• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.285-290
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• 1997

This study was conducted to develop labor-saving pesticide-fertilizer mixed formulation through a single application of mixed formulation of an insecticide imidacloprid coated on a slow release urea. The release of both total nitrogen and imidacloprid into water was delayed with increasing adhesive.Imidacloprid was released out 95% within 24 hours, whereas total nitrogen released in mixed formulation until 40 days was released less extent by increasing adhesive. There was no difference between pesticide-fertilizer mixed formulation and coated urea thereafter. The content of $NH_4-N$ in the soil treated with pesticide and urea seperating was higher until 10 days but gradually decreased compare to that of pesticide-fertilizer mixed formulation or coated urea. The population density of nitrate reducing bacteria and denitrifying bacteria in soil after treatment were lower in the pesticide-fertilizer mixed formulation and coated urea than those of pesticide and urea separate treatment. The residue of imidacloprid in soil was slightly higher in the treatment of pesticide alone than the pesticide-fertilizer mixed formulation and pesticide and urea seperating treatment. The population and control efficacy of small brown planthopper, Laodelphax striatellus, were not significance different among treatments.

• Journal of Animal Science and Technology
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• v.60 no.11
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• pp.27.1-27.8
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• 2018

Background: Enteric methane ($CH_4$) accounts for about 70% of total $CH_4$ emissions from the ruminant animals. Researchers are exploring ways to mitigate enteric $CH_4$ emissions from ruminants. Recently, nano zinc oxide (nZnO) has shown potential in reducing $CH_4$ and hydrogen sulfide ($H_2S$) production from the liquid manure under anaerobic storage conditions. Four different levels of nZnO and two types of feed were mixed with rumen fluid to investigate the efficacy of nZnO in mitigating gaseous production. Methods: All experiments with four replicates were conducted in batches in 250 mL glass bottles paired with the ANKOM$^{RF}$ wireless gas production monitoring system. Gas production was monitored continuously for 72 h at a constant temperature of $39{\pm}1^{\circ}C$ in a water bath. Headspace gas samples were collected using gas-tight syringes from the Tedlar bags connected to the glass bottles and analyzed for greenhouse gases ($CH_4$ and carbon dioxide-$CO_2$) and $H_2S$ concentrations. $CH_4$ and $CO_2$ gas concentrations were analyzed using an SRI-8610 Gas Chromatograph and $H_2S$ concentrations were measured using a Jerome 631X meter. At the same time, substrate (i.e. mixed rumen fluid+ NP treatment+ feed composite) samples were collected from the glass bottles at the beginning and at the end of an experiment for bacterial counts, and volatile fatty acids (VFAs) analysis. Results: Compared to the control treatment the $H_2S$ and GHGs concentration reduction after 72 h of the tested nZnO levels varied between 4.89 to 53.65%. Additionally, 0.47 to 22.21% microbial population reduction was observed from the applied nZnO treatments. Application of nZnO at a rate of $1000{\mu}g\;g^{-1}$ have exhibited the highest amount of concentration reductions for all three gases and microbial population. Conclusion: Results suggest that both 500 and $1000{\mu}g\;g^{-1}$ nZnO application levels have the potential to reduce GHG and $H_2S$ concentrations.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.3
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• pp.193-198
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• 2013

In general, boron recovery of 40-90% could be achieved by Reverse Osmosis (RO) membranes in neutral pH condition. As an emerging technology, Forward Osmosis (FO) membrane has attracted growing interest in wastewater treatment and desalination. The objective of this study is to evaluate the possibility of the boron removal in radioactive liquid waste by FO. In this study, the performance of FO was investigated to remove boron in the simulated liquid waste as the factors such as pH, osmotic pressure, ionic strength of solution, etc. The pH of feed solution is a major operating parameter which strongly influences to the permeation of boron and more than 80% of boron content can be separated when conducted at pH values less than 7. The water flux is not influenced but the boron flux and permeation rate tends to decrease in the low salt concentration of 1,000 mg/L. The boron flux increases linearly, but the permeation ratio of reducing boron is nearly constant even with changes in the draw solution concentration.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.2
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• pp.124-132
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• 2018

