• 제목/요약/키워드: MnS

검색결과 2,056건 처리시간 0.031초

Cupferron과 Tetrabutylammonium ion을 이용한 Mn(II)의 상승용매 추출에 관한 연구 (Synergistic Solvent Extraction of Manganese(II) by using Cupferron and Tetrabutylammonium ion)

  • 인교;소진환;최종문;김영상
    • 분석과학
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    • 제17권1호
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    • pp.1-7
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    • 2004
  • N-nitroso-N-phenylhydroxylamineammonium salt(cupferron)과 tetrabutylammonium ion ($TBA^+$)을 사용하여 수용액 중 미량 Mn(II)을 상승 용매 추출하는 법에 대해서 연구하였다. $TBA^+$가 존재할 때 cupferron으로 수용액 중의 Mn(II)을 추출하면 용액의 pH 4-10 범위에서 95% 이상이 추출되지만 $TBA^+$가 존재하지 않으면 거의 추출되지 않았다. 이런 조건에서 Mn(II)의 추출은 $CH_2Cl_2$$CHCl_3$와 같은 유기용매를 사용 할 때가 다른 비극성 용매를 사용할 때 보다 현저히 잘 추출되었으므로 여기서는 chloroform을 사용하였다. 그리고 수용액의 pH는 5로 조절하였다. 실제시료 중 존재하는 극미량의 Mn(II)을 정량하기 위해서는 chloroform에 추출된 Mn(II)을 다시 0.1 mol/L $HNO_3$용액에 역 추출하여 GF-AAS로 Mn(II)의 흡광도를 측정하였다. 본 방법으로 얻은 Mn(II)의 검출한계는 0.37 ng/mL이었고, 이 방법을 응용하여 실험실 수돗물 중 Mn(II)을 정량한 결과는 0.4-1.01 ng/mL로 얻어졌다. 이 시료에 일정량의 Mn(II)용액을 첨가하여 얻은 회수율은 94-107%이었다. 그리고 Cu(II), Ca(II), Fe(III) 등 공존하는 다른 원소는 10 내지 $20{\mu}g/mL$까지 Mn(II) 정량에 방해를 하지 않았다. 이로서 본 방법이 극미량 Mn(II)의 새로운 분석법으로 사용될 수 있을 것으로 생각된다.

대형주강의 고온파단형태에 미치는 [Mn/S]비의 영향 (The Influence of [Mn/S] Ratios on the Fracture Morphology of a Heavy-section Steel Castings at Elevated Temperature)

  • 김성규;김지태;박봉규;박흥일
    • 한국주조공학회지
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    • 제34권5호
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    • pp.170-178
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    • 2014
  • Using the Gleeble test, the effects of [Mn/S] ratios and the presence of sulfides on the high-temperature fracture morphology of heavy-section steel castings were analysed via the observations of the microstructures. The specimens for which the [Mn/S] ratio was in the range of 60~80 showed a ductile fracture morphology with an area reduction of more than 60%, while some specimens with similar [Mn/S] ratios showed a brittle fracture morphology with an area reduction of 0.0% due to the liquidation of sulfides at the grain boundary. The fracture morphology was classified into three types in the Gleeble high-temperature tensile test specimens. The first type showed dimple formation at the grain boundary, the formation of globular MnS sulfides, and plastic deformation of sulfides at an elevated temperature, indicating a needle-point type of ductile fracture with area reductions of 96.0~97.8%. The second type was a knife-edge type brittle fracture with an area reduction of 0.0% due to the film-type liquidation of sulfides at the grain boundary, band-type liquidation, and the liquidation of a terraced nipple pattern. The third type was the typical ductile fracture with an area reduction of 31.3~81.0%, in accordance with the mixture of dimples with in the grains and terraced nipple pattern at the grain boundary.

High Exchange Coupling Field and Thermal Stability of Antiferromagnetic Alloy NiMn Spin Valve Films

  • Lee, N. I.;J. H. Yi;Lee, G. Y.;Kim, M. Y.;J. R. Rhee;Lee, S. S.;D. G. Hwang;Park, C. M.
    • Journal of Magnetics
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    • 제5권2호
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    • pp.50-54
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    • 2000
  • NiMn-pinned spin valve films consisting of a layered glass/NiFe/Co/Cu/Co/NiFe/NiMn/Ta stack were made by do magnetron sputtering. After deposition, the structure was annealed in a series of cycles each including three hours at $220^\circ C, 2\times10^{-6}$ Torr, in a field of 350 Oe, to create an ordered antiferromagnetic structure in the NiMn layer and produce a strong unidirectional pinning field in the pinned magnetic layer, Optimum spin valve properties were obtained after seven annealing cycles, or 21 hours at $220^\circ C$, and were : MR ratio 1%, exchange coupling field 620 Oe, and coercivity of pinned layer 250 Oe. The exchange coupling field remained constant up to an operating temperature of $175^\circ C$, and the blocking temperature was about $380^\circ C$.

