• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.967-972
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• 2017

Objective: Two experiments were conducted to determine the effects of forage-to-concentrate (F:C) ratio on the nutrient digestibility and enteric methane ($CH_4$) emission in growing goats and Sika deer. Methods: Three male growing goats (body weight $[BW]=19.0{\pm}0.7kg$) and three male growing deer ($BW=19.3{\pm}1.2kg$) were respectively allotted to a $3{\times}3$ Latin square design with an adaptation period of 7 d and a data collection period of 3 d. Respiration-metabolism chambers were used for measuring the enteric $CH_4$ emission. Treatments of low (25:75), moderate (50:50), and high (73:27) F:C ratios were given to both goats and Sika deer. Results: Dry matter (DM) and organic matter (OM) digestibility decreased linearly with increasing F:C ratio in both goats and Sika deer. In both goats and Sika deer, the $CH_4$ emissions expressed as g/d, g/kg $BW^{0.75}$, % of gross energy intake, g/kg DM intake (DMI), and g/kg OM intake (OMI) decreased linearly as the F:C ratio increased, however, the $CH_4$ emissions expressed as g/kg digested DMI and OMI were not affected by the F:C ratio. Eight equations were derived for predicting the enteric $CH_4$ emission from goats and Sika deer. For goat, equation 1 was found to be of the highest accuracy: $CH_4(g/d)=3.36+4.71{\times}DMI(kg/d)-0.0036{\times}neutral$ detergent fiber concentrate (NDFC,g/kg)+$0.01563{\times}dry$ matter digestibility (DMD,g/kg)-$0.0108{\times}neutral$ detergent fiber digestibility (NDFD, g/kg). For Sika deer, equation 5 was found to be of the highest accuracy: $CH_4(g/d)=66.3+27.7{\times}DMI(kg/d)-5.91{\times}NDFC(g/kg)-7.11{\times}DMD(g/kg)+0.0809{\times}NDFD(g/kg)$. Conclusion: Digested nutrient intake could be considered when determining the $CH_4$ generation factor in goats and Sika deer. Finally, the enteric $CH_4$ prediction model for goats and Sika deer were estimated.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.923-938
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• 2015

This study was conducted to serve as the basis for establishing a standard cultivation, which enhances the alternative utilization of pig manure, a major cause of environmental pollution, by finding a means for reducing greenhouse gas emissions for eco-friendly cultivation. In a laboratory, $CH_4$ and $CO_2$ emission patterns were investigated corresponding to incremental pig manure treatments in paddy soil. The emissions peaked 12 to 27 days after manure application in the 100~400% applications. It was found that increasing applications of pig manure resulted an increase in $CH_4$ and $CO_2$ emissions. Additionally, application of more than 150% emitted a larger amount of these gasses than applying chemical fertilizer. However, the test application of 100% pig manure emitted a smaller amount of $CH_4$ and hence Global Warming Potential (GWP) than those emitted by chemical fertilizer. If appropriate amount of fertilization is applied in compliance with the standard application rate, the pig manure may be effective in reducing greenhouse gas emissions and the soil environment made more favorable than with the use of chemical fertilizer.

• Journal of Environmental Science International
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• v.22 no.7
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• pp.837-845
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• 2013

This study was designed to synthesize mesoporous carbon, porous carbonic material and to characterize its surface in an attempt to adsorption methane gas($CH_4$). Synthesis of mesoporous carbon was carried out under two steps ; 1. forming a RF-silica complex with a mold using CTMABr, a surfactant, and TEOS, raw material of silica, and 2. eliminating silica through carbonization and HF treatment. The mesoporous carbon was synthesized under various conditions of synthesis time and calcination. Eight different types of mesoporous carbon, which were designated as MC1, MC2, MC3, MC4, MCT1, MCT2, MCT3, and MCT4, were prepared depending upon preparation conditions. The analysis of mesoporous carbon characteristics showed that the calcination of silica stabilized the mixed structure of silica and carbonic complex, and made the particle uniform. The results also showed that hydrothermal synthesis time did not have a strong influence on the size of pore. The bigger specific surface area was obtained as the hydrothermal synthesis time was extended. However, the specific surface area was getting smaller again after a certain period of time. In adsorption experiments, $CH_4$ was used as adsorbate. For the case of $CH_4$, MCT3 showed the highest adsorption efficiency.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.776-783
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• 2010

