korean Young Adult Women (일부 젊은 성인여자의 Fe, Zn, Cu, Mn, Se, Mo 및 Cr의 식사섭취, 혈청농도 및 소변배설)

  • Kim, Kyune-Hee;Lim, Hyeon-Sook
    • Journal of Nutrition and Health
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    • v.39 no.8
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    • pp.762-772
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    • 2006
  • This study was conducted to investigate dietary intakes, serum concentrations, and urinary excretions of iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), selenium (Se), molybdenum (Mo), and chromium (Cr) of Korean young adult women. A total of 19 apparently healthy young adult women aged in their twenties or thirties participated voluntarily. One-tenth of all foods they consumed for 3 consecutive days were collected, all urine excreted for the same 3 days was gathered, and fasting venous blood was withdrawn for the trace mineral analyses. Of the food, blood, and urine samples, the contents of Zn, Cu, Mn, Se, Mo, and Cr were analyzed by inductively coupled plasma-mass spectroscopy (ICP-MS) and that of Fe by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) after wet digestion. The intake of Fe, $6.94{\pm}2.18mg$, did not meet the estimated average requirement (EAR) for Korean women aged 20-29 years old. On the contrary, the intakes of Zn ($9.35{\pm}4.95mg$), Cu ($1.18{\pm}0.26mg$), and Mn ($3.69{\pm}0.69mg$) were sufficient for each respective EAR. However, some of the subjects did not take the EAR for Zn. The Se intake, $41.93{\pm}9.28{\mu}g$, however, was almost similar to the EAR for Se. Although there are no references for Mo and Cr, the intakes of these minerals ($134.0{\pm}49.1\;and\;136.5{\pm}147.9{\mu}g$, respectively) seemed to be excessively sufficient. Serum Fe concentration, $88.7{\pm}36.8{\mu}g/dL$, seemed to be a little bit lower than its reference median but within its normal range. Approximately one-fourth of the subjects were in anemic determined by Hb and Hct and below the deficiency serum level of Fe, $60{\mu}g/dL$. In addition, serum Se concentration, $3.73{\pm}0.60{\mu}g/dL$, was also below its reference median and normal range. However, serum concentrations of Zn ($99.6{\pm}30.6{\mu}g/dL$) and Mo ($0.25{\pm}0.10{\mu}g/dL$) were fairly good compared to each reference median. The status of Cu could be determined as good although its serum concentration ($91.6{\pm}14.6{\mu}g/dL$) was slightly below its reference median. Since there are no decisive reference values, it was not easy to evaluate serum concentrations of Mn ($0.93{\pm}0.85{\mu}g/dL$) and Cr ($8.60{\pm}7.25{\mu}g/dL$). But Mn and Cr status seemed to be adequate. Urinary Fe excretion, $4.48{\pm}1.98{\mu}g/dL$, was pretty much lower than its reference and that of Se, $2.45{\pm}1.17{\mu}g/dL$, was also lower than its average. On the other hand, those of Zn ($42.95{\pm}20.47{\mu}g/dL$) and Cu ($5.68{\pm}1.50{\mu}g/dL$) were flirty good. In case of Mn, urinary excretion, $0.31{\pm}0.09{\mu}g/dL$, was much greater than its reference. Urinary excretions of Mo ($7.48{\pm}2.95{\mu}g/dL$) and Cr ($1.37{\pm}0.41{\mu}g/dL$) were very higher compared to each reference. The results of this study revealed that Korean young adult women were considerably poor in Fe status, a bit inadequate in Se status, partly inadequate in Zn status, and flirty good in Cu, Mn, Mo and Cr status. However, there was a problem of excessive intakes of Mo and Cr. It, therefore, should be concerned to increase the intakes of Fe, Se and Zn but to decrease Mo and Cr consumption for young adult women.