• Food Science and Preservation
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• v.19 no.1
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• pp.19-25
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• 2012

An experiment was conducted to find out the effect of brushing treatment during cultivation on the postharvest quality of the baby leaf vegetable, specifically tah tasai Chinese cabbage (Brassica campestris var. narinosa). The effect of mechanical brushing during cultivation on the postharvest quality was determined in terms of the quality changes in weight loss, gas partial pressure, leaf color, and appearance during storage using a 30-${\mu}m$-thick polypropylene film at $16^{\circ}C$. The brushing treatment included brushing with A4 paper back and forth 50 times a day. The study revealed that the growths on the brushing-treated plant group were less than those on the control group. The structure of the leaf tissue of the brushing-treated plant also tended to be less compact than that of the non-treated plant. The brushing treatment resulted in less growth and denser plant tissues as well as in differences in the gas $O_2$ consumption and $CO_2$ accumulation after packaging. For the gas partial pressure, the $O_2$ consumption and $CO_2$ accumulation of the brushing-treated plant tended to be less than those of the non-treated plant. There were no differences, however, between the brushing-treated plant and control groups in the SPAD value and appearance. The study results also suggested that after packaging, the effects of the brushing treatment during cultivation on the quality of the tah tasai Chinese cabbage baby leaf vegetable was not significant. As such, it is recommended that effective post-harvest methods of improving the product quality of the baby leaf vegetable be further investigated.

• Membrane Journal
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• v.20 no.2
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• pp.127-134
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• 2010

This study is conducted about the system that reduces organism after fermenting food waste from a food waste disposal equipment, divides gas made when food waste is fermented into gas and water, and then sends gas to a reactor again, condenses water, and apply it to the MBR system with submerged MF hollow fiber membranes. A submerged MF hollow fiber membrane module was installed to a food waste disposal equipment and a water treatment system made by Bio Hitech Co,. Ltd. to process food waste generated from a staff cafeteria in a H institute for 90 days. For initial seeding of a food waste disposal equipment, 305 kg of rice bran, chaff, and sawdust as well as 1,648 kg of food were input during the operation, and 1,600 L of condensed wastewater occurred. Fermented by-product after finishing running a food waste disposal equipment was 386 kg and its reduction was shown to be 80%. The organism was processed by applying submerged MF hollow fiber membrane module to the MBR system of condensed wastewater, and the result shows reduction rates were BOD 99.9%, COD 97.5%, SS 98.6%, T-N 54.6% and T-P 34.7% and the total colon bacillus was perfectly eliminated.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.347-354
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• 2014

Economic evaluation of the manufacturing technology of high-value chemicals through the carbonation reaction of carbon dioxide contained in the flue gas was performed, and analysis of the IRR (Internal Rate of Return) and whole profit along the production plan of the final product was conducted. Through a carbonation reaction with sodium hydroxide that is generated from electrolysis and by using carbon dioxide in the combustion gas that is generated in the power plant, it is possible to get a high value products such as sodium bicarbonate compound and also to reduce the carbon dioxide emission simultaneously. The IRR (Internal Rate of Return) and NPV (Net Present Value) methods were used for the economic evaluation of the process which could handle carbon dioxide of 100 tons per day in the period of the 20 years of plant operation. The results of economic evaluation showed that the IRR of baseline case of technology was 67.2% and the profit that obtained during the whole operation period (20 years) was 346,922 million won based on NPV value. When considering ETS due to the emissions trading enforcement that will be activated in 2015, the NPV was improved to a 6,000 million won. Based on this results, it could be concluded that this $CO_2$ carbonation technology is an cost-effective technology option for the reduction of greenhouse gas.

• Journal of Environmental Health Sciences
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• v.21 no.4
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• pp.1-9
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• 1995

