• Journal of Agricultural Extension & Community Development
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• v.16 no.2
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• pp.363-384
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• 2009

This study aimed at finding directions for Korean agriculture to establish a new paradigm of sustainable development. Various problematic issues and concerns in the environment necessitate the transformation of Korea's development paradigm from unconditional growth to "Green Growth" through new policies on green value and review of various advanced researches. In this research, the environment-friendly agriculture's problems, particularly in agribusiness were analyzed. Drawing from Michael Porter's Value Chain Analysis, this research developed a value chain model in agriculture that reflects the environment and the present situations. Future directions in the agriculture sector were also discussed. Korea realized food self-sufficiency through the green revolution in the early 1970s. However, a lot of problems have also occurred, including ground and water pollution and the destruction of ecosystems as a result of the overuse of pesticides and chemical fertilizers. In the late 1970s, the growing interest on environment-friendly agriculture led to the introduction of sustainable methods and techniques. Unfortunately however, these were not innovative enough to foster environment-friendly agriculture. Thereafter, the consumers' distrust on agricultural products has worsened and concerns about health have increased. In view of this, the Ministry of Food, Agriculture, Forestry and Fisheries introduced in December 1993 a system of Quality-Certified Products for organic and pesticide-free agri-foods. Although a fundamental step toward the sustainability of the global environment, this system was not enough to promote environment-friendly agriculture. In 2008, Korea's vision is for "Low Carbon Green Growth" to move forward while also coping with climate change. But primary sectors in a typical value chain do not consider the green value of their operations nor look at production from an environmental perspective. In order to attain sustainable development, there is a need to use less resources and energy than what is presently used in Korean agricultural and value production. The typical value chain should be transformed into a "closed-loop" such that the beginning and the end of the chain are linked together. Such structure allows the flow of materials, products and even wastes among participants in the chain in a sustained cycle. This may result in a zero-waste sustainable production without destroying the ecosystem.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.417-420
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• 2012

This study is about reduction reaction making 2, 4-dinitrotoluene (2, 4-DNT) to 2, 4-toluene diisocyanate (2,4-TDI) with Pd/$SiO_2$. Catalytic systems based on Pd/$SiO_2$ at about $200^{\circ}C$ and under 100 bars of carbon monoxide. We studied the effect of pyridine on the yield of the TDI. TDI was not created without pyridine, but created with pyridine, at the reaction result. According to research, homogeneous synthesis of TDI with direct carbonylation, palladium and pyridine complexion is known to catalyze. When adding pyridine the reason of TDI synthesis is palladium leaching, ICP-AES was performed to confirm it. As a result, the proportion of Pd loaded in $SiO_2$ was decreased 52% than before, after the reaction by adding 20 vol% pyridine. Generating TDI by adding pyridine might be the effect of the complex ion, which is composed of leached palladium and pyridine.

• KSBB Journal
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• v.28 no.1
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• pp.60-64
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• 2013

Two strains were isolated from the traditional Deep Blue Sediment Dye of Polygoum tinctoria, Niram, and temporarily named Niram A and Niram B, respectively. The phylogenetic analysis revealed that strain Niram A and B were closely related to the members of the genus Comamonas and Microbacterium, respectively. Strain Niram A exhibited the highest 16S rRNA gene sequence similarity to C. aquatica LMG $2370^T$ (98.06%). Strain Niram B showed 100% homology with M. oxydans DSM 20578T and M. maritypicum DSM $12512^T$. The growth of the strain Niram A and B was not inhibited in Niram medium containing high calcium concentration without free sugar as carbon source. The reducing Niram is greenish. Therefore, the reducing ability on the Niram of the strains Niram A and B were determined with the color difference of the $a^*$ values of Niram fermented-fluids. The $a^*$ value indicates the level of redness (positive value) or greenness (negative value). The green color is increasing towards the negative value. In all samples fermented for 10 days, the $a^*$ values among samples were no significant difference. However, samples fermented for 15 days have an appreciable change. After fermentation for 15 days, the control Niram sample had $-3.96{\pm}0.02$ of the $a^*$ value. On the other hand, the Niram samples fermented with the strain Niram A and B showed $-4.20{\pm}0.02$ of the $a^*$ value and $-7.86{\pm}0.03$ of the $a^*$ value, respectively. In the reducing ability on the Niram, the strain Niram B was significantly better than the strain Niram A.

