• Title/Summary/Keyword: excess energy

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Theoretical Studies of Solvent Effects on Gas Phase Reactions of Methoxide Ion with Substituted Ethylenes$^\dag$

  • Lee, Ik-Choon;Lee, Bon-Su;Won Jong-Ok
    • Bulletin of the Korean Chemical Society
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    • v.8 no.6
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    • pp.444-449
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    • 1987
  • Solvent effects on gas phase reactions of methoxide ion with substituted ethylenes, $CH_2$ = CHR where R = CN, CHO and $NO_2$, are investigated theoretically using the AM1 method. Results show that the methoxide approaches in-plane in all reactions, but subsequently rotate out-of-plane to form tetrahedral complexes in additon reactions. All reactions of a bare methoxide are found to be exothermic, the exothermicity being the greatest in the ${\beta}$-addition, in which the excess energy is forced to be contained within the ${\beta}$-adduct rendering extreme instability. However a part of the excess energy can be removed by a solvate molecule giving a stable complex prior to the product formation. The hydride transfer processes were found to be unfavorable due to the high activation barriers. The ${\alpha}-H^+$ abstraction process from acrylonitrile becomes endothermic as a result of monosolvation of the methoxide, in agreement with experimental results.

Treatments of Infantile Diseases in Hyungsang Medicine (소아질환의 형상의학적 치료)

  • Jung, Haeng-Gyu;Kang, Kyung-Hwa;Lee, Yong-Tae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.2
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    • pp.561-566
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    • 2007
  • After researching on infantile diseases in Hyungsang medicine, the writer got the conclusions as follows. The infants who are excess of the Yang energy need to nourish the Eum- blood. The main causes of the infantile disorders are congenital defect and malfunction of internal organs by nature, as results of these they suffer from mental disorders or being undergrown. And after birth they get ill from internal injury or external affections, mainly epilepsy by retention of undigested food, fever, cough, asthma, nasal obstruction, dermatopathia, and affection by cold, etc. In Hyungsang medicine Dam-body is apt to get ill from deficiency of Eum-blood and bangkwang-body from deficiency of Yang-energy. And infants are hare to be moderate in food, so they become to diseases of the Spleen and stomach, especially infants with Yangmyung type get to epilepsy, cough, skin disorders, and obese for the reasonof overeating. Among main infantile symptoms congenital defects, infantile mental disorders, and convulsive diseases come from congenital defect and malfunciton of internal organs, so it must be treated the symptoms following the reasons. Above all infantile mental disorders are treated not to separate the spirit from the body. And fever, cough and asthma, affection by cold, skin diseases, poor appetite, and obese come from deficiency of Kidney or the deficiency and excess of the Spleen and stomach. In order to prevent from infantile diseases right antenatal training, taking medicine rightly, exercise and eating good habits are needed to give guidance. Seeing through the clinical cases in Hyungsang medicine, we come to know that the infantile mental disorders come out primarily for the reasons of the congenital defect, and the infantile epilepsy come from malfunction of internal organs, and the nasal obstruction and skin diseases come from deficiency of Kidney or the deficiency and excess of the Spleen and stomach.

The Economic Feasibility Analysis of 100-MW Power-to-Gas System (100 MW급 Power-to-Gas 시스템의 사전 경제성 분석)

  • Ko, Areum;Park, Sung-Ho;Kim, Suhyun
    • Clean Technology
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    • v.26 no.1
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    • pp.55-64
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    • 2020
  • According to the Korean Renewable Energy 3020 Implementation Plan, the installation capacity of renewable energy is expected to increase whereas technology for storing excess electricity and stabilizing the power supply of renewable energy sources is extremely required. Power-to-Gas is one of energy storage technologies where electricity is converted into gas fuel such as hydrogen and methane. Basically, Power-to-Gas system could be effectively utilized to store excess electricity generated by an imbalance between supply and demand. In this study, the economic feasibility analysis of Power-to-Gas reflecting the domestic situation was carried out. Total revenue requirement method was utilized to estimate the levelized cost of hydrogen. Validation on the economic analysis method in this study was conducted by comparison of the result, which is published by the International Energy Agency. The levelized cost of hydrogen of a 100-MW Power-to-Gas system reflecting the current economic status in Korea is 8,344 won kg-1. The sensitivity analysis was carried out, applying the main analysis economic factors such as electricity cost, electrolyser cost, and operating year. Based on the sensitivity analysis, the conditions for economic feasibility were suggested by comparing the cost of producing hydrogen using renewable energy with the cost of producing natural gas reformed hydrogen with carbon capture and storage.

