• 제목/요약/키워드: 3C 279

검색결과 361건 처리시간 0.027초

LiNiO$_2$/Li cell의 전기화학적 특성 (Electrochemical Properties of LiNiO$_2$/Li cell)

  • 전대규;김철중;성창호;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.279-282
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    • 1997
  • The propose of this study is research and improvement of LiNiO$_2$as cathode material for Lithium secondary batteries. LiNiO$_2$is prepared by heating LiOH . $H_2O$ and Ni(OH)$_2$(mole ratio 1 : 1) on various heat condition. In the result of XRD mesurement, all LiNiO$_2$prepared at this study showed hexagonal structure. In Cyclic Voltammetry, LiNiO$_2$is not conspicous about oxidation peak but oxidation curve change steeply over 3.8V and reduction peak discover at 3.6V. In discharge capacities, specific capacity is higher $O_2$than air when preliminary heated and 75$0^{\circ}C$ than $700^{\circ}C$, 80$0^{\circ}C$ when heated. Therefore, when preliminary heat at $650^{\circ}C$ $O_2$and heat at 75$0^{\circ}C$ carried out, discharge property is the best.

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Synthetic $\beta$-Lactam Antibiotics V. Antibacterial Activity of Some 7$\beta$[2-(2-Aminothiazol-4-yl)-2-(methoxyimino)acetamido]-3-(quinolinium)thiomethylcephalosporins

  • Lim, Dong-Yeol;Park, Sang-Woo;Kim, You-Seung
    • Archives of Pharmacal Research
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    • 제14권3호
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    • pp.279-281
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    • 1991
  • In the field of cephalosporins, introduction of quaternary heterocyclic methyl goups at the C-3 position has led to a new class of cephalosporins such as cefepime and cefpirome, the so-called 4th generation cephalosporins which are characterized by their potent activity. Since than many efforts were attempted to synthesize more effective analogs.

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미녹시딜의 신나밀 유도체에 관한 물성 및 활성연구 (Properties and Activity of the Cinnamyl Chloride with Minoxidil)

  • 신준수;신영아;박정일;문동철;김박광
    • Biomolecules & Therapeutics
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    • 제4권3호
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    • pp.275-279
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    • 1996
  • We have synthesized the cinnamyl derivative of minoxidil, N-2-cinnamylamino-4-amino-6-piperidinopyrimidine 3-oxide(MINAMYL). Physicochemical properties and structural analysis on this compound were examined. And also, we have screened its antialopecic effect.

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Structural and Electrical Properties of Pb(Zr0.4Ti0.6O3/PbZr0.6Ti0.4)O3 Heterolayered Thick Films

  • Park, Sang-Man;Lee, Sung-Gap;Yun, Sang-Eun;Noh, Hyun-Ji;Lee, Young-Hie;Bae, Seon-Gi
    • Transactions on Electrical and Electronic Materials
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    • 제7권6호
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    • pp.279-282
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    • 2006
  • [ $Pb(Zr_{0.4}Ti_{0.6}O_{3}\;and\;Pb(Zr_{0.6}Ti_{0.4})O_{3}$ ] paste were made and alternately screen-printed on the $Al_{2}O_{3}$ substrates. We have introduced a press-treatment to obtain a good densification of screen printed films. The porosity of the thick films was decreased with increasing the applied pressure and the thick films pressed at 60 MPa showed the dense microstructure and thickness of about $76\;{\mu}m$. The remanent polarization and coercive field increased with increasing applied pressure and the values for the PZT thick films pressed at 60 MPa were $17.04{\mu}C/cm^{2}$ and 78.09 kV/cm, respectively.

부유대용융법에 의한 YMnO$_3$단결정 성장 (The growth YMnO$_3$ single crystals using a floating zone method)

  • 권달회;강승구;김응수;김유택;심광보
    • 한국결정성장학회지
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    • 제10권4호
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    • pp.279-285
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    • 2000
  • 부유대용융법에 의해 비휘발성 기억소자용 강유전성물질인 $YMnO_3$단결정을 육성하였다. 결정성장전 YMnO$_3$분말의 최적합성조건은 $1200^{\circ}C$에서 10시간, 최적원료봉 소결조건으로 $1500^{\circ}C$에서 10시간이었다. 초기 Seed가 없는 상태에서의 실험에서 성장된 단결정의 우선성장방위는 X-ray Laue분석을 통하여 [1010] 임을 알수 있었고 이 결정을 seed로 사용하여 c-축에 수직한 방향으로 $YMnO_3$단결정을 성장하였다 성장된 단결정은 직경 5mm, 길이 50 mm로 양질의 흑청색 결정이었다.

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MOGABA: Monitoring of Gamma-ray Bright AGN with KVN 21-m radio telescopes at 22 and 43GHz

  • 이상성;양지혜;변도영;손봉원
    • 천문학회보
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    • 제36권2호
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    • pp.59.2-59.2
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    • 2011
  • We introduce an ongoing project for monitoring total flux density at 22 and 43GHz, linearly polarized flux, and polarization angle at 22GHz of Gamma-ray bright AGN (Active Galactic Nuclei) with KVN (Korean VLBI Network) 21-m radio telescopes. The project started in May, 2011 with an effective monitoring cycle of 4 days, observing four main objects (3C 454.3, BL Lac, 3C 273, and 3C 279). More objects were included in the source list when they had flared in Gamma-ray. In this paper, we report the current status of the project and preliminary results for the monitoring observations.

