• Journal of Korean Society of Water and Wastewater
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• v.13 no.2
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• pp.47-54
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• 1999

SRB(Sulfate Reducing Bacteria) converts sulfate into sulfide using an organic carbon source as the electron donor. The sulfide formed precipitates the various metals present in the AMD (Acid Mine Drainage). This study is the fundamental research on heavy metal removal from AMD using SRB. Two completely mixed anaerobic reactors were operated for cultivation of SRB at the temperature of $30^{\circ}C$ and anaerobic batch reactors were used to evaluate the effects of carbon source, COD/sulfate($SO_4^=$) ratio and alkalinity on sulfate reduction rate and heavy metal removal efficiency. AMD used in this study was characterized by low pH 3.0 and 1000mg/l of sulfate and dissolved high concentration of heavy metals such as iron, cadmium, copper, zinc and lead. It was found that glucose was an organic carbon source better than acetate as the electron donor of SRB for sulfate reduction in AMD. Amount of sulfate reduction maximized at the COD(glucose)/sulfate ratio of 0.5 in the influent and then removal efficiencies of heavy metals were 97.5% of Cu, 100% of Pb, 100% of Cr, 49% of Mn, 98% of Zn, 100% Cd and 92.4% of Fe. Although sulfate reduction results in an increase in the alkalinity of the reactor, alkalinity of 1000mg/1 (as $CaCo_3$) should be should be added continuously to the anaerobic reactor in order to remove heavy metals from AMD.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.3
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• pp.88-97
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• 2011

We carried out cationization of Dak pulp (paper mulberry bast fiber pulp) which is raw material of Hanji (Traditional Korean Paper) using a (3-chloro-2-hydroxypropyl) trimethyl ammonium chloride to improve dyeability during a dyeing of Hanji with Gardenia (Gardenia jasminoides) and smoke tree (Cotinus coggygria). Fiber specific charge densities were determined using polyelectrolyte titration method and K/S values of dyed Hanji was calculated by Kubelka-Munk equation. As the result, fiber specific charge density increased with degree of cationization. Colors of Hanji dyed with Gardenia did not vary significantly with degree of cationization, but cationized Hanji dyed with smoke tree showed a large increase of a* value and reddish yellow color. After-mordanting did not decrease K/S value of dyes with cationized Hanji. K/S values of dyed Hanji decreased with increasing dyeing temperature. For smoke tree, the cationization impair lightfastness of dyed Hanji without mordant. After-mordanting with copper acetate or iron chloride improved lightfastness of dyed Hanji.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.31-35
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• 2011

Photovoltaic modules are well known to be one of the most eco generation of electricity. But usually study solar cell. Otherwise, PV modules are also important in power generation. We have to check other subsidiary materials. In this work benefit of using optically superior encapsulation materials(EVA) in generation temperature is demonstrated. Optical characterization of three EVA products demonstrates reduced transmission in the visible ray region of the solar spectrum. It will have a decisive effect to the module efficiency. Test is shown reduction of reflectance and transmittance. Reflections is dependent on the low iron glass. It can be seen between a specific wave length(240~350mm) about 1%. Transmittance in the entire ray region of light is markedly reduced to depending on the temperature rise. The graph is shown optical properties on EVA. Transmission was reduced. about 1%.

• Bulletin of the Korean Chemical Society
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• v.21 no.12
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• pp.1193-1198
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• 2000

The preparation of nanocrystalline hematite, ${\alpha}-Fe_2O_3$, paricles and their surface coating with silica layers are described. The hematite particles with the size of 30~60 nm are firstly prepared by thermal decomposition of trinuclear acetate-hydroxo iron (III) nitrate complex, $[Fe_3$(OCOCH_3)_7$OH${\cdot}$2H_2O]NO_3$, at $400^{\circ}C$. Subsequently the hematite surfaces are coated with siliva layers by a controlled hydrolysis and condensation reaction of TEOS with varying the TEOS concentration and pH. Monodispersed and spherical $SiO_2-coatedFe_2O_3$ particles with the average particle diameter of ~90 nm and extremely narrow size distribution can be obtained at the pH of 11 and the TEOS concentration of 0.68M, which are found to be the optimum conditions in the present study in achieving the homogeneous deposition of silica layers on hematite surfaces. Diffuse reflectance UV-Vis spectra reveal that the characteristic optical reflectance of ${\alpha}-Fe_2O_3$ particles is preserved almost constant even after coating the surfaces, suggesting that the $SiO_2$ layers can be regarded as protecting layers without degrading the optical properties of hematite particles.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.148-157
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• 2019