• Membrane Journal
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• v.27 no.6
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• pp.499-505
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• 2017

The increasing number of natural disasters resulting from anthropogenic greenhouse gas emissions has prompted the development of a gas separation membrane. Carbon dioxide ($CO_2$) is the main cause of global warming. Organic polymeric membranes with inherent flexibility are good candidates for use in gas separation membranes and poly(dimethyl siloxane)(PDMS) specifically is a promising material due to its inherently high $CO_2$ diffusivity. In addition, poly(vinyl pyrrolidine)(PVP) is a polymer with high $CO_2$ solubility that could be incorporated into a gas separation membrane. In this study, poly(dimethyl siloxane)-poly(vinyl pyrrolidine)(PDMS-PVP) comb copolymers with different compositions were synthesized under mild conditions via a simple one step free radical polymerization. The copolymerization of PDMS and PVP was characterized by FTIR. The morphology and thermal behavior of the produced polymers were characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Composite membranes composed of PDMS-PVP on a microporous polysulfone substrate layer were prepared and their $CO_2$ separation properties were subsequently studied. The $CO_2$ permeance and $CO_2/N_2$ selectivity through the PDMS-PVP composite membrane reached 140.6 GPU and 12.0, respectively.

• KSBB Journal
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• v.20 no.1 s.90
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• pp.21-25
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• 2005

Paraquat, a widely used herbicide, has been suggested as a potential risk factor for Parkinson's disease. Heme oxygenase-1(HO-1), a marker for oxidative stress and endoplasmic reticulum(ER) stress, is known to catalyze heme to biliverdin, carbon monoxide and free iron in response to various stimuli. Here we show that paraquat activates HO-1 expression in a time-and dose-dependent manner in substantia nigra(SN) dopaminergic neuronal cells. Activation of Ho-1 by paraquat was regulated primarily at the level of gene transcription. Deletion analysis of the promoter and the 5' distal enhancers, E1 and E2, of the HO-1 gene revealed that the E2 enhancer is a potent inducer of the paraquat-dependent Ho-1 gene expression in dopamninergic neuronal cells. Mutational analysis of the E2 enhacer further demonstrated that the transcription factor activator protein-1(AP-1) plays an important role in mediating paraquat-induced HO-1 gene transcription. Moreover, using specific inhibitors of the mitogen-activated protein kinases(MAPKs), we investigated the role of paraquat and MAPKs for HO-1 gene regulation in dopaminergic cells. The c-Jun N-terminal kinase(JNK) inhibitor SP600125 significantly suppressed the expression of HO-1 by paraquat. All these results demonstrate that induction of HO-1 by paraquat requies the activation of the AP-1 and JNK pathway.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.1
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• pp.1-6
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• 2012

Down Stream K River has high COD (4-10 mg/L) and high $NH_3$-N concentration (3.5 mg/L during winter period). Although $NH_3$-N itself is not reported harmful at this level, it must be removed to meet drinking water standard (0.5 mg/L). We constructed a pilot plant modifying the processes of conventional drinking water facilities. Prechlorination and powdered activated carbon (PAC) dechlorination was adopted prior to a flocculation tank to remove ammonia and prevent disinfection byproducts (DBPs) formation. Also, GAC processes was included after sand filter to remove residual DOC. This pilot having a capacity of 36 ton/day was operated for one year. The GAC processes were successful to remove ammonia and many organic pollutants (DOC, MBAS, UV-254 nm absorbance, etc). Influent DOC concentrations were very high as 3~6 mg/L throughout the plant operation. It was impossible to achieve 1.0 mg/L effluent DOC, indicating that bed depth (2 m) should be increased to achieve more strict DOC quality standards. When $Cl_2$ dose was well controlled ($Cl_2/NH_3$-N ratio 10~11 on a weight basis), $NH_3$-N removal was 98% and THMs was very low possibly due to low free residual chlorine and PAC dechlorination.