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변태 유기 소성강(TRIP steel)의 미세구조와 원자 단위 분석 (Atomic Scale Investigation of TRIP Steels)

  • 임남석;강주석;김성일;박찬경
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 추계학술대회 논문집
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    • pp.273-276
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    • 2008
  • In this study, microstructure and distribution of alloy elements were investigated in thermo-mechanically processed C-Mn-Si transformation induced plasticity (TRIP) steels. The microstructures of TRIP steels were investigated by using advanced analysis techniques, such as three dimensional atom probe tomography (3D-APT). At first, the microstructure was observed by using TEM. TEM results revealed that microstructure of C-Mn-Si TRIP steel was composed of ferrite, bainte, and retained austenite. 3D-APT was used to characterize atomic-scale partitioning of added elements at the phase interface. In the retained austenite phase, Ti and B were enriched with C. However, there was no fluctuation of Mn and Si concentration across the interface. Through these analysis techniques, the advanced characteristics of constituent microstructure in C-Mn-Si TRIP steels were identified.

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La-doped $BaTiO_3$ 세라믹스에서 PTCR 특성에 미치는 Mn의 영향 (The Role of Mn on the PTCR Characteristics of La-doped $BaTiO_3$ Ceramics)

  • 김성희;이준형;조상희
    • 한국세라믹학회지
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    • 제32권1호
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    • pp.140-144
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    • 1995
  • The role of Mn on the PTCR characteristics of La-doped BaTiO3 ceramics was studied. The calculated Ns value was increased with Mn concentration and consequently pmax and pmin were increased. The behavior of pmin was explained by the Jonker's theory, and Ns value of 6.35×1017m-2 was well agreed with the theoretical estimate of Jonker's. The value state of Mn was measured by ESR, and changed around Tc from +3 in tetragonal phase to +2 in cubic phase. Therefore, the amount of electron trap increased at Tc led to the great improvement of PTC R characteristics.

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Fe-17wt%Mn 합금의 진동감쇠능, 내후성 및 기계적 성질에 미치는 Cu 첨가의 영향 (Effects of Copper Addition on Damping Capacities, Atmospheric Corrosion and Mechanical Properties of Fe-17wt % Mn Alloy)

  • 백승한;김정철;지광구;최종술
    • 열처리공학회지
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    • 제8권2호
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    • pp.113-119
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    • 1995
  • We have reported that an Fe-17wt%Mn alloy exhibits the highest damping capacity in the Fe-Mn binary system. In the present work, the effects of copper content on the damping capacity, atmospheric corrosion and mechanical properties were studied. The damping capacities were measured at room temperature for the air cooled Fe-17wt%Mn alloy having copper content from 0.1wt% to 1.1wt%. The damping capacity of the Fe-17wt %Mn alloy was decreased with increasing copper content. However, the addition of Copper was found to improve mechanical properties and atmospheric corrosion resistance. These mechanical properties were attributed to the formation of stress-induced martensite during tensile test.

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Study on UV Opto-Electric Properties of ZnS:Mn/ZnS Core-Shell QD

  • Lee, Yun-Ji;Cha, Ji-Min;Yoon, Chang-Bun;Lee, Seong-Eui
    • 한국세라믹학회지
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    • 제55권1호
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    • pp.55-60
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    • 2018
  • In this study, quantum dots composed of $Mn^{2+}$ doped ZnS core and ZnS shell were synthesized using MPA precursor at room temperature. The ZnS: Mn/ZnS quantum dots were prepared by varying the content of MPA in the synthesis of ZnS shells. XRD, Photo-Luminescence (PL), XPS and TEM were used to characterize the properties of the ZnS: Mn/ZnS quantum dots. As a result of PL measurement using UV excitation light at 365 nm, the PL intensity was found to greatly increase when MPA was added at 15 ml, compared to the case with no MPA; the PL peaks shifted from 603 nm to 598 nm. A UV sensor was fabricated by using a sputtering process to form a Pt pattern and placing a QD on the Pt pattern. To verify the characteristics of the sensor, we measured the electrical properties via irradiation with UV, Red, Green, and Blue light. As a result, there were no reactions for the R, G, and B light, but an energy of 3.39 eV was produced with UV light irradiation. For the sensor using ZnS: Mn/ZnS quantum dots, the maximum current (A) value decreased from $4.00{\times}10^{-11}$ A to $2.62{\times}10^{-12}$ A with increasing of the MPA content. As the MPA content increases, the PL intensity improves but the electrical current value dropped because of the electron confinement effect of the core-shell.

