• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.351-356
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• 2009

Growth, milled rice yield and edible quality of rice in naturally reseeded Chinese milk vetch(CMV)-rice cropping system was compared with those in rice mono cropping on silty loam soil in Milyang from 2006-2008. Practicing natural reseeding technology recorded high CMV reseeding stand ranging from 565-805 plants $m^{-2}$ and resulting in the production of 13.0-17.0 kg N/10a from the CMV plant biomass which is greater than the recommendation rate of 9 kgN/10a. The plant height of rice plant grown in natural reseeding field is shorter at tillering stage but it was similar to the rice mono cropping at later stage. Dry matter production had similar trend to plant height. On the other hand, the leaf color in naturally reseeded CMV-rice cropping system was similar to the rice mono cropping up to panicle heading stage but it was high at mature stage, indicating that the nitrogen was provided by the CMV decomposition until later stage of rice. The yield components such as culm number $m^{-2}$ was greater and 1,000-brown rice weight was heavier than those of rice mono cropping but the ripened grain ratio was lower in naturally reseeded CMV-rice cropping system. Milled rice yield of naturally reseeded CMV-rice cropping system was similar to that of rice mono cropping. However, head rice percentage of milled rice was lower due to low ripened grain ratio. This result indicates that natural CMV reseeding technology can completely replace chemical fertilizer in CMV-rice cropping system.

• Journal of Animal Environmental Science
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• v.11 no.2
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• pp.117-124
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• 2005

Livestock manure has been utilized as fertilizer, and trying to make resources natural circulation of organic material. This experiment was conducted to investigate the effect of application level of swine slurry on agronomic characteristics and yield of silage corn and $NO_3-N$ content of soil for three years in the experimental field of Grassland and Forage Crops Division, National Livestock Research Institute. Summary of the results were as follows. The experiment was conducted according to a randomized complete block design. Six treatments were non fertilizer(NF), chemical fertilizer(CF), $100\%$ swine slurry(SS100), $150\%$ swine slurry(SS150), $200\%$ swine slurry(SS200) and mixture fertilizer(MF, $100\%$ swine slurry + $50\%$ chemical fertilizer) with three replications. The application level of swine slurry(SS) $100\%$ was highest in Brix as $8.6^{\circ}$ and stay green was as swine slurry application increased. Deficiency of plant, plant height, ear height and lodging were increased in above $100\%$ swine slurry application level. Dry matter yield was decreased in SS 100 but increased in SS 150 and SS 200. Significant effect was observed for all treatments. The content of $NO_3-N$ in infiltration water was high in above swine slurry nitrogen $150\%$ but that content in run off water was very small. Conclusively, application to swine slurry below $150\%$ would be recommended to produce higher yield and to conserve environment in corn field.

• Journal of Soil and Groundwater Environment
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• v.11 no.1
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• pp.14-22
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• 2006

Laboratory column experiment for simultaneous removal of Cd and Cr(VI) were conducted using newly developed material of Fe-loaded zeolite having both reduction ability and sorption capacity. The solution containing Cd and Cr(VI) was injected into the column and the breakthrough curves (BTCs) for the contaminants were observed at the effluent port. Cd breakthrough was not initialized until Cr(VI) breakthrough was completed. Therefore it could be concluded that overall efficiency of Fe-loaded zeolite should be determined by the reactivity for Cr(VI). The relative concentration of Cr(VI) BTC increased to the unit value while initial breakthrough was delayed and the propagation of breakthrough was slowed. In order to quantitatively describe the shape of Cr(VI) BTC, new parameters of ${\alpha}\;and\;{\beta}$ designated to be shape parameters, were defined and applied in contaminant transport concentration. These parameters were employed to represent the degree of initial breakthrough delay and the degree of breakthrough propagation, respectively. As initial contaminant concentration increased, ${\alpha}$ decreased, which indicated the delay of BTC's initiation. And as initial contaminant flow rate increased, ${\beta}$ decreased, which represented the faster propagation of the BTC. From these results, Fe-loaded zeolite was found to be an effective reactive material for PRBs against heavy metals having different ionic forms in groundwater. And it could be expected that as groundwater flows faster, the propagation of breakthrough would be faster and as contaminant concentration is higher, the initial point of breakthrough would appear earlier.

