• Journal of the Korean institute of surface engineering
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• v.45 no.5
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• pp.198-205
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• 2012

The corrosion properties of anodized films on aluminium 6070 alloy in a sulfuric acid have been studied. Comparison to evaluate the anodized A6070 and pure 6070 specimen, corrosion tests in $HNO_3$ vapor environment of the 20 wt.% were performed up to 72 hours. Characteristics of film formation and surface morphology were examined by optical microscopy, FE-SEM, and EDS. The oxide film anodized in the sulfuric acid solution contained 5 to 10 wt.% of sulfur. In the initial stages of corrosion, anodized specimens exhibited corrosion resistance than the pure specimen. However, the corrosion conditions in 24 hours, corrosion was far more anodized specimen than pure specimen. Therefore, anodized films contained sulfur, nitric acid vapor in the environment is thought to stimulate corrosion.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.734-737
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• 1998

The hexane fractions from methanolic extracts of Anetheum graveolens L. (Umbelliferae) and Acorus gramineus Soland. (Araceae) revealed potent inhibitory activities against the resistance of multi-drug resistant Staphylococcus aureus SA2 when combined with ampicillin (Am) or chloramphenicol (Cm). As active principles, carvone and the liquid mixture containing carvone from Anetheum graveolens L. and a liquid mixture mainly consisting of benzoic acid phenyl-methyl ester (benzyl benzoate) from Acorus gramineus Soland. were identified. They showed resistance inhibition at the level of 20-50${\mu}g$/ml when combined with 100 or ${\mu}g$/ml of Am or Cm, respectively.

• International Journal of Concrete Structures and Materials
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• v.3 no.2
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• pp.97-101
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• 2009

It has been known that acid-resistant concretes on the liquid glass basis have high porosity (up to 18${\sim}$20%), low strength and insufficient water resistance. Therefore they can not be used as materials for load-bearing structural elements. Significant increasing of silicate matrix strength and density was carried out by incorporation of special liquid organic alkali-soluble silicate additives, which block of superficial pores and reduces concrete shrinkage deformation. It was demonstrated that introduction of tetrafurfuryloxisilane additive sharply increases strength, durability and shock resistance of silicate polymer concrete in aggressive media. This effect is attributable to hardening of contacts between silicate binder gel globes and modification of alkaline component owing to "inoculation" of the furan radical. The optimal concrete composition with the increased strength, chemical resistance in the aggressive environments, density and crack resistance was obtained.

• The Plant Pathology Journal
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• v.15 no.6
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• pp.319-322
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• 1999

In order to obtain bacterial metabolites inducing disease resistance in pepper plant, two hundred bacterial isolates were isolated from the rhizosphere soil of tobacco, cucumber, and pepper plant. Ethyl acetate extract of each bacterial culture was used to screening for induction of resistance against phytophthora blight of pepper plant. Application of ethyl acetate extract of an isolate SH122 culture to pepper plant conferred resistance against phytophthora blight consistently and significantly. According to cellular fatty acid analysis and other characteristics, the SH122 culture were significantly lower than those on control plants treated with ethyl acetate extract of nutrient broth. The B. pumilus SH122 itself of ethyl acetate extract of its culture did not show antifungal activity against phytophthora blight in pepper plants.

• Journal of the Korean Applied Science and Technology
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• v.24 no.4
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• pp.399-409
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• 2007

Characteristics of polyaniline anti-corrosive coatings with various primer coating resins(epoxy resin, urethane resin, and others) and top coating resins(epoxy and acrylic urethane resins) were investigated through adhesion, acid resistance, alkaline resistance, water resistance, and anti-corrosion tests. As a result, the anti-corrosive properties of the prepared coatings using polyaniline varied with the types of primer and top coating resins. In this condition, the properties of adhesion, chemical resistance, and water resistance were found to be very satisfactory when using emeraldine base (EB) of polyaniline blended with single-packaged urethane and acrylic urethane resins as the primer coatings, and using acrylic urethane resin as the top coatings. Also, the anti-corrosive function of these anti-corrosive coatings was well preserved for 1000 hr in the salt spray experiment.

• Journal of the Korean institute of surface engineering
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• v.45 no.4
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• pp.162-167
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• 2012

Ni-P/C multi-layer was synthesized by electroless plating and paste coating for better corrosion and surface conductance as a metallic bipolar plate. The Ni-P layer could be synthesized with the range of 2.6~22.4 at.% P contents and it's surface morphology and corrosion resistance depend on content of P. Corrosion resistance of the Ni-P layer in sulfuric acid by electrochemical test is similar with pure Ni. Surface resistance of pure Ni after corrosion was increased about 8% compared to pure Ni. On the other hand, that of the Ni-P/C composite with 20% carbon content was increased only 1%.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.326-333
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• 2010

