• 제목/요약/키워드: Li excess

검색결과 92건 처리시간 0.024초

정적연소기에서의 메탄-공기 혼합기의 연소특성(3) : 배기배출물 (Combustion Characteristics of Methane-Air Mixture in a Constant Volume Combustion Chamber(3) : Exhaust Emission)

  • 최승환;전충환;장영준
    • 한국자동차공학회논문집
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    • 제12권2호
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    • pp.1-8
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    • 2004
  • A cylindrical constant volume combustion chamber was used to investigate the exhaust emission characteristics of homogeneous charge, stratified pattern and inhomogeneous charge under various conditions using gas chromatography. In the case of homogeneous charge condition, the $CO_2$ concentration is proportional to excess air ratio and overall charge pressure, the $CO_2$ concentration is proportional to excess air ratio and the UHC concentration is inversely proportional to ignition time and overall charge pressure. In the case of stratified pattern, the RI(rich injection) condition shows better exhaust emission characteristics, especially $CO_2$, than that of HI (homogeneous injection) or LI (lean injection) conditions. In inhomogeneous charge conditions, when initial charge pressure is increased, $CO_2$ and UHC concentration is reduced but $O_2$ concentration is increased. And when the excess air ratio of initial charge mixture is 3.0, UHC and $CO_2$concentration show lowest values.

RGB 컬러 이미지를 이용한 콩의 군락 피복과 엽면적에 대한 저비용 평가 (Low-cost Assessment of Canopy Light Interception and Leaf Area in Soybean Canopy Cover using RGB Color Images)

  • 이윤호;상완규;백재경;김준환;조정일;서명철
    • 한국농림기상학회지
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    • 제22권1호
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    • pp.13-19
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    • 2020
  • 본 연구는 저비용·저 노동력을 위해 RGB 컬러 이미지에서 획득한 녹색영역 값과 엽면적 그리고 군락피복 측정을 비교하였다. 시험에 사용된 품종은 국내에서 가장 많이 재배되고 있는 대원콩, 대풍콩 및 풍산나물콩을 재배하였다. 측정 시기는 엽의 4.5엽기부터 종실비대기까지 RGB 컬러 이미지를 획득하여 군락 엽면적과 피복을 비교하였다. 이미지 분석은 ExGR로 토양으로부터 식물체의 녹색 영역을 분리하였다. 분리한 녹색 영역과 실제 측정한 엽면적과 피복과는 고도의 유의성을 보였다. 본 연구 결과에서 알 수 있듯이 실제 측정한 군락 엽면적과 군락 피복과는 정의 상관관계(r2=0.84)를 보였다. 군락 이미지와 실제 측정한 군락 피복과는 고도의 정의상관관계(r2=0.94)를 보였다. 또한 군락 이미지와 실제 측정한 군락 엽면적과는 고도의 정의상관관계(r2=0.74)를 보였다. 따라서 향후 RGB 컬러 이미지로 저비용·저 노동력으로 군락 단위에서 엽면적과 피복을 손쉽게 측정할 수 있을 것으로 기대된다.

열분석법에 의한 Al-2.1Li-2.9Cu합금의 석출현상(I) - 석출순서 - (The Precipitation Phenomena of Al-2.1Li-2.9Cu alloy by Differential Scanning Calorimetry(I) - Precipitation sequence -)

  • 박태원
    • 열처리공학회지
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    • 제9권4호
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    • pp.252-260
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    • 1996
  • A study was conducted to examine the precipitation phenomena of Al-2.1Li-2.9Cu alloy by differential scanning calorimetry and transmission electron microscopy. DSC curves were measured over the temperature range of $25{\sim}550^{\circ}C$ at a heating rate of $2{\sim}20^{\circ}C$/min.. Three heat evolution peaks and three heat absorption peaks were observed in the DSC curve for the as-quenched specimen. From DSC results and TEM analysis, it was proved that the precipitation sequence in the as-quenched specimen is supersaturated solid solution ${\rightarrow}$ GP zone ${\rightarrow}{\delta}^{\prime}{\rightarrow}T_1{\rightarrow}T_2$ and ${\theta}^{\prime}$ was detected in the peak aged specimen at $160^{\circ}C$. The major phase formed at peak hardeness in the aging at $160^{\circ}C$ was ${\delta}^{\prime}$ phase. The activation energies for the formation of ${\delta}^{\prime}$ and $T_1$ phases were 22.3kcal/mole and 24.3kcal/mole, respectively. These lower activation energies than those for diffusion of Cu and Li in Al are ascribed to the quenched-in excess vacancies.

