• Clean Technology
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• v.19 no.3
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• pp.257-263
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• 2013

The zinc phosphate-coated mica (ZP/mica) pigments were prepared using phosphoric acid, zinc nitrate and mica as starting materials, and used as anticorrosive pigments. The scanning electron microscopy (SEM) and x-ray diffraction (XRD) techniques were used to observe the morphology and crystal structure of prepared pigments. The prepared pigments were incorporated into an epoxy binder to prepare coating and the corrosion inhibition performance of the pigments was evaluated using electrochemical impedance spectroscopy (EIS). It was found that the anticorrosive performance of the ZP/mica pigment prepared at $70^{\circ}C$ was the better than that prepared at $20^{\circ}C$. The formation of ZnO, in addition to $Zn_3(PO_4)_2{\cdot}2H_2O$, was observed on ZP/mica pigment prepared at $70^{\circ}C$. The excellent anticorrosive performance of ZP/mica pigment could be ascribed to the synergistic effect with electrochemical anticorrosive mechanism from zinc compounds on mica and barrier anticorrosive mechanism from lamellar mica.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.112-118
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• 1979

This experiment was carried out to evaluate the effect of potassium application level for pasture management in Chungnam area. The results obtained were as follows. 1. The seedling establishment of pasture species was slightly depressed by high potassium application. 2. By increasing potassium application level, the winter hardiness of pasture species increased. 3. The forage yield of pasture species was more increased in legume single seeding than grass single and mixed seeding by higher potassium application. 4. The $K_2O$ content in forage was increased markedly by increasing potassium application level on grass single block. 5. The results obtained from this experiment indicated that potassium application level much effective on the winter hardiness of pasture species and forage yield specially in legume single seeding and adequate amount of potassium would be 20kg per 10a in this area.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.126-132
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• 1981

Rice grains harvested from paddy fields around industrial areas of Kyongin, Iri, and Jeonju were taken and analysed the contents of heavy metals which were considered to be accumulated in those rice grains. Atomic absorption spectrophotometer was applied for analysis of heavy metals such as copper(Cu), zinc(Zn), lead(Pb) and cadmium (Cd) in unpolished rice grains. The content of Cu in rice grains harvested from Iri was the lowest, 2.94 ppm, while those from Seo-Myon, Shiheung-Gun was the highest, 3.65 ppm. The contents of Zn and Pb in rice grains were ranged 20.56~27.21 ppm and 0.38~0.53 ppm, respectively. Cd content were exceptionally lower than the regulated level, 1.0 ppm. The content of this metal detected in rice grains from Seo-Myon was the highest, 0.509 ppm, but those of other areas were much lower, ranged 0.040~0.136 ppm. The present concentrations of Cu, Zn, and Pb in rice grains were also lower than the expected level and below the maximum permissible concentrations.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.118-128
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• 1989

This experiment was conducted to study the relation between the equilibrium moisture contents and the hygroscopic components in the various tobacco matters such as NC-82, Br-21, R.T.S., and puffed stem. The order of the high equilibrium moisture contents was the puffed stem, R.T.S., NC-82, and Br-21. The H-1 grades of NC-82 and Br-21 contained high contents of total sugar had higher equilibrium moisture contents than others. The moisture contents in NC-82 and Br-21 were increased at higher temperature, $30^{\circ}C$ than $20^{\circ}C$. The grades with high amounts of water extracts and total sugar affected to increase the equilibrium moisture contents in NC-82 and Br-21. In conclusion, the equilibrium contents were related to the structure of tobacco matter, the grades, the temperature, and the amount of some chemical components such as water extracts and total sugar of the leaf tobacco.

• Corrosion Science and Technology
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• v.6 no.6
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• pp.275-281
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• 2007

