• 제목/요약/키워드: $Li^+$

검색결과 17,996건 처리시간 0.039초

Anode processes on Pt and ceramic anodes in chloride and oxide-chloride melts

  • Mullabaev, A.R.;Kovrov, V.A.;Kholkina, A.S.;Zaikov, Yu.P.
    • Nuclear Engineering and Technology
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    • 제54권3호
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    • pp.965-974
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    • 2022
  • Platinum anodes are widely used for metal oxides reduction in LiCl-Li2O, however high-cost and low-corrosion resistance hinder their implementation. NiO-Li2O ceramics is an alternative corrosion resistant anode material. Anode processes on platinum and NiO-Li2O ceramics were studied in (80 mol.%) LiCl-(20mol.%)KCl and (80 mol.%)LiCl-(20 mol.%)KCl-Li2O melts by cyclic voltammetry, potentiostatic and galvanostatic electrolysis. Experiments performed in the LiCl-KCl melt without Li2O illustrate that a Pt anode dissolution causes the Pt2+ ions formation at 3.14 V and 550℃ and at 3.04 V and 650℃. A two-stage Pt oxidation was observed in the melts with the Li2O at 2.40 ÷ 2.43 V, which resulted in the Li2PtO3 formation. Oxygen current efficiency of the Pt anode at 2.8 V and 650℃ reached about 96%. The anode process on the NiO-Li2O electrode in the LiCl-KCl melt without Li2O proceeds at the potentials more positive than 3.1 V and results in the electrochemical decomposition of ceramic electrode to NiO and O2. Oxygen current efficiency on NiO-Li2O is close to 100%. The NiO-Li2O ceramic anode demonstrated good electrochemical characteristics during the galvanostatic electrolysis at 0.25 A/cm2 for 35 h and may be successfully used for pyrochemical treating of spent nuclear fuel.

태양열을 증발기 열원으로 사용($20{\sim}40^{\circ}C$범위)하며 LiSCN+LiBr 수용액을 사용하는 흡수식 2중효용 난방시스템의 열역학적 해석 (Thermodynamic Analysis of a Double-Effect Absorption Heating System Using Water-LiBr- LiSCN Solution As $20{\sim}40^{\circ}C$ Range Solar Evaporator Heating)

  • 원승호
    • 한국태양에너지학회 논문집
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    • 제26권4호
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    • pp.73-81
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    • 2006
  • In this paper, with water-LiBr-LiSCN mixture which utilizes solar energy as mid temperature range evaporator heat source, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system. A comparative study of the water-LiBr-LiSCN mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiBr-LiSCN mixture than for the water-LiBr pair, and FR is lower for the former.

$Li_2O-Al_2O_3-Ta_2O_5$ 삼성분계에 있어 $LiTaO_3$ 고용체의 구조 및 특성에 관한 연구 (Structure and Properties of $LiTaO_3$ Type Solid Solutions in $Li_2O-Al_2O_3-Ta_2O_5$ Ternary System)

  • 김정돈;흥국선;주기태
    • 한국세라믹학회지
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    • 제33권4호
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    • pp.405-410
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    • 1996
  • The partial substitution of LiTaO3 with Al2O3 caused the variation of dielectric properties and a lower melting temperature yielding an easier growth of single crystal. The lattice constants and Raman band broadening were measured for the LiTaO3 solid solution in which the cations of Li+ and Ta5+ were partially substituted by Al3+ cation. The LiTaO3 type limit phases were obtained. ; Li1.15Al0.45Ta0.7O3 for cationic excess Li1.15Al0.45Ta0.7O3 for stoichiometry Li0.85Al0.05TaO3 for cationic deficit. The second phase was formed beyond the solubility limit. The limit phase (Li0.85Al0.05TaO3) in the region of cationic deficit showed the lowest Cuire temperature of 61$0^{\circ}C$ and melting point of 152$0^{\circ}C$ compared to the solid solutions in other regions (TMp=1$650^{\circ}C$, Tc=69$0^{\circ}C$ for LiTaO3)

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Electrochemical Properties of Binary Electrolytes for Lithium-sulfur Batteries