An optimized analytical method for sodium iron chloriphyllin in foods was established and verified by using high performance liquid chromatography with attached diode array detection. An Inertsil ODS-2 column and methanol-water (80:20 containing 1% acetate) as a mobile phase were employed. The limit of detection and quantitation of sodium iron chloriphyllin were 0.1 and 0.3 mg/kg, respectively, and the linearity of calibration curve was excellent ($R^2=0.9999$). The accuracy and precision were 93.9~104.95% and 2.0~7.7% in both inter-day and intra-day tests. Recoveries for candy and salad dressing were ranged between 93 and 104% (relative standard deviation, (RSD) 0.3~4.3%), and between 83 and 115% (RSD 1.2~2.0%), respectively. Liquid chromatography mass spectrometry was used to verify the main components of sodium iron chlorophyllin which were Fe-isochlorin e4 and Fe-chlorin e4.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.3
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• pp.249-254
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• 1995

The effects of bentonite (B) on rumen protozoal population and rumen fluid characteristics of sheep fed palm kernel cake (PKC) were studied for a period of 21 days. Two groups, each comprising two sheep were fed either PKC or PKC + B ad libitum A third group was left at pasture. Rumen fluid was sampled through a rumen cannula three times daily from all animals. Palm kernel cake contained 16% crude protein, 1 % crude fat and high amounts of copper, zinc, iron and manganese. Protozoal population in the rumen fluid decreased significantly (p < 0.05) after the onset of feeding PKC or PKC + B. However, sheep given bentonite supplementation at 2% of the dietary dry matter, maintained higher protozoal densities ($15{\times}10^4/ml$) when compared to animals fed only PKC ($8{\times}10^4/ml$). With both diets, the protozoa were mainly of the small entodinia species. Animals at pasture had higher protozoal population ($47{\times}10^4/ml$) with varying species of entodiniomorphids and holotrichs. Rumen fluid pH and ammonia concentration was significantly (p < 0.05) higher in animals at pasture compared to animals fed PKC or PKC + B. Volatile fatty acid concentration was significantly (p < 0.05) lower in animals fed PKC when compared to animals at pasture. There was a shift in fermentation pattern in animals fed PKC or PKC + B towards a lower acetate; and higher propionate, isovalerate and valerate. Studies in vitro also showed the positive effect of bentonite on protozoal numbers.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.225-231
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• 2008

Oxidative stress plays a crucial role in the laying stage which is a critical period for chick survival. We investigated the relationship of neonatal chick performance, brain antioxidant status and vitamin E supplementation level in hens. Starting at 17 weeks, hens were randomly divided into five groups. The control group received a basal diet without supplemental vitamin E (VE, dl-${\alpha}$-tocopherol acetate). Other groups received the same basal diet supplemented with vitamin E (40, 80, 120 and 160 mg/kg) through growth to egg production. Hens were artificially inseminated at 28 weeks of age and egg yolks were collected at day two. All remaining eggs were hatched. Yolk vitamin E content, hatchability and fertility of eggs were evaluated. Brains of the newly hatched chicks were further evaluated for their oxidative stress status, antioxidative status and vitamin E levels. Increased reproductive performance was observed in fertility and hatchability in the group supplemented at 40 mg/kg. Egg yolk and neonatal brain ${\alpha}$-tocopherol was highest in eggs from hens fed 120 mg/kg and 80 mg/kg supplemental vitamin E, respectively. Brain MDA, ROS and iron levels were significantly higher in unsupplemented hens (p<0.01). SOD activity was significantly higher in the group supplemented at 160 mg/kg than in all other groups. We concluded that maternal supplementation of vitamin E had beneficial effects on fertility, hatchability of eggs, neonatal brain oxidative status and SOD activity.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.406-413
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• 2009

This study was carried out to investigate the natural dyeing characteristics of Korean traditional hand-made paper (Hanji). The Hanji was dyed black with extractive of gallnut (Rbusjavanica L), leaves of Amur maple (Acer ginnala), nutshell of chestnut (Castania crenata), and persimmon juice and Chinese ink. And moreover, the Hanji was dyed not only using single and combination of dyestuff but also changing mordants and mordanting procedure. And we estimated the relationship between dyeing characteristics and dyestuff concentration (o.w.f.). The gallnut was the most principal material dyeing black. The procedure of mordanting from copper acetate to Iron (II) chloride and dyeing from gallnut to Amur maple dyestuffs were the best dyeing method for the Hanji to black. The K/S value of dyed Hanji increased with increasing concentration of dyestuff.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.654-660
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• 1998

