• Title/Summary/Keyword: Carbon Balance

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Effect of Initial Glucose Concentrations on Carbon and Energy Balances in Hydrogen-Producing Clostridium tyrobutyricum JM1

  • Jo, Ji-Hye;Lee, Dae-Sung;Kim, Jun-Hoon;Park, Jong-Moon
    • Journal of Microbiology and Biotechnology
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    • v.19 no.3
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    • pp.291-298
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    • 2009
  • The carbon metabolism of newly isolated Clostridium tyrobutyricum JM1 was investigated at varying initial glucose concentrations (27.8-333.6mM). Because an understanding of metabolic regulations was required to provide guidance for further effective metabolic design or optimization, in this case, maximizing hydrogen production, carbon and energy balances by C. tyrobutyricum JM1 were determined and applied in anaerobic glucose metabolism. The overall carbon distribution suggested that initial glucose concentrations had strong influence on the stoichiometric coefficients of products and the molar production of ATP on the formation of biomass. C. tyrobutyricum JM1 had a high capacity for hydrogen production at the initial glucose concentration of 222.4 mM with high concentrations of acetate and butyrate.

Boiler Performance Characteristics Change by UC Contents Increase for Coal Fired Power Plant (석탄연소 화력발전소에서 미연탄소분 농도 증가가 보일러 성능에 미치는 영향에 관한 연구)

  • Kim, Taehyung;Park, Byungchul
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.99-102
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    • 2015
  • To operate coal fired power plant efficiently is considered unburned carbon as important factor. But, unburned carbon contents change does not have an impact on Boiler performance simultaneously. we evaluated that unburned carbon contents change had an little influence on unburned carbon loss change for performance side at a real power plant.

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A Study on Heat and Mass Balance in a Coal Gasifier (석탄 가스화기 열 및 물질정산에 관한 연구)

  • Kim, Bong-Keun;Yoo, Jeong-Seok;Kim, You-Seok
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.424-428
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    • 2007
  • In the current most tool using heat and mass balance in a coal gasifier is dependent on commercial code such as STANJAN, CHEMKIN. However, in order to keep the self-reliance technology, it is necessary to develop the original design tool available for comprehension and analysis on the spot. So in this study, its own heat and mass balance program is developed on the assumption that the process in a coal gasifier is adiabatic and quasi-equilibrium. The mass balance is calculated by using the chemical equilibrium principle. Also the heat and mass balance according to main operating factors such as temperature, pressure and O2/Coal ratio, was carried in this tool. This heat and mass balance was verified on the basis of the results simulated in STANJAN, commercial codes using similar logic.

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Characterizing Spatiotemporal Variations and Mass Balance of CO2 in a Stratified Reservoir using CE-QUAL-W2 (CE-QUAL-W2를 이용한 성층 저수지에서 CO2의 시공간적 분포 및 물질수지 분석)

  • Park, Hyungseok;Chung, Sewoong
    • Journal of Korean Society on Water Environment
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    • v.36 no.6
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    • pp.508-520
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    • 2020
  • Dam reservoirs have been reported to contribute significantly to global carbon emissions, but unlike natural lakes, there is considerable uncertainty in calculating carbon emissions due to the complex of emission pathways. In particular, the method of calculating carbon dioxide (CO2) net atmospheric flux (NAF) based on a simple gas exchange theory from sporadic data has limitations in explaining the spatiotemporal variations in the CO2 flux in stratified reservoirs. This study was aimed to analyze the spatial and temporal CO2 distribution and mass balance in Daecheong Reservoir, located in the mid-latitude monsoon climate zone, by applying a two-dimensional hydrodynamic and water quality model (CE-QUAL-W2). Simulation results showed that the Daecheong Reservoir is a heterotrophic system in which CO2 is supersaturated as a whole and releases CO2 to the atmosphere. Spatially, CO2 emissions were greater in the lacustrine zone than in the riverine and transition zones. In terms of time, CO2 emissions changed dynamically according to the temporal stratification structure of the reservoir and temporal variations of algae biomass. CO2 emissions were greater at night than during the day and were seasonally greatest in winter. The CO2 NAF calculated by the CE-QUAL-W2 model and the gas exchange theory showed a similar range, but there was a difference in the point of occurrence of the peak value. The findings provide useful information to improve the quantification of CO2 emissions from reservoirs. In order to reduce the uncertainty in the estimation of reservoir carbon emissions, more precise monitoring in time and space is required.

Nonlinear vibration properties of a zigzag single-walled carbon nanotube embedded in a polymer matrix

  • Besseghier, Abderrahmane;Heireche, Houari;Bousahla, Abdelmoumen Anis;Tounsi, Abdelouahed;Benzair, Abdelnour
    • Advances in nano research
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    • v.3 no.1
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    • pp.29-37
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    • 2015
  • In the current study, the nonlinear vibration properties of an embedded zigzag single-walled carbon nanotube (SWCNT) are investigated. Winkler-type model is used to simulate the interaction of the zigzag SWCNTs with a surrounding elastic medium. The relation between deflection amplitudes and resonant frequencies of the SWCNT is derived through harmonic balance method. The equivalent Young's modulus and shear modulus for zigzag SWCNT are derived using an energy-equivalent model. The amplitude - frequency curves for large-amplitude vibrations are graphically illustrated. The simulation results show that the chirality of zigzag carbon nanolube as well as surrounding elastic medium play more important roles in the nonlinear vibration of the single-walled carbon nanotubes.