This study was carried to investigate the biodegradability of phenol in the wastewater with the two sludge blanket-packed bed reactor in series. Each reactor had a dimension of 0.09 m i.d. and 1.5 m height and consisted of two regions. The lower region was a sludge blanket of 0.5 m height and the upper region was a packed-bed of 1 m height. The packed bed region was charged with ceramic raschig rings of 10 mm i.d., 15 mm o.d. and 20 mm length. The reactors were operated at 35$\circ$C and the hydraulic retention time(HRT) was maintained 24 hours. The synthetic wastewater composed of glucose and phenol as major components was fed into the reactor in a continuous mode with incereasing phenol concentration. In addition, the nutrient trace metals($Na^+, Mg^{2+}, Ca^{2+}, PO_4^{3-}, NH_4^+, Co^{2+}, Fe^{2+}$ etc.) were added for growing anaerobes. The phenol concentration of the effluent, the overall gas production, the composition of product gas, the efficiency of COD reduction and the duration of acclimation period were measured to determine the performance of the anaerobic wastewater treatment system as the phenol concentration of the influent was increased from 600 to 2400 mg//l. Successfully stable biodegradation of phenol could be achieved with the anaerobic treatment system from 600 to 1, 800 mg/l of the influent phenol concentration. The upper level of influent phenol loading was high enough to meet most of the practical requirement. The duration of acclimation increased with the phenol loading. At steady state of the influent phenol concentration of 1800 mg/l, the treatment performance indicated the phenol reduction efficiency of 99%, the COD reduction efficiency of 99% and the gas production rate of 37 l/day. At the influent phenol concentration of 2400 mg/l, however, the operation of the treatment system was noted unstable. While the concentration of methane in biogas decreased with increasing the influent phenol loading, the carbon dioxide was increased. However, the concentration of hydrogen was varied negligibly. The concentration of methane was high enough to be used as a fuel. As a result, it is suggested that anaerobic phenol wastewater treament was economical in the sense of energy recovery and wastewater treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1143-1150
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• 2003

This study was conducted to investigate in vitro methane production of feed ingredients and relationship between the content of crude nutrients and methane production. Feed ingredients (total 26) were grouped as grains (5 ingredients), brans and hulls (8), oil seed meals (9) roughages (3), and animal by-product (1) from their nutrient composition and their methane production protential were measured by in vitro gas test. Among the groups, the in vitro methane productions for both 6 and 24 h incubation were highest in grains, followed by brans and hulls, oil meals and roughages, animal byproducts. Within the group of grains, methane production from wheat flour was the highest, followed by wheat, corn, tapioca, and then oat. Within the brans and hulls, soybean hull showed the highest methane production and cotton seed hull, the lowest. Methane production from oil meals was lower compared with grains and brans and hulls, and in decreasing order production from canola meal was followed by soybean meal, coconut meal, and corn germ meal (p<0.01). Three ingredients were selected and the interactions among feed ingredients were evaluated for methane production. Correlation coefficient between measured and estimated values of the combinations were 0.91. Methane production from each feed ingredient was decreased with increasing amount of crude fiber (CF), protein (CP) and ether extract (EE), whereas positive relationship was noted with the concentrations of N-free extract (NFE). The multiple regression equation (n=134) for methane production and nutrient concentrations was as follows. Methane production (ml/0.2 g DM)=(0.032${\times}$CP)-(0.057${\times}$EE)-(0.012${\times}$CF)+(0.124${\times}$NFE) (p<0.01; $R^2$=0.929). Positive relationship was noted for CP and NFE and negative relationship for CF and EE. It seems possible to predict methane production potential from nutritional composition of the ingredients for their effective application on formulating less methane emitting rations.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.20 no.2
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• pp.29-33
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• 2014

Active air flushing mini-pumps were installed in a rigid polypropylene container ($32cm{\time}23cm{\time}18cm$) containing 900 g of fresh green peppers for effectively controlling its $O_2$ concentration on real time basis to preserve the product quality. The performance of the constructed system was compared to that of the modified atmosphere (MA) container system with gas diffusion tube controlled in close/open cycles responding to real time $O_2$ concentration at 10 and $20^{\circ}C$. In the control logic, the $O_2$ concentration was programmed to be located exactly at 13% or stay in the range of 13-15%. The active air flushing system could control the $O_2$ concentration in the desired level or range at both temperatures, while the passive diffusion system could work only under the low temperature condition of $10^{\circ}C$. At higher temperature of $20^{\circ}C$, the passive diffusion system could not manage the produce respiration increased more highly than the gas transfer through the diffusion tube, resulting in too low $O_2$ concentration and too high $CO_2$ concentration which would be injurious to the green pepper. When tested at $20^{\circ}C$, the MA container system could preserve the green pepper better than the perforated air package in terms of weight loss, ascorbic acid and chlorophyll contents and firmness.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.981-988
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• 2004