  • Kim, Hyung-Sun;Jeong, Chang-Sik
    • Bulletin of the Korean Chemical Society
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    • 제32권10호
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    • pp.3682-3686
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    • 2011
  • The electrochemical properties of lithium-sulfur batteries with binary electrolytes based on DME and DOL, TEGDME and DOL mixed solvent containing $LiClO_4$, LiTFSI, and LiTF salts were investigated. The ionic conductivity of 1M LiTFSI and $LiClO_4$ electrolytes based on TEGDME and DOL increased as the volume ratio of DOL solvent increased, because DOL effectively reduces the viscosity of the above electrolytes medium under the same salts concentration. The first discharge capacity of lithium-sulfur batteries in the DME and DOL-based electrolyte followed this order: LiTFSI (1,000 mAh/g) > LiTF (850 mAh/g) > $LiClO_4$ (750 mAh/g). In case of the electrolyte based on TEGDME and DOL, the first discharge capacity of batteries followed this order: $LiClO_4$ (1,030 mAh/g) > LiTF (770 mAh/g) > LiTFSI (750 mAh/g). The cyclic efficiency of lithium-sulfur batteries at 1M $LiClO_4$ electrolytes is higher than that of batteries at other lithium salts-based electrolytes. Lithium-sulfur battery showed discharge capacity of 550 mAh/g until 20 cycles at all electrolytes based on DME and DOL solvent. By contrast, the discharge capacity of batteries was about 450 mAh/g at 1M LiTFSI and LiTF electrolytes based on TEGDME and DOL solvent after 20 cycles.

LiCl 및 LiCl-${Li_2}O$ 용융염에서 Fe-Ni-Cr 합금의 부식거동 연구 (A Study on the Corrosion Behavior of Fe-Ni-Cr Alloys in Molten Salts of LiCl and LiCl-${Li_2}O$)

  • 조수행;장준선;홍순선;신영준;박현수
    • 한국재료학회지
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    • 제10권7호
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    • pp.471-477
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    • 2000
  • Fe-Ni-Cr 합금의 용융염 부식거동을 $650~850^{\circ}C$ 온도범위에서 조사하였다. 용융염 LiCl에서 Cr을 포함하지 않는 KSA(Kaeri Superalloy)-1 합금은 Fe의 내부산화가 발생하고, Cr을 포함한 KSA-4, Incoloy 800H와 KSA-5는 LiCrO$_2$의 치밀한 보호막이 형성되었다. 혼합용융염 $LiCl-LiO_2$O에서 KSA-1은 Fe의 내부산화, KSA-4는 Cr의 내부산화가 발생하였고, Cr 농도가 높은 Incoloy 800H와 KSA-5는 $LiCrO_2$의 다공성 피 이 형성되었다. 혼합용융염 $LiCl-Li_2$O 에서는 Cr 농도의 증가에 따라 부식속도가 증가하였으며, 부식속도는 시간의존선을 8%Cr 이하의 합금에서는 포물선법칙, 8%Cr 이상의 합금에서는 직선법칙을 나타내었다. 이러한 현상은 Li$_2$O에 의한 보호성 산화물 $Cr_2O_3$의 염기성 용해기구로 설명할 수 있다.

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Classification of Li(黎族) traditional brocade patterns of Chinese textile and its application for modern fashion product design

  • Zhang, Shunai;Wu, Simin
    • 복식문화연구
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    • 제20권5호
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    • pp.775-781
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    • 2012
  • There are various kinds of patterns on Li brocade textile of Hainan province in China. Those patterns are rich and colorful. Li (黎族) traditional brocade is an ancient exquisite craftsmanship and a world cultural heritage. This study analyzed and categorized Li brocade pattern of traditional Chinese textiles. Li (黎族) traditional brocade is an ancient exquisite craftsmanship. Based on the research of classifications of Li brocade patterns, expound the application of women's costume. The patterns of Li brocade textile of Hainan province analyzed through three levels: design transforming, meaning prolongation, and refining spirit. The patterns were explored the feasibility way to inherit the patterns of Li brocade for the modern fashion product design. The results showed that Li brocade textile pattern of Hainan province were images sourced from local environment and geographical terrain. They contained the nation's history memory, religion, hope for life of the Li nationality. Those patterns can be categorized as human figure pattern, animal pattern, geometric pattern, appliance or architecture pattern, and Chinese character pattern.

