• Economic and Environmental Geology
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• v.47 no.2
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• pp.193-204
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• 2014

Shale gas has caused a change in the dynamics of gas market since development of horizontal drilling technic and hydraulic fracturing technic caused its commercial production. The commercial amount of shale gas is 187.5 trillions $m^3$ so human can use it for 59 years and the amount will increase in the future. Several nations such as USA, Canada, China and Russia have more and more interested in shale gas as a futuristic major energy source. In accordance with this trend in the world, the amount of studying theses for development of shale gas have increased so their theses became important increasingly. The number of searched theses (1986 ~ The first half of 2013) is 3,468 and has increased recently. Among 89 nations studying shale gas, USA has 637 theses as No.1 in the world. 1,813 global studying institutes have studied shale gas; in the analysis result of several studying institutes, US geological survey institute was ranked as No.1 for the quality level of shale gas study and intensity of global cooperation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.997-1002
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• 1999

The aim of the present study was to investigate effects of food preservative addition and changes in composition of herb extract product on the growth of spoilage yeast, Zygosaccharomyces sp. Herbs such as Panax ginseng, Cinnamomum cassia, Lycium chinense, Zyzyphus juiuba and Jingiber officinale were altogether put into water and essence was extracted at 80oC, and then the extract was concentrated at 75oC. The herb extract product was made by adding vitamins, amino acids and honey to the concentrated herb extract. The amount of gas produced from the herb extract product was increased as inoculated cell number increased but decreased as Brix concentration increased. Gases were produced in small amount when incubation was made at 4oC but large amounts of gases were produced at 25 or 40oC of incubation. The gas production and growth of Zygosaccharomyces sp. were measured after browning reaction was induced by heating at 85oC for 12 hours. It appeared that heating treatment did not induce any significant change in the gas production and growth of the cell. The effects of addition of various sugar to the herb extract produce were also invesigated. Amounts of gas production were in the order of glucose>sucrose>oligosaccharide>stevioside. The viable cell count was measured as 6.0$\times$107 CFU/g when glucose was added to the herb extract product. The viable cell counts were 5.0$\times$106, 3.0$\times$103, and 3.0$\times$102 CFU/g in sucrose, oligosaccharide and stevioside added herb extract product, respectively. The amount of gas production from the herb extract product was remarkably reduced by addition of such food preservatives as sodium benzoate and DF 100. TLC(thin layer chromatography) chromatogram of the herb extract showed stability of the herb extract in the above treatments.

• Journal of the Korean Institute of Gas
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• v.4 no.2 s.10
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• pp.33-36
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• 2000

As a result of electrostatic hazard analysis of electrostatic removing wear about combustible gas, in accordance with using period, character of charge voltage is shown that propensity is increased. but character of electrostatic charge amount is below standard(0.6 $\mu$C) of the hazard of electrostatic removing wear, It would seem that character of charge voltage is raised because of swelling phenomenon of the normal fiber and other phenomena. Besides, In some case '96 parka of electrostatic removing wear shown as 0.82$\mu$C that exceed the uppermost limit of the fire and explosion. Therefore, countermeasure or improvement and control are needed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.4
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• pp.259-264
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• 2011

Gas hydrate is formed by physical binding between water molecule and gas such as methane, ethane, propane, or carbon dioxide, etc., which is captured in the cavities of water molecule under the specific temperature and pressure. $1\;m^3$ hydrate of pure methane can be decomposed to the methane gas of $172\;m^3$ and water of $0.8\;m^3$ at standard condition. If this characteristic of hydrate is reversely utilized, natural gas is fixed into water in the form of hydrate solid. Therefore, the hydrate is considered to be a great way to transport and store of natural gas in large quantity. Especially the transportation cost is known to be 18~25% less than the liquefied transportation. However, when methane gas hydrate is artificially formed, its reaction time may be too long and the gas consumption in water becomes relatively low, because the reaction rate between water and gas is low. Therefore, for the practical purpose in the application, the present investigation focuses on the rapid production of hydrates and the increment of the amount of captured gas by adding zeolite into pure water. The results show that when the zeolite of 0.01 wt% was added to distilled water, the amount of captured gas during the formation of methane hydrate was about 4.5 times higher than that in distilled water, and the methane hydrate formation time decreased at the same subcooling temperature.

• Clean Technology
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• v.12 no.4
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• pp.217-223
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• 2006

The operating variables of a desorption step were experimentally investigated tor the cycle of the process made up of benzene adsorption, steam desorption, and drying step. The effect of adsorbent regeneration depending on existence and nonexistence of drying step was studied by breakthrough curves obtained in the adsorption step of the second cycle. The duration of drying step was determined by the experimental results. In case that the amount of nitrogen gas was fixed, the regeneration efficiency increased with the amount of steam. However, the effect of steam decreased as the amount of nitrogen increased. Therefore, it would be possible to predict the optimum amount of steam comparing the amount of nitrogen gas with amount of steam in economic view.