Co and Ni catalysts supported on $Al_2O_3$ for partial oxidation of methane producing hydrogen were synthesized using impregnation to incipient wetness. The activities of these catalysts for the partial oxidation of methane was investigated at 1 atm and $CH_4/O_2=2.0$ in the temperature range of $450{\sim}650^{\circ}C$. The reaction activity of $Ni/Al_2O_3$ and $Co/Al_2O_3$ catalysts with different loading was investigated. And the beneficial effects of Ni addition to $Co/Al_2O_3$ and the promotional effects of Ce and La addition to $Ni/Al_2O_3$ and $Co/Al_2O_3$ were investigated. These catalysts were characterized by XRD and SEM/EDX. Comparing catalyst loadings, 10 wt% Co and 10 wt% Ni were found to be optimal at the experimental conditions. The 10 wt% $Ni/Al_2O_3$ and 10 wt% $Co/Al_2O_3$ catalysts in partial oxidation of methane showed $CH_4$ conversions and CO selectivity close to the thermodynamic equilibrium levels, but showed lower $H_2$ selectivity than equilibrium level. The addition of Ni to $Co/Al_2O_3$ exhibited higher $H_2$ selectivity but beneficial effect was not observed in the $CH_4$ conversion. Addition of Ce to $Co/Al_2O_3$ and addition of La to $Ni/Al_2O_3$ a improved the $CH_4$ conversion level and $H_2$ selectivity.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.4
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• pp.256-262
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• 2003

The emission of methane and nitrous oxide was measured from fields of upland rice and soybean. Rice cultivar, Daejinbyeo, was seeded in a row of 30 cm space in upland soil on April 28, 2001. The fields were irrigated with sprinkler irrigation or natural precipitation. Three soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong, were sown with seeding space of $60{\times}15cm$ on June 16, 2001. Gas samples were collected twice a week during the growth period, and methane and nitrous oxide were analyzed. Methane emission from upland rice field of sprinkler irrigation was $3.5kg\;CH_4\;ha^{-1}$. However, negative emission of methane, $-1.7kg\;CH_4\;ha^{-1}$, was observed in upland rice field of natural precipitation. Total nitrous oxide emission from upland rice field of sprinkler irrigation was $50.8kg\;N_2O\;ha^{-1}$, while the emission in the field of natural precipitation was $8.3kg\;N_2O\;ha^{-1}$. Global warming potentials (GWP) in the upland rice fields of sprinkler irrigation and natural precipitation were 15,822 and $2,216kg\;CO_2\;ha^{-1}$, respectively. Methane emissions from fields of soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong were -14.7, -4.3 and $4.8kg\;CH_4\;ha^{-1}$, respectively. Total nitrous oxide emissions from fields of soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong were 4.7, 4.6 and $3.0kg\;N_2O\;ha^{-1}$, respectively. Total GWPs for soybean cultivars Jangyeobkong, Taekwangkong and Hwangkeumkong were 1152, 1323 and $1027kg\;CO_2\;ha^{-1}$, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.557-562
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• 2007

The purpose of this paper is to investigate the reforming characteristics and maximum operating condition for the hydrogen production by methane reforming using the compression ignition engine induced partial oxidation. An dedicated compression engine used for methane reforming was decided operating range. The partial oxidation reforming was investigated with oxygen enrichment which can improve hydrogen production, compared to general reforming. Parametric screening studies were achieved as $O_2/CH_4$ ratio, total flow rate, and intake temperature. When the variations of $O_2/CH_4$ ratio, total flow rate, and intake temperature were 1.24, 208.4 L/min, and $400^{\circ}C$, respectively, the maximum operating conditions were produced hydrogen and carbon monoxide. Under the condition mentioned above, synthetic gas were $H_2\;22.77{\sim}29.22%,\;CO\;21.11{\sim}23.59%$.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1238-1243
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• 2018

