• Applied Microscopy
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• v.30 no.4
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• pp.357-365
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• 2000

Paneth cells have been suggested to contribute to the elimination of excess metals into the intestinal lumen. The purpose of this study wat to investigate the changes of the zinc pools in rats subjected to functional loading with zinc salt by mean of both light and electron microscopical autometallography (AMG). Wistar rats 4 were administrated with zinc chloride (20 mg/kg body weight) intraperitoneally dissolved in 1 ml distilled water. The control group received 1 ml saline IP. After further one hour the animals were transcardially perfused with 0.4% sodium sulphide dissolved in 0.1 M PB fellowed by 3% glutaraldehyde solution for 10 minutes. Pieces of ileum were frozen with solid $CO_2$ and sectioned on a cryostat. The sections $(20{\mu}m)$ were autometallographically developed. Sections selected for EM were reembedded on top of a blank Epon block, from which ultrathin sections (100 nm) were cut. The ultrathin sections were double stained with uranyl acetate (30 min) and lead citrate (5 min), then examined under electron microscope. Studies of comparable sections from control and zinc loaded animals with the AMG selenium method gave quite different results. The control animals demonstrated a weakly positive staining in the cytoplasm of the Paneth cells. In the electron microscope the AMG silver grains were found to be located in the cytoplasm, while the electron dense secretary granules and other cell organelles were void of staining. Few AMG grains were located at the apical surface of the Paneth cells. In sections from zinc loaded rats, the AMG grains were seen in abundance in the lumen of the Lieberkuhn crypts at light microscopic levels. At EM levels the zinc revealing silver grains were located in the cytoplasm as in the controls, but much more AMG grains were shifted into the secretary granules. Furthermore, profound AMG grains were found in the lumen of the crypts and surrounding vessels. And a few grains were seen in the endothelium. The AMG technique demonstrated a pattern of AMG grains in the Paneth cells that strongly suggests a transport of zinc ions through these cells.

• Journal of the Korean Chemical Society
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• v.7 no.3
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• pp.216-224
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• 1963

Reaction of organic chlorine containing ester, alcohol, and acids with metallic tin and zinc in dimethyl formamide solvent gave a good yield of organo metallic complex. The same reaction under a mixed U.V. irradiation could not give an appreciable yield of the complex except in the case of an elevated reaction temperature. The solvation effect of dimethyl formamide of the metallic complex formation was markedetly increased as compared to the reaction in toluene and cyclohexane. In case of chlorine containing carboxylic acid, the formation of organo chloro zinc complex of the salt was observed. The reaction of organo zinc complex with a carbonyl precursor gave the addition product together with a dimerized product. Especially the aldehyde species enhanced the formation of zinc complex. The addition reaction was simple and convenient, but the yield was not high.(30-40% for the acid, 73% for the ester, 14.6% for alcohol). The result was discussed on basis of solvent effect and the procedures were described.

• Journal of Ocean Engineering and Technology
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• v.24 no.5
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• pp.67-74
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• 2010

Chromate conversion coating is a coating technique used to passivate aluminum, zinc, cadmium, copper, silver, magnesium, tin, and their alloys to slow corrosion. The process uses various toxic chromium compounds, which may include hexavalent chromium. The industry is developing less toxic alternatives in order to comply with substance restriction legislation, such as RoHS. One alternative is to develop a Cr-free coating solution. In this study, eco-friendly, Cr-free solutions (urethane solution S-700, organic/inorganic solution with Si LRO-317) were used. Test specimens were dried in a drying oven at $190^{\circ}C$ for 3, 5, 7, and 9 minutes. Corrosion resistance was evaluated using a salt spray test for 72 hours. The results show that the optimum corrosion resistance was achieved at $190^{\circ}C$ for five minutes for EGI and three or five minutes for HDGI, respectively. The adhesive properties of the two types of coating solutions were superior regardless of drying time.

• Journal of Applied Biological Chemistry
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• v.56 no.4
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• pp.191-197
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• 2013

To classify the chemical hazard according to globally harmonized system of classification and labeling of chemicals (GHS), we investigated the genotoxicity of three chemicals, methyl myristate, 2-ethylhexanoic acid zinc salt, N,N,N',N'-tetrakis(2-hydroxyethyl) ethylenediamine, using male ICR mice bone marrow cells for the screening of micronucleus induction. Although these three chemicals have already been tested numerous times, a micronucleus test has not been conducted. The seven week-old male ICR mice were tested at three dosages for the three chemicals, respectively. After 24 h of oral administration with the three chemicals, the mice were sacrificed and their bone marrow cells were prepared for smearing slides. As a result of counting the micronucleated polychromatic erythrocyte (MNPCE) of 2,000 polychromatic erythrocytes, all treated groups expressed no statistically significant increase of MNPCE compared to the negative control group. There were no clinical signs related with the oral exposure of these three chemicals. It was concluded that these three chemicals did not induce micronucleus in the bone marrow cells of ICR mice, and there was no direct proportion with dosage. These results indicate that the three chemicals have no mutagenic potential under each test condition, and it is not classified these chemicals as mutagens by GHS.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.6
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• pp.1231-1244
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• 2014

