• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.353-360
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• 2009

Phosphorus (P) is one of the essential elements of the phospholipids that are involved in the formation of plant cell membranes. Phosphorus is highly immobile in soils and is often a limiting nutrient for plant growth. Phosphorus mobility and availability varies with several factors such as application frequency, placement in the soil, and the amount of irrigation or precipitation. This study was conducted to evaluate the effect of P applications at level of 0, 146, and 293 $kg{\cdot}ha^{-1}$ at four mixing depths (0, 7.6, 15.2, and 22.9 cm )on the growth and establishment of Kentucky bluegrass (Poapratensis L.) in a sand-based system.Grass clipping samples were collectedevery two weeks, dried, and weighed. Total root dry weight, root organic matter, and tissue content of P were measured at the end of the study. Leachate was collected weekly and analyzed for total P concentration. No difference was found between application of P to the surface and to the 7.6 cm mixing depth. However, surface application with 146 and 293 kg $P{\cdot}ha^{-1}$ produced 8-10% and 16-20% more P in tissue than subsurface applications, respectively.

• Food Science and Preservation
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• v.19 no.6
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• pp.866-872
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• 2012

This study was conducted to investigate the changes in physicochemical properties of Spergularia marina Griseb by blanching. The proximate composition, free sugar, free amiao acid, organic acid, vitamin and mineral composition of raw and blanching Spergularia marina Griseb were compared. After blanching treatment, the moisture and carbohydrate contents of Spergularia marina Griseb increased, but the crude protein, crude fat and crude ash contents decreased. Total free sugar content decreased by 62.50% compared with raw Spergularia marina Griseb after blanching, and the reduction of galactose was the largest in free sugars. The raw and blanched Spergularia marina Griseb contained all the essential amino acids, except tryptophan. The total amino acid and essential amino acid contents were reduced by blanching, but the essential amino acid ratios of the raw and blanched Spergularia marina Griseb were similar. The amounts of all the detected organic acids were reduced by blanching, except acetic acid. Spergularia marina Griseb was found to contain high levels of vitamin C, vitamin E, and minerals, but these were reduced by blanching. These results showed that most of the nutrients contained by Spergularia marina Griseb are decrease by blanching. Therefore, the blanching conditions that can reduce nutrient loss of Spergularia marina Griseb must be established.

• Food Science and Preservation
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• v.19 no.6
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• pp.933-938
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• 2012

The quality characteristics of rice wine seed mash and rice wine made with different lactic acid concentrations were investigated. The pH decreased along with the lactic acid concentration. The total titratable acid content of the rice wine seed mash was lowest when 0.5% lactic acid was added, and the ethanol contents of the mash samples were not significant. The results of the measurement of the microorganism number, C (cell numbers of the total bacteria and the lactic acid bacteria), decreased along with the lactic acid concentrations of the mash samples. The yeast cell numbers of the rice wine seed mash samples according to the lactic acid concentrations were high (0.5, 0.3, 1.0, control, and 0.7%, respectively). The pH and total titratable acid levels of rice wine according to the lactic acid concentration were stable during fermentation, according to the increase in the amount of lactic acid. The organic acids in the rice wines were highest in the lactic acid. The rice wines to which lactic acid had been added had lower acetic acid contents than the control. Also, the acetic acid contents decreased along with the lactic acid concentrations, except in the rice wine treated with 1.0% lactic acid. The ethanol contents of the tested rice wines were not significant. All in all, in the sensory evaluation, the rice wines treated with 0.5 and 0.7% lactic acid scored higher than the other treatments.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1220-1225
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• 2011