The Study on the improvement of vehicle fuel economy test method according to the characteristics of test fuel (시험용 연료 특성에 따른 자동차 연비측정 방법 개선에 관한 연구)

  • Lee, Minho;Kim, Jeonghwan
    • Journal of Energy Engineering
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    • v.23 no.4
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    • pp.9-18
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    • 2014
  • These test methods, the current domestic vehicles fuel economy calculation method is tested on a dynamometer for vehicles after you have installed the vehicle, given the test mode(FTP-75 & HWFET mode, etc.) are measured by vehicle emissions and fuel economy by seeking to have the results approach, the carbon balance method. At this point, using the carbon balance method is a test method was developed seeking fuel for a standard fuel properties, where the value of the constant and saved test was measured in THC, CO, $CO_2$ has a value calculation. Therefore, use fuel which is changed every time you test the fuel properties characteristics are not considered exactly. In this study, using the carbon balance method and fluid flow rate of the fuel used in the actual test is measured by comparing the results with the flow measurement methods, properties of the fuel used for the test attribute to study ways that can be considered, taking into account the physical attributes of a more diverse fuel line and fuel economy improved measurement methods that can be reviewed.

EFFECTS OF NICARBAZIN AND HOT TEMPERATURE ON EVAPORATIVE WATER LOSS, ACID-BASE BALANCE, BODY TEMPERATURE AND CARBON DIOXIDE EXHALATION IN ADULT ROOSTERS

  • Lee, B.D.;Lee, S.K.;Hyun, W.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.1
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    • pp.97-101
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    • 1994
  • Two experiments were conducted to study the effect of ambient temperature and nicarbazin on SCWL adult roosters. In Experiment 1, the effects of nicarbazin supplementation (125 ppm) on the water metabolism, blood acid-base balance; and rectal temperature of 16 birds in normal ($21^{\circ}C$) and hot ($35-36^{\circ}C$) temperature were investigated. In Experiment 2, the evaporative water loss and $CO_2$ exhalation from 8 birds were measured individually with an open-circuit gravimetric respiration apparatus in normal ($21^{\circ}C$) and hot ($33.5-34^{\circ}C$) temperature. The amount of water intake and evaporative water loss increased in birds under heat stress (HS). Nicarbazin exacerbated these effect in hot temperature. Also, nicarbazin decreased the blood $pCO_2$ and increased pH of HS birds. The rectal temperature of birds increased in hot temperature, and nicarbazin worsened this effect. The evaporative water loss, measured directly with respiration apparatus (Experiment 2), was increased in hot temperature. HS decreased the amount of $CO_2$ exhalation. Nicarbazin did not exert ant effect on either of these measurements, probably due to the limited duration (2 h) of the trial. The decrease in $CO_2$ exhalation by HS birds could be explained by reduced metabolic rate, which helps homeothermy of birds in hot temperature.

Evaluation of Carbon Balance for Carbon Sink/Emission with Different Treatments in Paddy Field (벼논에서 양분관리별 탄소의 흡수·배출에 대한 탄소수지 평가)

  • Kim, Gun-Yeob;Lee, Jong-Sik;Lee, Sun-Il;Jeong, Hyun-Cheol;Choi, Eun-Jung;Na, Un-sung
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.715-725
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    • 2017
  • Importance of climate change and its impact on agriculture and environment has increased with the rise in the levels of Green House Gases (GHGs) in the atmosphere. To slow down the speed of climate change, numerous efforts have been applied in industrial sectors to reduce GHGs emission and to enhance carbon storage. In the agricultural sector, several types of research have been performed with emphasis on GHGs emission reduction; however, only a few work has been done in understanding the role of carbon sink on reduction in GHGs emission. In this study, we investigated ecosystem carbon balance and soil carbon storage in an agricultural paddy field. The results obtained were as follows: 1) Evaluation of soil C sequestration in paddy field was average $3.88Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, average $3.22Mg\;C\;ha^{-1}$ following NPK+hairy vetch treatment, and average $1.97Mg\;CO_2\;ha^{-1}$ following NPK treatment; and 2) Net ecosystem production (NEP) during the paddy growing season was average $14.01Mg\;CO_2\;ha^{-1}$ following NPK+hairy vetch treatment, average $12.60Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, and average $11.31Mg\;CO_2\;ha^{-1}$ following NPK treatment. Therefore, it is proposed that organic matter treatment can lead to an increase in soil organic carbon accumulation and carbon sock of crop ecosystem in fields compared to chemical fertilizers.

Effect of Level of Leucaena leucocephala in the Diets of Jamunapari Goats on carbon Nitrogen and Energy Balances

  • Haque, N.;Khan, M.Y.;Murarilal, Murarilal
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.5
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    • pp.455-459
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    • 1997
  • Fifteen intact male Jamunapari goats, average body weight $22.0{\pm}1.18kg$ were divided into three groups of 5 animals in each to investigate the effects of feeding leucaena on energy retention and distribution of retained energy. Leucaena leaves and twigs provided 0%, 25% and 50% of CP in the rations of animals in $L_1$ (control), $L_2$ and $L_3$ groups, respectively. Energy balances were determined in an open circuit respiration chamber from gaseous exchange and nitrogen carbon balances. Energy retentions calculated from gaseous exchange data were 181.6, 190.0 and 172.8 kJ/kg $W^{0.75}/d$ and from carbon-nitrogen balances were 178.2, 199.5 and 171.1 kJ/kg $W^{0.75}/d$ in $L_1$, $L_2$ and $L_3$ groups, respectively. No significant difference was observed among the groups in both the methods. The retention of nitrogen and energy in the form of protein was similar in different treatment groups. Similarly, no significant effect was observed on energy retention in the form of fat and total energy retention due to incorporation of leucaena in the diets.