Estrogen deprivation and excess energy supply accelerate 7,12-dimethylbenz(a)anthracene-induced mammary tumor growth in C3H/HeN mice

  • Kim, Jin;Lee, Yoon Hee;Yoon Park, Jung Han;Sung, Mi-Kyung
    • Nutrition Research and Practice
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    • v.9 no.6
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    • pp.628-636
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    • 2015
  • BACKGROUND/OBJECTIVES: Obesity is a risk factor of breast cancer in postmenopausal women. Estrogen deprivation has been suggested to cause alteration of lipid metabolism thereby creating a cellular microenvironment favoring tumor growth. The aim of this study is to investigate the effects of estrogen depletion in combination with excess energy supply on breast tumor development. MATERIALS/METHODS: Ovariectomized (OVX) or sham-operated C3H/HeN mice at 4 wks were provided with either a normal diet or a high-fat diet (HD) for 16 weeks. Breast tumors were induced by administration of 7,12-dimethylbenz(a)anthracene once a week for six consecutive weeks. RESULTS: Study results showed higher serum concentrations of free fatty acids and insulin in the OVX+HD group compared to other groups. The average tumor volume was significantly larger in OVX+HD animals than in other groups. Expressions of mammary tumor insulin receptor and mammalian target of rapamycin proteins as well as the ratio of pAKT/AKT were significantly increased, while pAMPK/AMPK was decreased in OVX+HD animals compared to the sham-operated groups. Higher relative expression of liver fatty acid synthase mRNA was observed in OVX+HD mice compared with other groups. CONCLUSIONS: These results suggest that excess energy supply affects the accelerated mammary tumor growth in estrogen deprived mice.

Comparison of excess post-exercise oxygen consumption of different exercises in normal weight obesity women

  • Jung, Won-Sang;Hwang, Hyejung;Kim, Jisu;Park, Hun-Young;Lim, Kiwon
    • Korean Journal of Exercise Nutrition
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    • v.23 no.2
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    • pp.22-27
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    • 2019
  • [Purpose] The purpose of this study was to compare the excess post-exercise oxygen consumption (EPOC) between different types of exercises in women with normal weight obesity (NWO). [Methods] Nine university students with NWO having body mass index <25 kg/m2 and body fat percentage >30% participated in the study. First, continuous exercise (CEx) on an ergometer for 30 minutes at 60% of maximal oxygen consumption (VO2max) and interval exercise (IEx) at 80% VO2max for 2 minutes were performed. This was followed by exercise performed at 40% VO2max for 1 minute and at 80% VO2max for 3 minutes, performed 6 times repeatedly for a total of 26 minutes. The accumulation of short duration exercise (AEx) was performed for 3-bouts of 10 minutes each at 60% VO2max. [Results] The major findings were as follows: energy consumption during the exercises showed no significant difference between CEx, IEx, and AEx; EPOC was higher in IEx and AEx as compared to CEx for all dependent variables (e.g. total oxygen consumption, total calorie, summation of heart rate, and EPOC duration); and the lipid profile showed no significant difference. [Conclusions] Our study confirmed that when homogenizing the energy expenditure for various exercises in NWO individuals, EPOC was higher in IEx and AEx than in CEx. Therefore, IEx and AEx can be considered as effective exercise methods for increasing energy expenditure in NWO females.

Measurement and Calculation of Excess Enthalpies for n-Hexane/Alkane series and NaOH/Water/Ethanol System using Isothermal Microcalorimeter (등온 미세열량계를 이용한 n-Hexane-알칸계 이성분 혼합물 및 NaOH/Water/Ethanol계의 과잉 엔탈피 측정 및 계산)

  • Choi, In Kyu;You, Seong-sik
    • Korean Chemical Engineering Research
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    • v.55 no.5
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    • pp.660-667
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    • 2017
  • Equilibrium data of the mixture is essential in the design and operation of separation equipment such as distillation or extraction in chemical processes. These equilibrium data can be obtained through experiments or by calculations using the known binary parameters and the thermodynamic models. Generally, to obtain these parameters, phase equilibrium experimental data such as gas-liquid and liquid-liquid are used. In this study, the excess enthalpy of the mixture was measured using the flow type microcalorimeter which is a simpler method than phase equilibria experiments, and the parameters of various theories were obtained by using this data. In order to investigate the relationship between carbon chain length, enthalpy and binary parameters in the alkane system, excess enthalpies for the n-hexane + alkane (n-pentane, n-heptane, n-octane and n-dodecane) were measured at 298.15 K and the banary interaction parameters of Wilson, NRTL, and UNIQUAC were obtained from the experimental data. In addition, we wanted to obtain basic information on the interaction and association phenomena of the system including electrolyte applicable to various fields by using the excess enthalpy experimental data and the existing theory. First, we investigated the excess enthalpy for the NaOH / Water / Ethanol system as a basic experiment and examined the applicability using the electrolyte-NRTL (eNRTL) theory.