• Journal of Wetlands Research
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• v.20 no.1
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• pp.54-62
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• 2018

Nutrients generated from various land uses lead to eutrophication during the influx of water, and it is necessary to apply the LID techniques to reduce nutrients from nonpoint sources in order to mitigate the occurrence of the algal bloom. This study was carried out to derive the design factors of hybrid artificial wetland (HCW) to increase the removal efficiency of nutrients. HCW system was constructed in the year 2010 for the treatment of rainfall runoffs from parking lots and roads composed of 100% impervious floors in the Cheonan campus of Kongju University. The average nutrients removal efficiency of TN and TP was 74% and 72%, respectively. Both TN and TP removal efficiencies were higher than those of free surface wetlands and subsurface flow wetlands due to activated physical and ecological mechanisms. The critical design parameters for the efficient nutrients removal in the artificial wetlands were the ratio of the surface area to the catchment area (SA/CA), land use, the rainfall runoff, and the rainfall intensity. The optimal carbon to nitrogen (C/N) ratio was estimated at 5: 1 to 10.3: 1. The results of this study can be applied to the efficient design of hybrid artificial wetlands to treat nutrients in urban runoff with high efficiency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.18-25
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• 2019

Recently, micro-grids based on a CVCF inverter have been replacing diesel generators to reduce CO2 emissions in island areas with the increase of renewable energy sources. Stable operation methods are also being researched. These micro-grids may cause energy sinking if the total output of renewable energy sources is larger than the total customer loads. In the case of energy sinking, the voltage of a CVCF battery could rapidly increase according to the condition of SOC, and blackout could occur in the micro-grid due to the operation of a protection device in a CVCF inverter. Therefore, this paper analyzes the operation characteristics of a CVCF-inverter-based micro-grid when energy sinking occurs and proposes a transient operation strategy to prevent shut-down of the CVCF inverter. A test device of a 30-kW CVCF-inverter-based micro-grid was implemented, and the transient operation characteristics for the energy sinking phenomenon are presented. The simulation results confirm that blackout can be properly prevented according to the conditions of SOC and voltage in a CVCF battery.

• Membrane Journal
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• v.29 no.2
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• pp.88-95
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• 2019

Hydrocarbons containing carbon double bonds are generally called olefins and it is extensively used in petro-chemical industry as essential base material. Especially, olefins are essential in polymer synthesis and thus the effective separation and purification of olefins from gas mixture are very important and it gives significant positive effect on the future industrial development. In this study, we fabricated polymeric composite membrane based on poly(1-trimethylsilyl-1-propyne) (PTMSP) for propylene/nitrogen separation and enhancement of its separation performance by grafting amphiphilic copolymer. Furthermore, to accelerate facilitated transport for propylene molecules, Ag salt ($AgBF_4$) and ionic liquid ($EMIM-BF_4$) was incorporated to polymer composite membranes. The neat PTMSP membrane exhibited extremely high gas permeance and low gas selectivity due to its high free volume. To address this issue, PTMSP was grafted with poly(oxyethylene glycol methacrylate) (POEM) and poly(ethylene glycol) behenyl ether methacrylate (PEGBEM). Additionally, the additives such as $AgBF_4$ and $EMIM-BF_4$ further increased the propylene permeance, resulting in increment of propylene/nitrogen selectivity.

• Korean Journal of Organic Agriculture
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• v.27 no.1
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• pp.65-76
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• 2019

Bacillus genus are found abundantly in various sites and their secondary metabolites were used as potential agents in agriculture, notably plant growth promoting and bio-control. The objective of this study was to develop the culture conditions of GH1-13 strain including higher cell growth, stable endospore-forming and enhancement of potential agents which are related with plant growth promoting and phytopathogen suppression. The optimal carbon and nitrogen sources were determined by glucose and soy bean flour, respectively, then resulted in $7.5{\times}10^9cells/mL$, $6.8{\times}10^9\;endospore\;cells/mL$ and sporulation yield of 90% after 30 h cultivation in 500 L submerged fermenter at $37^{\circ}C$, pH 7.0. Cells and cell-free supernatant of GH1-13 strains showed the potent antifungal activity against phytopathogenic fungi of Colletotrichum gloeosporioides. It was also confirmed that indole-3-acetic acid (IAA) production of GH1-13 strain was greatly increased by addition of 0.3% tryptophan.