The effect of annealing on the pitting corrosion resistance of anodized Al-Mg alloy (AA5052) processed by equal-channel angular pressing (ECAP) was investigated by electrochemical techniques in a solution containing 0.2 mol/L of $AlCl_3$ and also by surface analysis. The Al-Mg alloy was annealed at a fixed temperature between 473 and 573 K for 120 min in air after ECAP. Anodizing was conducted for 40 min at $100-400A/m^2$ at 293 K in a solution containing 1.53 mol/L of $H_2SO_4$ and 0.0185 mol/L of $Al_2(SO_4)_3$. The internal stress generated in anodic oxide films during anodization was measured with a strain gauge to clarify the effect of ECAP on the pitting corrosion resistance of anodized Al-Mg alloy. The time required to initiate the pitting corrosion of anodized Al-Mg alloy was shorter in samples subjected to ECAP, indicating that ECAP decreased the pitting corrosion resistance. However, the pitting corrosion resistance was greatly improved by annealing after ECAP. The time required to initiate pitting corrosion increased with increasing annealing temperature. The strain gauge attached to Al-Mg alloy revealed that the internal stress present in the anodic oxide films was compressive stress, and that the stress was larger with ECAP than without. The compressive internal stress gradually decreased with increasing annealing temperature. Scanning electron microscopy showed that cracks occurred in the anodic oxide film on Al-Mg alloy during initial corrosion and that the cracks were larger with ECAP than without. The ECAP process of severe plastic deformation produces large internal stresses in the Al-Mg alloy; the stresses remain in the anodic oxide films, increasingthe likelihood of cracks. It is assumed that the pitting corrosion is promoted by these cracks as a result of the higher internal stress resulting from ECAP. The improvement in the pitting corrosion resistance of anodized AlMg alloy as a result of annealing appears to be attributable to a decrease in the internal stresses in anodic oxide films

• Journal of fish pathology
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• v.9 no.1
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• pp.65-77
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• 1996

Tachyplesin I is an antimicrobial peptide isolated from horseshoe crab. To investigate the mechanism of action of tachyplesin I for phospholipid bilayers, tachyplesin I and five analogs have been synthesized by the solution method. The synthesized five analogs are [$Phe^2$]-tachyplesin I, [$Phe^{8,13}$]-tachyplesin I, [$Cys(Acm)^{3,7,12,16}$]-tachyplesin I with no disulfide bonds, 7(Acm) and 10 (Acm) which denote the fragments [$Cys(Acm)^{3,7,12,16}$]-tachyplesin I. Circular dichroism spectra showed that tachyplesin I took an antiparallel $\beta$-structure in buffer solution and a less ordered structure in acidic liposomes. The carboxyfluorescein leakage experiment indicated that tachyplesin I interacted strongly with neutral and acidic phospholipid bilayers. In fluorescence experiment, the hydrophobic part of the peptide was shown to be embedded in lipid bilayers. All the peptides except for 7(Acm) and 10(Acm) were almost equally active in lipopolysaccharide binding. Therefore, the present study suggested that phospholipid bilayers induced a conformational change of tachyplesin I from the stable $\beta$-structure to a less ordered one.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1378-1385
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• 1999

The antioxidative activity of Fermented Anchovy on linoleic acid autooxidation was investigated in an aqueous system at pH 7.0. All solvent fractions from Fermented Anchovy were exhibited the strong antioxidative activity. Especially, BuOH and aqueous fractions were gained large amounts with strong antioxidative activity. Ultrafiltration, dialysis, heat treatment of aqueous fraction indicated that water-soluble antioxidants of Fermented Anchovy were heat-resistant, amino acid related compounds with smaller molecular weights than 1,000. Unbound fractions from DE-52 anion exchange chromatography were exhibited antioxidative activity with or without $15\;{\mu}M\;Fe^{+++}\;ion$. We were able to purify one methionine derivative from lots of antioxidative substances in Fermented Anchovy aqueous fraction by gel filtration, anion-exchange chromatography, TLC and HPLC, successfully. These data suggest that Fermented Anchovy aqueous fraction is a mixture of fermented small molecules with strong antioxidative activities.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.1
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• pp.18-25
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• 2008

The membrane electrode assembly(MEA) was prepared by a nonequilibrium impregnation- reduction (I-R) method. Nafion 117 and covalently cross-linked sulfonated polyetherether with tungsto- phosphoric acid (CL-SPEEK/TPA30) prepared by our laboratory, were chosen as polymer electrolyte membrane(PEM). $Pt(NH_3)_4Cl_2$, $RuCl_3$ and reducing agent $(NaBH_4)$ were used as electrocatalytic materials. Electrochemical activity surface area(ESA) and specific surface area(SSA) of Pt cathodic electrode with Nafion 117 were $22.48m^2/g$ and $23.50m^2/g$ respectively under the condition of 0.8 M $NaBH_4$. But Pt electrode prepared by CL-SPEEK/TPA30 membrane exhibited higher ESA $23.46m^2/g$ than that of Nafion 117. In case of Pt-Ru anodic electrode, the higher concentration of Ru was, the lower potential of oxygen reduction and region of hydrogen desorption was, and Pt-Ru electrode using 10 mM $RuCl_3$ showed best properties of SSA $34.09m^2/g$ with Nafion 117. In water electrolysis performance, the cell voltage of Pt/PEM/Pt-Ru MEA with Nafion 117 showed cell property of 1.75 V at $1A/cm^2$ and $80{\circ}C$. On the same condition, the cell voltage with CL-SPEEK/TPA30 was the best of 1.73 V at $1A/cm^2$.