• Food Science and Preservation
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• v.15 no.6
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• pp.791-795
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• 2008

In order to establish the method to prepare and use the sulfur dioxide gas generating agent in low temperature storage of grape fruits, the $SO_2$ generation capacity from various sulfite compounds was investigated, and the method to regulate $SO_2$ gas generation and to detect the gas was developed. The conidial germination and mycelium growth of Botrytis cinerea which causes gray mold disease during grape fruit storage was completely inhibited at the $SO_2$ gas concentration of 400 ppm and 3200 ppm, respectively. Sodium hydrosulfite generated the most amount of $SO_2$ gas among the investigated 5 different sulfite or bisulfite compounds. By adjusting the number of pinholes on packaging film of the compound or by adding pH adjusting agent, e.g. citric acid or phosphates, it was possible to regulate the amount and duration of $SO_2$ gas generation from the compound. Because malachite green was quantitatively discolored by $SO_2$ gas, the solution or impregnated paper with the compound could be practically utilized as a indicator detecting $SO_2$ gas. Finally, when Muscat Bailey A grape was stored at low temperature with $SO_2$ gas generating agent, the disease incidence was reduced after storage.

• Asian Journal of Atmospheric Environment
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• v.2 no.2
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• pp.116-124
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• 2008

In this study, the Tier 2 method recommended by the Intergovernmental Panel on Climate Change (IPCC) was used to predict the methane generation rate at two landfill sites, designated as Y and C for purposes of this study, in South Korea. Factors such as the average annual waste disposal, methane emissions ($L_0$) and methane gas generation rate constant (k) were estimated by analyses of waste and the historical data for the landfills. The value of k was estimated by field experiments and then the changes in the methane generation rate were predicted through the year 2050, based on the value of k. The Y landfill site, which was in operation until the year 2008, will generate a total of 17, 198.7 tons by the end of 2018, according to our estimations. At the C landfill site, which will not be closed until the end of 2011, the amount of methane gas generated in 2011 will be 3,316 tons and the total amount of gas generated by 2029 will be 61,200 tons. The total production rate of methane gas at the C landfill is higher than that of the Y landfill. This indicates that the capacity of a landfill site affects the production rate of methane gas. However, the interrelation between the generation rate of methane and the value of k is weak. In addition, the generation of methane gas does not cease even when the operations at a landfill site come to a close and the methane gas production rate is at its highest at end of the operating life of a landfill site.

• Korean Journal of Environmental Agriculture
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• v.15 no.4
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• pp.472-478
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• 1996

It was conducted to compare the availabilities of parameters for evaluating the sink capacity of the broad leaves trees such as Acer saccharium, Ailanthus altissima, Ginkgo biloba, Platanus occidentalis and Salix pseudolasiogyne. These trees, repoted as resistant species to air pollutants, were exposed to $SO_2$, $NO_2$ and CO within a phytotron at $25^{\circ}C$ with 70% of relative humidity. Since the amount of ad- or absorbed gas does not always agree with the amount of accumlated pollutants in leaves and with the stomatal density, it is assumed that the amount of ad- or absorbed gas is the most basal index to evaluate the sink capacity of trees. The stomatal diffusive resistance, which has a good agreement with the amount of ad- or absorbed gas, is also available for evaluating the sink capacity of broad leaves trees.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.3
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• pp.301-308
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• 2006

The present work explores the effect of carbon-supported platinum catalyst on the HI decomposition using gas adsorption analyzer, thermogravimetry, X-ray diffractometry, scanning electron microscopy, and gas chromatography. For this purpose, three types of activated carbon (C), Pt/C-1 wt.%, and Pt/C-5 wt.% were prepared. The HI gas conversion is crucially influenced by the amount of Pt on the carbon support. The more the amount of Pt was, the higher results in the HI gas conversion. For three types of catalysts, HI conversion increased with increasing the decomposition temperature but with decreasing the space velocity. The increase of HI conversion with temperature was more pronounced in activated carbon than that in Pt/C. From EDX result, it was found that the activated carbon comprised higher amount of iodine than the Pt/C after the decomposition reaction. This implies that the HI conversion is closely related to the amount of Iodine.

• Journal of Climate Change Research
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• v.9 no.1
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• pp.75-80
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• 2018

The problem of water shortages and water related disasters caused by climate change has increased the seriousness of water problems and the importance of water treatment technology capable of securing clean water is expanding. In this study, we analyzed not only the water pollutant generated by the filtration system technology of various water treatment technologies but also the indirect greenhouse gas emissions generation, and analyzed the influence on the environment. The subjects of study are Fabric Filter, Reverse Osmosis System and Pressurized Microfiltration Device which are widely used for water treatment and we analyzed the impact on the environment using the Life Cycle Assessment (LCA) method using the electricity amount necessary for use, the water purification efficiency, the throughput per ton and the cost. The amount of greenhouse gas generated when the Pressurized Microfiltration Device operates for 1 year is $2.15E+04kg\;CO_2-eq$., Fabric Filter is $3.29E+04kg\;CO_2-eq$., and Reverse Osmosis System is $1.68E+05kg\;CO_2-eq$. As a result of analyzing the amount of greenhouse gas generated at the time of purifying 1 ton of the Pressurized Microfiltration Device and the conventional filtration system, the Pressurized Microfiltration Device was $20.5g\;CO_2-eq$., Fabric Filter was $34.7g\;CO_2-eq$., and Reverse Osmosis System was $191.7g\;CO_2-eq$. The amount of greenhouse gas generated was calculated to be 41.0% less than that of the Fabric Filter by the Pressurized Microfiltration Device and 89.3% less than the Reverse Osmosis System. From the viewpoint of climate change, it is necessary to select a filtration system that takes climate change into account, not from the viewpoint of water quality removal efficiency and economic efficiency according to future water treatment applications, and it is necessary to select a water treatment filtration system more researches and improvements will be made for.