$[Fe^{II}Fe^{III}BPLMP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)amino) methyl]-4-methylphenol (HBPLMP). Complex I has been characterized by X-ray diffraction method as having (μ-phenoxo)bis(acetato)diiron core. Complex 1 was crystallized in the monoclinic space group C2/c with the following cell parameters: a=41.620(6) Å, b=14.020(3) Å, c=27.007(4) Å, β=90.60(2)°, and Z=8. The iron centers in the complex 1 are ordered as indicated by the difference in the Fe-O bond lengths which match well with typical $Fe^{III}-O\; and\; Fe^{II}-O$ bond lengths. Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electochemical methods. Complex 1 exhibits strong bands at 592 nm, 1380 nm in $CH_3CN$ (ε = 1.0 × 103 , 3.0 × 102). These are assigned to $phenolate-to-Fe^{III}$ and intervalence charge-transfer transitions, respectively. Its NMR spectrum exhibits sharp isotropically shifted resonances, which number half of those expected for a valence-trapped species, indicating that electron transfer between $Fe^{II}\;and\;Fe^{III}$ centers is faster than NMR time scale. This complex undergoes quasireversible one-electron redox processes. The $Fe^{III}_2/Fe^{II}Fe^{III}\;and\;Fe^{II}Fe^{III}/Fe^{II}_2$ redox couples are at 0.655 and -0.085 V vs SCE, respectively. It has $K_{comp}=3.3{\times}10^{12}$ representing that BPLMP/bis(acetate) ligand combination stabilizes a mixed-valence $Fe^{II}Fe^{III}$ complex in the air. Complex 1 exhibits a broad EPR signal centered near g=1.55 which is a characteristic feature of the antiferromagnetically coupled high-spin $Fe^{II}Fe^{III}$ system $(S_{total}=1/2)$. This is consistent with the magnetic susceptibility study showing the weak antiferromagnetic coupling $(J= - 4.6\;cm^{-1},\; H= - 2JS_1{\cdot}S2)$ between $Fe^{II}\; and \;Fe^{III}$center.

• Journal of Soil and Groundwater Environment
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• v.12 no.5
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• pp.105-114
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• 2007

The most advanced oxidation processes (AOPs) are based on reactivity of strong and non-selective oxidants such as hydroxyl radical (${\cdot}OH$). Decomposition of typical DNAPL chlorinated compounds (TCE, PCE) using various advanced oxidation processes ($UV/Fe^{3+}$-chelating agent/$H_2O_2$ process, $UV/H_2O_2$ process) was approached to develop appropriate methods treating chlorinated compound (TCE, PCE) for further field application. $UV/H_2O_2$ oxidation system was most efficient for degrading TCE and PCE at neutral pH and the system could remove 99.92% of TCE after 150 min reaction time at pH 6($[H_2O_2]$ = 147 mM, UVdose = 17.4 kwh/L) and degrade 99.99% of PCE within 120 min ($[H_2O_2]$ = 29.4 mM, UVdose = 52.2 kwh/L). Whereas, $UV/Fe^{3+}$-chelating agent/$H_2O_2$ system removed TCE and PCE ca. > 90% (UVdose = 34.8 kwh/L, $[Fe^{3+}]$ = 0.1 mM, [Oxalate] = 0.6 mM, $[H_2O_2]$ = 147 mM) and 98% after 6hrs (UVdose = 17.4 kwh/L, $[Fe^{3+}]$ = 0.1 mM, [Oxalate] = 0.6 mM, $[H_2O_2]$ = 29.4 mM), respectively. We improved the reproduction system with addition of UV light to modified Fenton reaction by increasing reduction rate of $Fe^{3+}$ to $Fe^{2+}$. We expect that the system save the treatment time and improve the removal efficiencies. Moreover, we expect the activity of low molecular organic compounds such as acetate or oxalate be effective for maintaining pH condition as neutral. This oxidation system could be an economical, environmental friendly, and practical treatment process since the organic compounds and iron minerals exist in nature soil conditions.