The Effects of Solvent Composition and Pressure on the Rate of Solvolysis of trans-$[Co(en)_2Cl_2]^+$, trans-$[Co(N-eten)_2Cl-2]^+$, trans-$[Co(N-meen)_2Cl-2]^+$ and trans-$[Co(tn)_2Cl-2]^+$ in Aceton-Water Mixture. Excess Free Energy & Free Energy Cycle and Reaction Mechanism (아세톤-물 혼합용매에서 trans-$[Co(en)_2Cl-2]^+$, trans-$[Co(N-eten)_2Cl-2]^+$, trans-$[Co(N-meen)_2Cl_2]^+$, trans-$[Co(tn)_2Cl_2]^+$ 착이온의 가용매 분해반응에 대한 압력과 용매조성의 영향. 반응메카니즘과 자유에너지 변화사이클 및 Excess 자유에너지)

  • Yu-Chul Park;Young-Je Cho
    • Journal of the Korean Chemical Society
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    • v.29 no.6
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    • pp.629-636
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    • 1985
  • The rates of solvolysis of trans-$[Co(AA)_2Cl_2]^+$ in which AA indicates ethylenediamine(en), N-ethylethylenediamine (N-eten), N-methylethylenediamino (N-meen) and trimethylenediamine(tn) respectively have been investigated using conductometric and spectrophotometric methods at various pressure up to 2,000 bar in acetone-water mixture. The activation volumes (${\Delta}V^{\neq}) obtained from the pressure effect on rate constants were -0.2∼0.9 $cm^3mole^{-1}$ for en, -0.2∼0.6 $cm^3mole^{-1}$ for N-eten, -0.8∼6.0 $cm^3mole^{-1}$ for N-meen and 0.7∼7.0$cm^3mole^{-1}$ for tn. The rates of solvolysis of these complexes were analyzed by comparing with the results obtained from excess free energy ($G^E$) and free energy cycle. It was found that $S_N1$ character was increased with decreasing the pressure and increasing the content of acetone in the mixture solvent. In addition to that, the effect of charge separation on the mechanism of solvolysis was discussed.

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A Study on Effect of Applying Energy Storage System on SeoulMetro Line 2 (에너지저장시스템의 서울메트로 2호선 적용 효과에 관한 연구)

  • An, Cheon-Heon;Lee, Han-Min;Kim, Gil-Dong;Lee, Hi-Sung
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.966-971
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    • 2009
  • The recent environmental protection trend requires more strict energy saving, therefore every transportation system should reduce energy consumption to the minimum value. High-efficiency operation system, energy saving and CO2 emissions shall be addressed as important issue in railway system. These issues are the most essential factors of railway, compared to major public transportation system. Recently, saving energy in the electric railway system has been studied. For such new energy saving, the Energy storage system is considered for saving energy. Energy saving is possible by efficient use of regenerated energy. Regenerated energy is recycled amongst vehicles by mean of charge and discharge corresponding to powering and braking of electric vehicle operations. This energy saving contributes to cut CO2 to reduce greenhouse gas emissions. Recycling regenerated energy demonstrate significant effect on peak cut of consumption energy in railway substation. Absorption of excess energy avoids regeneration failure due to high traction voltage. This paper presents effects by applying the energy storage system to SeoulMetro Line 2.

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A Study on the Hydrogenation Properties of MmNi4.5Al0.5Zrx(X=0.0-0.2) Alloys Containing the Zr by Excess (Zr을 과잉 첨가한 MmNi4.5Al0.5Zrx(X=0.0-0.2) 합금의 수소화 반응특성에 대한 연구)

  • Na, Young-Sang;Lee, Jai-Young
    • Transactions of the Korean hydrogen and new energy society
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    • v.4 no.1
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    • pp.31-39
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    • 1993
  • In order to improve the hydrogen storage capacity and the activation property of the $MmNi_{4.5}Al_{0.5}$ alloy, the multiphase alloy system are prepared by adding the excess Zr in $MmNi_{4.5}Al_{0.5}$ alloy. It is estimated from the X-ray diffraction pattern and the energy dispersive X-ray analysis that the 2nd phases in $MmNi_{4.5}Al_{0.5}Zr_x$ alloys are $ZrNi_3$, ${\beta}$-Zr. Their morphology is also examined by the scanning electron microscope, and it shows the needle-like precipitation. As the Zr contents increase, the activation time and the plateau pressure decrease, sloping of the plateau pressure increase. Amount of the 2nd phases increase with Zr contents in $MmNi_44.5Al_{0.5}Zr_x$ alloys. The $MmNi_44.5Al_{0.5}Zr_{0.05}$ alloy, which shows the maximum storage capacity and the strong resistance to intrinsic degradation, is considered as a proper alloy for hydrogen storage.

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