• Wind and Structures
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• v.20 no.1
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• pp.1-13
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• 2015

This study applied long-term wind speed data from Penghu and Dongjidao weather stations to simulate the wind energy production for eight onshore and one offshore wind farms at Penghu Island, Taiwan by a commercial software package, Wind Atlas Application Program (WAsP). In addition, the RET Screen software suite was also applied to analyze economic characteristics of these nine wind farms (WFs). The results show that the capacity factors (CFs) of the nine wind farms mentioned above are in the range of 44.5% to 49.1%. In addition, utilizing 1.8-MW wind turbines (WTs) for all onshore WFs was the most feasible selection among the four potential types of WTs (600, 900, 1,800 and 3,600 kW) considered. 3-MW WTs selected for the offshore WF can produce the most wind energy and the smallest wake loss among the three possible types of WTs (1, 2 and 3MW). As a consequence of implementing these WFs, the emission of about 680,977 tons carbon dioxide ($tCO_2$) into the local atmosphere in Penghu Island annually could be avoided. Finally, based on the payback periods achieved, the order of implementation of the considered WFs can be identified more clearly. Longmen WF should be the first priority, and the next one should be SiyuWF and so on. Besides, this study provides much useful information for WF planning on Penghu Island.

• Journal of Animal Science and Technology
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• v.53 no.5
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• pp.475-480
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• 2011

This study was conducted to investigate the effects of different feeding level of TDN (Total Digestible Nutrients) on the generation of main greenhouse gases such as carbon dioxide and methane in Hanwoo cows. The diet TDN (kg) adjusted to achieve ADG of 0 g/day (Control), 200 g/day (T1), and 400 g/day (T2) of the maintenance level TMR (Total Mixed Ration) delivered twice a day at 08:30 and 17:30. Cow are housed in a respiration chamber and the environmental temperature was maintained at $20^{\circ}C$. The gases were measured for 24 hours using the multi-detector instrument Mamos-300. The analyzed methane emissions of T1 and T2 were 33.5% and 69.6% higher than control, respectively, and the carbon dioxide emissions were 21.1% and 40.6% higher than control. Also, the hourly pattern of carbon dioxide and methane production were showed very similar emission. Gas production showed peak after 1 hour of feeding and this gap was wider in the afternoon than in the morning hours. It is clearly conducted that $CO_2$ and $CH_4$ emissions were different by limited intake levels of feed.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.179-186
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• 2020

In this study, chitosan/zeolite composites were prepared by using basalt-based zeolite impregnated with aqueous chitosan solution for the adsorptive separation of CO₂. The prepared composites were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption analysis. In addition, the adsorption equilibrium isotherms for CO₂ and N₂ were measured at 298 K using a volumetric adsorption system, and the results were analyzed by applying adsorption isotherm equations (Langmuir, Freundlich, and Sips) and energy distribution function. It was found that CO₂ adsorption capacities were well correlated with the structural characteristics of chitosan and zeolite, and the ratio of elements [N/C, Al/(Si + Al)] formed on the surface of the composite. Moreover, the CO₂/N₂ adsorption selectivity was calculated under the mixture conditions of 15 V : 85 V, 50 V : 50 V, and 85 V : 15 V using the Langmuir equation and the ideal adsorption solution theory (IAST).

• Journal of Ginseng Research
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• v.3 no.2
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• pp.95-104
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• 1979

The effects of ginseng extracts on carbon dioxide generation, alcohol fermentation, and yeast cell production by Saccharomyces cerevisiae were investigated. The results are as follows. 1) In the process of fermentation, CO2 generation by yeast is faster in ginseng extracts media of 0.3%, 0. l% than in control. As the concentration of the extracts increases by 0.7% and 1.5%, CO2 generation is decreased. Among all these concentrations, CO2 generation is fastest in 0.3% of the extracts. 2) In the process of fermentation, the production of alcohol is larger in the order of 0.3%, 0.7% and 0.1% than in the control and least in 1.5%. 3) The number of yeast cell rapidly increased from 12 hours to 18 hours after cultivation and conspicuously increased in the order of 0.3%, 0.7%, 0.1%, control and 1.5%. 4) Dried yeast cell weight increased more in all the above concentration than control and among these it increased visibly in 0.3% of the extracts.

• Advances in materials Research
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• v.4 no.2
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• pp.63-76
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• 2015

The energy crisis involving depletion of fossil fuel resource is not the sole driving force for developing renewable energy technologies. Another driving force is the ever increasing concerns on the air quality of our planet, associated with the continuous and dramatic increase of the concentration of greenhouse gas (mainly carbon dioxide) emissions. The internal combustion engine is a major source of distributed $CO_2$ emissions caused by combustion of gasoline derived largely from fossil fuel. Another major source of $CO_2$ is the combustion of fossil fuels to produce electricity. New technologies for generating electricity from sources that do not emit $CO_2$, such as water, solar, wind, and nuclear, together with the advent of plug-in hybrid electric vehicles (PHEV) and even all-electric vehicles (EVs), offer the potential of alleviating our present problem. Therefore, the relevant technologies in $LiFePO_4$ as cathode material for Li-ion batteries suitable to the friendly environment are reviewed aim to provide the vital information about the growing field for energies to minimize the potential environmental risks.