This research presents the results of an investigation on the characteristic of multi-component blended high fluidity mortars. The binder was blended ordinary Portland cement(OPC), ground granulated blast furnace slag(GGBFS), calcium sulfoaluminate(CSA) and ultra rapid setting cement(URSC). The GGBFS was replaced by OPC from 30%(P7 series), 50%(P5 series) and 70%(P3 series), CSA and URSC was 10% or 20% mass. The superplasticizer of polycarboxylate type were used. A constant water-to-binder ratio(w/b)=0.35 was used for all mixtures. Test were conducted for mini slump, setting time, V-funnel, compressive strength and drying shrinkage. According to the experimental results, the contents of superplasticizer, V-funnel and compressive strength increases with an increase in CSA or URSC contents for all mixtures. Moreover, the setting time and drying shrinkage ratio decrease with and increase in CSA or URSC. CSA decreased dry shrinkage but URSC had less effect. However, the mixed binders of CSA and URSC had a large effect of reducing drying shrinkage by complementary effect. This is effective for improving the initial strength of URSC, and CSA is effective for the expansion and improvement of long-term strength.

• Restorative Dentistry and Endodontics
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• v.32 no.4
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• pp.313-326
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• 2007

The purpose of this study was to prove that an intermediate resin layer (IRL) oan increase the bond strength to dentin by reducing the permeability of single-step adhesives. Flat dentin surfaces were created on buccal and lingual side of freshly extracted third molar using a low-speed diamond saw under copious water flow. Approximately 2.0 mm thick axially sectioned dentin slice was abraded with wet #600 SiC paper. Three single-step self-etch adhesives; Adper Prompt L-Pop (3M ESPE, St Paul, MN, USA), One-Up Bond F (Tokuyama Corp, Tokyo, Japan) and Xeno III (Dentsply, Konstanz, Germany) were used in this study. Each adhesive groups were again subdivided into ten groups by; whether IRL was used or not; whether adhesives were cured with light before application or IRL or not; the mode of composite application. The results of this study were as follows; 1. Bond strength of single-step adhesives increased by an additional coating of intermediate resin layer, and this increasement was statistically signigicant when self-cured composite was used (p < 0.001). 2. When using IRL, there were no difference on bond strengths regardless the curing procedure of single-step adhesives. 3. There were no significant difference on bond strengths between usage of AB2 or SM as an IRL. 4. The thickness of Hybrid layer was correlated with the acidity of adhesive used, and the nanoleakage represented by silver deposits and grains was examined within hybrid and adhesive layer in most of single-step adhesives. 5. Neither thickness of hybrid layer nor nanoleakage were related to bond strength.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.210-224
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• 2003

Sulfate reduction is a microbiological process which occurs ubiquitously in anaerobic marine environment. Sulfate reducing bacteria play a significant role in anaerobic decomposition of organic matter and regeneration of inorganic nutrients which supports the primary production in the water column (i.e., benthic-pelagic coupling) and, in special case, could be responsible for the harmful algal bloom in the coastal marine environment. Summary of the sulfate reduction rates reported in various marine sedimentary environments revealed that supply of organic substrates and presence of various electron acceptors (i.e., $O_2$, NO$_{3}$$^{[-10]}$ , Fe(III) and Mn(IV), etc.) for other aerobic and anaerobic respiration directly affect the sulfate reduction rate and relative significance of sulfate reduction in organic matter mineralization. Significance of temperature, macrophytes and bioturbation is discussed as factors controlling supply of organic substrates and distribution of electron acceptors. Finally, we suggest studies on the anaerobic microbiological processes associated with biogeochemical element cycles in the coastal environments of Korea where massive operation of organic enriched fish cage farm, frequent occurrence of toxic algal bloom and hypoxia and conservation of tidal flat are of major environmental issues.