Orchardgrass 및 White clover의 단파 및 혼파 재배에서 미량요소(Fe, Mn, Cu, Zn, Mo, B)의 조합시비가 목초의 총 함량, 상대 함량, 탈취량 및 상호비율 변화에 미치는 영향 (Effects of Combined Application of Micronutrients on these Total and Relative Contents, Uptake Amounts, and Mutual Ratios in Orchardgrass and White Clover)

  • Jung, Yeun-Kyu
    • 한국초지조사료학회지
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    • 제24권2호
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    • pp.93-104
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    • 2004
  • Orcharduass 및 white clover의 단파 및 혼파재배조건에서 미량요소 Fe, Mn, Cu, Zn, Mo 및 B의 조합시비가 목초의 생육, 개화, 수양, 양분함량 및 식생구성비율 등에 미치는 영향을 구명하였다. 다양요소 양분을 동일량 시비한 조건에서 7 수준의 미량요소 조합시비는 $T_1$; 대조구, $T_2$; Fe, $T_3$: Fe+Mn, $T_4$; Fe+Mn+Cu, $T_5$ ; Fe+Mn+Cu+Zn, $T_6$ : Fe+Mn+Cu+Zn+Mo 및 $T_7$ ; Fe + Mn +Cu+Zn+Mo + B로 하였다. 본 V보에서는 조합시비가 목초 중 미량요소의 충 함량, 상대함량, 탈취량 및 상호비율의 변화 등에 미치는 영향을 검토하였다. 1) Fe과 Mn-상대함량(총 미량요소 함량=100% 대비)은 이들간의 길항적인 흡수생리와 초종간 he-흡수경합의 차이에 크게 영향을 받았다. orcharduass는 단파에 비해서 혼파재배에서 Mn-상대함량이 더 높았고 B와 Fe-상대함량은 더 낮았으나 white clover는 이와 반대의 경향을 보였다. $T_6$ 6/ 처리에서는 일반적으로 Fe-상대함량의 감소를 보였다. 에서 orchardgrass는 B와 Mn-상대함량의 증가와 Cu와 Zn-상대함량의 감소를 보였으나 white clover는 Mo-상대함량의 감소만 보였다. 2) 미량요소의 탈취량은 일반적으로 수양의 증감에 따른 특성과는 차이를 보였다. 각 미량요소의 탈취량과 미량요소 간 상대함량(당량기준)은 초종, 단파/혼파재배, 추비 및 일부 길항작용의 특성에 따라서 차이를 보였다. 총 미량요소의 탈취량은 일반적으로 증가되는 조합시비 처리에 따라서 증가하였다. Mn을 시비한 조합시비에서는 수양의 면화보다 Fe-탈취량이 상대적으로 더 낮았고 Mn-탈취량은 더 높았다. $T_7$ 처리로 Mn과 B-탈취량은 증가하였고 Mo-탈취량은 감소되었다. 3) Fe/Mn, Fe/Cu와 Mn/Cu 비율은 길항적인 Fe과 Mn 간의 흡수경합에 따라서 크게 영향을 받았다. $T_6$ 처리에 의해서 Fe/Mo 비율은 크게 낮아졌고 이 비율은 $T_7$ 처리로 Mo 함량의 감소와 더불어 다소 높아졌다. B/Mo 비율은 orchardgrass보다 특히 white clover에서 높았고 $T_6$ 에서의 생육불량/황화현상이 $T_7$ 처리에서 양호해진 것은 높아진 B/Mo 비율과도 연관된 것으로 보였다.

