• 제목/요약/키워드: Fe-Cr

검색결과 1,717건 처리시간 0.027초

소금의 종류별 미네랄 함량과 외형구조 비교연구 (Comparison of Mineral Content and External Structure of Various Salts)

  • 박건영;하정옥
    • 한국식품영양과학회지
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    • 제27권3호
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    • pp.413-418
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    • 1998
  • There are several types of salts that classifed into raw salts(Chunil salt, Saeng salt), purified salts (NaCl reagent grade, Hanju salt) and processed salts(Gueun salt, Saeng kum, Bamboo salt) in Korea. Their major element is NaCl but raw salt from sea water contains other minerals such as K, Mg and S. Mineral contents of the various kinds of salt analyzed with ICP-AES and AAS were different, especially on the contents of K, Mg and Ca. Chunil salt was abundant in Ca(1,037ppm), K(3,707ppm), Mg(10,266ppm) and S(7,459ppm), and salt water from the Chunil salt contained small amounts of Pb, Al, Cr and Hg. Processed salts contained high levels of Ca, K, Mg and Fe. Especially, high levels of K, P, Fe and Ge were detected in bamboo salt. Purified salts showed regular crystal form and raw salts exhibited irregular crystal form under the SEM. The processed salts were not crystal form, but fused and irregular round form.

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Effect of Alloying Elements on the Thermal Creep of Zirconium Alloys

  • Cheol Nam;Kim, Kyeong-Ho;Lee, Myung-Ho;Jeong, Yong-Hwan
    • Nuclear Engineering and Technology
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    • 제32권4호
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    • pp.372-378
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    • 2000
  • The effect of alloying elements on the creep resistance of Zr alloys was investigated using thermal creep tests that were performed as a part of advanced fuel cladding development. The creep tests were conducted at 40$0^{\circ}C$ and 150 MPa for 240 hr. A statistical model was derived from the relationship between the steady-state creep rate and the content of individual alloying elements. The creep strengthening effect decreased in the following sequence : Nb, Sn, Mn, Cr, Mo, Fe and Cu. The high creep resistance of Sn and the opposite effect of Fe on zirconium alloys seem to be associated with their lowering and enhancing, respectively, the self-diffusivity of the zirconium matrix.

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Synthesis and Characterization of Colorimetric Chemosensors Using New Direct Dyes

  • Heo, Eun-Yeong;Kim, Sung-Hoon;Bae, Jin-Seok
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2009년도 학술발표대회
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    • pp.162-163
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    • 2009
  • Colorimetric chemosensors are now considered as one of the most effective analytical method used in the environmental monitoring. In this study, 10 new direct dyes were synthesized to be used as colorimetric chemosensor. When metal ions such as $Al^{3+},\;Ca^{2+},\;Cd^{2+},\;Cr^{3+},\;Cu^{2+},\;Fe^{2+},\;Fe^{3+},\;Hg{^2+},\;Li^+,\;Mg^{2+},\;Na^+,\;Ni^{2+},\;Pb^{2+}\;and\;Zn^{2+}$ were added to the solutions of new dyes, the colors of the solutions were changed and can be easily detected by eyes without any expensive equipments. Some metal ions were coordinated to the new direct dyes forming complex. The experimental data and conclusions were rationalized by UV-VIS spectroscopy.

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용융탄산염형 연료전지의 분리판 부식특성 (Corrosion characteristics of separator for MCFC)

  • 김귀열;엄승욱;문성인;문길호;최영태
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 C
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    • pp.1407-1408
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    • 1996
  • The development of MCFC is going to the second stage of development and recent studies have been focusing on long-term durability of cell component. Systematic investigation on corrosion behavior of Fe-based alloys has been done in (62+38) mol % (Li+K) $CO_3$ melt at 923K by using steady-state polarization and electrochemical impedance spectroscopy method. It was found that the corrosion current t of these Fe-based alloys decreased with increasing Cr, Al content.

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스테인레스 전기로 최적 원료장입 모델

  • 홍유신;박기진;오성수
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1990년도 춘계공동학술대회논문집; 한국과학기술원; 28 Apr. 1990
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    • pp.100-110
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    • 1990
  • An optimal raw mix model in stainless steel making is developed. The key raw materials in stainless steel making are stainless steel scrap, steel scrap, and alloy materials like Fe-Ni, Fe-Cr. Among those raw materials, the alloy metals are very expensive as well as rapidly price-changing items. Consequently, it is very important to develop an minimal cost raw mix scheme while the produced stainless steel satisfies the required specification in it's composition. The linear programming model is employed to determine the minimal cost raw mix scheme. Compared with the method being used, the developed linear programming model gives much faster and better solution (lower cost raw mix plan). Together with the linear programming model, the database is also developed, which includes the following: 1) data for raw materials, such as compositions, costs, densities, available inventory levels, and so on, 2) the required specifications process. The developed optimal raw mix model will be implemented in VAX computer.

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괴화의 염색성에 관한 연구 (The Study on the Mordanting and Dyeing Properties of Sophora Japonica L.)

