• 제목/요약/키워드: MH

검색결과 580건 처리시간 0.021초

니켈-수소 2차전지용 철-티타늄계 전극용 합금제조 공정에 관한 연구 (A study on the fabrication process development of FeTi type alloy for Ni/MH battery)

  • 이문구;김을수;정순돌;김기원;안효준
    • 한국수소및신에너지학회논문집
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    • 제10권1호
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    • pp.1-7
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    • 1999
  • In order to study on the effect of fabrication methods on the changes of hydrogenation properties of FeTi alloy, FeTi samples were prepared using three different methods, i.e., arc melting, mechanical alloying and combination of the two methods. The FeTi prepared by mechanical alloying represented amorphous structure. The hydrogen storage capacity of arc melted FeTi alloy is larger than any other samples. However, FeTi electrode fabricated by mechanical alloying after arc melting showed largest discharge capacity among them.

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니켈박판과 다공질니켈박판의 샌드위치 판넬 용접 특성 (Characteristics on Sandwich Panel Welding of a Ni Thin Plate and Porous Ni Thin Plate)

  • 황찬연;양윤석;유영태
    • 한국생산제조학회지
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    • 제21권4호
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    • pp.547-555
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    • 2012
  • This paper focuses on the research of the anode and cathode in the Ni-MH secondary battery. In this paper, the proposed method employs a continuous wave Nd : YAG laser based on the pure Ni instead of the low carbon steel to improve the conductivity although the conventional secondary battery is based on the resistance spot welded with low carbon steel SS41. It welds a sandwich panel using the pure Ni and the porous thin plate, and the tested optimal conditions for the laser power and irradiation speed were 300 and 350 Watt, and 1.0~1.6m/min, respectively. Finally, we observed a ratio, heat input and cross-section and measured the conductivity of the welding section to test the weldability.

황색종 담배의 재배방법이 엽중 화학성분에 미치는 영향 (Influences of Cultural Practices on Chemical Composition in Flue - cured Tobacco Leaves.)

  • 반유선;이중호
    • 한국연초학회지
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    • 제13권1호
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    • pp.27-35
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    • 1991
  • These studies were conducted to investigate the changes of starch, sugar and nicotine content in relation to maturity and cultural conditions and correlation between growth characteristics and chemical components in order to improve the leaf quality. The results were summarized as follows; 1. Nicotine content, total nitrogen content and the ratio of total nitrogen to nicotine of the green leaf were increased with heavier fertilizer, wider planting space and lower topping, whereas starch, total sugar and the ratio of sugar to nicotine were decreased. 2. Starch content, sugar content and the ratio of total sugar to nicotine(T-S/Nic) in the cured leaf were decreased with milder planting space, less application of MH and delaying harvesting date. 3. It was estimated that 58.1% of starch of the harvested leaf was converted into sugar of the cured leaf, and also they were significantly correlated each other.

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레이저 메탈 디포지션 변수에 의한 표면경도 특성 분석 (Surface Hardness as a Function of Laser Metal Deposition Parameters)

  • 김원혁;정병훈;박인덕;오명환;최성원;강대민
    • 소성∙가공
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    • 제24권4호
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    • pp.272-279
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    • 2015
  • The characteristics of the laser metal deposition parameters were studied to enhance the deposition efficiency using a diode pumped disk laser. STD61 hot tool steel plate and Fe based AISI M2 alloy were used as a substrate and powder for the laser metal deposition, respectively. Among the laser metal deposition parameters the laser power, track pitch and powder feed rate were used to estimate the deposition efficiency. From the experimental results, the deposition efficiency was shown to be excellent when 1.8kW laser power 500um track pitch and 10g/min of the powder feed rate were used. For this optimal condition the average hardness of the deposition track was approximately 830HV, and this value is 30~50% better than the hardness of the commercially produced tool steel after heat treatment.

다중프로세서 시스템에 적합한 우선순위 할당 결정기법에 관한 연구 (Allocation Priority Scheme for Multiprocessor Systems)

  • 박영선;김화수
    • 한국국방경영분석학회지
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    • 제17권2호
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    • pp.113-122
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    • 1991
  • This paper presents the Allocation Priority Scheme (APS) for multiprocessor system. The objective of APS is to reduce the time-complexity on a Physical Mapping Scheme(PMS). The PMS is to allocate the nodes of the Data Dependency Graph (DDG) to the multprocessors efficiently and effectively. The APS provides the priority to each node (vertex) in the DDG. In other words, the goal of the APS is to find a request resource mapping such that the total cost (time-complexity) is minimized. The special case in which all requests have equal priorities and all resoruces have equal precedences, and the comparisons between our APS and other schems are discussed in the paper. The APS provides the heuristic rules which are based on maximum height (MH), number of children nodes ($N_c$), number of father nodes ($N_f$), and computation time ($T_c$). The estimation moth of the computaion time is in the paper.