일부(一部) 대도시(大都市) 지역(地域) 치과기공사(齒科機工士)의 직업(職業) 및 직업장(職業場) 만족도(滿足度)에 관한 조사연구(調査硏究) (A Study of Satisfaction About Dental technician's Post and Laboratory in Great Cities)

  • 이태정;이명곤
    • 대한치과기공학회지
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    • 제7권1호
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    • pp.41-51
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    • 1985
  • This study has been to survey the present situation of satisfaction to the occupation and dental laboratory by means of selscting 200 dental technicians who are woked in Pusan, Deagu, Kwangju, Deajun. Questionaires were distributed to them and the summerized results were as follows; 1. In general, the dental technician's satisfaction of the occpation was revealed as moderate(Mn, 2.83), the dental technician's satisfaction of the laboratory was revealas moderate(Mn, 2.80). The highest degree item out of the satisfaction of occpation was the outlook(Mn, 3.23), and the lowest degree item was the advancement and the rise to a high position(Mn, 2.22). The highest degree item out of the satisfaction of laboratory was dental material(Mn, 3.07), and the lowest degree item was the equipment of dust collection(Mn, 2.49) 2. By age, the highest degree item out of the satisfaction of occpation was 30 to 43 group(Mn, 3.28), 50 and over group was the lowest degree item(Mn, 2.89). The highest degree item out of the satisfaction of laboratory was 40 to 50 group(Mn, 3.10), the lowest degree item was 35 to 39 group(Mn, 2.88). 3. By school career, the satisfaction of occpation and dental laboratory were higher in the graduated college group than the graduated highschool group. 4. By personal health state, the highest degree item of the satisfaction of occpation was the health group(Mn, 3.25). The highest degree item of the satisfaction of laboratory was the unhealthy group(Mn, 3.07). 5. By religion, the satisfaction if iccupation of laboratory ws higher in the religious group than the non-religious group. 6. By job career, the highest degree item of occupation satisfaction was 15 to 20 years group(Mn, 3.27), the lowest degree item was 20 and over group(Mn, 3.02). The highest degree item out of the satisfaction of laboratory was 15 to 20 years group(Mn, 3.05), The lowest degree item was 7 to 10 years group (Mn, 2.90). 7. By job position, the highest degree item out of satisfaction of occupation was the chief of laboratory group(Mn, 3.33), the head of laboratory group was the lowest degree item(Mn, 3.07). The hightest degree item out of the satisfaction of laboratory was the head of laboratory group(Mn, 3.10), the lowest degree item was the chief of laboratory group(Mn, 2.88). 8. By the place of employment, the degree of occpational satisfaction by items was found that the highest degree in the group engagel in general hospital(Mm, 3.43), the group engaged in dental clinic and hospital(Mn. 3.24), and the dental laboratory group(Mn. 3.14) in order. The difference among the group was significant emough(P<0.05). The highest degree item out of the satisfaction of laboratory was dental laboratory group(Mn. 2.70). The difference among the group was significant emough(P<0.01). 9. By monthly salary, the highest degree item out of the satisfaction of occupation was ₩500,000 to 600,000 group(Mn. 3.32), the lowest degree item was ₩600,000 and over group(Mn, 3.07). The highest degree item out of the laboratory satisfaction was ₩100,000 to 200,000 group(Mn, 3.03), the lowest degree group was ₩300,000 to 400,000 group(Mn, 2.95). 10. As compared with the degree of satisfaction according to job satisfaction, the highest degree item out of the occupational satisfaction was much satisfied group(Mn, 3.65), the lowest degree item was non-satisfied group(Mn, 2.68). The difference among the group was significant enough(P<0.05). The highest degree item out of the satisfaction of laboratory was non-satisfied group(Mn, 30.9), the lowest degree item was satisfied group(Mn, 2.84). The difference among the group was significant enough(P<0.01).

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ZnS:Mn/Cu,Cl계 나노 형광체 EL의 발광 특성 연구

  • 금정훈;이성의
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.291-291
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    • 2009
  • ZnS:Mn/Cu,Cl 계 나노 형광체의 특성을 살펴보았다. 실험에서는 ZnS:Mn 과 ZnS:Cu,Cl 형광체 파우더를 이용하여 밀링을 통하여 분쇄하여 EL 소자를 제작하였다. 형광체 파우더를 볼밀에 $\Phi5mm$의 지르코나이 볼과 에탄올과 함께 넣고 2, 4, 6, 8, 10일간 밀링을 하였다. 밀링한 형광체 파우더를 SEM을 통하여 파우더의 사이즈를 관찰하였다. 또 이 파우더를 이용하여 EL 소자를 제작하였다. 소자의 구조는 기판은 알루미나 기판을, 하부 전극은 Au, 유전체는 $BaTiO_3$ 유전체 페이스트를 사용하였으며, 형광체 적층 후 ITO 전극을 스퍼터를 이용하여 증착하여 제작하였다. 제작한 소자를 이용하여 소자의 휘도 등 발광 특성을 살펴보았다.

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