• The Journal of Korean Society for Radiation Therapy
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• v.17 no.2
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• pp.133-140
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• 2005

Purpose : This test is designed to identify the validity of treatment plan by implementing real-time dosimetry by means of dose that is absorbed into PTV and OAR when preparing doses of 3D and POP plans. Materials and Methods : In treatment. error can be calculated be comparing Exp. Dose with the actual dose, which has been converted from 'the reading value obtained by placing diode detector on the area to be measured'. Same test can be repeated using Alderson-Rando phantom. Results : Errors were found: A patient(POP plan): 197.6/199=-1.2%, B patient(3D-plan): 199.9/198.7=+0.6%, C patient: 196/200=-1.5%. In addition, considering the resulted value of measuring OAR besides target-dose for C patient showed 96/200, representing does of 47%, the purpose of protection was judged to be duly accomplished. Also it was acknowledged the resulted value of -3.7% met the targeted dose within the range of ${\pm}5%$. Conclusion : Aimed for identifying the usefulness of pre-treatment dose measurement using diode detector, this test was useful to evaluate the validity of curing because it resulted in the identification of category to be protected as well as t dose. Moreover, it is thought to have great advantage in ascertaining the dose of target, dose of which is not calculated yet. Similar to L-gram before treatment, this test is thought to be very effective so that it can bring great advantages in the aspects such as validity of curing method and post-treatment plan as well.

• The Korean Journal of Mycology
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• v.2 no.1
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• pp.1-6
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• 1974

1. The mycelial growth and sporulation of Mycogone perniciosa was compared on modified Czapek's media deficient in carbon source, nitrogen source, K,Mg, P or the heavy metal elements. The mycelial growth was significantly reduced in solution cultures lacking Mg, K or P and only a trace of growth occurred in solutions lacking carbon source or nitrogen source. Most sparse sporulation and smaller chlamydospores than on any of deficient agar media occurred on agar media dificient in carbon source or nitrogen source. 2. In both potato dextrose agar and malt extract solution, growth of the fungus was optimum at $25^{\circ}C$, and undetectable at $10^{\circ}C$ and $35^{\circ}C$. 3. Optimum pH for growth of this fungus was 7.0. 4. This fungus was killed in soil when exposed to $50^{\circ}C$ or higher for 20 minutes or more.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.64-72
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• 1980

Industrial wastes from pulp and food plants were treated with microorganisms to clarify organic waste-water and to produce cells as animal feed, and results were summarized as follows. (1) Waste-water from pulp, beer, bread yeast, and ethanol distillation plants contained $1.4{\sim}1.5%$ of total sugar, $0.25{\sim}0.35%$ nitrogen, and biological oxygen demand (BOD) was $400{\sim}25,000$, chemical oxygen demand (COD), $500{\sim}28,000$, and pH, $3.8{\sim}7.0$. The BOD and COD were highest in waste-water from ethanol distillation plants among others. (2) Bacterial and yeast counts were $4{\times}10^4-1{\times}10^9,\;2{\times}10^2-7{\times}10^4/ml$ in waste-water. (3) Bacteria grew better in pulp waste and yeasts in beer, bread yeast, and ethanol distillation waste. (4) Saccharomyces cerevisiae SAFM 1008 and Candida curvata SAFM 70 were the most suitable microorganisms for clarification of ethanol distillation waste. (5) When liquid and solid waste from ethanol distillation were treated with microbial cellulase, xylanase, and pectinase, solid waste was reduced by 36%, soluble waste was increased, and recuding sugar content was increased by 1.3 times which provided better medium than untreated waste for cultivation of yeasts. (6) Optimum growth conditions of the two species of yeast in ethanol distillation waste were pH 5.0, $30^{\circ}C$, and addition of 0.2% of urea, 0.1% of $KH_2PO_4$ and 0.02% of $MgSO_4$. (7) Minimum number of yeast for proper propagation was $1.8{\times}10^5/ml$. (8) C. curvata70 was better than cerevisae for the production of yeast cells from ethanol distillation waste treated with microbial enzymes. (9) S. cerevisiae produced 16 g of dried cell per 1,000ml of ethanol distillation waste and reduced BOD by 46%. C. curvata produced 17.6g of dried cell and reduced BOD by 52% at the same condition. (10) Yeast cells produced from the ethanol distillation waste contained 46-52% protein indicating suitability as a protein source for animal feed.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.2
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• pp.59-65
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• 1999

Both the groundwater changes due to different pumping rates and the geochemistry of thermal waters in the Suanbo area are considered in this study. The observation of groundwater level change since 1991 shows that the change is directly correlated with pumping rates of thermal waters and reveals the retardation of ca. 5 weeks after pumping. The hydrogeological aquifer in the area is under reducing condition. The thermal waters are of Na-HCO$_3$ type. and are alkaline (pH=8.5∼8.7) with low TDS values (274∼284 mg/l) and high concentrations of Na (68∼72 mg/l). F (6.4∼8.9 mg/l), and HCO$_3$(136∼146 mg/l). Oxygen and hydrogen isotope ratios of thermal water indicate a meteoric water origin. The activities of Rn-222 and Ra-226 in both thermal water and local groundwater were determined to delineate possible geochemical controls on the Rn-222 and Ra-226. The Rn-222 concentrations are several orders of magnitude greater than the Ra-226 concentrations. The concentrations of Rn-222 range from 190 to 7.490 pCi/1 with an average of 2,522 pCil/l. and those of Ra-226 average 0.32 pCi/1 with the range from 0.25 to 0.42 pCi/1. The concentrations of Rn-222 and Ra-226 are inversely correlated with EC and alkalinity. The pH it positively correlated with Ra-226. The correlation between Rn-222 and Ra-226 is poor. Thermal waters in the study area are produced from highly fractured phyllite. The thermal water qualify. CSAMT (controled-source audiofrequency magnetotelluric) prospecting, and petrological evidences, however, indicate that the heat is possibly transmitted through deep normal faults reaching a deep granite batholith, and the phyllite acts only as a groundwater pathway.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1197-1204
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• 2012