A total of 105 nontyphoid Salmonella isolated from infants in Seoul from 2003 to 2009 was investigated for their serotype, antimicrobial resistance, characterization of integron, and the patterns of Pulsed-field gel electrophoresis (PFGE). Eighteen serotypes were detected in 105 isolates, and the two most common serotypes were S. Enteritidis (47.6%) and Montevideo (15.2%). Among the Salmonella serovars, a high level of antimicrobial resistance was found to ampicilin (60%), tetracycline (46.7%), streptomycin (35.2%) and nalidixic acid (28.6%). In the multi-drug resistance patterns, the predominant patterns were only nalidixic acid (15.7%), ampicillin-ampicillin/sulbactam-tetracycline (14.5%), and ampicillin-streptomycin-chloramphenicol-tetracycline (10.8%). PCR and DNA sequencing analysis revealed the presence of class 1 integron in 20 isolates (19%). Of the class 1 integron positive isolates 20% harboured the integron-associated gene cassettes : aadA2, blaP1, dfr17-aadA5, dfrA12-aadA2, and aadA7. PFGE was carried out to examine the genetic relatedness among S. Enteritidis isolates. Except for three strains, fifty strains were divided by three pulsotypes.

• Journal of fish pathology
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• v.13 no.2
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• pp.111-119
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• 2000

One hundred and twenty three strains of bacterial flora collected from Kunsan bay and examined for drug resistance to 9 antibiotics. The isolated and examined bacteria were Vibrio spp.(44 strains), Pseudomonas spp.(42 strains), Aeromonas spp.(26 strains), Moraxella spp.(9 strains), Enterobacteria spp.(6 strains), Bordetella spp.(3 strains), Alkaligenesis spp.(3 strains), Staphylococcus spp.(3 strains), and Flavobacterium spp.(2 strains). The drugs used were Ampicillin(AM), Penicillin-G(PM), Rifampicin(RF), Streptomycin(SM), Oxolinic acid (OA), Nalidixic acid(NA), Oxytetracycline(OT), Amikacin(AK), and Enorfloxacin(EF). Forty two strains were found to be sensitive to all drugs. The remaining strains showed resistance to various combinations of drugs. Among the resistant strains were mostly restricted to AM(54 strains/43.9%), PM(47 strains/38.2%), RF(35 strains/28.4%), SM(9 strains), OA(5 strains/ 4.06%), and NA(1 strains/0.8%), in combination at high degree showing 15 different drug resistant patterns. The most frequently showed resistant patterns were AM-PM-RF(16 strains/13.4%), AM-PM(8 strains/6.5%), and PM-RF(7 strains/5.6%). These results suggested that Kunsan bay were contaminated with various strains of highly resistant strains to drugs(AM, PM and RF). These results suggest that high levels of various antibiotics have already been introduced to Kunsan bay. Furthermore it seems that chemotherapy of fish disease has become extremely difficult because of the acquirement of multi-drug resistance to wide range of antibiotics.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.3
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• pp.387-394
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• 2009

It has been observed that coated steel structures are rapidly deteriorated than designed lifetime due to acid rain caused by air pollution etc.. Therefore improvement of corrosion resistance of anti-corrosive paint is very important in terms of safety and economic point of view. In this study corrosion resistance for five kinds of anti-corrosive paints including acryl, fluorine and epoxy resin series were investigated with electrochemical methods such as corrosion potential, polarization curves, impedance and cyclic voltammogram measurements etc.. There were somewhat good relationships between values measured by electrochemical methods such as corrosion current density obtained by cathodic and anodic polarization curves, value of impedance estimated with AC impedance, and polarization resistance on the cyclic voltammogram, for example, corrosion current density was decreased with increasing of values of impedance and polarization resistance on the cyclic voltammogram. However their relationships between corrosion current density and corrosion potential were not well coincided each other. Consequently it is considered that although a corrosion potential of F101 of fuoric resin series shifted to negative direction than other anti-corrosive paints, its corrosion resistance, indicating on the cathodic and anodic polarization curves, AC impedance curves and cyclic voltammogram, was the most superior to other paints, whereas A100 containing arcylic resin showed a relatively poor corrosion resistance compared to other paints.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.197-207
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• 2012

This study investigated the role of plasmids and their relationship with the multiple antibiotic resistance of 30 Vibrios sp. isolated from molluscs and crustaceans sampled from the Kerala coastal waters of India. The biochemical identification and antibiotic resistance profiles were determined, followed by the plasmid profiles, conjugation and transformation efficiencies. The results showed a considerable difference in the level of bacterial resistance to various antibiotics; while all 30 strains were found to be MAR Vibrios sp. and their resistance patterns varied. All the strains were resistant to amoxycillin, ampicillin and carbeniciliin. 87% were resistant to rifampicin; 74% to cefuroxime; 67 to streptomycin; 53% to norfloxacin and ciprofloxacin and 47% to furazolidone and nalidixic acid. In addition to their antibiotic resistance, the plasmid DNA of the MAR Vibrios strains isolated from the molluscs and crustaceans was also studied. Nine strains isolated from crustaceans and molluscs were found to harbor 1-3 plasmids with sizes varying from 5. 98 kb to 19. 36 kb. The average transformation efficiency was about $5{\times}10^{-8}$ and the conjugation efficiency varied from $2.1{\times}10^{-3}$ to $10^{-9}$. A further study of antibiotic resistance patterns may be useful to test the extent of drug resistance in seafoods and help to devise a nationwide antibiotic policy.