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$LiNbo_3$의 음향광학효과와 음향파 장벽을 이용한 편광모드 변환형, 파장가변 광 필터에 관한 연구 (A study of polarized mode convertible, wavelength tunable optical filter utilizing acoustic barrier and acouxto-optic effect in $LiNbo_3$)

  • 임경훈;정홍식
    • 한국광학회지
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    • 제11권3호
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    • pp.193-197
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    • 2000
  • 음향파 장벽 구조와 음향광학효과를 이용한 편광모드 변환형 파장가변 광 필터를 LiNbo3와 Ti 이중 확산 공정 기술을 이용하여 제작하였다. 1552.6nm 파장의 TE, TM 입사 편광모드에 대해서 173.07MHz, 173.05MHz의 Rf 주파수에서 81% 이상의 변환효율과 ∼200kHz(∼1.83nm)의 통과대역폭을 얻어Tdmaum 구동파워는 10.97mW로서 음향파 장벽이 없는 광 필터 파워의 10%에 불과 하였다. 파장 변화율과 부 모드 레벨리 각각 8.2nm/MHz와 -4dB로 측정하였다.

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Fe-LiNbO$_{3}$ 결정에서 광굴절격자의 비균일성에 의한 광학적 잡음의 영향 분석 (Analysis of optical noise influence due to inhomogeneity of photorefractive grating in Fe-LiNbO$_{3}$ crystal)

  • 안준원;최연숙;김남;이권연;강석열
    • 전자공학회논문지D
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    • 제35D권3호
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    • pp.91-97
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    • 1998
  • In a LiNbO$_{3}$ crystal, optical noise is caused by the inhomogeneity of crystal inside if the excess energy is incident on the crystal. In this paper, we experiemnt the influence of optical noise when it is applied for beam diffraction and optical information storage. And it is proposed the energy threshold level which is not affected by optical noise in Fe-LiNbO$_{3}$ crystal(0.02Wt.% doped, 10mm*10mm*10mm). The optical noise of crystal weremeasured as a function of the incident beam intensity(10mw, 5mw, 1mw, 0.5mw), direction in incident(orthogonal, left rotation, right rotation) and wavelength(514.5nm, 632.8nm).

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장개빈(張介賓) 울증론치(鬱證論治) 연구 (Zhang Jiebin(張介賓)'s Discussion and Treatment of the Depressive Pattern)

  • 裵靚耘;朴基鎬;柳姃我
    • 대한한의학원전학회지
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    • 제35권4호
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    • pp.77-96
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    • 2022
  • Objectives : This paper examines the medical treatise and treatment methods of Zhang Jiebin on the depressive pattern, for clinical application today. Methods : The Zazhengmo/Yuzheng chapter of the Jingyue Quanshu, related texts and annotations of the Huangdineijing, and related contents among the medical texts of the JinYuan masters were analyzed. Developmental process of the medical theories were compared and examined. Results : Zhang focused on the mechanism in which emotion affects Qi leading to a disease state, and categorized Yu[鬱, depressed state] into three: anger depression, contemplative depression and comprehensive depression. The concept of the Five Depressive Patterns and its treatment from the Huangdineijing·Suwen which was considered as excess pattern was expanded to include deficiency pattern based on comparison with annotations of Wangbing, Hwashou, and Wang Andao. Treatment methods centered on purging was also expanded to include tonifying to restore the damaged Jing Qi. The depressive patterns anger depression, contemplative depression and comprehensive depression were subdivided according to excess and deficiency, for which formulas such as Shenxiangsan, Shoupijian, Guipitang were suggested. As the depressive pattern is caused by emotions and thus the Heart, the Yiqingbianqi method that directly deals with emotions was suggested. Zhang adopted Zhu Zhenheng's opinion which expands the category of Yu, and in the perspective of excess/deficiency, it is most similar to that of Li Dongyuan. Conclusions : Before Zhang, the depressive pattern was discussed in terms of it being excess pattern. However, Zhang's discussion on depressive pattern based on anger depression, contemplative depression and comprehensive depression focuses on emotional stagnation while suggesting the possibility of deficient stagnation, expanding previous understanding. In terms of treatment, tonifying methods for deficiency pattern was added, while consideration of emotion itself became necessary in treatment.

국산 고령토로 합성한 제올라이트 A의 이온교환성 (The Ion-Exchange Properties of Synthetic Zeolite A from Domestic Kaolin)

  • 김영대;김면섭
    • 한국세라믹학회지
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    • 제18권2호
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    • pp.91-98
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    • 1981
  • Synthetic zeolite A was prerared from domestic Hadong kaolin with sodium hydroxide solution and their ion exchange isotherms of $K^+$, $NH^{4+}$, $Li^+$ and $Ag^+$ ion were presented. The optimum reaction conditions for synthetic zeolite A from calcinated kaolin were 2 fold excess of 2N sodium hydroxide solution, 10$0^{\circ}C$ and 8 hours. It was observed that before the crystallization of zeolite A the samples reacted with sodium hydroxide solution had rather higher ion exchange capacities than zeolite A. The $K^+$-$Na^+$ and $Ag^+$$Na^+$ ion exchange isotherms were signoidal. The initial selectivity series was in the order $Ag^+$$K^+$>$Na^+$>$NH_4$>$Li^+$. Between approximately 33 and 67% replacement of soium ions the selectivity series became $Na^>$ and above 67% became $Ag^+$>$K^+$. Evidence were also presented to demonstrate that 8 out of 12 sodium ions per pseudo unit cell were not easily replaceable by lithium ions and 4 out of 12 not easily replaceable by ammonium ions.