As an effort to develop functional food ingredients and to discover the biological activity, the total phenolic content, total flavonoid content, DPPH and ABTS radical scavenging activity, SOD-like activity, ferric reducing antioxidant power (FRAP), and $Fe^{2+}$ chelating of Aster scaber were measured using a 70% ethanol extract and various solvent fractions. As a result, the total phenolic concent was highest in an ethyl acetate fraction of 141.9 mg GAE eq/g and the total flavonoid content was 105.6 mg QUE eq/g. The DPPH radical scavenging activity was highest in an ethyl acetate fraction of 97.1% at a concentration of 1,000 ${\mu}g/mL$ (p<0.05). The ABTS radical scavenging activity showed a 86.9% ethyl acetate fraction and a 57.9% butanol fraction at a concentration of 125 ${\mu}g/mL$, and higher than that of positive control (${\alpha}$-tocopherol and BHT) (p<0.05). The SOD-like activity showed 42.8% in an ethyl acetate at a concentration of 1,000 ${\mu}g/mL$. The ethyl acetate fraction showed the highest value of FRAP at 1051.9 ${\mu}M$ and a concentration of 1,000 ${\mu}g/mL$ (p<0.05). The $Fe^{2+}$chelating was highest in the 70.1% chloroform fraction at a concentration of 500 ${\mu}g/mL$ (p<0.05). There is the highest correlation between DPPH radical scavenging activity and FRAP (r=0.981) as compared to other antioxidant assays (p<0.01). With these results, we confirmed that the ethyl acetate fraction of Aster scaber has great antioxidant potential. So it can be expected to be developed into a specific functional food ingredient.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.609-615
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• 1996

To study the effects of the fructooligosaccharide (FOS) intake on the intestinal microflora, the FOS (8g) was served to each of 5 volunteers (adult men $23{\sim}28$ years old) after every lunch for 4 weeks. Changes in fecal microflora, fecal moisture, and fecal pH were observed during the FOS intake and after the FOS intake, respectively. The fecal moisture content of the control period (4 weeks before the intake of FOS) was $81.77{\pm}1.18%$. The moisture content of the feces increased significantly at the end of the 4th week of FOS intake, and these effects lasted for 3 weeks after stopping FOS intake. The fecal pH before FOS intake was $6.56{\pm}0.09%$, while it decreased significantly (p<0.01) during the period of FOS intake. The pH reduction lasted for 4 weeks after stopping the intake of FOS. The log fecal number of Bifidobacteria during the period was $7.88{\pm}1.43%$ (CFU/g of wet feces) and it increased significantly during the FOS intake. After stopping the intake of FOS, the number of Bifidobacteria returned to those of control period. The log fecal number of Lactobacilli before the intake was $6.76{\pm}1.34%$ and significantly increased in 3 weeks due to the FOS intake. After stopping the intake of FOS, however, the number of Lactobacilli returned to those of control period. No remarkable changes were observed in the number of coliforms throughout all durations.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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• pp.113-117
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• 2016

Recently, hydrogen is regarded as important energy in the future, because it is clean and renewable. The photoelectrochemical (PEC) system, which produce hydrogen using water splitting by solar energy, is one of the most promising energy systems because it has abundant energy sources and good theoretical efficiency. GaN has recently been regarded as suitable photoelectrode that could be used to split water to generate hydrogen without extra bias because its band edge position include water redox potential ($V_{redox}=1.23$ vs. SHE). GaN also shows considerable corrosion resistance in aqueous solutions and it is possible to control its properties, such as structure, band gap, and catalyst characteristics, in order to improve solar energy conversion efficiency. But, even if the band edge position of GaN make PEC reaction facilitate without bias, the overpotential of oxygen evolution reaction could reduce the efficiency of system. One of the ways to decrease overpotential is introduction of co-catalyst on photoelectrode. In this paper, we will investigate the effect of manganese dioxide ($MnO_2$) as a co-catalyst. $MnO_2$ particles were dispersed on GaN photoelectrode by spincoater and analyzed properties of the PEC system using potentiostat (PARSTAT4000). After coating $MnO_2$, the flat-band potential ($V_{fb}$) and the onset voltage ($V_{onset}$) were moved negatively by 0.195 V and 0.116 V, respectively. The photocurrent density increased on $MnO_2$ coated sample and time dependence was also improved. These results showed $MnO_2$ has an effect as a co-catalyst and it would enhance the efficiency of overall PEC system.