• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.4
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• pp.37-49
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• 2001

This study was performed in order to produce the basic data for developing prediction techniques of desalinization to be applicable to reclaimed tidal lands at the beginning stage. the desalinization experiments were carried out by two water management practices, namely, the leaching method by subsurface drainage and the rinsing method by surface drainage. The 5 soil samples used in this study were collected in 4 tidal land reclamation projects. Regression equations were obtained in order to investigate the changes of electrical conductivity during the desalinization of reclaimed tidal lands and to estimate water requirements for desalinization. The results obtained from this study were summarized as follows: 1. According to USDA Salinity Laboratory classification system of salt affected soils the reclaimed tidal land soils used in this study were saline-sodic soils with the high electrical conductivity and the high exchangeable sodium percentage. 2. With the increase of the water requirements for desalinization the electrical conductivity was decreased with high degree of correlationships and the desalinization effects were remakable in both the leaching method and the rinsing method. 3. In case of the leaching method the electrical conductivity had been reduced below the classification value of salt affected soils when the depth o water leached per unit depth of soil (Dwl/Ds) was 0.3 and the desalinization effects showed a tendency to be much the same in each treatment.

• Korean Journal of Medicinal Crop Science
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• v.24 no.5
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• pp.351-359
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• 2016

Background: We investigated the optimal aqueous extraction conditions for recovery of high yields of total phenolic compounds from roots of Arctium lappa L. (burdock, Asteraceae), and we compared their antioxidant capacity. Methods and Results: The antioxidant activity of the extracts was tested using 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt, and oxygen radical absorbance capacity assays. In addition, the major phenolic compounds present in the extracts were determined by high performance liquid chromatography analysis. Our results suggest that the roasted burdock $100^{\circ}C$, 15 min extract exhibited the strongest radical scavenging activity and possessed the highest concentration of phenolic compounds. The polyphenol content of both dried burdock and roasted burdock significantly increased with increase in the extraction temperature and time. Conclusions: These results indicated a relationship between phenolic compound levels in burdock and their free radical scavenging activities. This suggests that phenolic compounds significantly increase the antioxidant potential of burdock extracts.

• Textile Coloration and Finishing
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• v.26 no.1
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• pp.32-38
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• 2014

There has been increasing demand to the eco-friendly materials such as phytoncide which is extracted to plants in the textile industry, recently. It is interesting that alginic acid sodium salt(Alg-Na) is used to eco-friendly binder for the functional capsule finishing. In this study, we made PEO/Alg-Na blend solutions of various ratio and observed the changing binding property of the blend solutions according to PEO contents through FT-IR, DSC, contact angle, peel strength, etc. The viscosity of Alg-Na/PEO blend solutions increased with increase of contents and the viscosity quickly increased with increase of PEO content in Alg-Na 5% content, specially. It is shown that the hydrogen bond peak by blend of Alg-Na and PEO found through FT-IR analysis but the peak decreased in PEO above 60% content. And the peel strength was predominant in PEO 50% ratio.

• Solar Energy
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• v.10 no.2
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• pp.77-85
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• 1990

In the present analysis, a number of sun control devices are examined for their performance in promoting the interior visual environment. Two exemplary cases are introduced for their excellence in harnessing the concept of daylighting and passive concepts. Of these, the Johnson Controls branch office building in Salt Lake City manifests the effectiveness of light shelves and clerestory windows in implementing these concepts. Distinct optical characteristics are found for overhangs, light shelves, louvers, and blinds as they interfere with the path of sunlight. Substantial amount of energy could be saved if the fundamentals of these devices are truly understood in their application to residential and commercial buildings. Sustained efforts should be made in this regard by the builders, architects, energy consultants, and educators who make contributions in energy management.

• Journal of Powder Materials
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• v.11 no.2
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• pp.143-148
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• 2004

In the present study, $TiO_2$ imbedded composite powders have been successfully prepared from the (Cu. Zn)/$TiO_2$ composite salt solution. The composite (Cu, Zn)/$TiO_2$ powders were formed by drying the solution at 200~$600^{\circ}C$ in the hydrogen atmosphere. Photocatalytic characteristics was evaluated by detecting the decomposition ratio of aniline blue with UV-visible spectrophotometer(Shimazu Co., UV-1601). Phase analysis of (Cu, Zn)/$TiO_2$ composite powders was carried out by XRD and DSC, and powder size was measured with TEM. The mean particle size of composite powders was about 100mm. As the reduction temperature increases, a few zinc sulfide and oxide phases was formed and copper oxide phase was reduced. The decomposition ratio of aniline blue was about 80％ under the UV irradiation by the TiO$_2$ phase in the composite (Cu, Zn)/$TiO_2$ powders and similar decomposition ratio of 80％ was obtained at the UV lightless condition by virtue of Cu and Zn compounds.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1117-1120
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• 2014

Ru/C-catalyzed hydrogenation of m-xylylene diamine into 1,3-cyclohexanebis(methylamine) was greatly accelerated by the presence of $LiNO_3$, $NaNO_2$, or $NaNO_3$. It was found that the effect of the nitrate salt was significantly affected by the size of cation. The promoting effect of the nitrate salt increased with the decrease of the cation size: $LiNO_3$ ~ $NaNO_2$ > $KNO_3$ > $CsNO_3$ >> [1-butyl-3-methylimidazolium]$NO_3$. XRD analysis of the recovered catalysts after the hydrogenation reactions showed that $LiNO_3$ and $NaNO_2$ were completely transformed into LiOH and NaOH, respectively, along with the evolution of $NH_3$, while $KNO_3$ and $CsNO_3$ remained unchanged.