• International Journal of Air-Conditioning and Refrigeration
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• v.15 no.1
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• pp.34-45
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• 2007

In order to reduce the compression power and to use the overall energy contained in LNG effectively, a combined cycle is devised and simulated. The combined cycle is composed of two cycles; one is an open cycle of liquid/solid carbon dioxide production cycle utilizing LNG cold energy in $CO_2$ condenser and the other is a closed cycle gas turbine which supplies power to the $CO_2$ cycle, utilizes LNG cold energy for lowering the compressor inlet temperature, and uses the heating value of LNG at the burner. The power consumed for the $CO_2$ cycle is investigated in terms of a solid $CO_2$ production ratio. The present study shows that much reduction in both $CO_2$ compression power (only 35% of the power used in conventional dry ice production cycle) and $CO_2$ condenser pressure could be achieved by utilizing LNG cold energy and that high cycle efficiency (55.3% at maximum power condition) in the gas turbine could be accomplished with the adoption of compressor inlet cooling and regenerator. Exergy analysis shows that irreversibility in the combined cycle increases linearly as a solid $CO_2$ production ratio increases and most of the irreversibility occurs in the condenser and the heat exchanger for compressor inlet cooling. Hence, incoming LNG cold energy to the above components should be used more effectively.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.22 no.3
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• pp.79-84
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• 2016

A kimchi container actively controlling $CO_2$ concentration by timely flushing of $CO_2$ gas was structured and tested in its capability and effectiveness because high $CO_2$ concentration enhances the sensory flavor of the product. The inlet and outlet valves of $CO_2$ gas were programmed to open and close allowing synchronous vent/$CO_2$ flush according to the requirements of its dissolution in the contained kimchi. During the chilled storage, the headspace of container could be maintained at desired high $CO_2$ concentration providing the preferred kimchi in sensory quality compared to control of the conventional container. However, there was no significant difference between the high $CO_2$ container and control (container simply closed with air) in kimchi quality attributes of pH, titratable acidity, total viable bacterial count, Lactobacillus sp. count and Leuconostoc sp. count. The flow rate and time interval of $CO_2$ flushing need to be adjusted considering the kimchi amount, headspace volume and ripening time. The designed system has potential to be applied in refrigerator appliances in homes and food service industry.

• Korea-Australia Rheology Journal
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• v.20 no.4
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• pp.235-243
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• 2008

The aim of this study is to explore the possibility of incorporating supercritical carbon dioxide ($scCO_2$) into twin screw extrusion process for the production of polypropylene-clay nanocomposite (PPCN). The $CO_2$ is used as a reversible plasticizer which is expected to rapidly transport polymeric chains into the galleries of clay layers in its supercritical condition inside the extruder barrel and to expand the gallery spacings in its sub-critical state upon emerging from die. The structure and properties of the resulting PPCNs are characterized using wide-angle X-ray diffraction (WAXD), transmission electron microscopy (TEM), rheometry, thermogravimetry and mechanical testing. In the processing of the PPCNs with $scCO_2$, optimum $scCO_2$ concentration and screw speed which maximized the degree of intercalation of clay layers were observed. The WAXD result reveals that the PP/PP-g-MA/clay system treated with $scCO_2$ has more exfoliated structure than that without $scCO_2$ treatment, which is supported by TEM result. $scCO_2$ processing enhanced the thermal stability of PPCN hybrids. From the measurement of linear viscoelastic property, a solid-like behavior at low frequency was observed for the PPCNs with high concentration of PP-g-MA. The use of $scCO_2$ generally increased Young's modulus and tensile strength of PPCN hybrids.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.652-657
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• 2007

This paper is an interim report on the investigation of thermodynamic properties of $CO_2$/oil mixture refrigerant. First, liquid density of POE (poly-ol ester) and PAG (poly alkylene glycol) were measured and expressed as a function of temperature. Then, a solubility equation was developed which enables us to calculate the weight fraction of $CO_2$ for the mixture in a liquid state. An experimental apparatus with a cell was constructed to measure P-$\upsilon$-T-$\chi$ data for $CO_2$/oil mixture. The volume of the cell was determined using a certain formula considering change in volume as a function of temperature and pressure. Then, experimental data were obtained over the temperatures $40^{\circ}C$, $50^{\circ}C$, $60^{\circ}C$, $70^{\circ}C$ and $80^{\circ}C$ with various mole fractions. Finally, assuming a primitive model of ideal gas, the volume of $CO_2$/oil mixture was predicted with a relatively larger error of 5.05% for $CO_2$/PAG and 8.81% for $CO_2$/POE. The volume of $CO_2$/oil mixtures would be better predicted using an appropriate equation of state, of which results will be reported soon.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.10
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• pp.15-27
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• 2022

Recently, as carbon dioxide (CO₂) emissions have increased overall and contributed to air pollution, and awareness of environmental degradation has grown. This study examines the impacts and causalities of economic globalization, economic growth, energy consumption, and capital formation on CO₂ emissions in China over the period 1971-2014. The vector error correction model (VECM) and Granger causality test on time-series data are employed to observe the interactions between CO₂ emission, economic globalization, and various economic factors, including economic growth, energy consumption, and capital formation, since China's early stage of globalization. The empirical results indicate the existence of bidirectional causalities from economic growth, gross capital formation, economic globalization, and CO₂ emission to energy consumption, and bidirectional casualty from energy consumption to CO₂ emission relationships in the short run. The findings of this study suggest that indirect bidirectional causalities from economic growth, economic globalization, and capital formation to CO₂ emission through energy consumption are observed. Moreover, economic globalization accelerates CO₂ emission in the short run but decreases it in the long run. To reduce CO₂ emissions, and to ensure sustainable economic growth and economic globalization progress, some crucial energy-saving and energy-efficiency policies, regulatory rules, and laws are recommended.