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운동 강도의 차이가 제2형 당뇨병 환자와 비만인의 초과산소 섭취량, 안정 시 대사량 및 생화학적 변인에 미치는 영향 (Effects of Different Exercise Intensity on Excess Post Exercise Oxygen Consumption (EPOC), Resting Metabolic Rate (RMR), and Biochemical Variables in Obese and NIDDM Patients)

  • 곽이섭;구우영;유병인;진영완;최경석;조준용;우진희;황혜진
    • 생명과학회지
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    • 제18권10호
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    • pp.1455-1463
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    • 2008
  • The purpose of this study was to evaluate the effect of various exercise intensity on Excess post exercise energy expenditure (EPEE), Resting Metabolic Rate (RMR),thyroid hormonal changes and biochemical variables in obese and NIDDM patients. The subject of the present study were divided into four groups and four periods: trained (T; n=10), control (C; n=10), obese (O; n=10) and NIDDM (N; n=10) group. And the periods were divided as follows; Resting (RE), Maximal (MA), High intensity (HI), and Low intensity (LI). There was significant difference in RMR among different intensity of exercise. in the T (p<0.05) not in the C, O, and N groups. however, there was no significant different percent body fat among all groups. In the energy expenditure, there was significant different among C, O, N groups compare to T in HIEE (high intensity exercise energy expenditure), LIEE (low intensity exercise energy expenditure), HIEEPE (high intensity exercise energy expenditure post exercise) and LIEEPE (low intensity exercise expenditure post exercise). In the hormonal level, there was significant different in T4 level in the T group at LI period and there was also significant difference in T4, Free T3, & Free T4 levels in T group at LI period, however there was no significant different in the O and N groups except LI period. In the fatigue variables, there was significant different in lactate and ammonia levels in the N group in the period of HI compare to C. The present cross-sectional study was design to investigate the relationship between exercise intensity and RMR in four groups. The focus of this investigation was to compare RMR in aerobically trained (T), control (C), obese (O) and NIDDM (N) group. The relationship among RMR, exercise intensity and percent body fat would best be investigated using Meta Lyzer 3B, MMX3B and body composition analyzer. Each subject completed measurement of percent body fat, RMR, hormone in the period of maximal oxygen uptake exercise (MA), high intensity exercise (HI), and low intensity exercise (LI). From the results, High and Low intensity of exercise, there was a trend for an increased RMR (kcal/day) in the trained groups and control group (in case of LI) not for the obese and N groups. This is best explained not by the reduced percent body fat but by the highly induced energy expenditure (during exercise and post exercise energy expenditure) and increased T4, Free T3, and Free T4 hormonal levels in the low intensity exercise for the T group and sometimes C group.

Low-Firing Pb(Zr,Ti)O3-Based Multilayer Ceramic Actuators Using Ag Inner Electrode

  • Han, Hyoung-Su;Park, Eon-Cheol;Lee, Jae-Shin;Yoon, Jong-Il;Ahn, Kyoung-Kwan
    • Transactions on Electrical and Electronic Materials
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    • 제12권6호
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    • pp.249-252
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    • 2011
  • We investigated the low firing of $Li_2CO_3$ added $0.2Pb(Mg_{1/3}Nb_{2/3})O_3$ - 0.3Pb($Fe_{1/2}Nb_{1/2}$) - $0.5Pb(Zr_{0.475}Ti_{0.525})O_3$ (PMN-PFN-PZT) ceramics and multilayer actuators (MLAs) using Ag inner electrodes. It was found that 0.1 wt% $Li_2CO_3$ was quite effective in lowering the sintering temperature of PMN-PFN-PZT ceramics from $1,100^{\circ}C$ down to $900^{\circ}C$ without deteriorating their piezoelectric ceramics ($d_{33}$ = 425 pC/N and $k_p$ = 61.9%). However, excess $Li_2CO_3$ up to 0.3 wt% brings about unwanted problems such as the formation of a $LiPbO_2$ secondary phase and subsequent degradation in the piezoelectric properties. Using 0.1 wt% $Li_2CO_3$ added PMN-PFN-PZT ceramics, MLAs with Ag inner electrodes were successfully fabricated, resulting in a normalized strain of 580 pm/V at an electric field of 1.5 kV/mm.