Anaerobic decomposition of organic materials in flooded rice fields produces methane ($CH_4$) gas, which escapes to the atmosphere primarily by transport through organs of the rice plants such as arenchyma etc., Although the annual amount of methane emitted from a given area is influenced by cultivation periods of rice and organic/inorganic amendments etc., soil type also affects methane emission from paddy soil during a rice cultivation. A field experiment was conducted to evaluate effects of soil type on $CH_4$ emission in two paddy soils. One is a red-yellow soil classified as a Hwadong series (fine, mixed, mesic family of Aquic Hapludalfs), and the other is a gley soil classified as a Shinheung series (fine loamy, mixed, nonacid, mesic family of Aeric Fluvaquentic Endoaquepts). During a flooded periods, redox potentials of red-yellow soil were significantly higher than gley soil. $CH_4$ emission in red-yellow soil ($0.21kg\;ha^{-1}\;day^{-1}$) was lower than that in gley soil ($5.25kg\;ha^{-1}\;day^{-1}$). In the condition of different soil types, $CH_4$ emissions were mainly influenced by the content of total free metal oxides in paddy soil. The results strongly imply that iron- or manganese-oxides of well ordered crystalline forms in soil such as goethite and hematite influenced on a $CH_4$ emission, which is crucial role as a $CH_4$ oxidizers in paddy soil during a rice cultivation.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.2
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• pp.55-69
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• 2011

Use of disposer at the kitchens of Korean apartments is inevitable in treating their foodwaste having a water content of more than 80%. Also we have to ensure that this extra disposer-foodwaste BOD loadings be treated properly by installing/operating a pre-treatment system before this wastewater enters public sewer system. However, the degree of BOD removal should not be excessive since a BOD/N ratio higher than 5 is required for removing N/P at a municipal wastewater treatment plant. The removal of BOD/N in the pretreatment system rather than BOD alone can be an alternative solution in solving this problem. The particles separated by sedimentation, screen or packed-bed can be anaerobically digested at apartment sites to generate biogas that can be used for simple digester heating and to generate volatile fatty acids (VFAs) for nitrogen removal. We suggest that Korean government grants a temporary license (say for 5 years) to foodwaste treatment companies in collaboration with apartment construction companies which may do business and develop various kinds of disposer-foodwaste treatment systems in diverse wastewater discharge systems of Korean apartments.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.41-49
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• 2019

Livestock manure is a significant source for greenhouse gas (GHG) emission, and a huge amount of GHG emission is generated during its storage. In the present work, lowering temperature was attempted to mitigate methane ($CH_4$) emission from cattle manure (CM) with high solid content. CM was stored for 60 d at $15-35^{\circ}C$ ($5^{\circ}C$ interval). $CH_4$ emission reached $63.6{\pm}3.6kg\;CO_2\;eq./ton\;CM$ at $35^{\circ}C$, which was reduced to $51.6{\pm}1.8$, $24.1{\pm}4.4$, $14.9{\pm}0.5$, and $3.7{\pm}0.1kg\;CO_2\;eq./ton\;CM$ at 30, 25, 20, and $15^{\circ}C$, respectively. After storage, 30% of COD reduction was observed in the CM stored at $35^{\circ}C$, while the COD removal decreased to only 6% at $15^{\circ}C$. It was found that only 3-11% of COD removal was done by anaerobic process, while the rest of COD removal was done by aerobic biological process. Methanobrevibacter and Methanolobus were found to be the dominant species in the CM, and the dominance of Methanolobus psychrophilus increased at lower storage temperature. Specific methanogenic activity test results showed that the inhibition by low temperature was temporal.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.13-18
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• 2019

Sewage sludge treatment is increasing every year due to improvement of living and urbanization. However, interest in anaerobic digestion which is one of the recycling technology. There is anaerobic digestion of increasing due to limitations of ocean dumping and final disposal. But, the limit of anaerobic digestion efficiency due to the advanced treatment of sewage has been limited, and studies for solubilization technology have been actively conducted. Therefore, in this study, we aimed to investigate the variation of generation of scum and the solubilization efficiency in the application of pre-treatment of ozone reaction and the change of properties of digested sludge with wet milling. There are results of VS/TS increased by 4.4% and $SCOD_{cr}/TCOD_{cr}$ increased by 9.4% by wet milling alone. In addition, the increase of the specific surface area due to which the reduction of the particle size of the solid content of the sludge in the ozone reaction caused by wet milling decreased the generation rate of scum at 14.3% and increased VS/TS at 2.1%, compared with the ozone reaction alone. From these results, it is expected that the application of wet milling can be increased the contact efficiency with solids in the sludge during ozone reaction with suppress scum and increase the efficiency of the subsequent process in anaerobic digestion.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.393-407
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• 2019