Oysters, especially are excellent source of several mineral including iron, zinc and selenium, which are often low in the mordern diet. They are also an excellent source of glycogen, vitamin B12 and considered the healthiest when eaten raw on the half shell in good tasted season from November to March. This study was investigated for the purpose of obtaining basic data which can be applied to processing of two kinds of canned boiled oyster (canned boiled oyster, canned boiled oyster in bamboo salt). Shucked oyster meat was cooked in steam (15min) after washing with water, filled 90g into can (301-3), added with salt solution and then precooked for 10 min. at $100^{\circ}C$. Canned boiled oyster was added 1.5% salt solution 60mL. Canned boiled oyster in bamboo salt was added 0.5% salt solution 30mL and 0.7% bamboo salt solution 30mL. The cans were seamed using a vacuum seamer, and then sterilized for various Fo values (Fo 8~12 min.) in a steam system retort at $116^{\circ}C$, $118^{\circ}C$. Viable bacterial count, proximate composition, pH, salinity, yield, VBN, amino-N, TBA, mineral, color value, free amino acid, hardness and sensory evaluation of two kinds of canned boiled oyster produced at various sterilization condition (Fo 8~12 min.) were measured after divide to meat and juice. The results showed that canned boiled oyster in bamboo salt sterilized at Fo 8 min. was the most desirable because this condition is the most economical and tasty.

• Journal of Microbiology and Biotechnology
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• v.20 no.11
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• pp.1577-1584
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• 2010

In total, 140 halotolerant bacterial strains were isolated from both the soil of barren fields and the rhizosphere of six naturally growing halophytic plants in the vicinity of the Yellow Sea, near the city of Incheon in the Republic of Korea. All of these strains were characterized for multiple plant growth promoting traits, such as the production of indole acetic acid (IAA), nitrogen fixation, phosphorus (P) and zinc (Zn) solubilization, thiosulfate ($S_2O_3$) oxidation, the production of ammonia ($NH_3$), and the production of extracellular hydrolytic enzymes such as protease, chitinase, pectinase, cellulase, and lipase under in vitro conditions. From the original 140 strains tested, on the basis of the latter tests for plant growth promotional activity, 36 were selected for further examination. These 36 halotolerant bacterial strains were then tested for 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity. Twenty-five of these were found to be positive, and to be exhibiting significantly varying levels of activity. 16S rRNA gene sequencing analyses of the 36 halotolerant strains showed that they belong to 10 different bacterial genera: Bacillus, Brevibacterium, Planococcus, Zhihengliuella, Halomonas, Exiguobacterium, Oceanimonas, Corynebacterium, Arthrobacter, and Micrococcus. Inoculation of the 14 halotolerant bacterial strains to ameliorate salt stress (150 mM NaCl) in canola plants produced an increase in root length of between 5.2% and 47.8%, and dry weight of between 16.2% and 43%, in comparison with the uninoculated positive controls. In particular, three of the bacteria, Brevibacterium epidermidis RS15, Micrococcus yunnanensis RS222, and Bacillus aryabhattai RS341, all showed more than 40% increase in root elongation and dry weight when compared with uninoculated salt-stressed canola seedlings. These results indicate that certain halotolerant bacteria, isolated from coastal soils, have a real potential to enhance plant growth under saline stress, through the reduction of ethylene production via ACC deaminase activity.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.579-584
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• 1999

The trace mineral status of cattle in the smallholder grazing areas of Sanyati and Chinamhora in Zimbabwe was evaluated during the rainy and dry seasons of 1994 and 1995. The evaluation was done in terms of mineral concentration in blood plasma. Plasma copper in calves, steers and cows in the dry season was; Sanyati: 0.55, 0.59, and 0.61; Chinamhora: 0.59, 0.58, and $0.60{\mu}g/ml$, respectively versus a normal of $0.65{\mu}g/ml$. In the rainy season, copper was deficient at both sites (averaging $0.56{\mu}g/ml$ and $0.59{\mu}g/ml$ at Sanyati and Chinamhora, respectively). Plasma selenium in the dry season was 0.017, 0.025, and $0.017{\mu}g/ml$ for calves, steers and cows, respectively at Sanyati versus a normal of $0.03{\mu}g/ml$ and therefore considered to be deficient. Iron, zinc and cobalt were found to be generally high and therefore unlikely to be deficient. Copper and selenium are recommended in salt licks in these environments.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.13-16
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• 2005

Generally, as corrosive protection processing of a steel structure, zinc galvanizing and heavy duty coating paint are applied. However, zinc galvanizing has the difficulty of restriction of a size, or on-site construction. Moreover, heavy duty coating paint has a problem with many administrative and maintenance expenses with short problem of adhesion, corrosion generating of a damage portion, and maintenance management cycle. In this study, a salt water spray test, CASS test, and the electrochemistry examination were carried out for the thermal metal spray method of construction for corrosive protection performance evaluation. Moreover, the corrosive protection life of a thermal metal spray method of construction was quantitatively calculated on the basis of this experiment. in consideration of LCC, the economical efficiency of a general corrosive protection method of construction and a thermal metal corrosive protection method of construction was compared. Consequently, although initial construction expense was estimated 16 to $30\%$ high, as for a thermal metal spray method of construction, it turns out that the administrative and maintenance expenses for 100 years became cheap 9.3 to 13 or more times.

• Journal of the Korean institute of surface engineering
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• v.44 no.6
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• pp.239-245
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• 2011

Magnesium alloys is the lightest by structural metals, but it is not good corrosion resistant because of pit, void. Particularly, AZ31B magnesium alloy sheets that have slag, scratch by rolling process indicate some defects. The objective of this research is to perform uniform plating on AZ31B by studying etching and zincate process. Especially, zincate treatment by zinc salt and pyrophosphate is the most important in the decoration plating. Dissolution of magnesium is reduced by the formation of uniform zinc conversion layer during strick and post process, which decreases defects for plating process.

• 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.