• Land and Housing Review
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• v.11 no.3
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• pp.61-68
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• 2020

Advanced glazing systems with excellent heat transmission values (Ug-Value) have been developed to reduce the energy consumption and the greenhouse gas emission. This study proposes a triple glazing system consisting of gaps with a vacuum and a carbon dioxide gas layer which is one of greenhouse gases. As a fundamental stage, this study is focused on calculating the optimal glazing thickness and the Ug-Value via a computer simulation, Therm & Window package. As the results, it was presented that the optimal thickness of the proposed triple glazing system is 22.2 mm, and the Ug-Value is 0.273 W/㎡·K. If this glazing system is to be applied to buildings, it could not only reduce building energy consumption but could also contribute to the treatment of carbon dioxide gas which is one of greenhouse gases.

• Bulletin of the Korean Chemical Society
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• v.21 no.11
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• pp.1077-1084
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• 2000

The dipolar effect of neighboring protons that are not directly bonded to the carbon of interest on coupled carbon-13 relaxation in a simple organic molecule has been studied by comparing the relaxation behaviors of labeled carbon-13 in $Br13CH_2COOH$ with those in $BrCH_213COOH.$ Various pulse sequences, such as coupled inversion recovery pulse sequence, J-negative and J-positive pulse sequence, and nonselective and selective proton ${\pi}pulse$ sequence, were employed to perform the required coupled spin relaxation experiments. To gain information on various spectral densities, including that of dipolar-CSA cross correlation, the experiments were performed on two different spectrometers, operating, respectively, at 50.31 and 125.51MHz for 13C. The magnitude of CH dipolar spectral densities for $BrCH_213COOH$ was found to be about 8% of those for $Br13CH_2COOH$, which means the effect due to the protons not directly bonded to the carbon of interest is small but not completely negligible.

• Journal of Environmental Science International
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• v.23 no.11
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• pp.1827-1833
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• 2014

This study has been carried out to present the valuation system of soil carbon sequestration potentials of soil in accordance with the new climate change scenarios(RCP). For that, by analyzing variation of soil carbon of the each type of agricultural land use, it aims to develop technology to increase the amount of carbon emissions and sequestration. Among the factors which affects the estimation of determining the soil carbon model and influence power after the measurement on soil organic carbon, under the center of a causal relationship between the explanatory variables this study were investigated. Chemical fertilizers (NPK) decreased with increasing the amount of soil organic carbon and as with the first experimental results, when cultivating rice than pepper, the fact that soil organic carbon content increased has been found out. The higher the carbon dioxide concentration, the higher the amount of organic carbon in the soil and this result is reliable under a 10% significance level. On the other hand, soil organic carbon, humus carbon and hot water extractable carbon has been found out that was not affected the soils depth, sames as the result of the first year. The higher concentration of carbon dioxide, the higher carbon content of humus and hot water extractable carbon content. According to IPCC 2006 Guidelines and the new climate change scenario RCP 4.5 and the measurement results of the total amount of soil organic carbon to the crops due to abnormal climate weather, 1% increase in atmospheric carbon dioxide concentration was found to be small when compared to the growing rate of increasing 0.01058% of organic carbon in the soil.

• Journal of radiological science and technology
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• v.38 no.2
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• pp.81-87
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• 2015

This study was designed the band material in order to reduce the exposure pressure of the breast and the material was measured of Radiolucent and radiation properties with a radiation materials of PC, PMMA, Carbon. Also the image quality by image analysis to obtain the following results are below: Unfors Xi dosimetry using radiation transmittance when the results of 8.353mGy is measured after removal of the cuff, the PC 6.308mGy, PMMA 6.223mGy, Carbon 7.218mGy were measured respectively. Semi-layer PC 0.375mmAl, PMMA 0.370mmAl, with Carbon 0.360mmAl Carbon, PC, PMMA was higher radiation properties and transparency in order. InLight / OSL NanoDotTM dosimeter was used in the cuff and then removed by placing the dosimeter measured results center on 1.143mGy, at the edge 12.56mGy, on the central PC 8.990mGy, at the edge 10.291mGy, PMMA center on 8.391mGy, the edge 9.654mGy, on Carbon center 9.581mGy, 11.313 mGy were measured at the edge of Carbon, PC, PMMA showed a high permeability in order. Image Pixel average J is then removed from the cuff 976.655, PC 831.032, PMMA 819.069, Carbon 897.118 Carbon, PC, PMMA was measured by high order.

• Journal of Mechanical Science and Technology
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• v.14 no.11
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• pp.1276-1285
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• 2000

The solubility, the surface concentration and the dissolution behavior of carbon dioxide in deep sea were numerically investigated. Base on the calculations the relations between the surface concentration of liquid carbon dioxide droplet with the hydrate film and the solubility and those between the ambient carbon dioxide concentration in the plume and the dissolution rate were obtained. The result show that a carbon dioxide droplet is released both at 1000 m in depth with the initial droplet diameter of 0.011 m or less and at 1500 m in depth with a diameter of 0.015 m or less, and the droplet is completely dissolved below 500 m in depth. The hydrate film acts as a resistant layer for the dissolution of liquid carbon dioxide, and the effect of the hydrate film on the dissolution of liquid carbon dioxide depended upon the depth.