• Membrane and Water Treatment
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• v.3 no.4
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• pp.253-266
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• 2012

In this work, the effect of hybrid salts precipitation-nanofiltration (SP-NF) process on the scale deposits in thermal and membrane desalination processes has been studied. The analysis was carried out to study the scale formation from the Arabian Gulf seawater in MSF and RO reference processes by changing the percentage of pretreatment from 0 to 100%. Four different SP-NF configurations were suggested. A targeted Top Brine Temperature (TBT) of $130^{\circ}C$ may be achieved if 30% portion is pretreated by SP and/or NF processes. As a rule of thumb, each 1% pretreatment portion increases the reference TBT of $115^{\circ}C$ by $0.6^{\circ}C$. For both MSF and RO, parallel pretreatment of certain percentage of the feed by SP and the rest by NF, showed the lowest scale values. The case showed the best values for sulfate scale prevention and the highest values of increasing the monovalent ions relative to the divalent scale forming ions. Sulfate scale is significant in MSF process while carbonate scale is significant in RO. Salt precipitation was suggested because it is less costly than nanofiltration, but nanofiltration was used here because it is efficient in sulfate ions removal.

• Journal of Microbiology
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• v.43 no.1
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• pp.1-10
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• 2005

We isolated and cultured bacteria inhabiting solar saltern ponds in Taean-Gun, Chungnam Province, Korea. All of the isolated 64 strains were found to be moderately halophilic bacteria, growing in a salt range of 2-20 %, with an optimal concentration of 5% salt. Bacterial diversity among the isolated halophiles was evaluated via RFLP analyses of PCR-amplified 16S rDNAs, followed by phylogenetic analysis of the partial 16S rDNA sequences. The combination of restriction enzyme digestions with HaeIII, CfoI, MspI and RsaI generated 54 distinct patterns. A neighbor-joining tree of the partial 16S rDNA sequences resulted in the division of the 64 strains into 2 major groups, 45 strains of ${\gamma}-Proteobacteria$ (70.3%) and 19 strains of Firmicutes (29.7%). The ${\alpha}-Proteobacteria$ and Cytophaga-Flavobacterium-Bacterioides groups, which were repeatedly found to exist in thalassohaline environments, were not represented in our isolates. The ${\gamma}-Proteobacteria$ group consisted of several subgroups of the Vibrionaceae (37.5%), Pseudoalteromonadaceae (10.9%), Halomonadaceae (7.8%), Alteromonadaceae (7.8%), and Idiomarinaceae (6.3%). Members of Salinivibrio costicola (29.7%) were the most predominant species among all of the isolates, followed by Halobacillus treperi (12.5%). Additionally, three new species candidates were found, based on similarities of the 16S rDNA sequences to those of previously published species.

• The Korean Journal of Ecology
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• v.11 no.1
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• pp.1-15
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• 1988

Studies on species compostion, promary production of benthic algal assemblage were carried out along a channel of the salt marsh near Inch'on, Kyonggi Bay, Korea. Possible biological, physical and KDICical factors controlling the aglal assemblage were also examined. The oveall diatoms were encountered one hundred and thirty-seven taxa, of which the dominant species were Paralia sulcata and Cymatosira belgica. These two species accounted for 32.6% relative abundance throughout the study period. Diatom taxa had no clear seasonal pattern in abundance analysis. But at the algal blooming period in spring, euglenoids occurred with a high abundance. The chlorophyll a content of benthic algae showed definite seasonal pattern. The algal biomass of the appeared to influence the spatial fluctuation in the algal biomass of the channel was regulated primarily by water content of sediment. Grazing by zoobenthos apperaed to influence the spatial fluctuation in the algal biomass of the sediment surface. The algal photosynthesis was measured in the laboratory with oxygen method. Photo-synthetic rate was independent of the temperature under the lower irradiance. The gross production from March to November was estimated to be 190g C/m2 at the channel slope. Photosynthetic efficiency was 0.37% on the basis of the photosyntherically active radiation for the study period.

• Analytical Science and Technology
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• v.16 no.3
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• pp.198-205
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• 2003

The ammonium salt of nitrosophenylhydroxylamine, called cupferron, has been used not only as the ligand but also as an oxidizing agent for adsorptive catalytic stripping voltammetry (AdCtSV). Cyclic voltammetry was used for elucidating the electrochemical behavior of Os-cupferron complex in 1 mM phosphate buffer. The optimal conditions for osmium analysis were found to be 1 mM phosphate buffer solution (pH 6.0) containing 0.1 mM cupferron at scan rate of 100 mV/s. By using the plot of reduction peak currents of linear scan voltammograms vs. osmium concentration, the detection limit was $1.0{\times}10^{-7}M$.