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근거리 무선전력 전송용 공진형 class Φ2 인버터 고효율 최적설계 (The High Efficiency Optimal Design of Resonant class Φ2 Inverter for short range wireless power transmission)

  • 양해열;박재현;김창선
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2011년도 전력전자학술대회
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    • pp.64-65
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    • 2011
  • The ac power conversion inverter provides the ac power to ECR device for wireless power transfer. In this paper, the operating efficiency of the class-${\Phi}_2$ resonant inverter has been studied through by experiment for optimal design. Its switching frequency is 1MH and the input voltage is 96V which is the output voltage of LLC resonant converter. And its output voltage is 230Vp-p. The efficiency is measured up to 84%.

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Anti-inflammatory effects of Fangchinoline and Tetrandrine

  • Kim, Hack-Seang;Park, Hong-Serck;Kim, Young-Soo;Oh, Ki-Wan
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1997년도 춘계학술대회
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    • pp.89-89
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    • 1997
  • Fangchinoline and Tetrandrine are the major alkaloids of bis-benzylisoquinoline structure isolated from Stephania tetrandra which has been used as anti-inflammatory drug. The purpose of this study was to investigate the inhibitory effects of Fangchinoline and Tetrandrine on cyclooxygenase, interleukin-5(IL-5) and interleukin-6 (IL-6) as anti-inflammatory mechanisms. Tetrandrine at 100 ${\mu}$M did not show any inhibitory effect but Fangchinoline showed 31% of inhibition on cyclooxygenase. In addition, in mIL-5-dependent Y16 proliferation assay, Tetrandrine at 30 ${\mu}$M exhibited more than 50% of inhibition but Fangchinoline did not any effect. However in hIL-6-dependent MH60 proliferation assay, more than 50% of inhibition was observed by both of Fangchincline and Tetrandrine at 30 ${\mu}$M. Fangchinoline and Tetrandrine also showed anti-inflammatory effects by croton oil induced mouse ear edema test.

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Polyaniline의 합성과 이를 이용한 고분자 발열체에 관한 연구 (A Study of Polymer Heater Using Conducting Polymer)

  • 임동준;임석범;양준모;김은옥;김영호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.802-805
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    • 2001
  • Conductive polymer is insulator or semiconductor in initial state. Polyaniline(PANI) is a $\pi$-conjugated polymer that shows electric property changes, when it is contact with oxidant/reductor chemicals. Synthesis of polyaniline is used vacuum evaporation method, using by (NH$_4$)$_2$O$_{8}$과 NMP, NH$_2$NH$_2$, HCl, MH$_4$OH, etc. Doped PANI is used such a resistor, addition to graphite is increased conductivity. Applying contact voltage, samples show constant current and contact temperature.e.

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기계적 합금화법에 의한 Ti-Fe-X계 수소 저장합금의 제조에 관한 연구 (Development of Ti-Fe-X metal hydride electrode by mechanical alloying)

  • 하창진;이경섭
    • 한국재료학회지
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    • 제5권1호
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    • pp.112-122
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    • 1995
  • Metal hydride alloys of TiFe based system have been produced by mechanical alloying(MA) method and their electrochemical characteristics have been evaluated for application for Ni/MH battery electrode. These alloys became amorphous after 36hrs ball milling and easily activated electrochemically. All MA amorphous alloys reached at the first charge/discharge cycle the maximum capacity which was 2-3 times higher than the crystalline state. But their cyclic lives were much inferior to the crystalline state. Alloying elements such as Ni, Co, Cr, Mo substituting Fe greatly improved the capacity and 180 mAh/g capacity was obtained in an alloy of TiFe_{0.6}Ni_{0.1}Co_{0.1}Cr_{0.1}Mo_{0.1}$.

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국산 Propolis의 항균 ${\cdot}$ 살균효과에 대한 연구(II)

  • 박돈희;양송원;강춘형;백운화;김희성
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.777-780
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    • 2000
  • Propolis는 꿀벌이 다양한 식물로부터 모아온 수지상의 물질이며 꿀벌의 분비물과 수목의 삼출액 등의 다양한 형태를 함유하고 있다. Propolis는 고대로부터 항생작용과 상처치유에 효과적인 혼합물로 알려져 있다. 또한 에탄올 추출 Propolis는 항박테리아, 항미생물, 항곰팡이, 마취성, 항염증, 통증저하, 면역상승과 세포증식억제작용 특성과 같은 약물학적 활성을 나타낸다고 알려져 있다. 이 연구에서는 국내산 Crude Propolis로부터 얻어진 EEP의 첨가가 미생물의 성장에 미치는 영향을 조사하였다. Paper Disc Diffusion Method와 균주의 성장에 따른 저해 정도를 확인하기 위한 20mg EEP/100mL MH배지에서도 균주의 성장을 저해함을 확인할 수 있었다. 70% EEP와 95% EEP에서 모두 저해를 확인할 수 있었고95% EEP에서 저해활성이 더 좋았다.

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