• Journal of Environmental Health Sciences
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• v.32 no.4 s.91
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• pp.342-352
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• 2006

The experiments was undertaken to evaluate the effects of herbal medicine, Dalsaengtang, in pregnant rats and fetuses. Female Sprague-Dawley rats were orally administered with the Dalsaengtang at dose of 5 mg/kg/day for 20 days. Pregnant rats were sacrificed at 20th day of gestation, and observed internal and reproductive organs. Approximately live fetuses in the 20th day of gestation were randomly selected and fixed in 95% ethanol. To observe skeletal malformations, fetuses were stained with alcian blue and alizarin red S. Maternal body weight of dalsaengtang treated group has a tendency to increase compared to that of control group. The relative liver and kidney weights of dalsaengtang treated group were also increased to that of control group. There were no significant changes between two groups in blood chemistry and hematological values. There were no significant changes in number of corpus luteum, implantation, live fetuses and implantation rate, delivery rate, late resorption rate and sex ratio. But Dalsaengtang administered group showed lower early resorption rate than the control group. From the sex ratio, number of females, bigger than number of males in the control group, and more males than females in Dalsaengtang administered group. Neonatal body weight and number of fetus of Dalsaengtang group were increased to that of control group. The fetuses of dams treated with Dalsaengtang didn't showed external malformation. Vertebral and sternal variations were observed in Dalsaengtang group but, compared to the control, those variations were insignificant. The number of ribs, cervical, thoracic, and lumber were normal. The number of sacral and caudal vertebrae were increased. Fetuses showed significant difference in the number of caudal vertebra (P<0.01). From these results, it can be concluded that Dalsaengtang showed no toxicity effects on maternal body weight, early resorption rate, and number of live fetuses. There were no significant changes in organ weight, hematological data, reproductive organs. Although skeletal variations were showed in vertebrate and sternum, Dalsaengtang did not shown significant changes in bone malformation.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.157-157
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• 2003

To evaluate an effect of pathological liver damage on the cyclohexane metabolism, rats were pretreated with 50% $CCl_4$ dissolved in olive oil (0.1$\mell$/100g body weight) 10 or 17 times intraperitoneally at intervals of every other day. On the basis of liver function and histological findings, the animals pretreated with $CCl_4$ 10 times were identified as acutely liver damaged ones and the animals pretreated with $CCl_4$ 17 times were identified as severly liver damaged ones, with fibrosis, biliary abnormality and mild injury both in the kidneys and the lungs. To these liver damaged animals, cyclohexane (a single dose of 1.56g/kg body weight, i.p.) was administrated at 48 hours after the last injection of $CCl_4$. The rats were sacrificed at 4 or 8 hours after injection of cyclohexane. The cyclohexane metabolites; cyclohexanol (CH-ol), cyclohexane-1, 2-diol (CH-1, 2-diol), cyclohexane-l, 4-diol (CH-1, 4-diol), and their glucuronyl conjugates and cyclohexanone (CH-one) were detected in the urine of cyclohexane treated rats. After cyclohexane treatment, the serum levels of CH-ol and CH-one were remarkably increased at 4 hours and then decreased at 8 hours in normal group. Whereas in liver damaged rats, these cyclohexane metabolites were higher at 8 hours than at 4 hours. The excretion rate of cyclohexane metabolites from serum into urine was more decreased in liver damaged animals than normal group, with the levels of excretion rate being lower in $CCl_4$ 17 times injected animals than 10 times injected ones. However, it was interesting that the urinary concentration of cyclohexane metabolites was generally more increased in liver damaged animals than normal ones, and the increasing rate was higher in $CCl_4$ 17 times injected rats than 10 times injected ones. And liver damaged rats, especially $CCl_4$ 17 times treated ones, had an enhanced ability of glucuronyl conjugation to cyclohexanol analogues compared with normal group. Futhermore, CH-1, 2 and 1, 4-diol were all conjugated with glucuronic acid in $CCl_4$ 17 times injected animals. In conclusion, the metabolic rate of cyclohexane was unexpectably accelerated and it may be caused by physiological adaptation of adjacent intact hepatocyte in damaged liver.