Objective: Two experiments were conducted to determine the effects of feeding level on nutrient digestibility and enteric methane ($CH_4$) emissions in growing goats and Sika deer. Methods: Three growing male goats (initial body weight [BW] of $22.4{\pm}0.9kg$) and three growing male deer (initial BW of $20.2{\pm}4.8kg$) were each allotted to a respiration-metabolism chamber for an adaptation period of 7 d and a data collection period of 3 d. An experimental diet was offered to each animal at one of three feeding levels (1.5%, 2.0%, and 2.5% of BW) in a $3{\times}3$ Latin square design. The chambers were used for measuring enteric $CH_4$ emission. Results: Nutrient digestibility decreased linearly in goats as feeding level increased, whereas Sika deer digestibility was not affected by feeding level. The enteric production of $CH_4$ expressed as g/kg dry matter intake (DMI), g/kg organic matter intake, and % of gross energy intake decreased linearly with increased feeding level in goats; however, that of Sika deer was not affected by feeding level. Six equations were estimated for predicting the enteric $CH_4$ emission from goats and Sika deer. For goat, equation 1 was found to be of the highest accuracy: $CH_4(g/d)=6.2({\pm}14.1)+10.2({\pm}7.01){\times}DMI(kg/d)+0.0048({\pm}0.0275){\times}dry$ matter digestibility (DMD, g/kg)-0.0070 (${\pm}0.0187$)${\times}$neutral detergent fiber digestibility (NDFD; g/kg). For Sika deer, equation 4 was found to be of the highest accuracy: $CH_4(g/d)=-13.0({\pm}30.8)+29.4({\pm}3.93){\times}DMI(kg/d)+0.046(0.094){\times}DMD(g/kg)-0.0363({\pm}0.0636){\times}NDFD(g/kg)$. Conclusion: Increasing the feeding level increased $CH_4$ production in both goats and Sika deer, and predictive models of enteric $CH_4$ production by goats and Sika deer were estimated.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.1
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• pp.23-28
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• 2015

This study was conducted to evaluate the biodegradation characteristics of food waste on various collection systems using anaerobic batch test. The ultimate methane production from food waste in standard plastic garbage bags (sample A) was $285.6mL\;CH_4/g$ volatile solids (VS) which is the lowest, and reaction constant was $0.215d^{-1}$. The ultimate methane production from food waste in waste vessel based on RFID (sample D) was $493.4mL\;CH_4/g$ VS which is the highest, and reaction constant was $0.162d^{-1}$. The determinants of rate limiting step on all samples showed positive numbers, and the methane production step was found a rate limiting step.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1601-1607
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• 2016

This study was conducted to determine the effect of lysozyme addition on in vitro rumen fermentation and to identify the lysozyme inclusion rate for abating methane ($CH_4$) production. An in vitro ruminal fermentation technique was done using a commercial concentrate to rice straw ratio of 8:2 as substrate. The following treatments were applied wherein lysozyme was added into 1 mg dry matter substrate at different levels of inclusion: Without lysozyme, 2,000, 4,000, and 8,000 U lysozyme. Results revealed that, lysozyme addition had a significant effect on pH after 24 h of incubation, with the highest pH (p<0.01) observed in 8,000 U lysozyme, followed by the 4,000 U, 2,000 U, and without lysozyme. The highest amounts of acetic acid, propionic acid (p<0.01) and total volatile fatty acid (TVFA) (p<0.05) were found in 8,000 U after 24 h of incubation. The $CH_4$ concentration was the lowest in the 8,000 U and the highest in the without lysozyme addition after 24 h of incubation. There was no significant differences in general bacteria, methanogen, or protozoan DNA copy number. So far, addition of lysozyme increased the acetate, propionate, TVFA, and decreased $CH_4$ concentration. These results suggest that lysozyme supplementation may improve in vitro rumen fermentation and reduce $CH_4$ emission.

• Korean Journal of Agricultural Science
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• v.51 no.2
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• pp.227-238
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• 2024

Methane (CH₄) is an important greenhouse gas, with a short-term greenhouse effect 80-fold that of carbon dioxide. Blast furnace slag used as a base ingredient for silicate fertilizer, and contained Fe³⁺, which acts as reduction of CH₄ emissions in flooded rice paddy. This study was evaluated the effects of the silicate fertilizer with different rates of the iron slag on CH₄ emissions and rice growth. In this study, the SF 0.0% was applied with silicate fertilizer containing 0.0% of the iron slag, while the SF 2.5% and SF 5.0% were treated with silicate fertilizer containing 2.5 and 5.0%, respectively. The CH₄ emissions during rice cropping period were assessed using a closed-chamber method and then determined by Gas chromatography. The CH₄ fluxes were reduced by 17% (SF 0.0%), 17% (SF 2.5%), and 8% (SF 5.0%) compared to the treatment with only-inorganic fertilization (control). Conversely, rice grain yield increased by 15 - 30% compared to the control owing to the improvement of soil quality by silicate fertilization. In particular, soil pH, available phosphorus and available silicic acid content were increased with the increase in the iron slag rates from 0.0 to 5.0%. These contributed to a significant increase in rice growth such as 1,000-grains weight and percentage of filled grains. Consequently, these findings were indicated that the application of silicate fertilizer containing 2.5 - 5.0% of iron slag would be the most effective in both CH₄ reduction and rice growth.