• Journal of the Korean Ceramic Society
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• v.45 no.11
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• pp.662-666
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• 2008

Electrochemical properties of carbon cryogel electrode for the application of composite electrode materials mixed with metal oxide in supercapacitor have been studied. Carbon cryogels were synthesized by sol-gel polycondensation of resorcinol with form aldehyde, followed by a freeze drying, and then pyrolysis in an inert atmosphere. Physical properties of carbon cryogel were characterized by BET, X-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that carbon cryogel is amorphous material. The electrochemical properties of carbon cryogel were measured by cyclic voltammetry as a function of concentration of liquid electrolyte, galvanostatic charge-discharge with different scan rates and electrochemical impedance measurements. The result of cyclic voltammetry indicated that the specific capacitance value of a carbon cryogel electrode was approximately 150.2 F/g (at 5 mV/s in 6M KOH electrolyte).

• Journal of Korean Society on Water Environment
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• v.39 no.6
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• pp.433-438
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• 2023

This study investigated the growth and metabolic characteristics of Arthrospira platensis (A. platensis) according to pH, which has an alkaline optimal pH. The intake of inorganic carbon was expected to be the highest at the optimum pH 9, but it was different from the expectation, so the cause of the excessive intake of inorganic carbon at pH 7 was investigated. We tried to verify the triacylglycerol (TAG) synthesis metabolic mechanism because it was assumedthat the inorganic carbon intake of A. platensis according to pH is closely related to lipid production inside the cell. To verify this, the effects of pH on inorganic carbon intake were examined through lipid analysis inthe cell of A. platensis according to pH. As a result, in the case of the effect of inorganic carbon intake of A. platensis according to pH on TAG content, pH 9 and pH 11 showed no significant difference in TAG content, but at pH 7, it was two times higher compared to pH 9 and pH 11. It was assumed that the reason why A. platensis excessively consumed inorganic carbon at pH 7 was because itincreased the TAG content in proportion to the intake of inorganic carbon to protect cells from external pH stress. In addition, it is considered that the TAG content produced in proportion to the intake of inorganic carbon is because acetyl-CoA produced in the Calvin cycle is required for the synthesis of TAG.

• Carbon letters
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• v.9 no.4
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• pp.298-302
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• 2008

Carbon blacks could be used as the filler for the electromagnetic interference (EMI) shielding. The poly vinyl alcohol (PVA) and polyvinylidene fluoride (PVDF) were used as the matrix for the carbon black fillers. Porous carbon blacks were prepared by $CO_2$ activation. The activation was performed by treating the carbon blacks in $CO_2$ to different degrees of burnoff. During the activation, the enlargement of pore diameters, and development of microporous and mesoporous structures were introduced in the carbon blacks, resulting in an increase of extremely large specific surface areas. The porosity of carbon blacks was an increasing function of the degree of burn-off. The surface area increased from $80\;m^2/g$ to $1142\;m^2/g$ and the total pore volume increased from $0.14073\;cc{\cdot}g^{-1}$ to $0.9343\;cc{\cdot}g^{-1}$. Also, the C=O functional group characterized by aldehydes, ketones, carboxylic acids and esters was enhanced during the activation process. The EMI shielding effectiveness (SE) of raw N330 carbon blacks filled with PVA was about 1 dB and those of the activated carbon blacks increased to the values between 6 and 9 dB. The EMI SE of raw N330 carbon blacks filled with PVDF was about 7 dB and the EMI SE increased to the range from 11 to 15 dB by the activation.

• Carbon letters
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• v.8 no.1
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• pp.6-11
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• 2007

Carbon/$TiO_2$ composites were prepared by $CCl_4$ solvent mixing method with different mixing ratios. Since the carbon layers derived from pitch on the $TiO_2$ particles were porous, the Carbon/$TiO_2$ composite series showed a good adsorptivity and photo decomposition activity. The BET surface area for the carbon layer in the sample increases to increasing with pitch contents. The SEM results present to the characterization of porous texture on the Carbon/$TiO_2$ composite and pitch distributions on the surfaces for all the materials used. From XRD data, a weak and broad carbon peak of graphene with pristine anatase peaks were observed in the X-ray diffraction patterns for the Carbon/$TiO_2$. The EDX spectra show the presence of C, O and S with strong Ti peaks. Most of these samples are richer in carbon and major Ti metal than any other elements. Finally, the excellent photocatalytic activity of Carbon/$TiO_2$ with slope relationship between relative concentration (C/$C_0$) of MB and t could be attributed to the homogeneous coated pitch on the external surface by $CCl_4$ solvent method.

• Environmental Engineering Research
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• v.22 no.1
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• pp.40-54
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• 2017

According to FAO, "agricultural sectors are particularly exposed to the effects of climate change and increases climate variability". As a result, the study makes an attempt to answer the question: Is there a causal effect between agricultural production and carbon dioxide emissions in Ghana? By employing a time series data spanning from 1960 to 2015 using the Autoregressive Distributed Lag method. There was evidence of a long-run equilibrium relationship running from copra production, corn production, green coffee production, milled rice production, millet production, palm kernel production and sorghum production to carbon dioxide emissions. The short-run equilibrium relationship shows that, a 1% increase in copra and green coffee production will increase carbon dioxide emissions by 0.22% and 0.03%, a 1% increase in millet and sorghum production will decrease carbon dioxide emissions by 0.13% and 0.11% in the short-run while a 31% of future fluctuations in carbon dioxide emissions are due to shocks in corn production. There was bidirectional causality between milled rice production and carbon dioxide emissions, millet production and carbon dioxide emissions and, sorghum production and carbon dioxide emissions; and a unidirectional causality running from corn production to carbon dioxide emissions and carbon dioxide emissions to palm kernel production.