In this study, we prepared lignocellulosic artificial soil that contains Bacillus subtilis (peat moss/perlite/ steam-exploded oak wood/microbial culture = 3:1:3:3, w/w/w/w) for use in the restoration of damaged soil areas. The prepared lignocellulosic artificial soil was mixed with soil at ratios of 0%, 25%, 50%, 75%, and 100%. These mixed soils were then applied to fields, and the resultant physicochemical properties and their effects on the plant growth of Lespedeza cyrtobotrya were observed. The mixture of the prepared artificial soils (mixed at ratios of 25%-100%) with soil had a bulk densities of <$0.04g/cm^3$, porosities of >85%, pH values between 4.3 and 4.7, electrical conductivities of <0.5 dS/m, C/N ratios between 15.0 and 26.5, organic matter content between 23.6% and 43.2%, and bacterial densities between $157{\times}10^6$ and $624{\times}10^6CFU/g$. In addition, the prepared artificial soils mixed with soil at ratios of 25%-50% exhibited higher plant growth rates for L. cyrtobotrya compared with the control. Overall, we identified positive correlations between the plant growth of L. cyrtobotrya and soil bulk density, porosity, water-holding capacity, C/N ratio, organic matter, and bacterial densities.

• Journal of the Korean Electrochemical Society
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• v.21 no.4
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• pp.80-87
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• 2018

Safety issues in Li-ion battery system have been prime concerns, as demands for power supply device applicable to wearable device, electrical vehicles and energy storage system have increased. To solve safety problems, promising strategy is to replace organic liquid electrolyte with non-flammable solid electrolyte, leading to the development of all-solid-state battery. However, relative low conductivity and high resistance from rigid solid-solid interface hinder a wide application of solid electrolyte. Composite electrolytes composed of organic and inorganic parts could be alternative solution, which in turn bring about the increase of conductivity and conformal contact at physically rough interfaces. In our study, composite electrolytes were prepared by combining poly(ethylene oxide)(PEO) and $Li_7La_3Zr_2O_{12}$ (LLZO). The crystallinity, morphology and electrochemical performances were investigated with the control of LLZO contents from 0 wt% to 50 wt%. From the results, it is concluded that optimum content and uniform dispersion of LLZO in polymer matrix are significant to improve overall conductivity of composite electrolyte.

• Journal of Sensor Science and Technology
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• v.28 no.1
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• pp.41-46
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• 2019

In order to develop novel thermal imaging materials for microbolometer applications, $[(Ni_{0.3}Mn_{0.7})_{1-x}Cu_x]_3O_4$ ($0.18{\leq}x{\leq}0.26$) thin films were fabricated using metal-organic decomposition. Effects of Cu content on the electrical properties of the annealed films were investigated. Spinel thin films with a thickness of approximately 100 nm were obtained from the $[(Ni_{0.3}Mn_{0.7})_{1-x}Cu_x]_3O_4$ films annealed at $380^{\circ}C$ for five hours. The resistivity (${\rho}$) of the annealed films was analyzed with respect to the small polaron hopping model. Based on the $Mn^{3+}/Mn^{4+}$ ratio values obtained through x-ray photoelectron spectroscopy analysis, the hopping mechanism between $Mn^{3+}$ and $Mn^{4+}$ cations discussed in the proposed study. The effects of $Cu^+$ and $Cu^{2+}$ cations on the hopping mechanism is also discussed. Obtained results indicate that $[(Ni_{0.3}Mn_{0.7})_{1-x}Cu_x]_3O_4$ thin films with low temperature annealing and superior electrical properties (${\rho}{\leq}54.83{\Omega}{\cdot}cm$, temperature coefficient of resistance > -2.62%/K) can be effectively employed in applications involving complementary metal-oxide semiconductor (CMOS) integrated microbolometer devices.