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Serum albumin levels and their correlates among individuals with motor disorders at five institutions in Japan

  • Ohwada, Hiroko;Nakayama, Takeo;Kanaya, Yuki;Tanaka, Yuki
    • Nutrition Research and Practice
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    • 제11권1호
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    • pp.57-63
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    • 2017
  • BACKGROUND/OBJECTIVES: The level of serum albumin is an index of nourishment care and management. However, the distribution and correlates of serum albumin levels among individuals with motor disorders have not been reported until now. Therefore, we examined the distribution and correlates of serum albumin levels among individuals with motor disorders. SUBJECTS/METHODS: A cross-sectional study on 249 individuals with motor disabilities (144 men, mean age: 51.4 years; 105 women, mean age: 51.4 years) was conducted at five institutions in Ibaraki Prefecture, Japan in 2008. The results were compared with data from the National Health and Nutrition Survey. RESULTS: The mean serum albumin levels were $4.0{\pm}0.4g/dL$ for men and $3.8{\pm}0.5g/dL$ for women. Overall, 17 (11.8%) men and 25 (23.8%) women had hypoalbuminemia (serum albumin level ${\leq}3.5g/dL$); these proportions were greater than those among healthy Japanese adults (${\leq}1%$). Low serum albumin level was related with female sex, older age, low calf circumference, low relative daily energy intake, low hemoglobin (Hb), low blood platelet count, low high-density lipoprotein cholesterol (HDL-C), low $HbA_{1c}$, and high C-reactive protein (CRP) levels. The strongest correlates, based on standardized betas, were Hb (0.321), CRP (-0.279), and HDL-C (0.279) levels. CONCLUSIONS: These results indicate that the prevalence of hypoalbuminemia is higher in individuals with motor disabilities than in healthy individuals and that inflammation is a strong negative correlate of serum albumin levels. Therefore, inflammation should be examined for the assessment of hypoalbuminemia among institutionalized individuals with motor disabilities.

오미자 첨가 도라지 정과의 제조와 저장 중 품질 변화 (Development and Quality Characteristics of Bellflower Root Jeonggwa Added Omija (Schizandra chinensis Baillon) during Storage)

  • 권후자;박찬성
    • 한국식품저장유통학회지
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    • 제18권3호
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    • pp.279-287
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    • 2011
  • The purpose of this research is to develop bellflower (Platycodon grandiforum) root Jeonggwa as a health food. The Omija (Schizandra chinensis Baillon) water extract with 0-8% (w/w) Jeonggwa added was stored at $25^{\circ}C$ for 12 weeks. The quality characteristics of Jeonggwa during storage were investigated. The Jeonggwa showed a lower pH and a higher acdity as the amount of Omija water extract that was added increased. The moisture content of Jeonggwa were rose from 15-18% to 16-22% within 2 weeks of storage, and remained at that level up to the end of storage. The total viable cells of bellflower root Jeonggwa were 2.1~2.3 log CFU/g and increased in number during storage but never exceeded 4 log CFU/g. The shelf life of the Jeonggwa was extended when the Omija extract was added. The lightness (L), redness (a) and yellowness (b) of the Jeonggwa during its storage at $25^{\circ}C$ were highest in control samples, and the values decreased with the increase in the Omija extract concentration (p<0.001). The mechanical evaluation of the Jeonggwa showed that various tested parameters fell during the storage at $25^{\circ}C$. The hardness and strength of the Jeonggwa significantly decreased as the Omija extract concentration rose (p<0.05). In the ensory evaluation tests, the acceptability of the Jeonggwa was optimal when 4~6% of Omija extract was added to it.

Precipitation of Calcium Phosphate at pH 5.0 for the β Tri-calcium Phosphate Cement

  • Chang, Myung Chul
    • 한국세라믹학회지
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    • 제50권4호
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    • pp.275-279
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    • 2013
  • The purpose of this study was to prepare calcium phosphate cement [CPC] for use in artificial bone. Nano-crystalline calcium phosphate [CaP] was precipitated at $37^{\circ}C$ using highly active $Ca(OH)_2$ in DI water and an aqueous solution of $H_3PO_4$. From the XRD measurements, the nano-CaP powder was close to apatitic TCP phase and the powders fired at $800^{\circ}C$ showed a critical ${\beta}$-TCP phase. A mixture of one mole $CaCO_3$ and two moles di-calcium phosphate was calcined at $1100^{\circ}C$ to make a reference ${\beta}$-TCP material. The nano-CaP powders were added to the normal ${\beta}$-TCP matrix and fired at $900^{\circ}C$ to make a ${\beta}$-TCP block. The sintered block showed improved mechanical strength, which was caused by the solid state interaction between nano-CaP and normal ${\beta}$-TCP.

Radio Variability and Random Walk Noise Properties of Four blazars

  • Park, Jong-Ho;Trippe, Sascha
    • 천문학회보
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    • 제39권1호
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    • pp.45.1-45.1
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    • 2014
  • We present the results of a time series analysis of the long-term radio lightcurves of four blazars: 3C 279, 3C 345, 3C 446, and BL Lacertae. We exploit the data base of the University of Michigan Radio Astronomy Observatory (UMRAO) monitoring program which provides densely sampled lightcurves spanning 32 years in time in three frequency bands located at 4.8, 8, and 14.5,GHz. Our sources show mostly flat or inverted (spectral indices -0.5 < alpha < 0) spectra, in agreement with optically thick emission. All lightcurves show strong variability on all time scales. Analyzing the time lags between the lightcurves from different frequency bands, we find that we can distinguish high-peaking flares and low-peaking flares in accord with the classification of Valtaoja et al. (1992). The periodograms (temporal power spectra) of the observed lightcurves are consistent with random-walk powerlaw noise without any indication of (quasi-)periodic variability. The fact that all four sources studied are in agreement with being random-walk noise emitters at radio wavelengths suggests that such behavior is a general property of blazars.

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