  • 주영주;소황옥
    • 복식
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    • 제52권3호
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    • pp.19-27
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    • 2002
  • This paper surveys the mordanting and dyeing properties of Sophora japonica L. Appropriate extraction, dyeing and mordanting condition of Sophora japonica L. were determined, and the effect of mordanting method on dye uptake and color fastness of dyed fabric was investigated. The maximum absorbance of Sophora japonica L. solution was 367.6mn, rutin solution was 365.6mn. The color of Sophora japonica L. solution was affected at pH 2 and pH 8~9. The optimum temperature to extract Sophora japonica L. was during 1 hour in 8$0^{\circ}C$. The effective dyeing temperature and time of silk were 10$0^{\circ}C$, 60min. K/S value of dyeing fabrics was increased by pre-mordanting treatment, especially Fe, Sn, Cr. In the case of Sophora japonica L. light fastness was increased by Fe mordanting. Perspiration fastness was better in acidic solution than that in alkaline solution. Fastness to rubbing and dry-cleaning were good in general.

개나리 꽃잎을 이용한 염색성에 관한 연구 (The Study of the Dyeability of Forsythia Koreana NAKAI)

  • 배상경
    • 한국염색가공학회지
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    • 제15권5호
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    • pp.310-315
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    • 2003
  • The dyeing of cotton fabric with Forsythia koreana NAKAI was investigated. The colorant was extracted with methanol under various concentrations of dyestuffs at $40^\circ{C}$ and $76^\circ{C}$. UV-VIS spectrum was obtained to find the maximum wavelength of colorant. Cotton fabrics were dyed at different temperatures, mordants, in pre and post mordanting methods. The maximum wavelength of spectrum were 390nm, 410nm, 440nm. The highest K/S value was showed at 100% dye concentration, extracted at $76^\circ{C}$ and dyed at $80^\circ{C}$. The mordant effect was not good in the K/S values. The light fastness was increased at Fe-pre mordant and Cr, Fe-post mordant.

오존을 이용한 지하수의 철.망간 및 유기물 제거특성 (Removal Characteristics of Iron, Manganese and Organics in Ground Water Using Ozonation)

  • 선창욱;우달식;남상호
    • 환경위생공학
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    • 제12권2호
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    • pp.43-49
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    • 1997
  • Iron and manganese problems in ground water affect far more water systems than almost any other water quality concern. The purpose of this study is to find the optimum condition of ozonation for the removal of dissolved iron, manganese and other organics in the polluted ground water. We proposed 4mg/l, 8mg/l as optimum ozone dose for the removal of $Fe^{2+},{\;}Mn^{2+}$, respectively. The removal efficiencies of $COD_{Mn}$ and $COD_{Cr}$ in ozone dose of 2mg/l - 6mg/l were about 40-50%. The removal efficiency of $NH_{3}-N$ was about 30-40% at pH8.5. In conclusion, it needs further systematic study and research concerned to treatability of $Fe^{2+},{\;}Mn^{2+}$ and biodegradability of organic compounds using Ozonation followed by biological filtration process in ground water treatment train.

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블루사파이어와 루비의 고온산소 화염처리에 의한 색향상 (Color Enhancement by Oxygen Torch in Blue Sapphires)

  • 송오성;김상엽
    • 한국표면공학회지
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    • 제38권2호
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    • pp.83-87
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    • 2005
  • We enhanced the color of blue sapphires and rubies successfully by using a oxygen-propane torch flame annealing, which had not been employed so far. We confirmed that about 1 mm-thick de-coloring of the corundum samples were available with 60 minutes flame annealing through eye evaluation, color coordination characterization, and methylene iodide immersion observation. We also suggest that the color centers such as $[Fe_{Al}^{\cdot}]$ may transform into transparent $[Fe_{Al}^{x}],\;[Cr_{A1}^{x}]$ sites with $[V_o^']$ generation at the elevated temperature in oxygen-rich atmosphere by diffusion mechanism. Our results implied that the longer diffusion time and the higher oxygen partial pressure might lead to the better de-coloring enhancement in corundum gem stones.

삼백초의 염색성 및 항균성(I) (The Dyeability and Antimicrobial Activity of Saururus Chinensis(I))

  • 김병희;송화순
    • 대한가정학회지
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    • 제38권3호
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    • pp.1-9
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    • 2000
  • Saururus-chinensis was used for the natural due stuff extraction and concentration to produce the condensed dye liquid. Using this liquid, the silk and the cotton fabrics were dyed. And then the K/S value, color difference were measured in order to determine the dye ability and the antimicrobial activity. The K/S values of silk were much higher than those of cotton. In terms of the silk fabric, the Al, Cr-premordanting and Fe, Cu-simmordanting method was most efficient of the mordanting method. The various suface colors on the dyed fabric were resulted according to used mordants and mordanting methods. The dye fastness was significantly improved when mordants were added. Among them, Al-mordant improved more than 1 level. The Cu, Fe-mordants showed the greatest antimicrobial activity on both of mordant treat silk and cotton.

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