의사이성분계, Li2Cr2O4-MgCr2O4와 Li2Cr2O4-MgAl2O4에서의 LiCrO2 고용체 형성과 결합구조 (Solid Solution and Defect Structure of LiCrO2 in the Pseudo-binary Systems : Li2Cr2O4-MgAl2O4)

  • 정영서;오근호;김호기
    • 한국세라믹학회지
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    • 제25권1호
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    • pp.35-41
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    • 1988
  • In the system of Li2O-MgO-Al2O3-Cr2O3, the crystalline solid solution of LiCrO2 along the pseudo-binary join between rocksalt structure(LiCrO2) and spinel structure(MgCr2O4 or MgAl2O4) have been investigated by x-ray diffraction techniques. In this study, order-disorder phase transition of LiCrO2 was observed and the unit cell of the disordered LiCrO2 structure has been established. It has been found that LiCrO2 makes a solid solution over a wide range with MgAl2O4, while not with MgCr2O4. This difference was explained as being due to the ability of oxygen lattice distortion which depended on the relative sizes and chemical bonding characteristics of the substituted ions.

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리튬 폴리머 전지 $LiFePO_4$의 전기화학적 특성 (Electrochamical Properties of $LiFePO_4$ Electrodes for Lithium Polymer Battery)

  • 공명철;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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    • pp.5-9
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    • 2005
  • $LiFePO_4$ is a potential candidate for the cathode material of the lithium polymer batteries. $LiFePO_4$ cathode active materials were synthesized by coating on the $LiFePO_4$ was tried using $TiO_2$ and corbon in oreder to increase cyclic performance and electronic conductivity. Highly dispersed on the particles enhances the electronic conductivity and increases the capacity. For lithium polymer battery applications, $LiFePO_4$/SPE/Li and $LiFePO_4$-$TiO_2$/SPE/Li 'cells were characterized electrochemically by cyclic volatammetry and charge/discharge cycling. The $LiFePO_4$-carbon-$TiO_2$ cathode in PVDF-PC-EC-$LiCIO_4$ electrolyte showed high capacity at high current density.

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Li 도핑된 NiO 합성 및 열전식 수소센서에의 적용 (Synthesis of Li-doped NiO and its application of thermoelectric gas sensor)

  • 한치환;한상도;김병권
    • 한국수소및신에너지학회논문집
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    • 제16권2호
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    • pp.136-141
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    • 2005
  • Li-doped NiO was synthesized by molten salt method. $LiNO_3$-LiOH flux was used as a source for Li doping. $NiCl_2$ was added to the molten Li flux and then processed to make the Li-doped NiO material. Li:Ni ratios were maintained from 5:1 to 30:1 during the synthetic procedure and the Li doping amount of synthesized materials were found between 0.086-0.190 as a Li ion to Ni ion ratio. Li doping did not change the basic cubic structural characteristics of NiO as evidenced by XRD studies, however the lattice parameter decreased from 0.41769nm in pure NiO to 0.41271nm as Li doping amount increased. Hydrogen gas sensors were fabricated using these materials as thick films on alumina substrates. The half surface of each sensor was coated with the Pt catalyst. The sensor when exposed to the hydrogen gas blended in air, heated up the catalytic surface leaving rest half surface (without catalyst) cold. The thermoelectric voltage thus built up along the hot and cold surface of the Li-doped NiO made the basis for detecting hydrogen gas. The linearity of the voltage signal vs $H_2$ concentration was checked up to 4% of $H_2$ in air (as higher concentrations above 4.65% are explosive in air) using Li doped NiO of Li ion/Ni ion=0.111 as the sensor material. The response time T90 and the recovery time RT90 were less than 25 sec. There was minimum interference of other gases and hence $H_2$ gas can easily be detected.

LPE법으로 성장시킨 $Zn:LiNbO_3/Mg:LiNbO_3$ 단결정 박막의 구조적 특성 (Structural properties of $Zn:LiNbO_3/Mg:LiNbO_3$ single crystal thin films grown by LPE method)

  • 이호준;신동익;이종호;윤대호
    • 한국결정성장학회지
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    • 제15권3호
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    • pp.120-123
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    • 2005
  • [ $Li_2CO_3-V_2O_5$ ], flux를 사용한 liquid phase epitaxy(LPE) 법을 사용하여 $LiNbO_3$ (001) 기판위에 5 mol% ZnO가 첨가된 $LiNbO_3$, 박막과 2 mol% MgO가 첨가된 $LiNbO_3$, 박막을 성장시켰다. $Zn:LiNbO_3$, 막과 $Mg:LiNbO_3$, 막과의 결정성과 격자 부정합은 x-ray rocking curve(XRC)로 분석되었다. 그리고 다층 박막의 단면에서의 ZnO와 MgO의 분포가 electron probe micro analyzer(EPMA)를 사용하여 관측되었다.