• Journal of Animal Environmental Science
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• v.18 no.sup
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• pp.41-46
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• 2012

This study was performed to test the effect of horseradish powder in fattening pig diet on odorous compound concentration from manure. Twenty fattening boars [Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] weighing an average body weight of $68.4{\pm}4.95}$ kg were randomly assigned to one of 4 treatments (horseradish level in diets: 0, 0.01, 0.02, 0.03%) based on their body weight. This experiment was a randomized complete block (RCB) design using 5 pigs per treatment with 1 pig per metabolizable cage. Pigs were fed experimental diet (amount proportional to 3% of their body weight) twice a day (09:00 and 16:00) for 7 d after having 14 d adaptation period. Experimental diets were mixed with water by 1:2.5 v/v. Concentration of volatile fatty acids (VFAs) was highest (p<0.05) when pigs fed diet with 0.02% horseradish powder. Level of phenol compounds including phenol and p-cresol were decreased (p<0.05) in 0.01~0.02% horseradish treatment group compared with control group. Concentration of indoles including indole and skatole was lowest (p<0.05) in 0.03% horseradish treatment group compare to others. Therefore, results from our current study suggest that the optimal levels of horseradish powder in diet for reducing phenol and indole compounds in pig manure were 0.02 and 0.03%, respectively.

• Journal of Life Science
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• v.12 no.3
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• pp.349-356
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• 2002

In order to observe the bioactivity of ovariectomized rats, nonovariertoized (sham) group, ovariectomized (Ovx) group, ovariectomized ginseng total saponin (GTS)-treated (Ovx+ GTS) group and ovariectomized ginseng water extract (GW)-treated (Ovx+CW) group were made. We measured AST (L-aspartate aminotransferase) and ALT (L-alanin aminotransferase) in sera, and MDA (malondialdehyde:lipid peroxidation), SOD (superoxide dismutase), catalase, total-glutathione (GSH + GSSG) and GPx (glutathione peroxidase) in liver tissue total homogenates of rat. AST activity of serum in Ovx group was 2.11 times increased, but ALT activity was not changed compared to Sham group. In AST activity, they tend to decrease significantly in each substance such as GTS and GW administered group. Lipidperoxides of each fraction in Ovx group were highly increased compared to Sham group. Extracts of ginseng-treated group markedly inhibited lipid peroxidation by 62% ∼72%. And as the result of the measurements of SOD, catalase, total-glutathione and GPx which are antioxidant enzyme, antioxidant enzymes in Ovx group much lower than in Sham group. But they were significantly increased in each substance such as GTS and GW, administered group. Based on the results, it is supposed that more produced free radicals decreased antioxidant enzyme. And it is also thought that extracts of ginseng can inhibit aging by reducing antioxidant enzyme.

• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.183-189
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• 2010

This study examined the quality characteristics and antioxidant activities of cookies added Pleurotus eryngii powder. There were no significant differences in bulk density or water content between the doughs. Spread factors and leavening rates of cookies decreased with increasing Pleurotus eryngii powder content. However, the loss rates of cookies showed no significant differences. L values decreased with increasing Pleurotus eryngii powder content while a values were gradually increased. b values showed no significant differences among the samples. Hardness, total phenol compound content, ferric reducing antioxidant power (FRAP) and DPPH radical scavenging activity of cookies were significantly increased with increasing Pleurotus eryngii powder content. In a descriptive test, the color, flavor, palatability, hardness and graininess were all increased with increasing Pleurotus eryngii powder content. In a preference test, color and flavor were the highest in the 10% group without significant differences. Texture was preferred in the control-20% groups without significant differences. However, taste and overall acceptability were the highest in the 10% group.

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.156-161
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• 2020

This study was designed to evaluate the quality characteristics and antioxidant activities of noodles containing Allium senescens L. powder (0, 2, 4, 6, and 8%). With an increase in the consumption of Allium senescens L., there was a decrease in pH (p<0.001), water absorption ratio, volume expansion ratio, and turbidity (p<0.05). The colorvalue showed that the addition of Allium senescens L. decreased the L and b values. On the other hand, a value was increased (p<0.001). The mechanical texture of the noodles containing Allium senescens L. was decreased by the addition of Allium senescens L. considering its hardness and chewiness; however, it increased the adhesiveness, springiness, and cohesiveness (p<0.001). In the sensory evaluation, the noodles with 4% Allium senescens L. powder showed the best results (p<0.001). The total polyphenol content, total flavonoid content, DPPH radical scavenging, and reducing power were increased upon addition of Allium senescens L. powder (p<0.001).