An Experiment was conducted to investigate the effects of Natufermen$^{(R)}$;(Aspergillus oryzae) supplementation on the performance, ammonia gas production, microbial population in manure and serum IgG in pigs. Forty eight cross bred(YLD) weanling pigs(35d old) were assigned to 4 treatments; Control(C), $C^+$ Natufermen 0.1%, $C^+$ Natufermen 0.2% $C^+$natufermen 0.3% for 6 week feeding trial. Each treatment had 4 replications of 3 pigs each. Natufermen$^{(R)}$ supplemented treatments tended to increase ADG and ADFI, but there were no significant differences among treatments. Supplementation of Natufermen$^{(R)}$ at the level of 0.2% improved ADFI/ADG(P<0.05). Ammonia gas production from manure was not significantly affected by treatments. All Natufermen$^{(R)}$ treatments increased in DM, crude ash and phosphorus digestibility(P<0.05). Serum IgG decreased as supplemention level of Natufermen$^{(R)}$ increased(P<0.05). Supplemtation of Natufermen$^{(R)}$ at 0.1% and 0.2% increased fecal Lactobacilli population at 3 wks after feeding treated diets(P<0.05). It is concluded that supplementation of Aspergillers oryzae product Natufermen$^{(R)}$ improved feed conversion ratio and digestibility of DM, crud ash and phosphours. Fecal ammonia gas production was not significantly affected but serum IgG level was decreased and CFU of fecal Lactobacilli was increased at 3 wks after feeding Natufermen$^{(R)}$ supplemented diets.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.1
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• pp.7-17
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• 2014

Molten salt electrorefining process achieves uranium deposits at cathode using an electrochemical processing of spent nuclear fuel. In order to recover pure uranium from cathode deposit containing about 30wt% salt, the adhered salt should be removed by cathode process (CP). The CP has been regarded as one of the bottle-neck of the pyroprocess as the large amount of uranium is treated in this step and the operation parameters are crucial to determine the final purity of the product. Currently, related research activities are mainly based on experiments consequently it is hard to observe processing variables such as temperature, pressure and salt gas behavior during the operation of the cathode process. Hence, in this study operation procedure of cathode process is numerically described by using appropriate mathematical model. The key parameters of this research are the amount of evaporation at the distillation part, diffusion coefficient of gas phase salt in cathode processor and phase change rate at condensation part. Each of these conditions were composed by Hertz-Langmuir equation, Chapman-Enskog theory, and interphase mass flow application in ANSYS-CFX. And physical properties of salt were taken from the data base in HSC Chemistry. In this study, calculation results on the salt gas behavior and optimal operating condition are discussed. The numerical analysis results could be used to closely understand the physical phenomenon during CP and for further scale up to commercial level.

• Journal of Environmental Policy
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• v.8 no.4
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• pp.95-124
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• 2009

This study aims to introduce greenhouse gas emission trading in Korea as a highly cost-effective mechanism for controlling emissions. The Basic Act on Low-Carbon Green Growth will cover methods of emissions allocation, national inventory, and trading systems (i.e. emissions trading platforms, national registry,and clearing and settlement platforms). The Korean emission scheme will be based on the Korean Climate Change Act proposed by the National Assembly and Government with a cap-and-trade scheme. The national allowances will be allocated by the hybrid system. To establish the national inventory, TRADEMARKS (Telemetering System) and emissions factors are effective for greenhouse gas emissions measurement. It will likewise be effective for the national registry to be implemented via a Korean Integrated Registry, the emissions trading platform via the KRX (Korean Exchange), and the clearing and settlement platform via the KSD (Korean Securities Depository). In other words, the KRX will manage product development and marketing for Korean Carbon Financial Instruments (including commodities, futures, and options contracts) listed and admitted to trading on the KRX. All emissions trades will be standardized and cleared by the KSD.

• Journal of the Korean Institute of Gas
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• v.21 no.6
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• pp.52-60
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• 2017

In diffusion process exhaust line during semiconductor manufacturing process, In order to improve the transportation efficiency in the piping by removing "The reaction by-product, $ZrO_2$ and The unreacted material, TEMAZ, TMA, $O_3$, etc" and "Powder being deposited", the piping temperature was raised to $80^{\circ}C$ or more by using the heater jacket, and the bellows at the rear end of the vacuum pump ruptured. So conducted a case study and try to prevent the similar accidents from occurring through case studies. The causes of the accident were analyzed as follows: the inflow of outside air due to the generation of a gap on the suction side of the vacuum pump and heating the pipe with the heater jacket resulted in the overpressure in the pipe due to the volumetric expansion of the gas generated by decomposition of the unreacted TEMAZ, It can be assumed that the most vulnerable bellows of the piping has been ruptured. In order to prevent such accidents, This study is aimed to identify the cause of pipeline rupture accident and to establish safety measures for the prevention of similar accidents by evaluating physical hazards of TEMAZ, which is assumed to be the cause of pipe rupture accident.